mesa git update 22 July 2011

1 files changed, 457 insertions, 434 deletions

diff --git a/mesalib/src/gallium/auxiliary/util/u_pstipple.c b/mesalib/src/gallium/auxiliary/util/u_pstipple.c
index 27f72e967..ac0df8c1a 100644
--- a/mesalib/src/gallium/auxiliary/util/u_pstipple.c
+++ b/mesalib/src/gallium/auxiliary/util/u_pstipple.c
@@ -1,434 +1,457 @@
-/**************************************************************************

- * 

- * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.

- * Copyright 2010 VMware, Inc.

- * 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.

- * 

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

-

-/**

- * Polygon stipple helper module.  Drivers/GPUs which don't support polygon

- * stipple natively can use this module to simulate it.

- *

- * Basically, modify fragment shader to sample the 32x32 stipple pattern

- * texture and do a fragment kill for the 'off' bits.

- *

- * This was originally a 'draw' module stage, but since we don't need

- * vertex window coords or anything, it can be a stand-alone utility module.

- *

- * Authors:  Brian Paul

- */

-

-

-#include "pipe/p_context.h"

-#include "pipe/p_defines.h"

-#include "pipe/p_shader_tokens.h"

-#include "util/u_inlines.h"

-

-#include "util/u_format.h"

-#include "util/u_memory.h"

-#include "util/u_pstipple.h"

-#include "util/u_sampler.h"

-

-#include "tgsi/tgsi_transform.h"

-#include "tgsi/tgsi_dump.h"

-

-/** Approx number of new tokens for instructions in pstip_transform_inst() */

-#define NUM_NEW_TOKENS 50

-

-

-static void

-util_pstipple_update_stipple_texture(struct pipe_context *pipe,

-                                     struct pipe_resource *tex,

-                                     const uint32_t pattern[32])

-{

-   static const uint bit31 = 1 << 31;

-   struct pipe_transfer *transfer;

-   ubyte *data;

-   int i, j;

-

-   /* map texture memory */

-   transfer = pipe_get_transfer(pipe, tex, 0, 0,

-                                PIPE_TRANSFER_WRITE, 0, 0, 32, 32);

-   data = pipe->transfer_map(pipe, transfer);

-

-   /*

-    * Load alpha texture.

-    * Note: 0 means keep the fragment, 255 means kill it.

-    * We'll negate the texel value and use KILP which kills if value

-    * is negative.

-    */

-   for (i = 0; i < 32; i++) {

-      for (j = 0; j < 32; j++) {

-         if (pattern[i] & (bit31 >> j)) {

-            /* fragment "on" */

-            data[i * transfer->stride + j] = 0;

-         }

-         else {

-            /* fragment "off" */

-            data[i * transfer->stride + j] = 255;

-         }

-      }

-   }

-

-   /* unmap */

-   pipe->transfer_unmap(pipe, transfer);

-   pipe->transfer_destroy(pipe, transfer);

-}

-

-

-/**

- * Create a 32x32 alpha8 texture that encodes the given stipple pattern.

- */

-struct pipe_resource *

-util_pstipple_create_stipple_texture(struct pipe_context *pipe,

-                                     const uint32_t pattern[32])

-{

-   struct pipe_screen *screen = pipe->screen;

-   struct pipe_resource templat, *tex;

-

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

-   templat.target = PIPE_TEXTURE_2D;

-   templat.format = PIPE_FORMAT_A8_UNORM;

-   templat.last_level = 0;

-   templat.width0 = 32;

-   templat.height0 = 32;

-   templat.depth0 = 1;

-   templat.array_size = 1;

-   templat.bind = PIPE_BIND_SAMPLER_VIEW;

-

-   tex = screen->resource_create(screen, &templat);

-

-   if (tex)

-      util_pstipple_update_stipple_texture(pipe, tex, pattern);

-

-   return tex;

-}

-

-

-/**

- * Create sampler view to sample the stipple texture.

