xserver libX11 mesa git updaet 17 Mar 2011

1 files changed, 1488 insertions, 1488 deletions

diff --git a/mesalib/src/mesa/state_tracker/st_cb_drawpixels.c b/mesalib/src/mesa/state_tracker/st_cb_drawpixels.c
index 5c95eddd0..eccc20757 100644
--- a/mesalib/src/mesa/state_tracker/st_cb_drawpixels.c
+++ b/mesalib/src/mesa/state_tracker/st_cb_drawpixels.c
@@ -1,1488 +1,1488 @@
-/**************************************************************************

- * 

- * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.

- * All Rights Reserved.

- * 

- * Permission is hereby granted, free of charge, to any person obtaining a

- * copy of this software and associated documentation files (the

- * "Software"), to deal in the Software without restriction, including

- * without limitation the rights to use, copy, modify, merge, publish,

- * distribute, sub license, and/or sell copies of the Software, and to

- * permit persons to whom the Software is furnished to do so, subject to

- * the following conditions:

- * 

- * The above copyright notice and this permission notice (including the

- * next paragraph) shall be included in all copies or substantial portions

- * of the Software.

- * 

- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

- * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.

- * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR

- * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,

- * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE

- * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

- * 

- **************************************************************************/

-

- /*

-  * Authors:

-  *   Brian Paul

-  */

-

-#include "main/imports.h"

-#include "main/image.h"

-#include "main/bufferobj.h"

-#include "main/macros.h"

-#include "main/mfeatures.h"

-#include "main/mtypes.h"

-#include "main/pack.h"

-#include "main/pbo.h"

-#include "main/texformat.h"

-#include "main/texstore.h"

-#include "program/program.h"

-#include "program/prog_print.h"

-#include "program/prog_instruction.h"

-

-#include "st_atom.h"

-#include "st_atom_constbuf.h"

-#include "st_cb_drawpixels.h"

-#include "st_cb_readpixels.h"

-#include "st_cb_fbo.h"

-#include "st_context.h"

-#include "st_debug.h"

-#include "st_format.h"

-#include "st_program.h"

-#include "st_texture.h"

-

-#include "pipe/p_context.h"

-#include "pipe/p_defines.h"

-#include "tgsi/tgsi_ureg.h"

-#include "util/u_draw_quad.h"

-#include "util/u_format.h"

-#include "util/u_inlines.h"

-#include "util/u_math.h"

-#include "util/u_tile.h"

-#include "cso_cache/cso_context.h"

-

-

-#if FEATURE_drawpix

-

-/**

- * Check if the given program is:

- * 0: MOVE result.color, fragment.color;

- * 1: END;

- */

-static GLboolean

-is_passthrough_program(const struct gl_fragment_program *prog)

-{

-   if (prog->Base.NumInstructions == 2) {

-      const struct prog_instruction *inst = prog->Base.Instructions;

-      if (inst[0].Opcode == OPCODE_MOV &&

-          inst[1].Opcode == OPCODE_END &&

-          inst[0].DstReg.File == PROGRAM_OUTPUT &&

-          inst[0].DstReg.Index == FRAG_RESULT_COLOR &&

-          inst[0].DstReg.WriteMask == WRITEMASK_XYZW &&

-          inst[0].SrcReg[0].File == PROGRAM_INPUT &&

-          inst[0].SrcReg[0].Index == FRAG_ATTRIB_COL0 &&

-          inst[0].SrcReg[0].Swizzle == SWIZZLE_XYZW) {

-         return GL_TRUE;

-      }

-   }

-   return GL_FALSE;

-}

-

-

-

-/**

- * Make fragment shader for glDraw/CopyPixels.  This shader is made

- * by combining the pixel transfer shader with the user-defined shader.

- * \param fpIn  the current/incoming fragment program

- * \param fpOut  returns the combined fragment program

- */

-void

-st_make_drawpix_fragment_program(struct st_context *st,

-                                 struct gl_fragment_program *fpIn,

-                                 struct gl_fragment_program **fpOut)

-{

-   struct gl_program *newProg;

-

-   if (is_passthrough_program(fpIn)) {

-      newProg = (struct gl_program *) _mesa_clone_fragment_program(st->ctx,

-                                             &st->pixel_xfer.program->Base);

-   }

-   else {

-#if 0

-      /* debug */

-      printf("Base program:\n");

-      _mesa_print_program(&fpIn->Base);

-      printf("DrawPix program:\n");

-      _mesa_print_program(&st->pixel_xfer.program->Base.Base);

-#endif

-      newProg = _mesa_combine_programs(st->ctx,

-                                       &st->pixel_xfer.program->Base.Base,

-                                       &fpIn->Base);

-   }

-

-#if 0

-   /* debug */

-   printf("Combined DrawPixels program:\n");

-   _mesa_print_program(newProg);

-   printf("InputsRead: 0x%x\n", newProg->InputsRead);

-   printf("OutputsWritten: 0x%x\n", newProg->OutputsWritten);

-   _mesa_print_parameter_list(newProg->Parameters);

-#endif

-

-   *fpOut = (struct gl_fragment_program *) newProg;

-}

-

-

-/**

- * Create fragment program that does a TEX() instruction to get a Z and/or

- * stencil value value, then writes to FRAG_RESULT_DEPTH/FRAG_RESULT_STENCIL.

- * Used for glDrawPixels(GL_DEPTH_COMPONENT / GL_STENCIL_INDEX).

- * Pass fragment color through as-is.

- * \return pointer to the gl_fragment program

- */

-struct gl_fragment_program *

-st_make_drawpix_z_stencil_program(struct st_context *st,

-                                  GLboolean write_depth,

-                                  GLboolean write_stencil)

-{

-   struct gl_context *ctx = st->ctx;

-   struct gl_program *p;

-   struct gl_fragment_program *fp;

-   GLuint ic = 0;

-   const GLuint shaderIndex = write_depth * 2 + write_stencil;

-

-   assert(shaderIndex < Elements(st->drawpix.shaders));

-

-   if (st->drawpix.shaders[shaderIndex]) {

-      /* already have the proper shader */

-      return st->drawpix.shaders[shaderIndex];

-   }

-

-   /*

-    * Create shader now

-    */

-   p = ctx->Driver.NewProgram(ctx, GL_FRAGMENT_PROGRAM_ARB, 0);

-   if (!p)

-      return NULL;

-

-   p->NumInstructions = write_depth ? 2 : 1;

-   p->NumInstructions += write_stencil ? 1 : 0;

-

-   p->Instructions = _mesa_alloc_instructions(p->NumInstructions);

-   if (!p->Instructions) {

-      ctx->Driver.DeleteProgram(ctx, p);

-      return NULL;

-   }

-   _mesa_init_instructions(p->Instructions, p->NumInstructions);

-

-   if (write_depth) {

-      /* TEX result.depth, fragment.texcoord[0], texture[0], 2D; */

-      p->Instructions[ic].Opcode = OPCODE_TEX;

-      p->Instructions[ic].DstReg.File = PROGRAM_OUTPUT;

-      p->Instructions[ic].DstReg.Index = FRAG_RESULT_DEPTH;

-      p->Instructions[ic].DstReg.WriteMask = WRITEMASK_Z;

-      p->Instructions[ic].SrcReg[0].File = PROGRAM_INPUT;

-      p->Instructions[ic].SrcReg[0].Index = FRAG_ATTRIB_TEX0;

-      p->Instructions[ic].TexSrcUnit = 0;

-      p->Instructions[ic].TexSrcTarget = TEXTURE_2D_INDEX;

-      ic++;

-   }

-

-   if (write_stencil) {

-      /* TEX result.stencil, fragment.texcoord[0], texture[0], 2D; */

-      p->Instructions[ic].Opcode = OPCODE_TEX;

-      p->Instructions[ic].DstReg.File = PROGRAM_OUTPUT;

-      p->Instructions[ic].DstReg.Index = FRAG_RESULT_STENCIL;

-      p->Instructions[ic].DstReg.WriteMask = WRITEMASK_Y;

-      p->Instructions[ic].SrcReg[0].File = PROGRAM_INPUT;

-      p->Instructions[ic].SrcReg[0].Index = FRAG_ATTRIB_TEX0;

-      p->Instructions[ic].TexSrcUnit = 1;

-      p->Instructions[ic].TexSrcTarget = TEXTURE_2D_INDEX;

-      ic++;

-   }

-

-   /* END; */

-   p->Instructions[ic++].Opcode = OPCODE_END;

-

-   assert(ic == p->NumInstructions);

-

-   p->InputsRead = FRAG_BIT_TEX0 | FRAG_BIT_COL0;

-   p->OutputsWritten = 0;

-   if (write_depth)

-      p->OutputsWritten |= (1 << FRAG_RESULT_DEPTH);

-   if (write_stencil)

-      p->OutputsWritten |= (1 << FRAG_RESULT_STENCIL);

-

-   p->SamplersUsed =  0x1;  /* sampler 0 (bit 0) is used */

-   if (write_stencil)

-      p->SamplersUsed |= 1 << 1;

-

-   fp = (struct gl_fragment_program *) p;

-

-   /* save the new shader */

-   st->drawpix.shaders[shaderIndex] = fp;

-

-   return fp;

-}

-

-

-/**

- * Create a simple vertex shader that just passes through the

- * vertex position and texcoord (and optionally, color).

- */

-static void *

-make_passthrough_vertex_shader(struct st_context *st, 

-                               GLboolean passColor)

-{

-   if (!st->drawpix.vert_shaders[passColor]) {

-      struct ureg_program *ureg = ureg_create( TGSI_PROCESSOR_VERTEX );

-

-      if (ureg == NULL)

-         return NULL;

-

-      /* MOV result.pos, vertex.pos; */

-      ureg_MOV(ureg, 

-               ureg_DECL_output( ureg, TGSI_SEMANTIC_POSITION, 0 ),

-               ureg_DECL_vs_input( ureg, 0 ));

-      

-      /* MOV result.texcoord0, vertex.attr[1]; */

-      ureg_MOV(ureg, 

-               ureg_DECL_output( ureg, TGSI_SEMANTIC_GENERIC, 0 ),

-               ureg_DECL_vs_input( ureg, 1 ));

-      

-      if (passColor) {

-         /* MOV result.color0, vertex.attr[2]; */

-         ureg_MOV(ureg, 

-                  ureg_DECL_output( ureg, TGSI_SEMANTIC_COLOR, 0 ),

-                  ureg_DECL_vs_input( ureg, 2 ));

-      }

-

-      ureg_END( ureg );

-      

-      st->drawpix.vert_shaders[passColor] = 

-         ureg_create_shader_and_destroy( ureg, st->pipe );

-   }

-

-   return st->drawpix.vert_shaders[passColor];

-}

-

-

-/**

- * Return a texture base format for drawing/copying an image

- * of the given format.

- */

-static GLenum

-base_format(GLenum format)

-{

-   switch (format) {

-   case GL_DEPTH_COMPONENT:

-      return GL_DEPTH_COMPONENT;

-   case GL_DEPTH_STENCIL:

-      return GL_DEPTH_STENCIL;

-   case GL_STENCIL_INDEX:

-      return GL_STENCIL_INDEX;

-   default:

-      return GL_RGBA;

-   }

-}

-

-

-/**

- * Return a texture internalFormat for drawing/copying an image

- * of the given format and type.

- */

-static GLenum

-internal_format(GLenum format, GLenum type)

-{

-   switch (format) {

-   case GL_DEPTH_COMPONENT:

-      return GL_DEPTH_COMPONENT;

-   case GL_DEPTH_STENCIL:

-      return GL_DEPTH_STENCIL;

-   case GL_STENCIL_INDEX:

-      return GL_STENCIL_INDEX;

-   default:

-      if (_mesa_is_integer_format(format)) {

-         switch (type) {

-         case GL_BYTE:

-            return GL_RGBA8I;

-         case GL_UNSIGNED_BYTE:

-            return GL_RGBA8UI;

-         case GL_SHORT:

-            return GL_RGBA16I;

-         case GL_UNSIGNED_SHORT:

-            return GL_RGBA16UI;

-         case GL_INT:

-            return GL_RGBA32I;

-         case GL_UNSIGNED_INT:

-            return GL_RGBA32UI;

-         default:

-            assert(0 && "Unexpected type in internal_format()");

-            return GL_RGBA_INTEGER;

-         }

-      }

-      else {

-         return GL_RGBA;

-      }

-   }

-}

-

-

-/**

- * Create a temporary texture to hold an image of the given size.

- * If width, height are not POT and the driver only handles POT textures,

- * allocate the next larger size of texture that is POT.

- */

-static struct pipe_resource *

-alloc_texture(struct st_context *st, GLsizei width, GLsizei height,

-              enum pipe_format texFormat)

-{

-   struct pipe_resource *pt;

-

-   pt = st_texture_create(st, st->internal_target, texFormat, 0,

-                          width, height, 1, 1, PIPE_BIND_SAMPLER_VIEW);

-

-   return pt;

-}

-

-

-/**

- * Make texture containing an image for glDrawPixels image.

- * If 'pixels' is NULL, leave the texture image data undefined.

