diff options
Diffstat (limited to 'mesalib/src/mesa/swrast/s_readpix.c')
-rw-r--r-- | mesalib/src/mesa/swrast/s_readpix.c | 1016 |
1 files changed, 508 insertions, 508 deletions
diff --git a/mesalib/src/mesa/swrast/s_readpix.c b/mesalib/src/mesa/swrast/s_readpix.c index 5c8d7e9c5..23da10dab 100644 --- a/mesalib/src/mesa/swrast/s_readpix.c +++ b/mesalib/src/mesa/swrast/s_readpix.c @@ -1,508 +1,508 @@ -/* - * Mesa 3-D graphics library - * Version: 7.0.3 - * - * Copyright (C) 1999-2007 Brian Paul 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, sublicense, - * 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 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 NONINFRINGEMENT. IN NO EVENT SHALL - * BRIAN PAUL 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. - */ - - -#include "main/glheader.h" -#include "main/colormac.h" -#include "main/feedback.h" -#include "main/formats.h" -#include "main/image.h" -#include "main/imports.h" -#include "main/macros.h" -#include "main/pack.h" -#include "main/pbo.h" -#include "main/state.h" - -#include "s_context.h" -#include "s_depth.h" -#include "s_span.h" -#include "s_stencil.h" - - -/** - * Read pixels for format=GL_DEPTH_COMPONENT. - */ -static void -read_depth_pixels( struct gl_context *ctx, - GLint x, GLint y, - GLsizei width, GLsizei height, - GLenum type, GLvoid *pixels, - const struct gl_pixelstore_attrib *packing ) -{ - struct gl_framebuffer *fb = ctx->ReadBuffer; - struct gl_renderbuffer *rb = fb->_DepthBuffer; - const GLboolean biasOrScale - = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0; - - if (!rb) - return; - - /* clipping should have been done already */ - ASSERT(x >= 0); - ASSERT(y >= 0); - ASSERT(x + width <= (GLint) rb->Width); - ASSERT(y + height <= (GLint) rb->Height); - /* width should never be > MAX_WIDTH since we did clipping earlier */ - ASSERT(width <= MAX_WIDTH); - - if (type == GL_UNSIGNED_SHORT && fb->Visual.depthBits == 16 - && !biasOrScale && !packing->SwapBytes) { - /* Special case: directly read 16-bit unsigned depth values. */ - GLint j; - ASSERT(rb->Format == MESA_FORMAT_Z16); - ASSERT(rb->DataType == GL_UNSIGNED_SHORT); - for (j = 0; j < height; j++, y++) { - void *dest =_mesa_image_address2d(packing, pixels, width, height, - GL_DEPTH_COMPONENT, type, j, 0); - rb->GetRow(ctx, rb, width, x, y, dest); - } - } - else if (type == GL_UNSIGNED_INT && fb->Visual.depthBits == 24 - && !biasOrScale && !packing->SwapBytes) { - /* Special case: directly read 24-bit unsigned depth values. */ - GLint j; - ASSERT(rb->Format == MESA_FORMAT_X8_Z24 || - rb->Format == MESA_FORMAT_S8_Z24 || - rb->Format == MESA_FORMAT_Z24_X8 || - rb->Format == MESA_FORMAT_Z24_S8); - ASSERT(rb->DataType == GL_UNSIGNED_INT || - rb->DataType == GL_UNSIGNED_INT_24_8); - for (j = 0; j < height; j++, y++) { - GLuint *dest = (GLuint *) - _mesa_image_address2d(packing, pixels, width, height, - GL_DEPTH_COMPONENT, type, j, 0); - GLint k; - rb->GetRow(ctx, rb, width, x, y, dest); - /* convert range from 24-bit to 32-bit */ - if (rb->Format == MESA_FORMAT_X8_Z24 || - rb->Format == MESA_FORMAT_S8_Z24) { - for (k = 0; k < width; k++) { - /* Note: put MSByte of 24-bit value into LSByte */ - dest[k] = (dest[k] << 8) | ((dest[k] >> 16) & 0xff); - } - } - else { - for (k = 0; k < width; k++) { - /* Note: fill in LSByte by replication */ - dest[k] = dest[k] | ((dest[k] >> 8) & 0xff); - } - } - } - } - else if (type == GL_UNSIGNED_INT && fb->Visual.depthBits == 32 - && !biasOrScale && !packing->SwapBytes) { - /* Special case: directly read 32-bit unsigned depth values. */ - GLint j; - ASSERT(rb->Format == MESA_FORMAT_Z32); - ASSERT(rb->DataType == GL_UNSIGNED_INT); - for (j = 0; j < height; j++, y++) { - void *dest = _mesa_image_address2d(packing, pixels, width, height, - GL_DEPTH_COMPONENT, type, j, 0); - rb->GetRow(ctx, rb, width, x, y, dest); - } - } - else { - /* General case (slower) */ - GLint j; - for (j = 0; j < height; j++, y++) { - GLfloat depthValues[MAX_WIDTH]; - GLvoid *dest = _mesa_image_address2d(packing, pixels, width, height, - GL_DEPTH_COMPONENT, type, j, 0); - _swrast_read_depth_span_float(ctx, rb, width, x, y, depthValues); - _mesa_pack_depth_span(ctx, width, dest, type, depthValues, packing); - } - } -} - - -/** - * Read pixels for format=GL_STENCIL_INDEX. - */ -static void -read_stencil_pixels( struct gl_context *ctx, - GLint x, GLint y, - GLsizei width, GLsizei height, - GLenum type, GLvoid *pixels, - const struct gl_pixelstore_attrib *packing ) -{ - struct gl_framebuffer *fb = ctx->ReadBuffer; - struct gl_renderbuffer *rb = fb->_StencilBuffer; - GLint j; - - if (!rb) - return; - - /* width should never be > MAX_WIDTH since we did clipping earlier */ - ASSERT(width <= MAX_WIDTH); - - /* process image row by row */ - for (j=0;j<height;j++,y++) { - GLvoid *dest; - GLstencil stencil[MAX_WIDTH]; - - _swrast_read_stencil_span(ctx, rb, width, x, y, stencil); - - dest = _mesa_image_address2d(packing, pixels, width, height, - GL_STENCIL_INDEX, type, j, 0); - - _mesa_pack_stencil_span(ctx, width, type, dest, stencil, packing); - } -} - - - -/** - * Optimized glReadPixels for particular pixel formats when pixel - * scaling, biasing, mapping, etc. are disabled. - * \return GL_TRUE if success, GL_FALSE if unable to do the readpixels - */ -static GLboolean -fast_read_rgba_pixels( struct gl_context *ctx, - GLint x, GLint y, - GLsizei width, GLsizei height, - GLenum format, GLenum type, - GLvoid *pixels, - const struct gl_pixelstore_attrib *packing, - GLbitfield transferOps) -{ - struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer; - - if (!rb) - return GL_FALSE; - - ASSERT(rb->_BaseFormat == GL_RGBA || rb->_BaseFormat == GL_RGB || - rb->_BaseFormat == GL_ALPHA); - - /* clipping should have already been done */ - ASSERT(x + width <= (GLint) rb->Width); - ASSERT(y + height <= (GLint) rb->Height); - - /* check for things we can't handle here */ - if (transferOps || - packing->SwapBytes || - packing->LsbFirst) { - return GL_FALSE; - } - - if (format == GL_RGBA && rb->DataType == type) { - const GLint dstStride = _mesa_image_row_stride(packing, width, - format, type); - GLubyte *dest - = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height, - format, type, 0, 0); - GLint row; - ASSERT(rb->GetRow); - for (row = 0; row < height; row++) { - rb->GetRow(ctx, rb, width, x, y + row, dest); - dest += dstStride; - } - return GL_TRUE; - } - - if (format == GL_RGB && - rb->DataType == GL_UNSIGNED_BYTE && - type == GL_UNSIGNED_BYTE) { - const GLint dstStride = _mesa_image_row_stride(packing, width, - format, type); - GLubyte *dest - = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height, - format, type, 