- */

-struct pipe_sampler_view *

-util_pstipple_create_sampler_view(struct pipe_context *pipe,

-                                  struct pipe_resource *tex)

-{

-   struct pipe_sampler_view templat, *sv;

-

-   u_sampler_view_default_template(&templat, tex, tex->format);

-   sv = pipe->create_sampler_view(pipe, tex, &templat);

-

-   return sv;

-}

-

-

-/**

- * Create the sampler CSO that'll be used for stippling.

- */

-void *

-util_pstipple_create_sampler(struct pipe_context *pipe)

-{

-   struct pipe_sampler_state templat;

-   void *s;

-

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

-   templat.wrap_s = PIPE_TEX_WRAP_REPEAT;

-   templat.wrap_t = PIPE_TEX_WRAP_REPEAT;

-   templat.wrap_r = PIPE_TEX_WRAP_REPEAT;

-   templat.min_mip_filter = PIPE_TEX_MIPFILTER_NONE;

-   templat.min_img_filter = PIPE_TEX_FILTER_NEAREST;

-   templat.mag_img_filter = PIPE_TEX_FILTER_NEAREST;

-   templat.normalized_coords = 1;

-   templat.min_lod = 0.0f;

-   templat.max_lod = 0.0f;

-

-   s = pipe->create_sampler_state(pipe, &templat);

-   return s;

-}

-

-

-

-/**

- * Subclass of tgsi_transform_context, used for transforming the

- * user's fragment shader to add the extra texture sample and fragment kill

- * instructions.

- */

-struct pstip_transform_context {

-   struct tgsi_transform_context base;

-   uint tempsUsed;  /**< bitmask */

-   int wincoordInput;

-   int maxInput;

-   uint samplersUsed;  /**< bitfield of samplers used */

-   int freeSampler;  /** an available sampler for the pstipple */

-   int texTemp;  /**< temp registers */

-   int numImmed;

-   boolean firstInstruction;

-};

-

-

-/**

- * TGSI declaration transform callback.

- * Look for a free sampler, a free input attrib, and two free temp regs.

- */

-static void

-pstip_transform_decl(struct tgsi_transform_context *ctx,

-                     struct tgsi_full_declaration *decl)

-{

-   struct pstip_transform_context *pctx =

-      (struct pstip_transform_context *) ctx;

-

-   if (decl->Declaration.File == TGSI_FILE_SAMPLER) {

-      uint i;

-      for (i = decl->Range.First;

-           i <= decl->Range.Last; i++) {

-         pctx->samplersUsed |= 1 << i;

-      }

-   }

-   else if (decl->Declaration.File == TGSI_FILE_INPUT) {

-      pctx->maxInput = MAX2(pctx->maxInput, (int) decl->Range.Last);

-      if (decl->Semantic.Name == TGSI_SEMANTIC_POSITION)

-         pctx->wincoordInput = (int) decl->Range.First;

-   }

-   else if (decl->Declaration.File == TGSI_FILE_TEMPORARY) {

-      uint i;

-      for (i = decl->Range.First;

-           i <= decl->Range.Last; i++) {

-         pctx->tempsUsed |= (1 << i);

-      }

-   }

-

-   ctx->emit_declaration(ctx, decl);

-}

-

-

-static void

-pstip_transform_immed(struct tgsi_transform_context *ctx,

-                      struct tgsi_full_immediate *immed)

-{

-   struct pstip_transform_context *pctx =

-      (struct pstip_transform_context *) ctx;

-   pctx->numImmed++;

-}

-

-

-/**

- * Find the lowest zero bit in the given word, or -1 if bitfield is all ones.

- */

-static int

-free_bit(uint bitfield)

-{

-   return ffs(~bitfield) - 1;

-}

-

-

-/**

- * TGSI instruction transform callback.

- * Replace writes to result.color w/ a temp reg.

- * Upon END instruction, insert texture sampling code for antialiasing.