- */

-static struct pipe_resource *

-make_texture(struct st_context *st,

-	     GLsizei width, GLsizei height, GLenum format, GLenum type,

-	     const struct gl_pixelstore_attrib *unpack,

-	     const GLvoid *pixels)

-{

-   struct gl_context *ctx = st->ctx;

-   struct pipe_context *pipe = st->pipe;

-   gl_format mformat;

-   struct pipe_resource *pt;

-   enum pipe_format pipeFormat;

-   GLuint cpp;

-   GLenum baseFormat, intFormat;

-

-   baseFormat = base_format(format);

-   intFormat = internal_format(format, type);

-

-   mformat = st_ChooseTextureFormat_renderable(ctx, intFormat,

-                                               format, type, GL_FALSE);

-   assert(mformat);

-

-   pipeFormat = st_mesa_format_to_pipe_format(mformat);

-   assert(pipeFormat);

-   cpp = util_format_get_blocksize(pipeFormat);

-

-   pixels = _mesa_map_pbo_source(ctx, unpack, pixels);

-   if (!pixels)

-      return NULL;

-

-   /* alloc temporary texture */

-   pt = alloc_texture(st, width, height, pipeFormat);

-   if (!pt) {

-      _mesa_unmap_pbo_source(ctx, unpack);

-      return NULL;

-   }

-

-   {

-      struct pipe_transfer *transfer;

-      static const GLuint dstImageOffsets = 0;

-      GLboolean success;

-      GLubyte *dest;

-      const GLbitfield imageTransferStateSave = ctx->_ImageTransferState;

-

-      /* we'll do pixel transfer in a fragment shader */

-      ctx->_ImageTransferState = 0x0;

-

-      transfer = pipe_get_transfer(st->pipe, pt, 0, 0,

-                                   PIPE_TRANSFER_WRITE, 0, 0,

-                                   width, height);

-

-      /* map texture transfer */

-      dest = pipe_transfer_map(pipe, transfer);

-

-

-      /* Put image into texture transfer.

-       * Note that the image is actually going to be upside down in

-       * the texture.  We deal with that with texcoords.

-       */

-      success = _mesa_texstore(ctx, 2,           /* dims */

-                               baseFormat,       /* baseInternalFormat */

-                               mformat,          /* gl_format */

-                               dest,             /* dest */

-                               0, 0, 0,          /* dstX/Y/Zoffset */

-                               transfer->stride, /* dstRowStride, bytes */

-                               &dstImageOffsets, /* dstImageOffsets */

-                               width, height, 1, /* size */

-                               format, type,     /* src format/type */

-                               pixels,           /* data source */

-                               unpack);

-

-      /* unmap */

-      pipe_transfer_unmap(pipe, transfer);

-      pipe->transfer_destroy(pipe, transfer);

-

-      assert(success);

-

-      /* restore */

-      ctx->_ImageTransferState = imageTransferStateSave;

-   }

-

-   _mesa_unmap_pbo_source(ctx, unpack);

-

-   return pt;

-}

-

-

-/**

- * Draw quad with texcoords and optional color.

- * Coords are gallium window coords with y=0=top.

- * \param color  may be null

- * \param invertTex  if true, flip texcoords vertically

- */

-static void

-draw_quad(struct gl_context *ctx, GLfloat x0, GLfloat y0, GLfloat z,

-          GLfloat x1, GLfloat y1, const GLfloat *color,

-          GLboolean invertTex, GLfloat maxXcoord, GLfloat maxYcoord)

-{

-   struct st_context *st = st_context(ctx);

-   struct pipe_context *pipe = st->pipe;

-   GLfloat verts[4][3][4]; /* four verts, three attribs, XYZW */

-

-   /* setup vertex data */

-   {

-      const struct gl_framebuffer *fb = st->ctx->DrawBuffer;

-      const GLfloat fb_width = (GLfloat) fb->Width;

-      const GLfloat fb_height = (GLfloat) fb->Height;

-      const GLfloat clip_x0 = x0 / fb_width * 2.0f - 1.0f;

-      const GLfloat clip_y0 = y0 / fb_height * 2.0f - 1.0f;

-      const GLfloat clip_x1 = x1 / fb_width * 2.0f - 1.0f;

-      const GLfloat clip_y1 = y1 / fb_height * 2.0f - 1.0f;

-      const GLfloat sLeft = 0.0f, sRight = maxXcoord;

-      const GLfloat tTop = invertTex ? maxYcoord : 0.0f;

-      const GLfloat tBot = invertTex ? 0.0f : maxYcoord;

-      GLuint i;

-

-      /* upper-left */

-      verts[0][0][0] = clip_x0;    /* v[0].attr[0].x */

-      verts[0][0][1] = clip_y0;    /* v[0].attr[0].y */

-

-      /* upper-right */

-      verts[1][0][0] = clip_x1;

-      verts[1][0][1] = clip_y0;

-

-      /* lower-right */

-      verts[2][0][0] = clip_x1;

-      verts[2][0][1] = clip_y1;

-

-      /* lower-left */

-      verts[3][0][0] = clip_x0;

-      verts[3][0][1] = clip_y1;

-

-      verts[0][1][0] = sLeft; /* v[0].attr[1].S */

-      verts[0][1][1] = tTop;  /* v[0].attr[1].T */

-      verts[1][1][0] = sRight;

-      verts[1][1][1] = tTop;

-      verts[2][1][0] = sRight;

-      verts[2][1][1] = tBot;

-      verts[3][1][0] = sLeft;

-      verts[3][1][1] = tBot;

-

-      /* same for all verts: */

-      if (color) {

-         for (i = 0; i < 4; i++) {

-            verts[i][0][2] = z;         /* v[i].attr[0].z */

-            verts[i][0][3] = 1.0f;      /* v[i].attr[0].w */

-            verts[i][2][0] = color[0];  /* v[i].attr[2].r */

-            verts[i][2][1] = color[1];  /* v[i].attr[2].g */

-            verts[i][2][2] = color[2];  /* v[i].attr[2].b */

-            verts[i][2][3] = color[3];  /* v[i].attr[2].a */

-            verts[i][1][2] = 0.0f;      /* v[i].attr[1].R */

-            verts[i][1][3] = 1.0f;      /* v[i].attr[1].Q */

-         }

-      }

-      else {

-         for (i = 0; i < 4; i++) {

-            verts[i][0][2] = z;    /*Z*/

-            verts[i][0][3] = 1.0f; /*W*/

-            verts[i][1][2] = 0.0f; /*R*/

-            verts[i][1][3] = 1.0f; /*Q*/

-         }

-      }

-   }

-

-   {

-      struct pipe_resource *buf;

-

-      /* allocate/load buffer object with vertex data */

-      buf = pipe_buffer_create(pipe->screen,

-			       PIPE_BIND_VERTEX_BUFFER,

-			       PIPE_USAGE_STATIC,

-                               sizeof(verts));

-      pipe_buffer_write(st->pipe, buf, 0, sizeof(verts), verts);

-

-      util_draw_vertex_buffer(pipe, st->cso_context, buf, 0,

-                              PIPE_PRIM_QUADS,

-                              4,  /* verts */

-                              3); /* attribs/vert */

-      pipe_resource_reference(&buf, NULL);

-   }

-}

-

-

-

-static void

-draw_textured_quad(struct gl_context *ctx, GLint x, GLint y, GLfloat z,

-                   GLsizei width, GLsizei height,

-                   GLfloat zoomX, GLfloat zoomY,

-                   struct pipe_sampler_view **sv,

-                   int num_sampler_view,

-                   void *driver_vp,

-                   void *driver_fp,

-                   const GLfloat *color,

-                   GLboolean invertTex,

-                   GLboolean write_depth, GLboolean write_stencil)

-{

-   struct st_context *st = st_context(ctx);

-   struct pipe_context *pipe = st->pipe;

-   struct cso_context *cso = st->cso_context;

-   GLfloat x0, y0, x1, y1;

-   GLsizei maxSize;

-   boolean normalized = sv[0]->texture->target != PIPE_TEXTURE_RECT;

-

-   /* limit checks */

-   /* XXX if DrawPixels image is larger than max texture size, break

-    * it up into chunks.

-    */

-   maxSize = 1 << (pipe->screen->get_param(pipe->screen,

-                                        PIPE_CAP_MAX_TEXTURE_2D_LEVELS) - 1);

-   assert(width <= maxSize);

-   assert(height <= maxSize);

-

-   cso_save_rasterizer(cso);

-   cso_save_viewport(cso);

-   cso_save_samplers(cso);

-   cso_save_fragment_sampler_views(cso);

-   cso_save_fragment_shader(cso);

-   cso_save_vertex_shader(cso);

-   cso_save_vertex_elements(cso);

-   cso_save_vertex_buffers(cso);

-   if (write_stencil) {

-      cso_save_depth_stencil_alpha(cso);

-      cso_save_blend(cso);

-   }

-

-   /* rasterizer state: just scissor */

-   {

-      struct pipe_rasterizer_state rasterizer;

-      memset(&rasterizer, 0, sizeof(rasterizer));

-      rasterizer.gl_rasterization_rules = 1;

-      rasterizer.scissor = ctx->Scissor.Enabled;

-      cso_set_rasterizer(cso, &rasterizer);

-   }

-

-   if (write_stencil) {

-      /* Stencil writing bypasses the normal fragment pipeline to

-       * disable color writing and set stencil test to always pass.

-       */

-      struct pipe_depth_stencil_alpha_state dsa;

-      struct pipe_blend_state blend;

-

-      /* depth/stencil */

-      memset(&dsa, 0, sizeof(dsa));

-      dsa.stencil[0].enabled = 1;

-      dsa.stencil[0].func = PIPE_FUNC_ALWAYS;

-      dsa.stencil[0].writemask = ctx->Stencil.WriteMask[0] & 0xff;

-      dsa.stencil[0].zpass_op = PIPE_STENCIL_OP_REPLACE;

-      if (write_depth) {

-         /* writing depth+stencil: depth test always passes */

-         dsa.depth.enabled = 1;

-         dsa.depth.writemask = ctx->Depth.Mask;

-         dsa.depth.func = PIPE_FUNC_ALWAYS;

-      }

-      cso_set_depth_stencil_alpha(cso, &dsa);

-

-      /* blend (colormask) */

-      memset(&blend, 0, sizeof(blend));

-      cso_set_blend(cso, &blend);

-   }

-

-   /* fragment shader state: TEX lookup program */

-   cso_set_fragment_shader_handle(cso, driver_fp);

-

-   /* vertex shader state: position + texcoord pass-through */

-   cso_set_vertex_shader_handle(cso, driver_vp);

-

-

-   /* texture sampling state: */

-   {

-      struct pipe_sampler_state sampler;

-      memset(&sampler, 0, sizeof(sampler));

-      sampler.wrap_s = PIPE_TEX_WRAP_CLAMP;

-      sampler.wrap_t = PIPE_TEX_WRAP_CLAMP;

-      sampler.wrap_r = PIPE_TEX_WRAP_CLAMP;

-      sampler.min_img_filter = PIPE_TEX_FILTER_NEAREST;

-      sampler.min_mip_filter = PIPE_TEX_MIPFILTER_NONE;

-      sampler.mag_img_filter = PIPE_TEX_FILTER_NEAREST;

-      sampler.normalized_coords = normalized;

-

-      cso_single_sampler(cso, 0, &sampler);

-      if (num_sampler_view > 1) {

-         cso_single_sampler(cso, 1, &sampler);

-      }

-      cso_single_sampler_done(cso);

-   }

-

-   /* viewport state: viewport matching window dims */

-   {

-      const float w = (float) ctx->DrawBuffer->Width;

-      const float h = (float) ctx->DrawBuffer->Height;

-      struct pipe_viewport_state vp;

-      vp.scale[0] =  0.5f * w;

-      vp.scale[1] = -0.5f * h;

-      vp.scale[2] = 0.5f;

-      vp.scale[3] = 1.0f;

-      vp.translate[0] = 0.5f * w;

-      vp.translate[1] = 0.5f * h;

-      vp.translate[2] = 0.5f;

-      vp.translate[3] = 0.0f;

-      cso_set_viewport(cso, &vp);

-   }

-

-   cso_set_vertex_elements(cso, 3, st->velems_util_draw);

-

-   /* texture state: */

-   cso_set_fragment_sampler_views(cso, num_sampler_view, sv);

-

-   /* Compute Gallium window coords (y=0=top) with pixel zoom.

-    * Recall that these coords are transformed by the current

-    * vertex shader and viewport transformation.

-    */

-   if (st_fb_orientation(ctx->DrawBuffer) == Y_0_BOTTOM) {

-      y = ctx->DrawBuffer->Height - (int) (y + height * ctx->Pixel.ZoomY);

-      invertTex = !invertTex;

-   }

-

-   x0 = (GLfloat) x;

-   x1 = x + width * ctx->Pixel.ZoomX;

-   y0 = (GLfloat) y;

-   y1 = y + height * ctx->Pixel.ZoomY;

-

-   /* convert Z from [0,1] to [-1,-1] to match viewport Z scale/bias */

-   z = z * 2.0 - 1.0;

-

-   draw_quad(ctx, x0, y0, z, x1, y1, color, invertTex,

-             normalized ? ((GLfloat) width / sv[0]->texture->width0) : (GLfloat)width,

-             normalized ? ((GLfloat) height / sv[0]->texture->height0) : (GLfloat)height);

-

-   /* restore state */

-   cso_restore_rasterizer(cso);

-   cso_restore_viewport(cso);

-   cso_restore_samplers(cso);

-   cso_restore_fragment_sampler_views(cso);

-   cso_restore_fragment_shader(cso);

-   cso_restore_vertex_shader(cso);

-   cso_restore_vertex_elements(cso);

-   cso_restore_vertex_buffers(cso);

-   if (write_stencil) {

-      cso_restore_depth_stencil_alpha(cso);

-      cso_restore_blend(cso);

-   }

-}

-

-

-/**

- * Software fallback to do glDrawPixels(GL_STENCIL_INDEX) when we

- * can't use a fragment shader to write stencil values.