0, 0); - GLint row; - ASSERT(rb->GetRow); - for (row = 0; row < height; row++) { - GLubyte tempRow[MAX_WIDTH][4]; - GLint col; - rb->GetRow(ctx, rb, width, x, y + row, tempRow); - /* convert RGBA to RGB */ - for (col = 0; col < width; col++) { - dest[col * 3 + 0] = tempRow[col][0]; - dest[col * 3 + 1] = tempRow[col][1]; - dest[col * 3 + 2] = tempRow[col][2]; - } - dest += dstStride; - } - return GL_TRUE; - } - - /* not handled */ - return GL_FALSE; -} - - -/** - * When we're using a low-precision color buffer (like 16-bit 5/6/5) - * we have to adjust our color values a bit to pass conformance. - * The problem is when a 5 or 6-bit color value is converted to an 8-bit - * value and then a floating point value, the floating point values don't - * increment uniformly as the 5 or 6-bit value is incremented. - * - * This function adjusts floating point values to compensate. - */ -static void -adjust_colors(const struct gl_framebuffer *fb, GLuint n, GLfloat rgba[][4]) -{ - const GLuint rShift = 8 - fb->Visual.redBits; - const GLuint gShift = 8 - fb->Visual.greenBits; - const GLuint bShift = 8 - fb->Visual.blueBits; - GLfloat rScale = 1.0F / (GLfloat) ((1 << fb->Visual.redBits ) - 1); - GLfloat gScale = 1.0F / (GLfloat) ((1 << fb->Visual.greenBits) - 1); - GLfloat bScale = 1.0F / (GLfloat) ((1 << fb->Visual.blueBits ) - 1); - GLuint i; - - if (fb->Visual.redBits == 0) - rScale = 0; - if (fb->Visual.greenBits == 0) - gScale = 0; - if (fb->Visual.blueBits == 0) - bScale = 0; - - for (i = 0; i < n; i++) { - GLint r, g, b; - /* convert float back to ubyte */ - CLAMPED_FLOAT_TO_UBYTE(r, rgba[i][RCOMP]); - CLAMPED_FLOAT_TO_UBYTE(g, rgba[i][GCOMP]); - CLAMPED_FLOAT_TO_UBYTE(b, rgba[i][BCOMP]); - /* using only the N most significant bits of the ubyte value, convert to - * float in [0,1]. - */ - rgba[i][RCOMP] = (GLfloat) (r >> rShift) * rScale; - rgba[i][GCOMP] = (GLfloat) (g >> gShift) * gScale; - rgba[i][BCOMP] = (GLfloat) (b >> bShift) * bScale; - } -} - - - -/* - * Read R, G, B, A, RGB, L, or LA pixels. - */ -static void -read_rgba_pixels( struct gl_context *ctx, - GLint x, GLint y, - GLsizei width, GLsizei height, - GLenum format, GLenum type, GLvoid *pixels, - const struct gl_pixelstore_attrib *packing ) -{ - SWcontext *swrast = SWRAST_CONTEXT(ctx); - GLbitfield transferOps = ctx->_ImageTransferState; - struct gl_framebuffer *fb = ctx->ReadBuffer; - struct gl_renderbuffer *rb = fb->_ColorReadBuffer; - - if (!rb) - return; - - if (type == GL_FLOAT && ((ctx->Color.ClampReadColor == GL_TRUE) || - (ctx->Color.ClampReadColor == GL_FIXED_ONLY_ARB && - rb->DataType != GL_FLOAT))) - transferOps |= IMAGE_CLAMP_BIT; - - /* Try optimized path first */ - if (fast_read_rgba_pixels(ctx, x, y, width, height, - format, type, pixels, packing, transferOps)) { - return; /* done! */ - } - - /* width should never be > MAX_WIDTH since we did clipping earlier */ - ASSERT(width <= MAX_WIDTH); - - do { - const GLint dstStride - = _mesa_image_row_stride(packing, width, format, type); - GLfloat (*rgba)[4] = swrast->SpanArrays->attribs[FRAG_ATTRIB_COL0]; - GLint row; - GLubyte *dst - = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height, - format, type, 0, 0); - - for (row = 0; row < height; row++, y++) { - - /* Get float rgba pixels */ - _swrast_read_rgba_span(ctx, rb, width, x, y, GL_FLOAT, rgba); - - /* apply