- */

-static void

-pstip_transform_inst(struct tgsi_transform_context *ctx,

-                     struct tgsi_full_instruction *inst)

-{

-   struct pstip_transform_context *pctx =

-      (struct pstip_transform_context *) ctx;

-

-   if (pctx->firstInstruction) {

-      /* emit our new declarations before the first instruction */

-

-      struct tgsi_full_declaration decl;

-      struct tgsi_full_instruction newInst;

-      uint i;

-      int wincoordInput;

-

-      /* find free sampler */

-      pctx->freeSampler = free_bit(pctx->samplersUsed);

-      if (pctx->freeSampler >= PIPE_MAX_SAMPLERS)

-         pctx->freeSampler = PIPE_MAX_SAMPLERS - 1;

-

-      if (pctx->wincoordInput < 0)

-         wincoordInput = pctx->maxInput + 1;

-      else

-         wincoordInput = pctx->wincoordInput;

-

-      /* find one free temp reg */

-      for (i = 0; i < 32; i++) {

-         if ((pctx->tempsUsed & (1 << i)) == 0) {

-            /* found a free temp */

-            if (pctx->texTemp < 0)

-               pctx->texTemp  = i;

-            else

-               break;

-         }

-      }

-      assert(pctx->texTemp >= 0);

-

-      if (pctx->wincoordInput < 0) {

-         /* declare new position input reg */

-         decl = tgsi_default_full_declaration();

-         decl.Declaration.File = TGSI_FILE_INPUT;

-         decl.Declaration.Interpolate = TGSI_INTERPOLATE_LINEAR;

-         decl.Declaration.Semantic = 1;

-         decl.Semantic.Name = TGSI_SEMANTIC_POSITION;

-         decl.Semantic.Index = 0;

-         decl.Range.First = 

-            decl.Range.Last = wincoordInput;

-         ctx->emit_declaration(ctx, &decl);

-      }

-

-      /* declare new sampler */

-      decl = tgsi_default_full_declaration();

-      decl.Declaration.File = TGSI_FILE_SAMPLER;

-      decl.Range.First = 

-      decl.Range.Last = pctx->freeSampler;

-      ctx->emit_declaration(ctx, &decl);

-

-      /* declare new temp regs */

-      decl = tgsi_default_full_declaration();

-      decl.Declaration.File = TGSI_FILE_TEMPORARY;

-      decl.Range.First = 

-      decl.Range.Last = pctx->texTemp;

-      ctx->emit_declaration(ctx, &decl);

-

-      /* emit immediate = {1/32, 1/32, 1, 1}

-       * The index/position of this immediate will be pctx->numImmed

-       */

-      {

-         static const float value[4] = { 1.0/32, 1.0/32, 1.0, 1.0 };

-         struct tgsi_full_immediate immed;

-         uint size = 4;

-         immed = tgsi_default_full_immediate();

-         immed.Immediate.NrTokens = 1 + size; /* one for the token itself */

-         immed.u[0].Float = value[0];

-         immed.u[1].Float = value[1];

-         immed.u[2].Float = value[2];

-         immed.u[3].Float = value[3];

-         ctx->emit_immediate(ctx, &immed);

-      }

-

-      pctx->firstInstruction = FALSE;

-

-

-      /* 

-       * Insert new MUL/TEX/KILP instructions at start of program

-       * Take gl_FragCoord, divide by 32 (stipple size), sample the

-       * texture and kill fragment if needed.

-       *

-       * We'd like to use non-normalized texcoords to index into a RECT

-       * texture, but we can only use REPEAT wrap mode with normalized

-       * texcoords.  Darn.