- */

-static void

-draw_stencil_pixels(struct gl_context *ctx, GLint x, GLint y,

-                    GLsizei width, GLsizei height, GLenum format, GLenum type,

-                    const struct gl_pixelstore_attrib *unpack,

-                    const GLvoid *pixels)

-{

-   struct st_context *st = st_context(ctx);

-   struct pipe_context *pipe = st->pipe;

-   struct st_renderbuffer *strb;

-   enum pipe_transfer_usage usage;

-   struct pipe_transfer *pt;

-   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0 || ctx->Pixel.ZoomY != 1.0;

-   GLint skipPixels;

-   ubyte *stmap;

-   struct gl_pixelstore_attrib clippedUnpack = *unpack;

-

-   if (!zoom) {

-      if (!_mesa_clip_drawpixels(ctx, &x, &y, &width, &height,

-                                 &clippedUnpack)) {

-         /* totally clipped */

-         return;

-      }

-   }

-

-   strb = st_renderbuffer(ctx->DrawBuffer->

-                          Attachment[BUFFER_STENCIL].Renderbuffer);

-

-   if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {

-      y = ctx->DrawBuffer->Height - y - height;

-   }

-

-   if(format != GL_DEPTH_STENCIL && 

-      util_format_get_component_bits(strb->format,

-                                     UTIL_FORMAT_COLORSPACE_ZS, 0) != 0)

-      usage = PIPE_TRANSFER_READ_WRITE;

-   else

-      usage = PIPE_TRANSFER_WRITE;

-

-   pt = pipe_get_transfer(st_context(ctx)->pipe, strb->texture, 0, 0,

-                                     usage, x, y,

-                                     width, height);

-

-   stmap = pipe_transfer_map(pipe, pt);

-

-   pixels = _mesa_map_pbo_source(ctx, &clippedUnpack, pixels);

-   assert(pixels);

-

-   /* if width > MAX_WIDTH, have to process image in chunks */

-   skipPixels = 0;

-   while (skipPixels < width) {

-      const GLint spanX = skipPixels;

-      const GLint spanWidth = MIN2(width - skipPixels, MAX_WIDTH);

-      GLint row;

-      for (row = 0; row < height; row++) {

-         GLubyte sValues[MAX_WIDTH];

-         GLuint zValues[MAX_WIDTH];

-         GLenum destType = GL_UNSIGNED_BYTE;

-         const GLvoid *source = _mesa_image_address2d(&clippedUnpack, pixels,

-                                                      width, height,

-                                                      format, type,

-                                                      row, skipPixels);

-         _mesa_unpack_stencil_span(ctx, spanWidth, destType, sValues,

-                                   type, source, &clippedUnpack,

-                                   ctx->_ImageTransferState);

-

-         if (format == GL_DEPTH_STENCIL) {

-            _mesa_unpack_depth_span(ctx, spanWidth, GL_UNSIGNED_INT, zValues,

-                                    (1 << 24) - 1, type, source,

-                                    &clippedUnpack);

-         }

-

-         if (zoom) {

-            _mesa_problem(ctx, "Gallium glDrawPixels(GL_STENCIL) with "

-                          "zoom not complete");

-         }

-

-         {

-            GLint spanY;

-

-            if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {

-               spanY = height - row - 1;

-            }

-            else {

-               spanY = row;

-            }

-

-            /* now pack the stencil (and Z) values in the dest format */

-            switch (pt->resource->format) {

-            case PIPE_FORMAT_S8_USCALED:

-               {

-                  ubyte *dest = stmap + spanY * pt->stride + spanX;

-                  assert(usage == PIPE_TRANSFER_WRITE);

-                  memcpy(dest, sValues, spanWidth);

-               }

-               break;

-            case PIPE_FORMAT_Z24_UNORM_S8_USCALED:

-               if (format == GL_DEPTH_STENCIL) {

-                  uint *dest = (uint *) (stmap + spanY * pt->stride + spanX*4);

-                  GLint k;

-                  assert(usage == PIPE_TRANSFER_WRITE);

-                  for (k = 0; k < spanWidth; k++) {

-                     dest[k] = zValues[k] | (sValues[k] << 24);

-                  }

-               }

-               else {

-                  uint *dest = (uint *) (stmap + spanY * pt->stride + spanX*4);

-                  GLint k;

-                  assert(usage == PIPE_TRANSFER_READ_WRITE);

-                  for (k = 0; k < spanWidth; k++) {

-                     dest[k] = (dest[k] & 0xffffff) | (sValues[k] << 24);

-                  }

-               }

-               break;

-            case PIPE_FORMAT_S8_USCALED_Z24_UNORM:

-               if (format == GL_DEPTH_STENCIL) {

-                  uint *dest = (uint *) (stmap + spanY * pt->stride + spanX*4);

-                  GLint k;

-                  assert(usage == PIPE_TRANSFER_WRITE);

-                  for (k = 0; k < spanWidth; k++) {

-                     dest[k] = (zValues[k] << 8) | (sValues[k] & 0xff);

-                  }

-               }

-               else {

-                  uint *dest = (uint *) (stmap + spanY * pt->stride + spanX*4);

-                  GLint k;

-                  assert(usage == PIPE_TRANSFER_READ_WRITE);

-                  for (k = 0; k < spanWidth; k++) {

-                     dest[k] = (dest[k] & 0xffffff00) | (sValues[k] & 0xff);

-                  }

-               }

-               break;

-            default:

-               assert(0);

-            }

-         }

-      }

-      skipPixels += spanWidth;

-   }

-

-   _mesa_unmap_pbo_source(ctx, &clippedUnpack);

-

-   /* unmap the stencil buffer */

-   pipe_transfer_unmap(pipe, pt);

-   pipe->transfer_destroy(pipe, pt);

-}

-

-

-/**

- * Get fragment program variant for a glDrawPixels or glCopyPixels

- * command for RGBA data.

- */

-static struct st_fp_variant *

-get_color_fp_variant(struct st_context *st)

-{

-   struct gl_context *ctx = st->ctx;

-   struct st_fp_variant_key key;

-   struct st_fp_variant *fpv;

-

-   memset(&key, 0, sizeof(key));

-

-   key.st = st;

-   key.drawpixels = 1;

-   key.scaleAndBias = (ctx->Pixel.RedBias != 0.0 ||

-                       ctx->Pixel.RedScale != 1.0 ||

-                       ctx->Pixel.GreenBias != 0.0 ||

-                       ctx->Pixel.GreenScale != 1.0 ||

-                       ctx->Pixel.BlueBias != 0.0 ||

-                       ctx->Pixel.BlueScale != 1.0 ||

-                       ctx->Pixel.AlphaBias != 0.0 ||

-                       ctx->Pixel.AlphaScale != 1.0);

-   key.pixelMaps = ctx->Pixel.MapColorFlag;

-

-   fpv = st_get_fp_variant(st, st->fp, &key);

-

-   return fpv;

-}

-

-

-/**

- * Get fragment program variant for a glDrawPixels or glCopyPixels

- * command for depth/stencil data.

- */

-static struct st_fp_variant *

-get_depth_stencil_fp_variant(struct st_context *st, GLboolean write_depth,

-                             GLboolean write_stencil)

-{

-   struct st_fp_variant_key key;

-   struct st_fp_variant *fpv;

-

-   memset(&key, 0, sizeof(key));

-

-   key.st = st;

-   key.drawpixels = 1;

-   key.drawpixels_z = write_depth;

-   key.drawpixels_stencil = write_stencil;

-

-   fpv = st_get_fp_variant(st, st->fp, &key);

-

-   return fpv;

-}

-

-

-/**

- * Called via ctx->Driver.DrawPixels()

- */

-static void

-st_DrawPixels(struct gl_context *ctx, GLint x, GLint y,

-              GLsizei width, GLsizei height,

-              GLenum format, GLenum type,

-              const struct gl_pixelstore_attrib *unpack, const GLvoid *pixels)

-{

-   void *driver_vp, *driver_fp;

-   struct st_context *st = st_context(ctx);

-   const GLfloat *color;

-   struct pipe_context *pipe = st->pipe;

-   GLboolean write_stencil = GL_FALSE, write_depth = GL_FALSE;

-   struct pipe_sampler_view *sv[2];

-   int num_sampler_view = 1;

-   enum pipe_format stencil_format = PIPE_FORMAT_NONE;

-   struct st_fp_variant *fpv;

-

-   if (format == GL_DEPTH_STENCIL)

-      write_stencil = write_depth = GL_TRUE;

-   else if (format == GL_STENCIL_INDEX)

-      write_stencil = GL_TRUE;

-   else if (format == GL_DEPTH_COMPONENT)

-      write_depth = GL_TRUE;

-

-   if (write_stencil) {

-      enum pipe_format tex_format;

-      /* can we write to stencil if not fallback */

-      if (!pipe->screen->get_param(pipe->screen, PIPE_CAP_SHADER_STENCIL_EXPORT))

-	 goto stencil_fallback;

-      

-      tex_format = st_choose_format(st->pipe->screen, base_format(format),

-                                    PIPE_TEXTURE_2D,

-				    0, PIPE_BIND_SAMPLER_VIEW);

-      if (tex_format == PIPE_FORMAT_Z24_UNORM_S8_USCALED)

-	 stencil_format = PIPE_FORMAT_X24S8_USCALED;

-      else if (tex_format == PIPE_FORMAT_S8_USCALED_Z24_UNORM)

-	 stencil_format = PIPE_FORMAT_S8X24_USCALED;

-      else

-	 stencil_format = PIPE_FORMAT_S8_USCALED;

-      if (stencil_format == PIPE_FORMAT_NONE)

-	 goto stencil_fallback;

-   }

-

-   /* Mesa state should be up to date by now */

-   assert(ctx->NewState == 0x0);

-

-   st_validate_state(st);

-

-   /*

-    * Get vertex/fragment shaders

-    */

-   if (write_depth || write_stencil) {

-      fpv = get_depth_stencil_fp_variant(st, write_depth, write_stencil);

-

-      driver_fp = fpv->driver_shader;

-

-      driver_vp = make_passthrough_vertex_shader(st, GL_TRUE);

-

-      color = ctx->Current.RasterColor;

-   }

-   else {

-      fpv = get_color_fp_variant(st);

-

-      driver_fp = fpv->driver_shader;

-

-      driver_vp = make_passthrough_vertex_shader(st, GL_FALSE);

-

-      color = NULL;

-      if (st->pixel_xfer.pixelmap_enabled) {

-	  sv[1] = st->pixel_xfer.pixelmap_sampler_view;

-	  num_sampler_view++;

-      }

-   }

-

-   /* update fragment program constants */

-   st_upload_constants(st, fpv->parameters, PIPE_SHADER_FRAGMENT);

-

-   /* draw with textured quad */

-   {

-      struct pipe_resource *pt

-         = make_texture(st, width, height, format, type, unpack, pixels);

-      if (pt) {

-         sv[0] = st_create_texture_sampler_view(st->pipe, pt);

-

-         if (sv[0]) {

-	    if (write_stencil) {

-	       sv[1] = st_create_texture_sampler_view_format(st->pipe, pt,

-                                                             stencil_format);

-	       num_sampler_view++;

-	    }

-

-            draw_textured_quad(ctx, x, y, ctx->Current.RasterPos[2],

-                               width, height,

-                               ctx->Pixel.ZoomX, ctx->Pixel.ZoomY,

-                               sv,

-                               num_sampler_view,

-                               driver_vp,

-                               driver_fp,

-                               color, GL_FALSE, write_depth, write_stencil);

-            pipe_sampler_view_reference(&sv[0], NULL);

-            if (num_sampler_view > 1)

-               pipe_sampler_view_reference(&sv[1], NULL);

-         }

-         pipe_resource_reference(&pt, NULL);

-      }

-   }

-   return;

-

-stencil_fallback:

-   draw_stencil_pixels(ctx, x, y, width, height, format, type,

-		       unpack, pixels);

-}

-

-

-

-/**

- * Software fallback for glCopyPixels(GL_STENCIL).

- */

-static void

-copy_stencil_pixels(struct gl_context *ctx, GLint srcx, GLint srcy,

-                    GLsizei width, GLsizei height,

-                    GLint dstx, GLint dsty)

-{

-   struct st_renderbuffer *rbDraw;

-   struct pipe_context *pipe = st_context(ctx)->pipe;

-   enum pipe_transfer_usage usage;

-   struct pipe_transfer *ptDraw;

-   ubyte *drawMap;

-   ubyte *buffer;

-   int i;

-

-   buffer = malloc(width * height * sizeof(ubyte));

-   if (!buffer) {

-      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels(stencil)");

-      return;

-   }

-

-   /* Get the dest renderbuffer.  If there's a wrapper, use the

-    * underlying renderbuffer.

-    */

-   rbDraw = st_renderbuffer(ctx->DrawBuffer->_StencilBuffer);

-   if (rbDraw->Base.Wrapped)

-      rbDraw = st_renderbuffer(rbDraw->Base.Wrapped);

-

-   /* this will do stencil pixel transfer ops */

-   st_read_stencil_pixels(ctx, srcx, srcy, width, height,

-                          GL_STENCIL_INDEX, GL_UNSIGNED_BYTE,

-                          &ctx->DefaultPacking, buffer);

-

-   if (0) {

-      /* debug code: dump stencil values */

-      GLint row, col;

-      for (row = 0; row < height; row++) {

-         printf("%3d: ", row);

-         for (col = 0; col < width; col++) {

-            printf("%02x ", buffer[col + row * width]);

-         }

-         printf("\n");

-      }

-   }

-

-   if (util_format_get_component_bits(rbDraw->format,

-                                     UTIL_FORMAT_COLORSPACE_ZS, 0) != 0)

-      usage = PIPE_TRANSFER_READ_WRITE;

-   else

-      usage = PIPE_TRANSFER_WRITE;

-

-   if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {

-      dsty = rbDraw->Base.Height - dsty - height;

-   }

-

-   ptDraw = pipe_get_transfer(st_context(ctx)->pipe,

-                              rbDraw->texture, 0, 0,

-                              usage, dstx, dsty,

-                              width, height);

-

-   assert(util_format_get_blockwidth(ptDraw->resource->format) == 1);

-   assert(util_format_get_blockheight(ptDraw->resource->format) == 1);

-

-   /* map the stencil buffer */

-   drawMap = pipe_transfer_map(pipe, ptDraw);

-

-   /* draw */

-   /* XXX PixelZoom not handled yet */

-   for (i = 0; i < height; i++) {

-      ubyte *dst;

-      const ubyte *src;

-      int y;

-

-      y = i;

-

-      if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {

-         y = height - y - 1;

-      }

-

-      dst = drawMap + y * ptDraw->stride;

-      src = buffer + i * width;

-

-      switch (ptDraw->resource->format) {

-      case PIPE_FORMAT_Z24_UNORM_S8_USCALED:

-         {

-            uint *dst4 = (uint *) dst;

-            int j;

-            assert(usage == PIPE_TRANSFER_READ_WRITE);

-            for (j = 0; j < width; j++) {

-               *dst4 = (*dst4 & 0xffffff) | (src[j] << 24);

-               dst4++;

-            }

-         }

-         break;

-      case PIPE_FORMAT_S8_USCALED_Z24_UNORM:

-         {

-            uint *dst4 = (uint *) dst;

-            int j;

-            assert(usage == PIPE_TRANSFER_READ_WRITE);

-            for (j = 0; j < width; j++) {

-               *dst4 = (*dst4 & 0xffffff00) | (src[j] & 0xff);

-               dst4++;

-            }

-         }

-         break;

-      case PIPE_FORMAT_S8_USCALED:

-         assert(usage == PIPE_TRANSFER_WRITE);

-         memcpy(dst, src, width);

-         break;

-      default:

-         assert(0);

-      }

-   }

-

-   free(buffer);

-

-   /* unmap the stencil buffer */

-   pipe_transfer_unmap(pipe, ptDraw);

-   pipe->transfer_destroy(pipe, ptDraw);

-}

-

-

-/** Do the src/dest regions overlap? */

-static GLboolean

-regions_overlap(GLint srcX, GLint srcY, GLint dstX, GLint dstY,

-                GLsizei width, GLsizei height)

-{

-   if (srcX + width <= dstX ||

-       dstX + width <= srcX ||

-       srcY + height <= dstY ||

-       dstY + height <= srcY)

-      return GL_FALSE;

-   else

-      return GL_TRUE;

-}

-

-

-/**

- * Try to do a glCopyPixels for simple cases with a blit by calling

- * pipe->resource_copy_region().