fudge factor for shallow color buffers */ - if (fb->Visual.redBits < 8 || - fb->Visual.greenBits < 8 || - fb->Visual.blueBits < 8) { - adjust_colors(fb, width, rgba); - } - - /* pack the row of RGBA pixels into user's buffer */ - _mesa_pack_rgba_span_float(ctx, width, rgba, format, type, dst, - packing, transferOps); - - dst += dstStride; - } - } while (0); -} - - -/** - * Read combined depth/stencil values. - * We'll have already done error checking to be sure the expected - * depth and stencil buffers really exist. - */ -static void -read_depth_stencil_pixels(struct gl_context *ctx, - GLint x, GLint y, - GLsizei width, GLsizei height, - GLenum type, GLvoid *pixels, - const struct gl_pixelstore_attrib *packing ) -{ - const GLboolean scaleOrBias - = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0; - const GLboolean stencilTransfer = ctx->Pixel.IndexShift - || ctx->Pixel.IndexOffset || ctx->Pixel.MapStencilFlag; - struct gl_renderbuffer *depthRb, *stencilRb; - - depthRb = ctx->ReadBuffer->_DepthBuffer; - stencilRb = ctx->ReadBuffer->_StencilBuffer; - - if (!depthRb || !stencilRb) - return; - - depthRb = ctx->ReadBuffer->Attachment[BUFFER_DEPTH].Renderbuffer; - stencilRb = ctx->ReadBuffer->Attachment[BUFFER_STENCIL].Renderbuffer; - - if (depthRb->_BaseFormat == GL_DEPTH_STENCIL_EXT && - stencilRb->_BaseFormat == GL_DEPTH_STENCIL_EXT && - depthRb == stencilRb && - !scaleOrBias && - !stencilTransfer) { - /* This is the ideal case. - * Reading GL_DEPTH_STENCIL pixels from combined depth/stencil buffer. - * Plus, no pixel transfer ops to worry about! - */ - GLint i; - GLint dstStride = _mesa_image_row_stride(packing, width, - GL_DEPTH_STENCIL_EXT, type); - GLubyte *dst = (GLubyte *) _mesa_image_address2d(packing, pixels, - width, height, - GL_DEPTH_STENCIL_EXT, - type, 0, 0); - for (i = 0; i < height; i++) { - depthRb->GetRow(ctx, depthRb, width, x, y + i, dst); - dst += dstStride; - } - } - else { - /* Reading GL_DEPTH_STENCIL pixels from separate depth/stencil buffers, - * or we need pixel transfer. - */ - GLint i; - depthRb = ctx->ReadBuffer->_DepthBuffer; - stencilRb = ctx->ReadBuffer->_StencilBuffer; - - for (i = 0; i < height; i++) { - GLstencil stencilVals[MAX_WIDTH]; - - GLuint *depthStencilDst = (GLuint *) - _mesa_image_address2d(packing, pixels, width, height, - GL_DEPTH_STENCIL_EXT, type, i, 0); - - _swrast_read_stencil_span(ctx, stencilRb, width, - x, y + i, stencilVals); - - if (!scaleOrBias && !stencilTransfer - && ctx->ReadBuffer->Visual.depthBits == 24) { - /* ideal case */ - GLuint zVals[MAX_WIDTH]; /* 24-bit values! */ - GLint j; - ASSERT(depthRb->DataType == GL_UNSIGNED_INT); - /* note, we've already been clipped */ - depthRb->GetRow(ctx, depthRb, width, x, y + i, zVals); - for (j = 0; j < width; j++) { - depthStencilDst[j] = (zVals[j] << 8) | (stencilVals[j] & 0xff); - } - } - else { - /* general case */ - GLfloat depthVals[MAX_WIDTH]; - _swrast_read_depth_span_float(ctx, depthRb, width, x, y + i, - depthVals); - _mesa_pack_depth_stencil_span(ctx, width, depthStencilDst, - depthVals, stencilVals, packing); - } - } - } -} - - - -/** - * Software fallback routine for ctx->Driver.ReadPixels(). - * By time we get here, all error checking will have been done. - */ -void -_swrast_ReadPixels( struct gl_context *ctx, - GLint x, GLint