-       */

-

-      /* XXX invert wincoord if origin isn't lower-left... */

-

-      /* MUL texTemp, INPUT[wincoord], 1/32; */

-      newInst = tgsi_default_full_instruction();

-      newInst.Instruction.Opcode = TGSI_OPCODE_MUL;

-      newInst.Instruction.NumDstRegs = 1;

-      newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;

-      newInst.Dst[0].Register.Index = pctx->texTemp;

-      newInst.Instruction.NumSrcRegs = 2;

-      newInst.Src[0].Register.File = TGSI_FILE_INPUT;

-      newInst.Src[0].Register.Index = wincoordInput;

-      newInst.Src[1].Register.File = TGSI_FILE_IMMEDIATE;

-      newInst.Src[1].Register.Index = pctx->numImmed;

-      ctx->emit_instruction(ctx, &newInst);

-

-      /* TEX texTemp, texTemp, sampler; */

-      newInst = tgsi_default_full_instruction();

-      newInst.Instruction.Opcode = TGSI_OPCODE_TEX;

-      newInst.Instruction.NumDstRegs = 1;

-      newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;

-      newInst.Dst[0].Register.Index = pctx->texTemp;

-      newInst.Instruction.NumSrcRegs = 2;

-      newInst.Instruction.Texture = TRUE;

-      newInst.Texture.Texture = TGSI_TEXTURE_2D;

-      newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;

-      newInst.Src[0].Register.Index = pctx->texTemp;

-      newInst.Src[1].Register.File = TGSI_FILE_SAMPLER;

-      newInst.Src[1].Register.Index = pctx->freeSampler;

-      ctx->emit_instruction(ctx, &newInst);

-

-      /* KIL -texTemp;   # if -texTemp < 0, KILL fragment */

-      newInst = tgsi_default_full_instruction();

-      newInst.Instruction.Opcode = TGSI_OPCODE_KIL;

-      newInst.Instruction.NumDstRegs = 0;

-      newInst.Instruction.NumSrcRegs = 1;

-      newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;

-      newInst.Src[0].Register.Index = pctx->texTemp;

-      newInst.Src[0].Register.Negate = 1;

-      ctx->emit_instruction(ctx, &newInst);

-   }

-

-   /* emit this instruction */

-   ctx->emit_instruction(ctx, inst);

-}

-

-

-/**

- * Given a fragment shader, return a new fragment shader which

- * samples a stipple texture and executes KILL.

- */

-struct pipe_shader_state *

-util_pstipple_create_fragment_shader(struct pipe_context *pipe,

-                                     struct pipe_shader_state *fs,

-                                     unsigned *samplerUnitOut)

-{

-   struct pipe_shader_state *new_fs;

-   struct pstip_transform_context transform;

-   const uint newLen = tgsi_num_tokens(fs->tokens) + NUM_NEW_TOKENS;

-

-   new_fs = MALLOC(sizeof(*new_fs));

-   if (!new_fs)

-      return NULL;

-

-   new_fs->tokens = tgsi_alloc_tokens(newLen);

-   if (!new_fs->tokens) {

-      FREE(new_fs);

-      return NULL;

-   }

-

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

-   transform.wincoordInput = -1;

-   transform.maxInput = -1;

-   transform.texTemp = -1;

-   transform.firstInstruction = TRUE;

-   transform.base.transform_instruction = pstip_transform_inst;

-   transform.base.transform_declaration = pstip_transform_decl;

-   transform.base.transform_immediate = pstip_transform_immed;

-

-   tgsi_transform_shader(fs->tokens,

-                         (struct tgsi_token *) new_fs->tokens,

-                         newLen, &transform.base);

-

-#if 0 /* DEBUG */

-   tgsi_dump(fs->tokens, 0);

-   tgsi_dump(pstip_fs.tokens, 0);

-#endif

-

-   assert(transform.freeSampler < PIPE_MAX_SAMPLERS);

-   *samplerUnitOut = transform.freeSampler;

-

-   return new_fs;