- *

- * We can do this when we're copying color pixels (depth/stencil

- * eventually) with no pixel zoom, no pixel transfer ops, no

- * per-fragment ops, the src/dest regions don't overlap and the

- * src/dest pixel formats are the same.

- */

-static GLboolean

-blit_copy_pixels(struct gl_context *ctx, GLint srcx, GLint srcy,

-                 GLsizei width, GLsizei height,

-                 GLint dstx, GLint dsty, GLenum type)

-{

-   struct st_context *st = st_context(ctx);

-   struct pipe_context *pipe = st->pipe;

-   struct gl_pixelstore_attrib pack, unpack;

-   GLint readX, readY, readW, readH;

-

-   if (type == GL_COLOR &&

-       ctx->Pixel.ZoomX == 1.0 &&

-       ctx->Pixel.ZoomY == 1.0 &&

-       ctx->_ImageTransferState == 0x0 &&

-       !ctx->Color.BlendEnabled &&

-       !ctx->Color.AlphaEnabled &&

-       !ctx->Depth.Test &&

-       !ctx->Fog.Enabled &&

-       !ctx->Stencil.Enabled &&

-       !ctx->FragmentProgram.Enabled &&

-       !ctx->VertexProgram.Enabled &&

-       !ctx->Shader.CurrentFragmentProgram &&

-       st_fb_orientation(ctx->ReadBuffer) == st_fb_orientation(ctx->DrawBuffer) &&

-       ctx->DrawBuffer->_NumColorDrawBuffers == 1) {

-      struct st_renderbuffer *rbRead, *rbDraw;

-      GLint drawX, drawY;

-

-      /*

-       * Clip the read region against the src buffer bounds.

-       * We'll still allocate a temporary buffer/texture for the original

-       * src region size but we'll only read the region which is on-screen.

-       * This may mean that we draw garbage pixels into the dest region, but

-       * that's expected.

-       */

-      readX = srcx;

-      readY = srcy;

-      readW = width;

-      readH = height;

-      pack = ctx->DefaultPacking;

-      if (!_mesa_clip_readpixels(ctx, &readX, &readY, &readW, &readH, &pack))

-         return GL_TRUE; /* all done */

-

-      /* clip against dest buffer bounds and scissor box */

-      drawX = dstx + pack.SkipPixels;

-      drawY = dsty + pack.SkipRows;

-      unpack = pack;

-      if (!_mesa_clip_drawpixels(ctx, &drawX, &drawY, &readW, &readH, &unpack))

-         return GL_TRUE; /* all done */

-

-      readX = readX - pack.SkipPixels + unpack.SkipPixels;

-      readY = readY - pack.SkipRows + unpack.SkipRows;

-

-      rbRead = st_get_color_read_renderbuffer(ctx);

-      rbDraw = st_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[0]);

-

-      if ((rbRead != rbDraw ||

-           !regions_overlap(readX, readY, drawX, drawY, readW, readH)) &&

-          rbRead->Base.Format == rbDraw->Base.Format) {

-         struct pipe_box srcBox;

-

-         /* flip src/dst position if needed */

-         if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {

-            /* both buffers will have the same orientation */

-            readY = ctx->ReadBuffer->Height - readY - readH;

-            drawY = ctx->DrawBuffer->Height - drawY - readH;

-         }

-

-         u_box_2d(readX, readY, readW, readH, &srcBox);

-

-         pipe->resource_copy_region(pipe,

-                                    rbDraw->texture, 0, drawX, drawY, 0,

-                                    rbRead->texture, 0, &srcBox);

-         return GL_TRUE;

-      }

-   }

-

-   return GL_FALSE;

-}

-

-

-static void

-st_CopyPixels(struct gl_context *ctx, GLint srcx, GLint srcy,

-              GLsizei width, GLsizei height,

-              GLint dstx, GLint dsty, GLenum type)

-{

-   struct st_context *st = st_context(ctx);

-   struct pipe_context *pipe = st->pipe;

-   struct pipe_screen *screen = pipe->screen;

-   struct st_renderbuffer *rbRead;

-   void *driver_vp, *driver_fp;

-   struct pipe_resource *pt;

-   struct pipe_sampler_view *sv[2];

-   int num_sampler_view = 1;

-   GLfloat *color;

-   enum pipe_format srcFormat, texFormat;

-   GLboolean invertTex = GL_FALSE;

-   GLint readX, readY, readW, readH;

-   GLuint sample_count;

-   struct gl_pixelstore_attrib pack = ctx->DefaultPacking;

-   struct st_fp_variant *fpv;

-

-   st_validate_state(st);

-

-   if (type == GL_STENCIL) {

-      /* can't use texturing to do stencil */

-      copy_stencil_pixels(ctx, srcx, srcy, width, height, dstx, dsty);

-      return;

-   }

-

-   if (blit_copy_pixels(ctx, srcx, srcy, width, height, dstx, dsty, type))

-      return;

-

-   /*

-    * The subsequent code implements glCopyPixels by copying the source

-    * pixels into a temporary texture that's then applied to a textured quad.

-    * When we draw the textured quad, all the usual per-fragment operations

-    * are handled.

-    */

-

-

-   /*

-    * Get vertex/fragment shaders

-    */

-   if (type == GL_COLOR) {

-      rbRead = st_get_color_read_renderbuffer(ctx);

-      color = NULL;

-

-      fpv = get_color_fp_variant(st);

-      driver_fp = fpv->driver_shader;

-

-      driver_vp = make_passthrough_vertex_shader(st, GL_FALSE);

-

-      if (st->pixel_xfer.pixelmap_enabled) {

-	  sv[1] = st->pixel_xfer.pixelmap_sampler_view;

-	  num_sampler_view++;

-      }

-   }

-   else {

-      assert(type == GL_DEPTH);

-      rbRead = st_renderbuffer(ctx->ReadBuffer->_DepthBuffer);

-      color = ctx->Current.Attrib[VERT_ATTRIB_COLOR0];

-

-      fpv = get_depth_stencil_fp_variant(st, GL_TRUE, GL_FALSE);

-      driver_fp = fpv->driver_shader;

-

-      driver_vp = make_passthrough_vertex_shader(st, GL_TRUE);

-   }

-

-   /* update fragment program constants */

-   st_upload_constants(st, fpv->parameters, PIPE_SHADER_FRAGMENT);

-

-

-   if (rbRead->Base.Wrapped)

-      rbRead = st_renderbuffer(rbRead->Base.Wrapped);

-

-   sample_count = rbRead->texture->nr_samples;

-   /* I believe this would be legal, presumably would need to do a resolve

-      for color, and for depth/stencil spec says to just use one of the

-      depth/stencil samples per pixel? Need some transfer clarifications. */

-   assert(sample_count < 2);

-

-   srcFormat = rbRead->texture->format;

-

-   if (screen->is_format_supported(screen, srcFormat, st->internal_target,

-                                   sample_count,

-                                   PIPE_BIND_SAMPLER_VIEW)) {

-      texFormat = srcFormat;

-   }

-   else {

-      /* srcFormat can't be used as a texture format */

-      if (type == GL_DEPTH) {

-         texFormat = st_choose_format(screen, GL_DEPTH_COMPONENT,

-                                      st->internal_target, sample_count,

-                                      PIPE_BIND_DEPTH_STENCIL);

-         assert(texFormat != PIPE_FORMAT_NONE);

-      }

-      else {

-         /* default color format */

-         texFormat = st_choose_format(screen, GL_RGBA, st->internal_target,

-                                      sample_count, PIPE_BIND_SAMPLER_VIEW);

-         assert(texFormat != PIPE_FORMAT_NONE);

-      }

-   }

-

-   /* Invert src region if needed */

-   if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {

-      srcy = ctx->ReadBuffer->Height - srcy - height;

-      invertTex = !invertTex;

-   }

-

-   /* Clip the read region against the src buffer bounds.

-    * We'll still allocate a temporary buffer/texture for the original

-    * src region size but we'll only read the region which is on-screen.

-    * This may mean that we draw garbage pixels into the dest region, but

-    * that's expected.

-    */

-   readX = srcx;

-   readY = srcy;

-   readW = width;

-   readH = height;

-   _mesa_clip_readpixels(ctx, &readX, &readY, &readW, &readH, &pack);

-   readW = MAX2(0, readW);

-   readH = MAX2(0, readH);

-

-   /* alloc temporary texture */

-   pt = alloc_texture(st, width, height, texFormat);

-   if (!pt)

-      return;

-

-   sv[0] = st_create_texture_sampler_view(st->pipe, pt);

-   if (!sv[0]) {

-      pipe_resource_reference(&pt, NULL);

-      return;

-   }

-

-   /* Make temporary texture which is a copy of the src region.

-    */

-   if (srcFormat == texFormat) {

-      struct pipe_box src_box;

-      u_box_2d(readX, readY, readW, readH, &src_box);

-      /* copy source framebuffer surface into mipmap/texture */

-      pipe->resource_copy_region(pipe,

-                                 pt,                                /* dest tex */

-                                 0,

-                                 pack.SkipPixels, pack.SkipRows, 0, /* dest pos */

-                                 rbRead->texture,                   /* src tex */

-                                 0,

-                                 &src_box);

-

-   }

-   else {

-      /* CPU-based fallback/conversion */

-      struct pipe_transfer *ptRead =

-         pipe_get_transfer(st->pipe, rbRead->texture,

-                           0, 0, /* level, layer */

-                           PIPE_TRANSFER_READ,

-                           readX, readY, readW, readH);

-      struct pipe_transfer *ptTex;

-      enum pipe_transfer_usage transfer_usage;

-

-      if (ST_DEBUG & DEBUG_FALLBACK)

-         debug_printf("%s: fallback processing\n", __FUNCTION__);

-

-      if (type == GL_DEPTH && util_format_is_depth_and_stencil(pt->format))

-         transfer_usage = PIPE_TRANSFER_READ_WRITE;

-      else

-         transfer_usage = PIPE_TRANSFER_WRITE;

-

-      ptTex = pipe_get_transfer(st->pipe, pt, 0, 0, transfer_usage,

-                                0, 0, width, height);

-

-      /* copy image from ptRead surface to ptTex surface */

-      if (type == GL_COLOR) {

-         /* alternate path using get/put_tile() */

-         GLfloat *buf = (GLfloat *) malloc(width * height * 4 * sizeof(GLfloat));

-         enum pipe_format readFormat, drawFormat;

-         readFormat = util_format_linear(rbRead->texture->format);

-         drawFormat = util_format_linear(pt->format);

-         pipe_get_tile_rgba_format(pipe, ptRead, 0, 0, readW, readH,

-                                   readFormat, buf);

-         pipe_put_tile_rgba_format(pipe, ptTex, pack.SkipPixels, pack.SkipRows,

-                                   readW, readH, drawFormat, buf);

-         free(buf);

-      }

-      else {

-         /* GL_DEPTH */

-         GLuint *buf = (GLuint *) malloc(width * height * sizeof(GLuint));

-         pipe_get_tile_z(pipe, ptRead, 0, 0, readW, readH, buf);

-         pipe_put_tile_z(pipe, ptTex, pack.SkipPixels, pack.SkipRows,

-                         readW, readH, buf);

-         free(buf);

-      }

-

-      pipe->transfer_destroy(pipe, ptRead);

-      pipe->transfer_destroy(pipe, ptTex);

-   }

-

-   /* OK, the texture 'pt' contains the src image/pixels.  Now draw a

-    * textured quad with that texture.