y, GLsizei width, GLsizei height, - GLenum format, GLenum type, - const struct gl_pixelstore_attrib *packing, - GLvoid *pixels ) -{ - SWcontext *swrast = SWRAST_CONTEXT(ctx); - struct gl_pixelstore_attrib clippedPacking = *packing; - - if (ctx->NewState) - _mesa_update_state(ctx); - - /* Need to do swrast_render_start() before clipping or anything else - * since this is where a driver may grab the hw lock and get an updated - * window size. - */ - swrast_render_start(ctx); - - if (swrast->NewState) - _swrast_validate_derived( ctx ); - - /* Do all needed clipping here, so that we can forget about it later */ - if (_mesa_clip_readpixels(ctx, &x, &y, &width, &height, &clippedPacking)) { - - pixels = _mesa_map_pbo_dest(ctx, &clippedPacking, pixels); - - if (pixels) { - switch (format) { - case GL_STENCIL_INDEX: - read_stencil_pixels(ctx, x, y, width, height, type, pixels, - &clippedPacking); - break; - case GL_DEPTH_COMPONENT: - read_depth_pixels(ctx, x, y, width, height, type, pixels, - &clippedPacking); - break; - case GL_DEPTH_STENCIL_EXT: - read_depth_stencil_pixels(ctx, x, y, width, height, type, pixels, - &clippedPacking); - break; - default: - /* all other formats should be color formats */ - read_rgba_pixels(ctx, x, y, width, height, format, type, pixels, - &clippedPacking); - } - - _mesa_unmap_pbo_dest(ctx, &clippedPacking); - } - } - - swrast_render_finish(ctx); -} +/*
+ * Mesa 3-D graphics library
+ * Version: 7.0.3
+ *
+ * Copyright (C) 1999-2007 Brian Paul 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, sublicense,
+ * 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 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 NONINFRINGEMENT. IN NO EVENT SHALL
+ * BRIAN PAUL 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.
+ */
+
+
+#include "main/glheader.h"
+#include "main/colormac.h"
+#include "main/feedback.h"
+#include "main/formats.h"
+#include "main/image.h"
+#include "main/imports.h"
+#include "main/macros.h"
+#include "main/pack.h"
+#include "main/pbo.h"
+#include "main/state.h"
+
+#include "s_context.h"
+#include "s_depth.h"
+#include "s_span.h"
+#include "s_stencil.h"
+
+
+/**
+ * Read pixels for format=GL_DEPTH_COMPONENT.
+ */
+static void
+read_depth_pixels( struct gl_context *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum type, GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing )
+{
+ struct gl_framebuffer *fb = ctx->ReadBuffer;
+ struct gl_renderbuffer *rb = fb->_DepthBuffer;
+ const GLboolean biasOrScale
+ = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0;
+
+ if (!rb)
+ return;
+
+ /* clipping should have been done already */
+ ASSERT(x >= 0);
+ ASSERT(y >= 0);
+ ASSERT(x + width <= (GLint) rb->Width);
+ ASSERT(y + height <= (GLint) rb->Height);
+ /* width should never be > MAX_WIDTH since we did clipping earlier */
+ ASSERT(width <= MAX_WIDTH);
+
+ if (type == GL_UNSIGNED_SHORT && fb->Visual.depthBits == 16
+ && !biasOrScale && !packing->SwapBytes) {
+ /* Special case: directly read 16-bit unsigned depth values. */
+ GLint j;
+ ASSERT(rb->Format == MESA_FORMAT_Z16);
+ ASSERT(rb->DataType == GL_UNSIGNED_SHORT);
+ for (j = 0; j < height; j++, y++) {
+ void *dest =_mesa_image_address2d(packing, pixels, width, height,
+ GL_DEPTH_COMPONENT, type, j, 0);
+ rb->GetRow(ctx, rb, width, x, y, dest);
+ }
+ }