-}

-

+/**************************************************************************
+ * 
+ * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * Copyright 2010 VMware, Inc.
+ * 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.
+ * 
+ **************************************************************************/
+
+/**
+ * Polygon stipple helper module.  Drivers/GPUs which don't support polygon
+ * stipple natively can use this module to simulate it.
+ *
+ * Basically, modify fragment shader to sample the 32x32 stipple pattern
+ * texture and do a fragment kill for the 'off' bits.
+ *
+ * This was originally a 'draw' module stage, but since we don't need
+ * vertex window coords or anything, it can be a stand-alone utility module.
+ *
+ * Authors:  Brian Paul
+ */
+
+
+#include "pipe/p_context.h"
+#include "pipe/p_defines.h"
+#include "pipe/p_shader_tokens.h"
+#include "util/u_inlines.h"
+
+#include "util/u_format.h"
+#include "util/u_memory.h"
+#include "util/u_pstipple.h"
+#include "util/u_sampler.h"
+
+#include "tgsi/tgsi_transform.h"
+#include "tgsi/tgsi_dump.h"
+#include "tgsi/tgsi_scan.h"
+
+/** Approx number of new tokens for instructions in pstip_transform_inst() */
+#define NUM_NEW_TOKENS 50
+
+
+static void
+util_pstipple_update_stipple_texture(struct pipe_context *pipe,
+                                     struct pipe_resource *tex,
+                                     const uint32_t pattern[32])
+{
+   static const uint bit31 = 1 << 31;
+   struct pipe_transfer *transfer;
+   ubyte *data;
+   int i, j;
+
+   /* map texture memory */
+   transfer = pipe_get_transfer(pipe, tex, 0, 0,
+                                PIPE_TRANSFER_WRITE, 0, 0, 32, 32);
+   data = pipe->transfer_map(pipe, transfer);
+
+   /*
+    * Load alpha texture.
+    * Note: 0 means keep the fragment, 255 means kill it.
+    * We'll negate the texel value and use KILP which kills if value
+    * is negative.
+    */
+   for (i = 0; i < 32; i++) {
+      for (j = 0; j < 32; j++) {
+         if (pattern[i] & (bit31 >> j)) {
+            /* fragment "on" */
+            data[i * transfer->stride + j] = 0;
+         }
+         else {
+            /* fragment "off" */
+            data[i * transfer->stride + j] = 255;
+         }
+      }
+   }
+
+   /* unmap */
+   pipe->transfer_unmap(pipe, transfer);
+   pipe->transfer_destroy(pipe, transfer);
+}
+
+
+/**
+ * Create a 32x32 alpha8 texture that encodes the given stipple pattern.
+ */
+struct pipe_resource *
+util_pstipple_create_stipple_texture(struct pipe_context *pipe,
+                                     const uint32_t pattern[32])
+{
+   struct pipe_screen *screen = pipe->screen;
+   struct pipe_resource templat, *tex;
+
+   memset(&templat, 0, sizeof(templat));
+   templat.target = PIPE_TEXTURE_2D;
+   templat.format = PIPE_FORMAT_A8_UNORM;
+   templat.last_level = 0;
+   templat.width0 = 32;
+   templat.height0 = 32;
+   templat.depth0 = 1;
+   templat.array_size = 1;
+   templat.bind = PIPE_BIND_SAMPLER_VIEW;
+
+   tex = screen->resource_create(screen, &templat);
+
+   if (tex)
+      util_pstipple_update_stipple_texture(pipe, tex, pattern);
+
+   return tex;
+}
+
+
+/**
+ * Create sampler view to sample the stipple texture.
+ */
+struct pipe_sampler_view *
+util_pstipple_create_sampler_view(struct pipe_context *pipe,
+                                  struct pipe_resource *tex)
+{
+   struct pipe_sampler_view templat, *sv;
+
+   u_sampler_view_default_template(&templat, tex, tex->format);