-    */

-   draw_textured_quad(ctx, dstx, dsty, ctx->Current.RasterPos[2],

-                      width, height, ctx->Pixel.ZoomX, ctx->Pixel.ZoomY,

-                      sv,

-                      num_sampler_view,

-                      driver_vp, 

-                      driver_fp,

-                      color, invertTex, GL_FALSE, GL_FALSE);

-

-   pipe_resource_reference(&pt, NULL);

-   pipe_sampler_view_reference(&sv[0], NULL);

-}

-

-

-

-void st_init_drawpixels_functions(struct dd_function_table *functions)

-{

-   functions->DrawPixels = st_DrawPixels;

-   functions->CopyPixels = st_CopyPixels;

-}

-

-

-void

-st_destroy_drawpix(struct st_context *st)

-{

-   GLuint i;

-

-   for (i = 0; i < Elements(st->drawpix.shaders); i++) {

-      if (st->drawpix.shaders[i])

-         _mesa_reference_fragprog(st->ctx, &st->drawpix.shaders[i], NULL);

-   }

-

-   st_reference_fragprog(st, &st->pixel_xfer.combined_prog, NULL);

-   if (st->drawpix.vert_shaders[0])

-      ureg_free_tokens(st->drawpix.vert_shaders[0]);

-   if (st->drawpix.vert_shaders[1])

-      ureg_free_tokens(st->drawpix.vert_shaders[1]);

-}

-

-#endif /* FEATURE_drawpix */

+/**************************************************************************
+ * 
+ * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ * 
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ * 
+ **************************************************************************/
+
+ /*
+  * Authors:
+  *   Brian Paul
+  */
+
+#include "main/imports.h"
+#include "main/image.h"
+#include "main/bufferobj.h"
+#include "main/macros.h"
+#include "main/mfeatures.h"
+#include "main/mtypes.h"
+#include "main/pack.h"
+#include "main/pbo.h"
+#include "main/texformat.h"
+#include "main/texstore.h"
+#include "program/program.h"
+#include "program/prog_print.h"
+#include "program/prog_instruction.h"
+
+#include "st_atom.h"
+#include "st_atom_constbuf.h"
+#include "st_cb_drawpixels.h"
+#include "st_cb_readpixels.h"
+#include "st_cb_fbo.h"
+#include "st_context.h"
+#include "st_debug.h"
+#include "st_format.h"
+#include "st_program.h"
+#include "st_texture.h"
+
+#include "pipe/p_context.h"
+#include "pipe/p_defines.h"
+#include "tgsi/tgsi_ureg.h"
+#include "util/u_draw_quad.h"
+#include "util/u_format.h"
+#include "util/u_inlines.h"
+#include "util/u_math.h"
+#include "util/u_tile.h"
+#include "cso_cache/cso_context.h"
+
+
+#if FEATURE_drawpix
+
+/**
+ * Check if the given program is:
+ * 0: MOVE result.color, fragment.color;
+ * 1: END;
+ */
+static GLboolean
+is_passthrough_program(const struct gl_fragment_program *prog)
+{
+   if (prog->Base.NumInstructions == 2) {
+      const struct prog_instruction *inst = prog->Base.Instructions;
+      if (inst[0].Opcode == OPCODE_MOV &&
+          inst[1].Opcode == OPCODE_END &&
+          inst[0].DstReg.File == PROGRAM_OUTPUT &&
+          inst[0].DstReg.Index == FRAG_RESULT_COLOR &&
+          inst[0].DstReg.WriteMask == WRITEMASK_XYZW &&
+          inst[0].SrcReg[0].File == PROGRAM_INPUT &&
+          inst[0].SrcReg[0].Index == FRAG_ATTRIB_COL0 &&
+          inst[0].SrcReg[0].Swizzle == SWIZZLE_XYZW) {
+         return GL_TRUE;
+      }
+   }
+   return GL_FALSE;
+}
+
+
+
+/**
+ * Make fragment shader for glDraw/CopyPixels.  This shader is made
+ * by combining the pixel transfer shader with the user-defined shader.
+ * \param fpIn  the current/incoming fragment program
+ * \param fpOut  returns the combined fragment program
+ */
+void
+st_make_drawpix_fragment_program(struct st_context *st,
+                                 struct gl_fragment_program *fpIn,
+                                 struct gl_fragment_program **fpOut)
+{
+   struct gl_program *newProg;
+
+   if (is_passthrough_program(fpIn)) {
+      newProg = (struct gl_program *) _mesa_clone_fragment_program(st->ctx,
+                                             &st->pixel_xfer.program->Base);
+   }
+   else {
+#if 0
+      /* debug */
+      printf("Base program:\n");
+      _mesa_print_program(&fpIn->Base);
+      printf("DrawPix program:\n");
+      _mesa_print_program(&st->pixel_xfer.program->Base.Base);
+#endif
+      newProg = _mesa_combine_programs(st->ctx,
+                                       &st->pixel_xfer.program->Base.Base,
+                                       &fpIn->Base);
+   }
+
+#if 0
+   /* debug */
+   printf("Combined DrawPixels program:\n");
+   _mesa_print_program(newProg);
+   printf("InputsRead: 0x%x\n", newProg->InputsRead);
+   printf("OutputsWritten: 0x%x\n", newProg->OutputsWritten);
+   _mesa_print_parameter_list(newProg->Parameters);
+#endif
+
+   *fpOut = (struct gl_fragment_program *) newProg;
+}
+
+
+/**
+ * Create fragment program that does a TEX() instruction to get a Z and/or
+ * stencil value value, then writes to FRAG_RESULT_DEPTH/FRAG_RESULT_STENCIL.
+ * Used for glDrawPixels(GL_DEPTH_COMPONENT / GL_STENCIL_INDEX).
+ * Pass fragment color through as-is.
+ * \return pointer to the gl_fragment program
+ */
+struct gl_fragment_program *
+st_make_drawpix_z_stencil_program(struct st_context *st,
+                                  GLboolean write_depth,
+                                  GLboolean write_stencil)
+{
+   struct gl_context *ctx = st->ctx;
+   struct gl_program *p;
+   struct gl_fragment_program *fp;
+   GLuint ic = 0;
+   const GLuint shaderIndex = write_depth * 2 + write_stencil;
+
+   assert(shaderIndex < Elements(st->drawpix.shaders));
+
+   if (st->drawpix.shaders[shaderIndex]) {
+      /* already have the proper shader */
+      return st->drawpix.shaders[shaderIndex];
+   }
+
+   /*
+    * Create shader now
+    */
+   p = ctx->Driver.NewProgram(ctx, GL_FRAGMENT_PROGRAM_ARB, 0);
+   if (!p)
+      return NULL;
+
+   p->NumInstructions = write_depth ? 2 : 1;
+   p->NumInstructions += write_stencil ? 1 : 0;
+
+   p->Instructions = _mesa_alloc_instructions(p->NumInstructions);
+   if (!p->Instructions) {
+      ctx->Driver.DeleteProgram(ctx, p);
+      return NULL;
+   }
+   _mesa_init_instructions(p->Instructions, p->NumInstructions);
+
+   if (write_depth) {
+      /* TEX result.depth, fragment.texcoord[0], texture[0], 2D; */
+      p->Instructions[ic].Opcode = OPCODE_TEX;
+      p->Instructions[ic].DstReg.File = PROGRAM_OUTPUT;
+      p->Instructions[ic].DstReg.Index = FRAG_RESULT_DEPTH;
+      p->Instructions[ic].DstReg.WriteMask = WRITEMASK_Z;
+      p->Instructions[ic].SrcReg[0].File = PROGRAM_INPUT;
+      p->Instructions[ic].SrcReg[0].Index = FRAG_ATTRIB_TEX0;
+      p->Instructions[ic].TexSrcUnit = 0;
+      p->Instructions[ic].TexSrcTarget = TEXTURE_2D_INDEX;
+      ic++;
+   }
+
+   if (write_stencil) {
+      /* TEX result.stencil, fragment.texcoord[0], texture[0], 2D; */
+      p->Instructions[ic].Opcode = OPCODE_TEX;
+      p->Instructions[ic].DstReg.File = PROGRAM_OUTPUT;
+      p->Instructions[ic].DstReg.Index = FRAG_RESULT_STENCIL;
+      p->Instructions[ic].DstReg.WriteMask = WRITEMASK_Y;
+      p->Instructions[ic].SrcReg[0].File = PROGRAM_INPUT;
+      p->Instructions[ic].SrcReg[0].Index = FRAG_ATTRIB_TEX0;
+      p->Instructions[ic].TexSrcUnit = 1;
+      p->Instructions[ic].TexSrcTarget = TEXTURE_2D_INDEX;
+      ic++;
+   }
+
+   /* END; */
+   p->Instructions[ic++].Opcode = OPCODE_END;
+
+   assert(ic == p->NumInstructions);
+
+   p->InputsRead = FRAG_BIT_TEX0 | FRAG_BIT_COL0;
+   p->OutputsWritten = 0;
+   if (write_depth)
+      p->OutputsWritten |= BITFIELD64_BIT(FRAG_RESULT_DEPTH);
+   if (write_stencil)
+      p->OutputsWritten |= BITFIELD64_BIT(FRAG_RESULT_STENCIL);
+
+   p->SamplersUsed =  0x1;  /* sampler 0 (bit 0) is used */
+   if (write_stencil)
+      p->SamplersUsed |= 1 << 1;
+
+   fp = (struct gl_fragment_program *) p;
+
+   /* save the new shader */
+   st->drawpix.shaders[shaderIndex] = fp;
+
+   return fp;
+}
+
+
+/**
+ * Create a simple vertex shader that just passes through the
+ * vertex position and texcoord (and optionally, color).
+ */
+static void *
+make_passthrough_vertex_shader(struct st_context *st, 
+                               GLboolean passColor)
+{
+   if (!st->drawpix.vert_shaders[passColor]) {
+      struct ureg_program *ureg = ureg_create( TGSI_PROCESSOR_VERTEX );
+
+      if (ureg == NULL)
+         return NULL;
+
+      /* MOV result.pos, vertex.pos; */
+      ureg_MOV(ureg, 
+               ureg_DECL_output( ureg, TGSI_SEMANTIC_POSITION, 0 ),
+               ureg_DECL_vs_input( ureg, 0 ));
+      
+      /* MOV result.texcoord0, vertex.attr[1]; */
+      ureg_MOV(ureg, 
+               ureg_DECL_output( ureg, TGSI_SEMANTIC_GENERIC, 0 ),
+               ureg_DECL_vs_input( ureg, 1 ));
+      
+      if (passColor) {
+         /* MOV result.color0, vertex.attr[2]; */
+         ureg_MOV(ureg, 
+                  ureg_DECL_output( ureg, TGSI_SEMANTIC_COLOR, 0 ),
+                  ureg_DECL_vs_input( ureg, 2 ));
+      }
+
+      ureg_END( ureg );
+      
+      st->drawpix.vert_shaders[passColor] = 
+         ureg_create_shader_and_destroy( ureg, st->pipe );
+   }
+
+   return st->drawpix.vert_shaders[passColor];
+}
+
+
+/**
+ * Return a texture base format for drawing/copying an image
+ * of the given format.
+ */
+static GLenum
+base_format(GLenum format)
+{
+   switch (format) {
+   case GL_DEPTH_COMPONENT:
+      return GL_DEPTH_COMPONENT;
+   case GL_DEPTH_STENCIL:
+      return GL_DEPTH_STENCIL;
+   case GL_STENCIL_INDEX:
+      return GL_STENCIL_INDEX;
+   default:
+      return GL_RGBA;
+   }
+}
+
+
+/**
+ * Return a texture internalFormat for drawing/copying an image
+ * of the given format and type.
+ */
+static GLenum
+internal_format(GLenum format, GLenum type)
+{
+   switch (format) {
+   case GL_DEPTH_COMPONENT:
+      return GL_DEPTH_COMPONENT;
+   case GL_DEPTH_STENCIL:
+      return GL_DEPTH_STENCIL;
+   case GL_STENCIL_INDEX:
+      return GL_STENCIL_INDEX;
+   default:
+      if (_mesa_is_integer_format(format)) {
+         switch (type) {
+         case GL_BYTE:
+            return GL_RGBA8I;
+         case GL_UNSIGNED_BYTE:
+            return GL_RGBA8UI;
+         case GL_SHORT:
+            return GL_RGBA16I;
+         case GL_UNSIGNED_SHORT:
+            return GL_RGBA16UI;
+         case GL_INT:
+            return GL_RGBA32I;
+         case GL_UNSIGNED_INT:
+            return GL_RGBA32UI;
+         default:
+            assert(0 && "Unexpected type in internal_format()");
+            return GL_RGBA_INTEGER;
+         }
+      }
+      else {
+         return GL_RGBA;
+      }
+   }
+}
+
+
+/**
+ * Create a temporary texture to hold an image of the given size.
+ * If width, height are not POT and the driver only handles POT textures,
+ * allocate the next larger size of texture that is POT.
+ */
+static struct pipe_resource *
+alloc_texture(struct st_context *st, GLsizei width, GLsizei height,
+              enum pipe_format texFormat)
+{
+   struct pipe_resource *pt;
+
+   pt = st_texture_create(st, st->internal_target, texFormat, 0,
+                          width, height, 1, 1, PIPE_BIND_SAMPLER_VIEW);
+
+   return pt;
+}
+
+
+/**
+ * Make texture containing an image for glDrawPixels image.
+ * If 'pixels' is NULL, leave the texture image data undefined.
+ */
+static struct pipe_resource *
+make_texture(struct st_context *st,
+	     GLsizei width, GLsizei height, GLenum format, GLenum type,
+	     const struct gl_pixelstore_attrib *unpack,
+	     const GLvoid *pixels)
+{
+   struct gl_context *ctx = st->ctx;
+   struct pipe_context *pipe = st->pipe;
+   gl_format mformat;
+   struct pipe_resource *pt;
+   enum pipe_format pipeFormat;
+   GLuint cpp;
+   GLenum baseFormat, intFormat;
+
+   baseFormat = base_format(format);
+   intFormat = internal_format(format, type);
+
+   mformat = st_ChooseTextureFormat_renderable(ctx, intFormat,
+                                               format, type, GL_FALSE);
+   assert(mformat);
+
+   pipeFormat = st_mesa_format_to_pipe_format(mformat);
+   assert(pipeFormat);
+   cpp = util_format_get_blocksize(pipeFormat);
+
+   pixels = _mesa_map_pbo_source(ctx, unpack, pixels);
+   if (!pixels)
+      return NULL;
+
+   /* alloc temporary texture */
+   pt = alloc_texture(st, width, height, pipeFormat);
+   if (!pt) {
+      _mesa_unmap_pbo_source(ctx, unpack);
+      return NULL;
+   }
+
+   {
+      struct pipe_transfer *transfer;
+      static const GLuint dstImageOffsets = 0;
+      GLboolean success;
+      GLubyte *dest;
+      const GLbitfield imageTransferStateSave = ctx->_ImageTransferState;
+
+      /* we'll do pixel transfer in a fragment shader */
+      ctx->_ImageTransferState = 0x0;
+
+      transfer = pipe_get_transfer(st->pipe, pt, 0, 0,
+                                   PIPE_TRANSFER_WRITE, 0, 0,
+                                   width, height);
+
+      /* map texture transfer */
+      dest = pipe_transfer_map(pipe, transfer);
+
+
+      /* Put image into texture transfer.
+       * Note that the image is actually going to be upside down in
+       * the texture.  We deal with that with texcoords.
+       */
+      success = _mesa_texstore(ctx, 2,           /* dims */
+                               baseFormat,       /* baseInternalFormat */
+                               mformat,          /* gl_format */
+                               dest,             /* dest */
+                               0, 0, 0,          /* dstX/Y/Zoffset */
+                               transfer->stride, /* dstRowStride, bytes */
+                               &dstImageOffsets, /* dstImageOffsets */
+                               width, height, 1, /* size */
+                               format, type,     /* src format/type */
+                               pixels,           /* data source */
+                               unpack);
+
+      /* unmap */
+      pipe_transfer_unmap(pipe, transfer);
+      pipe->transfer_destroy(pipe, transfer);
+
+      assert(success);
+
+      /* restore */
+      ctx->_ImageTransferState = imageTransferStateSave;
+   }
+
+   _mesa_unmap_pbo_source(ctx, unpack);
+
+   return pt;
+}
+
+
+/**
+ * Draw quad with texcoords and optional color.
+ * Coords are gallium window coords with y=0=top.
+ * \param color  may be null
+ * \param invertTex  if true, flip texcoords vertically
+ */
+static void
+draw_quad(struct gl_context *ctx, GLfloat x0, GLfloat y0, GLfloat z,
+          GLfloat x1, GLfloat y1, const GLfloat *color,
+          GLboolean invertTex, GLfloat maxXcoord, GLfloat maxYcoord)
+{
+   struct st_context *st = st_context(ctx);
+   struct pipe_context *pipe = st->pipe;
+   GLfloat verts[4][3][4]; /* four verts, three attribs, XYZW */
+
+   /* setup vertex data */
+   {
+      const struct gl_framebuffer *fb = st->ctx->DrawBuffer;
+      const GLfloat fb_width = (GLfloat) fb->Width;
+      const GLfloat fb_height = (GLfloat) fb->Height;
+      const GLfloat clip_x0 = x0 / fb_width * 2.0f - 1.0f;
+      const GLfloat clip_y0 = y0 / fb_height * 2.0f - 1.0f;
+      const GLfloat clip_x1 = x1 / fb_width * 2.0f - 1.0f;
+      const GLfloat clip_y1 = y1 / fb_height * 2.0f - 1.0f;
+      const GLfloat sLeft = 0.0f, sRight = maxXcoord;
+      const GLfloat tTop = invertTex ? maxYcoord : 0.0f;
+      const GLfloat tBot = invertTex ? 0.0f : maxYcoord;
+      GLuint i;
+
+      /* upper-left */
+      verts[0][0][0] = clip_x0;    /* v[0].attr[0].x */
+      verts[0][0][1] = clip_y0;    /* v[0].attr[0].y */
+
+      /* upper-right */
+      verts[1][0][0] = clip_x1;
+      verts[1][0][1] = clip_y0;
+
+      /* lower-right */
+      verts[2][0][0] = clip_x1;
+      verts[2][0][1] = clip_y1;
+
+      /* lower-left */
+      verts[3][0][0] = clip_x0;
+      verts[3][0][1] = clip_y1;
+
+      verts[0][1][0] = sLeft; /* v[0].attr[1].S */
+      verts[0][1][1] = tTop;  /* v[0].attr[1].T */
+      verts[1][1][0] = sRight;
+      verts[1][1][1] = tTop;
+      verts[2][1][0] = sRight;
+      verts[2][1][1] = tBot;
+      verts[3][1][0] = sLeft;
+      verts[3][1][1] = tBot;
+
+      /* same for all verts: */
+      if (color) {
+         for (i = 0; i < 4; i++) {
+            verts[i][0][2] = z;         /* v[i].attr[0].z */
+            verts[i][0][3] = 1.0f;      /* v[i].attr[0].w */
+            verts[i][2][0] = color[0];  /* v[i].attr[2].r */
+            verts[i][2][1] = color[1];  /* v[i].attr[2].g */
+            verts[i][2][2] = color[2];  /* v[i].attr[2].b */
+            verts[i][2][3] = color[3];  /* v[i].attr[2].a */
+            verts[i][1][2] = 0.0f;      /* v[i].attr[1].R */
+            verts[i][1][3] = 1.0f;      /* v[i].attr[1].Q */
+         }
+      }
+      else {
+         for (i = 0; i < 4; i++) {
+            verts[i][0][2] = z;    /*Z*/
+            verts[i][0][3] = 1.0f; /*W*/
+            verts[i][1][2] = 0.0f; /*R*/
+            verts[i][1][3] = 1.0f; /*Q*/
+         }
+      }
+   }
+
+   {
+      struct pipe_resource *buf;
+
+      /* allocate/load buffer object with vertex data */
+      buf = pipe_buffer_create(pipe->screen,
+			       PIPE_BIND_VERTEX_BUFFER,
+			       PIPE_USAGE_STATIC,
+                               sizeof(verts));
+      pipe_buffer_write(st->pipe, buf, 0, sizeof(verts), verts);
+
+      util_draw_vertex_buffer(pipe, st->cso_context, buf, 0,
+                              PIPE_PRIM_QUADS,