+   sv = pipe->create_sampler_view(pipe, tex, &templat);
+
+   return sv;
+}
+
+
+/**
+ * Create the sampler CSO that'll be used for stippling.
+ */
+void *
+util_pstipple_create_sampler(struct pipe_context *pipe)
+{
+   struct pipe_sampler_state templat;
+   void *s;
+
+   memset(&templat, 0, sizeof(templat));
+   templat.wrap_s = PIPE_TEX_WRAP_REPEAT;
+   templat.wrap_t = PIPE_TEX_WRAP_REPEAT;
+   templat.wrap_r = PIPE_TEX_WRAP_REPEAT;
+   templat.min_mip_filter = PIPE_TEX_MIPFILTER_NONE;
+   templat.min_img_filter = PIPE_TEX_FILTER_NEAREST;
+   templat.mag_img_filter = PIPE_TEX_FILTER_NEAREST;
+   templat.normalized_coords = 1;
+   templat.min_lod = 0.0f;
+   templat.max_lod = 0.0f;
+
+   s = pipe->create_sampler_state(pipe, &templat);
+   return s;
+}
+
+
+
+/**
+ * Subclass of tgsi_transform_context, used for transforming the
+ * user's fragment shader to add the extra texture sample and fragment kill
+ * instructions.
+ */
+struct pstip_transform_context {
+   struct tgsi_transform_context base;
+   struct tgsi_shader_info info;
+   uint tempsUsed;  /**< bitmask */
+   int wincoordInput;
+   int maxInput;
+   uint samplersUsed;  /**< bitfield of samplers used */
+   int freeSampler;  /** an available sampler for the pstipple */
+   int texTemp;  /**< temp registers */
+   int numImmed;
+   boolean firstInstruction;
+   uint coordOrigin;
+};
+
+
+/**
+ * TGSI declaration transform callback.
+ * Track samplers used, temps used, inputs used.
+ */
+static void
+pstip_transform_decl(struct tgsi_transform_context *ctx,
+                     struct tgsi_full_declaration *decl)
+{
+   struct pstip_transform_context *pctx =
+      (struct pstip_transform_context *) ctx;
+
+   /* XXX we can use tgsi_shader_info instead of some of this */
+
+   if (decl->Declaration.File == TGSI_FILE_SAMPLER) {
+      uint i;
+      for (i = decl->Range.First; i <= decl->Range.Last; i++) {
+         pctx->samplersUsed |= 1 << i;
+      }
+   }
+   else if (decl->Declaration.File == TGSI_FILE_INPUT) {
+      pctx->maxInput = MAX2(pctx->maxInput, (int) decl->Range.Last);
+      if (decl->Semantic.Name == TGSI_SEMANTIC_POSITION)
+         pctx->wincoordInput = (int) decl->Range.First;
+   }
+   else if (decl->Declaration.File == TGSI_FILE_TEMPORARY) {
+      uint i;
+      for (i = decl->Range.First; i <= decl->Range.Last; i++) {
+         pctx->tempsUsed |= (1 << i);
+      }
+   }
+
+   ctx->emit_declaration(ctx, decl);
+}
+
+
+static void
+pstip_transform_immed(struct tgsi_transform_context *ctx,
+                      struct tgsi_full_immediate *immed)
+{
+   struct pstip_transform_context *pctx =
+      (struct pstip_transform_context *) ctx;
+   pctx->numImmed++;
+}
+
+
+/**
+ * Find the lowest zero bit in the given word, or -1 if bitfield is all ones.
+ */
+static int
+free_bit(uint bitfield)
+{
+   return ffs(~bitfield) - 1;
+}
+
+
+/**
+ * TGSI instruction transform callback.
+ * Before the first instruction, insert our new code to sample the
+ * stipple texture (using the fragment coord register) then kill the
+ * fragment if the stipple texture bit is off.
+ *
+ * Insert:
+ *   declare new registers
+ *   MUL texTemp, INPUT[wincoord], 1/32;
+ *   TEX texTemp, texTemp, sampler;
+ *   KIL -texTemp;   # if -texTemp < 0, KILL fragment
+ *   [...original code...]
+ */
+static void
+pstip_transform_inst(struct tgsi_transform_context *ctx,
+                     struct tgsi_full_instruction *inst)