+                              4,  /* verts */
+                              3); /* attribs/vert */
+      pipe_resource_reference(&buf, NULL);
+   }
+}
+
+
+
+static void
+draw_textured_quad(struct gl_context *ctx, GLint x, GLint y, GLfloat z,
+                   GLsizei width, GLsizei height,
+                   GLfloat zoomX, GLfloat zoomY,
+                   struct pipe_sampler_view **sv,
+                   int num_sampler_view,
+                   void *driver_vp,
+                   void *driver_fp,
+                   const GLfloat *color,
+                   GLboolean invertTex,
+                   GLboolean write_depth, GLboolean write_stencil)
+{
+   struct st_context *st = st_context(ctx);
+   struct pipe_context *pipe = st->pipe;
+   struct cso_context *cso = st->cso_context;
+   GLfloat x0, y0, x1, y1;
+   GLsizei maxSize;
+   boolean normalized = sv[0]->texture->target != PIPE_TEXTURE_RECT;
+
+   /* limit checks */
+   /* XXX if DrawPixels image is larger than max texture size, break
+    * it up into chunks.
+    */
+   maxSize = 1 << (pipe->screen->get_param(pipe->screen,
+                                        PIPE_CAP_MAX_TEXTURE_2D_LEVELS) - 1);
+   assert(width <= maxSize);
+   assert(height <= maxSize);
+
+   cso_save_rasterizer(cso);
+   cso_save_viewport(cso);
+   cso_save_samplers(cso);
+   cso_save_fragment_sampler_views(cso);
+   cso_save_fragment_shader(cso);
+   cso_save_vertex_shader(cso);
+   cso_save_vertex_elements(cso);
+   cso_save_vertex_buffers(cso);
+   if (write_stencil) {
+      cso_save_depth_stencil_alpha(cso);
+      cso_save_blend(cso);
+   }
+
+   /* rasterizer state: just scissor */
+   {
+      struct pipe_rasterizer_state rasterizer;
+      memset(&rasterizer, 0, sizeof(rasterizer));
+      rasterizer.gl_rasterization_rules = 1;
+      rasterizer.scissor = ctx->Scissor.Enabled;
+      cso_set_rasterizer(cso, &rasterizer);
+   }
+
+   if (write_stencil) {
+      /* Stencil writing bypasses the normal fragment pipeline to
+       * disable color writing and set stencil test to always pass.
+       */
+      struct pipe_depth_stencil_alpha_state dsa;
+      struct pipe_blend_state blend;
+
+      /* depth/stencil */
+      memset(&dsa, 0, sizeof(dsa));
+      dsa.stencil[0].enabled = 1;
+      dsa.stencil[0].func = PIPE_FUNC_ALWAYS;
+      dsa.stencil[0].writemask = ctx->Stencil.WriteMask[0] & 0xff;
+      dsa.stencil[0].zpass_op = PIPE_STENCIL_OP_REPLACE;
+      if (write_depth) {
+         /* writing depth+stencil: depth test always passes */
+         dsa.depth.enabled = 1;
+         dsa.depth.writemask = ctx->Depth.Mask;
+         dsa.depth.func = PIPE_FUNC_ALWAYS;
+      }
+      cso_set_depth_stencil_alpha(cso, &dsa);
+
+      /* blend (colormask) */
+      memset(&blend, 0, sizeof(blend));
+      cso_set_blend(cso, &blend);
+   }
+
+   /* fragment shader state: TEX lookup program */
+   cso_set_fragment_shader_handle(cso, driver_fp);
+
+   /* vertex shader state: position + texcoord pass-through */
+   cso_set_vertex_shader_handle(cso, driver_vp);
+
+
+   /* texture sampling state: */
+   {
+      struct pipe_sampler_state sampler;
+      memset(&sampler, 0, sizeof(sampler));
+      sampler.wrap_s = PIPE_TEX_WRAP_CLAMP;
+      sampler.wrap_t = PIPE_TEX_WRAP_CLAMP;
+      sampler.wrap_r = PIPE_TEX_WRAP_CLAMP;
+      sampler.min_img_filter = PIPE_TEX_FILTER_NEAREST;
+      sampler.min_mip_filter = PIPE_TEX_MIPFILTER_NONE;
+      sampler.mag_img_filter = PIPE_TEX_FILTER_NEAREST;
+      sampler.normalized_coords = normalized;
+
+      cso_single_sampler(cso, 0, &sampler);
+      if (num_sampler_view > 1) {
+         cso_single_sampler(cso, 1, &sampler);
+      }
+      cso_single_sampler_done(cso);
+   }
+
+   /* viewport state: viewport matching window dims */
+   {
+      const float w = (float) ctx->DrawBuffer->Width;
+      const float h = (float) ctx->DrawBuffer->Height;
+      struct pipe_viewport_state vp;
+      vp.scale[0] =  0.5f * w;
+      vp.scale[1] = -0.5f * h;
+      vp.scale[2] = 0.5f;
+      vp.scale[3] = 1.0f;
+      vp.translate[0] = 0.5f * w;
+      vp.translate[1] = 0.5f * h;
+      vp.translate[2] = 0.5f;
+      vp.translate[3] = 0.0f;
+      cso_set_viewport(cso, &vp);
+   }
+
+   cso_set_vertex_elements(cso, 3, st->velems_util_draw);
+
+   /* texture state: */
+   cso_set_fragment_sampler_views(cso, num_sampler_view, sv);
+
+   /* Compute Gallium window coords (y=0=top) with pixel zoom.
+    * Recall that these coords are transformed by the current
+    * vertex shader and viewport transformation.
+    */
+   if (st_fb_orientation(ctx->DrawBuffer) == Y_0_BOTTOM) {
+      y = ctx->DrawBuffer->Height - (int) (y + height * ctx->Pixel.ZoomY);
+      invertTex = !invertTex;
+   }
+
+   x0 = (GLfloat) x;
+   x1 = x + width * ctx->Pixel.ZoomX;
+   y0 = (GLfloat) y;
+   y1 = y + height * ctx->Pixel.ZoomY;
+
+   /* convert Z from [0,1] to [-1,-1] to match viewport Z scale/bias */
+   z = z * 2.0 - 1.0;
+
+   draw_quad(ctx, x0, y0, z, x1, y1, color, invertTex,
+             normalized ? ((GLfloat) width / sv[0]->texture->width0) : (GLfloat)width,
+             normalized ? ((GLfloat) height / sv[0]->texture->height0) : (GLfloat)height);
+
+   /* restore state */
+   cso_restore_rasterizer(cso);
+   cso_restore_viewport(cso);
+   cso_restore_samplers(cso);
+   cso_restore_fragment_sampler_views(cso);
+   cso_restore_fragment_shader(cso);
+   cso_restore_vertex_shader(cso);
+   cso_restore_vertex_elements(cso);
+   cso_restore_vertex_buffers(cso);
+   if (write_stencil) {
+      cso_restore_depth_stencil_alpha(cso);
+      cso_restore_blend(cso);
+   }
+}
+
+
+/**
+ * Software fallback to do glDrawPixels(GL_STENCIL_INDEX) when we
+ * can't use a fragment shader to write stencil values.
+ */
+static void
+draw_stencil_pixels(struct gl_context *ctx, GLint x, GLint y,
+                    GLsizei width, GLsizei height, GLenum format, GLenum type,
+                    const struct gl_pixelstore_attrib *unpack,
+                    const GLvoid *pixels)
+{
+   struct st_context *st = st_context(ctx);
+   struct pipe_context *pipe = st->pipe;
+   struct st_renderbuffer *strb;
+   enum pipe_transfer_usage usage;
+   struct pipe_transfer *pt;
+   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0 || ctx->Pixel.ZoomY != 1.0;
+   GLint skipPixels;
+   ubyte *stmap;
+   struct gl_pixelstore_attrib clippedUnpack = *unpack;
+
+   if (!zoom) {
+      if (!_mesa_clip_drawpixels(ctx, &x, &y, &width, &height,
+                                 &clippedUnpack)) {
+         /* totally clipped */
+         return;
+      }
+   }
+
+   strb = st_renderbuffer(ctx->DrawBuffer->
+                          Attachment[BUFFER_STENCIL].Renderbuffer);
+
+   if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
+      y = ctx->DrawBuffer->Height - y - height;
+   }
+
+   if(format != GL_DEPTH_STENCIL && 
+      util_format_get_component_bits(strb->format,
+                                     UTIL_FORMAT_COLORSPACE_ZS, 0) != 0)
+      usage = PIPE_TRANSFER_READ_WRITE;
+   else
+      usage = PIPE_TRANSFER_WRITE;
+
+   pt = pipe_get_transfer(st_context(ctx)->pipe, strb->texture, 0, 0,
+                                     usage, x, y,
+                                     width, height);
+
+   stmap = pipe_transfer_map(pipe, pt);
+
+   pixels = _mesa_map_pbo_source(ctx, &clippedUnpack, pixels);
+   assert(pixels);
+
+   /* if width > MAX_WIDTH, have to process image in chunks */
+   skipPixels = 0;
+   while (skipPixels < width) {
+      const GLint spanX = skipPixels;
+      const GLint spanWidth = MIN2(width - skipPixels, MAX_WIDTH);
+      GLint row;
+      for (row = 0; row < height; row++) {
+         GLubyte sValues[MAX_WIDTH];
+         GLuint zValues[MAX_WIDTH];
+         GLenum destType = GL_UNSIGNED_BYTE;
+         const GLvoid *source = _mesa_image_address2d(&clippedUnpack, pixels,
+                                                      width, height,
+                                                      format, type,
+                                                      row, skipPixels);
+         _mesa_unpack_stencil_span(ctx, spanWidth, destType, sValues,
+                                   type, source, &clippedUnpack,
+                                   ctx->_ImageTransferState);
+
+         if (format == GL_DEPTH_STENCIL) {
+            _mesa_unpack_depth_span(ctx, spanWidth, GL_UNSIGNED_INT, zValues,
+                                    (1 << 24) - 1, type, source,
+                                    &clippedUnpack);
+         }
+
+         if (zoom) {
+            _mesa_problem(ctx, "Gallium glDrawPixels(GL_STENCIL) with "
+                          "zoom not complete");
+         }
+
+         {
+            GLint spanY;
+
+            if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
+               spanY = height - row - 1;
+            }
+            else {
+               spanY = row;
+            }
+
+            /* now pack the stencil (and Z) values in the dest format */
+            switch (pt->resource->format) {
+            case PIPE_FORMAT_S8_USCALED:
+               {
+                  ubyte *dest = stmap + spanY * pt->stride + spanX;
+                  assert(usage == PIPE_TRANSFER_WRITE);
+                  memcpy(dest, sValues, spanWidth);
+               }
+               break;
+            case PIPE_FORMAT_Z24_UNORM_S8_USCALED:
+               if (format == GL_DEPTH_STENCIL) {
+                  uint *dest = (uint *) (stmap + spanY * pt->stride + spanX*4);
+                  GLint k;
+                  assert(usage == PIPE_TRANSFER_WRITE);
+                  for (k = 0; k < spanWidth; k++) {
+                     dest[k] = zValues[k] | (sValues[k] << 24);
+                  }
+               }
+               else {
+                  uint *dest = (uint *) (stmap + spanY * pt->stride + spanX*4);
+                  GLint k;
+                  assert(usage == PIPE_TRANSFER_READ_WRITE);
+                  for (k = 0; k < spanWidth; k++) {
+                     dest[k] = (dest[k] & 0xffffff) | (sValues[k] << 24);
+                  }
+               }
+               break;
+            case PIPE_FORMAT_S8_USCALED_Z24_UNORM:
+               if (format == GL_DEPTH_STENCIL) {
+                  uint *dest = (uint *) (stmap + spanY * pt->stride + spanX*4);
+                  GLint k;
+                  assert(usage == PIPE_TRANSFER_WRITE);
+                  for (k = 0; k < spanWidth; k++) {
+                     dest[k] = (zValues[k] << 8) | (sValues[k] & 0xff);
+                  }
+               }
+               else {
+                  uint *dest = (uint *) (stmap + spanY * pt->stride + spanX*4);
+                  GLint k;
+                  assert(usage == PIPE_TRANSFER_READ_WRITE);
+                  for (k = 0; k < spanWidth; k++) {
+                     dest[k] = (dest[k] & 0xffffff00) | (sValues[k] & 0xff);
+                  }
+               }
+               break;
+            default:
+               assert(0);
+            }
+         }
+      }
+      skipPixels += spanWidth;
+   }
+
+   _mesa_unmap_pbo_source(ctx, &clippedUnpack);
+
+   /* unmap the stencil buffer */
+   pipe_transfer_unmap(pipe, pt);
+   pipe->transfer_destroy(pipe, pt);
+}
+
+
+/**
+ * Get fragment program variant for a glDrawPixels or glCopyPixels
+ * command for RGBA data.
+ */
+static struct st_fp_variant *
+get_color_fp_variant(struct st_context *st)
+{
+   struct gl_context *ctx = st->ctx;
+   struct st_fp_variant_key key;
+   struct st_fp_variant *fpv;
+
+   memset(&key, 0, sizeof(key));
+
+   key.st = st;
+   key.drawpixels = 1;
+   key.scaleAndBias = (ctx->Pixel.RedBias != 0.0 ||
+                       ctx->Pixel.RedScale != 1.0 ||
+                       ctx->Pixel.GreenBias != 0.0 ||
+                       ctx->Pixel.GreenScale != 1.0 ||
+                       ctx->Pixel.BlueBias != 0.0 ||
+                       ctx->Pixel.BlueScale != 1.0 ||
+                       ctx->Pixel.AlphaBias != 0.0 ||
+                       ctx->Pixel.AlphaScale != 1.0);
+   key.pixelMaps = ctx->Pixel.MapColorFlag;
+
+   fpv = st_get_fp_variant(st, st->fp, &key);
+
+   return fpv;
+}
+
+
+/**
+ * Get fragment program variant for a glDrawPixels or glCopyPixels
+ * command for depth/stencil data.
+ */
+static struct st_fp_variant *
+get_depth_stencil_fp_variant(struct st_context *st, GLboolean write_depth,
+                             GLboolean write_stencil)
+{
+   struct st_fp_variant_key key;
+   struct st_fp_variant *fpv;
+
+   memset(&key, 0, sizeof(key));
+
+   key.st = st;
+   key.drawpixels = 1;
+   key.drawpixels_z = write_depth;
+   key.drawpixels_stencil = write_stencil;
+
+   fpv = st_get_fp_variant(st, st->fp, &key);
+
+   return fpv;
+}
+
+
+/**
+ * Called via ctx->Driver.DrawPixels()
+ */
+static void
+st_DrawPixels(struct gl_context *ctx, GLint x, GLint y,
+              GLsizei width, GLsizei height,
+              GLenum format, GLenum type,
+              const struct gl_pixelstore_attrib *unpack, const GLvoid *pixels)
+{
+   void *driver_vp, *driver_fp;
+   struct st_context *st = st_context(ctx);
+   const GLfloat *color;
+   struct pipe_context *pipe = st->pipe;
+   GLboolean write_stencil = GL_FALSE, write_depth = GL_FALSE;
+   struct pipe_sampler_view *sv[2];
+   int num_sampler_view = 1;
+   enum pipe_format stencil_format = PIPE_FORMAT_NONE;
+   struct st_fp_variant *fpv;
+
+   if (format == GL_DEPTH_STENCIL)
+      write_stencil = write_depth = GL_TRUE;
+   else if (format == GL_STENCIL_INDEX)
+      write_stencil = GL_TRUE;
+   else if (format == GL_DEPTH_COMPONENT)
+      write_depth = GL_TRUE;
+
+   if (write_stencil) {
+      enum pipe_format tex_format;
+      /* can we write to stencil if not fallback */
+      if (!pipe->screen->get_param(pipe->screen, PIPE_CAP_SHADER_STENCIL_EXPORT))
+	 goto stencil_fallback;
+      
+      tex_format = st_choose_format(st->pipe->screen, base_format(format),
+                                    PIPE_TEXTURE_2D,
+				    0, PIPE_BIND_SAMPLER_VIEW);
+      if (tex_format == PIPE_FORMAT_Z24_UNORM_S8_USCALED)
+	 stencil_format = PIPE_FORMAT_X24S8_USCALED;
+      else if (tex_format == PIPE_FORMAT_S8_USCALED_Z24_UNORM)
+	 stencil_format = PIPE_FORMAT_S8X24_USCALED;
+      else
+	 stencil_format = PIPE_FORMAT_S8_USCALED;
+      if (stencil_format == PIPE_FORMAT_NONE)
+	 goto stencil_fallback;
+   }
+
+   /* Mesa state should be up to date by now */
+   assert(ctx->NewState == 0x0);
+
+   st_validate_state(st);
+
+   /*
+    * Get vertex/fragment shaders
+    */
+   if (write_depth || write_stencil) {
+      fpv = get_depth_stencil_fp_variant(st, write_depth, write_stencil);
+
+      driver_fp = fpv->driver_shader;
+
+      driver_vp = make_passthrough_vertex_shader(st, GL_TRUE);
+
+      color = ctx->Current.RasterColor;
+   }
+   else {
+      fpv = get_color_fp_variant(st);
+
+      driver_fp = fpv->driver_shader;
+
+      driver_vp = make_passthrough_vertex_shader(st, GL_FALSE);
+
+      color = NULL;
+      if (st->pixel_xfer.pixelmap_enabled) {
+	  sv[1] = st->pixel_xfer.pixelmap_sampler_view;
+	  num_sampler_view++;
+      }
+   }
+
+   /* update fragment program constants */
+   st_upload_constants(st, fpv->parameters, PIPE_SHADER_FRAGMENT);
+
+   /* draw with textured quad */
+   {
+      struct pipe_resource *pt
+         = make_texture(st, width, height, format, type, unpack, pixels);
+      if (pt) {
+         sv[0] = st_create_texture_sampler_view(st->pipe, pt);
+
+         if (sv[0]) {
+	    if (write_stencil) {
+	       sv[1] = st_create_texture_sampler_view_format(st->pipe, pt,
+                                                             stencil_format);
+	       num_sampler_view++;
+	    }
+
+            draw_textured_quad(ctx, x, y, ctx->Current.RasterPos[2],
+                               width, height,
+                               ctx->Pixel.ZoomX, ctx->Pixel.ZoomY,
+                               sv,
+                               num_sampler_view,
+                               driver_vp,
+                               driver_fp,