+{
+   struct pstip_transform_context *pctx =
+      (struct pstip_transform_context *) ctx;
+
+   if (pctx->firstInstruction) {
+      /* emit our new declarations before the first instruction */
+
+      struct tgsi_full_declaration decl;
+      struct tgsi_full_instruction newInst;
+      uint i;
+      int wincoordInput;
+
+      /* find free texture sampler */
+      pctx->freeSampler = free_bit(pctx->samplersUsed);
+      if (pctx->freeSampler >= PIPE_MAX_SAMPLERS)
+         pctx->freeSampler = PIPE_MAX_SAMPLERS - 1;
+
+      if (pctx->wincoordInput < 0)
+         wincoordInput = pctx->maxInput + 1;
+      else
+         wincoordInput = pctx->wincoordInput;
+
+      /* find one free temp register */
+      for (i = 0; i < 32; i++) {
+         if ((pctx->tempsUsed & (1 << i)) == 0) {
+            /* found a free temp */
+            if (pctx->texTemp < 0)
+               pctx->texTemp  = i;
+            else
+               break;
+         }
+      }
+      assert(pctx->texTemp >= 0);
+
+      if (pctx->wincoordInput < 0) {
+         /* declare new position input reg */
+         decl = tgsi_default_full_declaration();
+         decl.Declaration.File = TGSI_FILE_INPUT;
+         decl.Declaration.Interpolate = TGSI_INTERPOLATE_LINEAR;
+         decl.Declaration.Semantic = 1;
+         decl.Semantic.Name = TGSI_SEMANTIC_POSITION;
+         decl.Semantic.Index = 0;
+         decl.Range.First = 
+            decl.Range.Last = wincoordInput;
+         ctx->emit_declaration(ctx, &decl);
+      }
+
+      /* declare new sampler */
+      decl = tgsi_default_full_declaration();
+      decl.Declaration.File = TGSI_FILE_SAMPLER;
+      decl.Range.First = 
+      decl.Range.Last = pctx->freeSampler;
+      ctx->emit_declaration(ctx, &decl);
+
+      /* declare new temp regs */
+      decl = tgsi_default_full_declaration();
+      decl.Declaration.File = TGSI_FILE_TEMPORARY;
+      decl.Range.First = 
+      decl.Range.Last = pctx->texTemp;
+      ctx->emit_declaration(ctx, &decl);
+
+      /* emit immediate = {1/32, 1/32, 1, 1}
+       * The index/position of this immediate will be pctx->numImmed
+       */
+      {
+         static const float value[4] = { 1.0/32, 1.0/32, 1.0, 1.0 };
+         struct tgsi_full_immediate immed;
+         uint size = 4;
+         immed = tgsi_default_full_immediate();
+         immed.Immediate.NrTokens = 1 + size; /* one for the token itself */
+         immed.u[0].Float = value[0];
+         immed.u[1].Float = value[1];
+         immed.u[2].Float = value[2];
+         immed.u[3].Float = value[3];
+         ctx->emit_immediate(ctx, &immed);
+      }
+
+      pctx->firstInstruction = FALSE;
+
+
+      /* 
+       * Insert new MUL/TEX/KILP instructions at start of program
+       * Take gl_FragCoord, divide by 32 (stipple size), sample the
+       * texture and kill fragment if needed.
+       *
+       * We'd like to use non-normalized texcoords to index into a RECT
+       * texture, but we can only use REPEAT wrap mode with normalized
+       * texcoords.  Darn.
+       */
+
+      /* XXX invert wincoord if origin isn't lower-left... */
+
+      /* MUL texTemp, INPUT[wincoord], 1/32; */
+      newInst = tgsi_default_full_instruction();
+      newInst.Instruction.Opcode = TGSI_OPCODE_MUL;
+      newInst.Instruction.NumDstRegs = 1;
+      newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
+      newInst.Dst[0].Register.Index = pctx->texTemp;
+      newInst.Instruction.NumSrcRegs = 2;
+      newInst.Src[0].Register.File = TGSI_FILE_INPUT;
+      newInst.Src[0].Register.Index = wincoordInput;
+      newInst.Src[1].Register.File = TGSI_FILE_IMMEDIATE;
+      newInst.Src[1].Register.Index = pctx->numImmed;
+      ctx->emit_instruction(ctx, &newInst);
+
+      /* TEX texTemp, texTemp, sampler; */
+      newInst = tgsi_default_full_instruction();
+      newInst.Instruction.Opcode = TGSI_OPCODE_TEX;
+      newInst.Instruction.NumDstRegs = 1;
+      newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
+      newInst.Dst[0].Register.Index = pctx->texTemp;
+      newInst.Instruction.NumSrcRegs = 2;
+      newInst.Instruction.Texture = TRUE;
+      newInst.Texture.Texture = TGSI_TEXTURE_2D;
+      newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
+      newInst.Src[0].Register.Index = pctx->texTemp;
+      newInst.Src[1].Register.File = TGSI_FILE_SAMPLER;
+      newInst.Src[1].Register.Index = pctx->freeSampler;
+      ctx->emit_instruction(ctx, &newInst);
+
+      /* KIL -texTemp;   # if -texTemp < 0, KILL fragment */
+      newInst = tgsi_default_full_instruction();
+      newInst.Instruction.Opcode = TGSI_OPCODE_KIL;
+      newInst.Instruction.NumDstRegs = 0;
+      newInst.Instruction.NumSrcRegs = 1;
+      newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
+      newInst.Src[0].Register.Index = pctx->texTemp;
+      newInst.Src[0].Register.Negate = 1;
+      ctx->emit_instruction(ctx, &newInst);
+   }
+
+   /* emit this instruction */
+   ctx->emit_instruction(ctx, inst);
+}
+
+
+/**
+ * Given a fragment shader, return a new fragment shader which
+ * samples a stipple texture and executes KILL.
+ */
+struct pipe_shader_state *
+util_pstipple_create_fragment_shader(struct pipe_context *pipe,
+                                     struct pipe_shader_state *fs,
+                                     unsigned *samplerUnitOut)
+{
+   struct pipe_shader_state *new_fs;
+   struct pstip_transform_context transform;
+   const uint newLen = tgsi_num_tokens(fs->tokens) + NUM_NEW_TOKENS;
+   unsigned i;
+
+   new_fs = MALLOC(sizeof(*new_fs));
+   if (!new_fs)
+      return NULL;
+
+   new_fs->tokens = tgsi_alloc_tokens(newLen);
+   if (!new_fs->tokens) {
+      FREE(new_fs);
+      return NULL;
+   }
+
+   /* Setup shader transformation info/context.
+    */
+   memset(&transform, 0, sizeof(transform));
+   transform.wincoordInput = -1;
+   transform.maxInput = -1;
+   transform.texTemp = -1;
+   transform.firstInstruction = TRUE;
+   transform.coordOrigin = TGSI_FS_COORD_ORIGIN_UPPER_LEFT;
+   transform.base.transform_instruction = pstip_transform_inst;
+   transform.base.transform_declaration = pstip_transform_decl;
+   transform.base.transform_immediate = pstip_transform_immed;
+
+   tgsi_scan_shader(fs->tokens, &transform.info);
+
+   /* find fragment coordinate origin property */
+   for (i = 0; i < transform.info.num_properties; i++) {
+      if (transform.info.properties[i].name == TGSI_PROPERTY_FS_COORD_ORIGIN)
+         transform.coordOrigin = transform.info.properties[i].data[0];
+   }
+
+   tgsi_transform_shader(fs->tokens,
+                         (struct tgsi_token *) new_fs->tokens,
+                         newLen, &transform.base);
+
+#if 0 /* DEBUG */
+   tgsi_dump(fs->tokens, 0);
+   tgsi_dump(new_fs->tokens, 0);
+#endif
+
+   assert(transform.freeSampler < PIPE_MAX_SAMPLERS);
+   *samplerUnitOut = transform.freeSampler;
+
+   return new_fs;
+}
+