+                               color, GL_FALSE, write_depth, write_stencil);
+            pipe_sampler_view_reference(&sv[0], NULL);
+            if (num_sampler_view > 1)
+               pipe_sampler_view_reference(&sv[1], NULL);
+         }
+         pipe_resource_reference(&pt, NULL);
+      }
+   }
+   return;
+
+stencil_fallback:
+   draw_stencil_pixels(ctx, x, y, width, height, format, type,
+		       unpack, pixels);
+}
+
+
+
+/**
+ * Software fallback for glCopyPixels(GL_STENCIL).
+ */
+static void
+copy_stencil_pixels(struct gl_context *ctx, GLint srcx, GLint srcy,
+                    GLsizei width, GLsizei height,
+                    GLint dstx, GLint dsty)
+{
+   struct st_renderbuffer *rbDraw;
+   struct pipe_context *pipe = st_context(ctx)->pipe;
+   enum pipe_transfer_usage usage;
+   struct pipe_transfer *ptDraw;
+   ubyte *drawMap;
+   ubyte *buffer;
+   int i;
+
+   buffer = malloc(width * height * sizeof(ubyte));
+   if (!buffer) {
+      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels(stencil)");
+      return;
+   }
+
+   /* Get the dest renderbuffer.  If there's a wrapper, use the
+    * underlying renderbuffer.
+    */
+   rbDraw = st_renderbuffer(ctx->DrawBuffer->_StencilBuffer);
+   if (rbDraw->Base.Wrapped)
+      rbDraw = st_renderbuffer(rbDraw->Base.Wrapped);
+
+   /* this will do stencil pixel transfer ops */
+   st_read_stencil_pixels(ctx, srcx, srcy, width, height,
+                          GL_STENCIL_INDEX, GL_UNSIGNED_BYTE,
+                          &ctx->DefaultPacking, buffer);
+
+   if (0) {
+      /* debug code: dump stencil values */
+      GLint row, col;
+      for (row = 0; row < height; row++) {
+         printf("%3d: ", row);
+         for (col = 0; col < width; col++) {
+            printf("%02x ", buffer[col + row * width]);
+         }
+         printf("\n");
+      }
+   }
+
+   if (util_format_get_component_bits(rbDraw->format,
+                                     UTIL_FORMAT_COLORSPACE_ZS, 0) != 0)
+      usage = PIPE_TRANSFER_READ_WRITE;
+   else
+      usage = PIPE_TRANSFER_WRITE;
+
+   if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
+      dsty = rbDraw->Base.Height - dsty - height;
+   }
+
+   ptDraw = pipe_get_transfer(st_context(ctx)->pipe,
+                              rbDraw->texture, 0, 0,
+                              usage, dstx, dsty,
+                              width, height);
+
+   assert(util_format_get_blockwidth(ptDraw->resource->format) == 1);
+   assert(util_format_get_blockheight(ptDraw->resource->format) == 1);
+
+   /* map the stencil buffer */
+   drawMap = pipe_transfer_map(pipe, ptDraw);
+
+   /* draw */
+   /* XXX PixelZoom not handled yet */
+   for (i = 0; i < height; i++) {
+      ubyte *dst;
+      const ubyte *src;
+      int y;
+
+      y = i;
+
+      if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
+         y = height - y - 1;
+      }
+
+      dst = drawMap + y * ptDraw->stride;
+      src = buffer + i * width;
+
+      switch (ptDraw->resource->format) {
+      case PIPE_FORMAT_Z24_UNORM_S8_USCALED:
+         {
+            uint *dst4 = (uint *) dst;
+            int j;
+            assert(usage == PIPE_TRANSFER_READ_WRITE);
+            for (j = 0; j < width; j++) {
+               *dst4 = (*dst4 & 0xffffff) | (src[j] << 24);
+               dst4++;
+            }
+         }
+         break;
+      case PIPE_FORMAT_S8_USCALED_Z24_UNORM:
+         {
+            uint *dst4 = (uint *) dst;
+            int j;
+            assert(usage == PIPE_TRANSFER_READ_WRITE);
+            for (j = 0; j < width; j++) {
+               *dst4 = (*dst4 & 0xffffff00) | (src[j] & 0xff);
+               dst4++;
+            }
+         }
+         break;
+      case PIPE_FORMAT_S8_USCALED:
+         assert(usage == PIPE_TRANSFER_WRITE);
+         memcpy(dst, src, width);
+         break;
+      default:
+         assert(0);
+      }
+   }
+
+   free(buffer);
+
+   /* unmap the stencil buffer */
+   pipe_transfer_unmap(pipe, ptDraw);
+   pipe->transfer_destroy(pipe, ptDraw);
+}
+
+
+/** Do the src/dest regions overlap? */
+static GLboolean
+regions_overlap(GLint srcX, GLint srcY, GLint dstX, GLint dstY,
+                GLsizei width, GLsizei height)
+{
+   if (srcX + width <= dstX ||
+       dstX + width <= srcX ||
+       srcY + height <= dstY ||
+       dstY + height <= srcY)
+      return GL_FALSE;
+   else
+      return GL_TRUE;
+}
+
+
+/**
+ * Try to do a glCopyPixels for simple cases with a blit by calling
+ * pipe->resource_copy_region().
+ *
+ * We can do this when we're copying color pixels (depth/stencil
+ * eventually) with no pixel zoom, no pixel transfer ops, no
+ * per-fragment ops, the src/dest regions don't overlap and the
+ * src/dest pixel formats are the same.
+ */
+static GLboolean
+blit_copy_pixels(struct gl_context *ctx, GLint srcx, GLint srcy,
+                 GLsizei width, GLsizei height,
+                 GLint dstx, GLint dsty, GLenum type)
+{
+   struct st_context *st = st_context(ctx);
+   struct pipe_context *pipe = st->pipe;
+   struct gl_pixelstore_attrib pack, unpack;
+   GLint readX, readY, readW, readH;
+
+   if (type == GL_COLOR &&
+       ctx->Pixel.ZoomX == 1.0 &&
+       ctx->Pixel.ZoomY == 1.0 &&
+       ctx->_ImageTransferState == 0x0 &&
+       !ctx->Color.BlendEnabled &&
+       !ctx->Color.AlphaEnabled &&
+       !ctx->Depth.Test &&
+       !ctx->Fog.Enabled &&
+       !ctx->Stencil.Enabled &&
+       !ctx->FragmentProgram.Enabled &&
+       !ctx->VertexProgram.Enabled &&
+       !ctx->Shader.CurrentFragmentProgram &&
+       st_fb_orientation(ctx->ReadBuffer) == st_fb_orientation(ctx->DrawBuffer) &&
+       ctx->DrawBuffer->_NumColorDrawBuffers == 1) {
+      struct st_renderbuffer *rbRead, *rbDraw;
+      GLint drawX, drawY;
+
+      /*
+       * Clip the read region against the src buffer bounds.
+       * We'll still allocate a temporary buffer/texture for the original
+       * src region size but we'll only read the region which is on-screen.
+       * This may mean that we draw garbage pixels into the dest region, but
+       * that's expected.
+       */
+      readX = srcx;
+      readY = srcy;
+      readW = width;
+      readH = height;
+      pack = ctx->DefaultPacking;
+      if (!_mesa_clip_readpixels(ctx, &readX, &readY, &readW, &readH, &pack))
+         return GL_TRUE; /* all done */
+
+      /* clip against dest buffer bounds and scissor box */
+      drawX = dstx + pack.SkipPixels;
+      drawY = dsty + pack.SkipRows;
+      unpack = pack;
+      if (!_mesa_clip_drawpixels(ctx, &drawX, &drawY, &readW, &readH, &unpack))
+         return GL_TRUE; /* all done */
+
+      readX = readX - pack.SkipPixels + unpack.SkipPixels;
+      readY = readY - pack.SkipRows + unpack.SkipRows;
+
+      rbRead = st_get_color_read_renderbuffer(ctx);
+      rbDraw = st_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[0]);
+
+      if ((rbRead != rbDraw ||
+           !regions_overlap(readX, readY, drawX, drawY, readW, readH)) &&
+          rbRead->Base.Format == rbDraw->Base.Format) {
+         struct pipe_box srcBox;
+
+         /* flip src/dst position if needed */
+         if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
+            /* both buffers will have the same orientation */
+            readY = ctx->ReadBuffer->Height - readY - readH;
+            drawY = ctx->DrawBuffer->Height - drawY - readH;
+         }
+
+         u_box_2d(readX, readY, readW, readH, &srcBox);
+
+         pipe->resource_copy_region(pipe,
+                                    rbDraw->texture, 0, drawX, drawY, 0,
+                                    rbRead->texture, 0, &srcBox);
+         return GL_TRUE;
+      }
+   }
+
+   return GL_FALSE;
+}
+
+
+static void
+st_CopyPixels(struct gl_context *ctx, GLint srcx, GLint srcy,
+              GLsizei width, GLsizei height,
+              GLint dstx, GLint dsty, GLenum type)
+{
+   struct st_context *st = st_context(ctx);
+   struct pipe_context *pipe = st->pipe;
+   struct pipe_screen *screen = pipe->screen;
+   struct st_renderbuffer *rbRead;
+   void *driver_vp, *driver_fp;
+   struct pipe_resource *pt;
+   struct pipe_sampler_view *sv[2];
+   int num_sampler_view = 1;
+   GLfloat *color;
+   enum pipe_format srcFormat, texFormat;
+   GLboolean invertTex = GL_FALSE;
+   GLint readX, readY, readW, readH;
+   GLuint sample_count;
+   struct gl_pixelstore_attrib pack = ctx->DefaultPacking;
+   struct st_fp_variant *fpv;
+
+   st_validate_state(st);
+
+   if (type == GL_STENCIL) {
+      /* can't use texturing to do stencil */
+      copy_stencil_pixels(ctx, srcx, srcy, width, height, dstx, dsty);
+      return;
+   }
+
+   if (blit_copy_pixels(ctx, srcx, srcy, width, height, dstx, dsty, type))
+      return;
+
+   /*
+    * The subsequent code implements glCopyPixels by copying the source
+    * pixels into a temporary texture that's then applied to a textured quad.
+    * When we draw the textured quad, all the usual per-fragment operations
+    * are handled.
+    */
+
+
+   /*
+    * Get vertex/fragment shaders
+    */
+   if (type == GL_COLOR) {
+      rbRead = st_get_color_read_renderbuffer(ctx);
+      color = NULL;
+
+      fpv = get_color_fp_variant(st);
+      driver_fp = fpv->driver_shader;
+
+      driver_vp = make_passthrough_vertex_shader(st, GL_FALSE);
+
+      if (st->pixel_xfer.pixelmap_enabled) {
+	  sv[1] = st->pixel_xfer.pixelmap_sampler_view;
+	  num_sampler_view++;
+      }
+   }
+   else {
+      assert(type == GL_DEPTH);
+      rbRead = st_renderbuffer(ctx->ReadBuffer->_DepthBuffer);
+      color = ctx->Current.Attrib[VERT_ATTRIB_COLOR0];
+
+      fpv = get_depth_stencil_fp_variant(st, GL_TRUE, GL_FALSE);
+      driver_fp = fpv->driver_shader;
+
+      driver_vp = make_passthrough_vertex_shader(st, GL_TRUE);
+   }
+
+   /* update fragment program constants */
+   st_upload_constants(st, fpv->parameters, PIPE_SHADER_FRAGMENT);
+
+
+   if (rbRead->Base.Wrapped)
+      rbRead = st_renderbuffer(rbRead->Base.Wrapped);
+
+   sample_count = rbRead->texture->nr_samples;
+   /* I believe this would be legal, presumably would need to do a resolve
+      for color, and for depth/stencil spec says to just use one of the
+      depth/stencil samples per pixel? Need some transfer clarifications. */
+   assert(sample_count < 2);
+
+   srcFormat = rbRead->texture->format;
+
+   if (screen->is_format_supported(screen, srcFormat, st->internal_target,
+                                   sample_count,
+                                   PIPE_BIND_SAMPLER_VIEW)) {
+      texFormat = srcFormat;
+   }
+   else {
+      /* srcFormat can't be used as a texture format */
+      if (type == GL_DEPTH) {
+         texFormat = st_choose_format(screen, GL_DEPTH_COMPONENT,
+                                      st->internal_target, sample_count,
+                                      PIPE_BIND_DEPTH_STENCIL);
+         assert(texFormat != PIPE_FORMAT_NONE);
+      }
+      else {
+         /* default color format */
+         texFormat = st_choose_format(screen, GL_RGBA, st->internal_target,
+                                      sample_count, PIPE_BIND_SAMPLER_VIEW);
+         assert(texFormat != PIPE_FORMAT_NONE);
+      }
+   }
+
+   /* Invert src region if needed */
+   if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
+      srcy = ctx->ReadBuffer->Height - srcy - height;
+      invertTex = !invertTex;
+   }
+
+   /* Clip the read region against the src buffer bounds.
+    * We'll still allocate a temporary buffer/texture for the original
+    * src region size but we'll only read the region which is on-screen.
+    * This may mean that we draw garbage pixels into the dest region, but
+    * that's expected.
+    */
+   readX = srcx;
+   readY = srcy;
+   readW = width;
+   readH = height;
+   _mesa_clip_readpixels(ctx, &readX, &readY, &readW, &readH, &pack);
+   readW = MAX2(0, readW);
+   readH = MAX2(0, readH);
+
+   /* alloc temporary texture */
+   pt = alloc_texture(st, width, height, texFormat);
+   if (!pt)
+      return;
+
+   sv[0] = st_create_texture_sampler_view(st->pipe, pt);
+   if (!sv[0]) {
+      pipe_resource_reference(&pt, NULL);
+      return;
+   }
+
+   /* Make temporary texture which is a copy of the src region.
+    */
+   if (srcFormat == texFormat) {
+      struct pipe_box src_box;
+      u_box_2d(readX, readY, readW, readH, &src_box);
+      /* copy source framebuffer surface into mipmap/texture */
+      pipe->resource_copy_region(pipe,
+                                 pt,                                /* dest tex */
+                                 0,
+                                 pack.SkipPixels, pack.SkipRows, 0, /* dest pos */
+                                 rbRead->texture,                   /* src tex */
+                                 0,
+                                 &src_box);
+
+   }
+   else {
+      /* CPU-based fallback/conversion */
+      struct pipe_transfer *ptRead =
+         pipe_get_transfer(st->pipe, rbRead->texture,
+                           0, 0, /* level, layer */
+                           PIPE_TRANSFER_READ,
+                           readX, readY, readW, readH);
+      struct pipe_transfer *ptTex;
+      enum pipe_transfer_usage transfer_usage;
+
+      if (ST_DEBUG & DEBUG_FALLBACK)
+         debug_printf("%s: fallback processing\n", __FUNCTION__);
+
+      if (type == GL_DEPTH && util_format_is_depth_and_stencil(pt->format))
+         transfer_usage = PIPE_TRANSFER_READ_WRITE;
+      else
+         transfer_usage = PIPE_TRANSFER_WRITE;
+
+      ptTex = pipe_get_transfer(st->pipe, pt, 0, 0, transfer_usage,
+                                0, 0, width, height);
+
+      /* copy image from ptRead surface to ptTex surface */
+      if (type == GL_COLOR) {
+         /* alternate path using get/put_tile() */
+         GLfloat *buf = (GLfloat *) malloc(width * height * 4 * sizeof(GLfloat));
+         enum pipe_format readFormat, drawFormat;
+         readFormat = util_format_linear(rbRead->texture->format);
+         drawFormat = util_format_linear(pt->format);
+         pipe_get_tile_rgba_format(pipe, ptRead, 0, 0, readW, readH,
+                                   readFormat, buf);
+         pipe_put_tile_rgba_format(pipe, ptTex, pack.SkipPixels, pack.SkipRows,
+                                   readW, readH, drawFormat, buf);
+         free(buf);
+      }
+      else {
+         /* GL_DEPTH */
+         GLuint *buf = (GLuint *) malloc(width * height * sizeof(GLuint));
+         pipe_get_tile_z(pipe, ptRead, 0, 0, readW, readH, buf);
+         pipe_put_tile_z(pipe, ptTex, pack.SkipPixels, pack.SkipRows,
+                         readW, readH, buf);
+         free(buf);
+      }
+
+      pipe->transfer_destroy(pipe, ptRead);
+      pipe->transfer_destroy(pipe, ptTex);
+   }
+
+   /* OK, the texture 'pt' contains the src image/pixels.  Now draw a
+    * textured quad with that texture.
+    */
+   draw_textured_quad(ctx, dstx, dsty, ctx->Current.RasterPos[2],
+                      width, height, ctx->Pixel.ZoomX, ctx->Pixel.ZoomY,
+                      sv,
+                      num_sampler_view,
+                      driver_vp, 
+                      driver_fp,
+                      color, invertTex, GL_FALSE, GL_FALSE);
+
+   pipe_resource_reference(&pt, NULL);
+   pipe_sampler_view_reference(&sv[0], NULL);
+}
+
+
+
+void st_init_drawpixels_functions(struct dd_function_table *functions)
+{
+   functions->DrawPixels = st_DrawPixels;
+   functions->CopyPixels = st_CopyPixels;
+}
+
+
+void
+st_destroy_drawpix(struct st_context *st)
+{
+   GLuint i;
+
+   for (i = 0; i < Elements(st->drawpix.shaders); i++) {
+      if (st->drawpix.shaders[i])
+         _mesa_reference_fragprog(st->ctx, &st->drawpix.shaders[i], NULL);
+   }
+
+   st_reference_fragprog(st, &st->pixel_xfer.combined_prog, NULL);
+   if (st->drawpix.vert_shaders[0])
+      ureg_free_tokens(st->drawpix.vert_shaders[0]);
+   if (st->drawpix.vert_shaders[1])
+      ureg_free_tokens(st->drawpix.vert_shaders[1]);
+}
+
+#endif /* FEATURE_drawpix */