+ else if (type == GL_UNSIGNED_INT && fb->Visual.depthBits == 24
+ && !biasOrScale && !packing->SwapBytes) {
+ /* Special case: directly read 24-bit unsigned depth values. */
+ GLint j;
+ ASSERT(rb->Format == MESA_FORMAT_X8_Z24 ||
+ rb->Format == MESA_FORMAT_S8_Z24 ||
+ rb->Format == MESA_FORMAT_Z24_X8 ||
+ rb->Format == MESA_FORMAT_Z24_S8);
+ ASSERT(rb->DataType == GL_UNSIGNED_INT ||
+ rb->DataType == GL_UNSIGNED_INT_24_8);
+ for (j = 0; j < height; j++, y++) {
+ GLuint *dest = (GLuint *)
+ _mesa_image_address2d(packing, pixels, width, height,
+ GL_DEPTH_COMPONENT, type, j, 0);
+ GLint k;
+ rb->GetRow(ctx, rb, width, x, y, dest);
+ /* convert range from 24-bit to 32-bit */
+ if (rb->Format == MESA_FORMAT_X8_Z24 ||
+ rb->Format == MESA_FORMAT_S8_Z24) {
+ for (k = 0; k < width; k++) {
+ /* Note: put MSByte of 24-bit value into LSByte */
+ dest[k] = (dest[k] << 8) | ((dest[k] >> 16) & 0xff);
+ }
+ }
+ else {
+ for (k = 0; k < width; k++) {
+ /* Note: fill in LSByte by replication */
+ dest[k] = dest[k] | ((dest[k] >> 8) & 0xff);
+ }
+ }
+ }
+ }
+ else if (type == GL_UNSIGNED_INT && fb->Visual.depthBits == 32
+ && !biasOrScale && !packing->SwapBytes) {
+ /* Special case: directly read 32-bit unsigned depth values. */
+ GLint j;
+ ASSERT(rb->Format == MESA_FORMAT_Z32);
+ ASSERT(rb->DataType == GL_UNSIGNED_INT);
+ for (j = 0; j < height; j++, y++) {
+ void *dest = _mesa_image_address2d(packing, pixels, width, height,
+ GL_DEPTH_COMPONENT, type, j, 0);
+ rb->GetRow(ctx, rb, width, x, y, dest);
+ }
+ }
+ else {
+ /* General case (slower) */
+ GLint j;
+ for (j = 0; j < height; j++, y++) {
+ GLfloat depthValues[MAX_WIDTH];
+ GLvoid *dest = _mesa_image_address2d(packing, pixels, width, height,
+ GL_DEPTH_COMPONENT, type, j, 0);
+ _swrast_read_depth_span_float(ctx, rb, width, x, y, depthValues);
+ _mesa_pack_depth_span(ctx, width, dest, type, depthValues, packing);
+ }
+ }
+}
+
+
+/**
+ * Read pixels for format=GL_STENCIL_INDEX.
+ */
+static void
+read_stencil_pixels( struct gl_context *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum type, GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing )
+{
+ struct gl_framebuffer *fb = ctx->ReadBuffer;
+ struct gl_renderbuffer *rb = fb->_StencilBuffer;
+ GLint j;
+
+ if (!rb)
+ return;
+
+ /* width should never be > MAX_WIDTH since we did clipping earlier */
+ ASSERT(width <= MAX_WIDTH);
+
+ /* process image row by row */
+ for (j=0;j<height;j++,y++) {
+ GLvoid *dest;
+ GLstencil stencil[MAX_WIDTH];
+
+ _swrast_read_stencil_span(ctx, rb, width, x, y, stencil);
+
+ dest = _mesa_image_address2d(packing, pixels, width, height,
+ GL_STENCIL_INDEX, type, j, 0);
+
+ _mesa_pack_stencil_span(ctx, width, type, dest, stencil, packing);
+ }
+}
+
+
+
+/**
+ * Optimized glReadPixels for particular pixel formats when pixel
+ * scaling, biasing, mapping, etc. are disabled.
+ * \return GL_TRUE if success, GL_FALSE if unable to do the readpixels
+ */
+static GLboolean
+fast_read_rgba_pixels( struct gl_context *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum format, GLenum type,
+ GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing,
+ GLbitfield transferOps)
+{
+ struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer;
+
+ if (!rb)
+ return GL_FALSE;
+
+ ASSERT(rb->_BaseFormat == GL_RGBA || rb->_BaseFormat == GL_RGB ||
+ rb->_BaseFormat == GL_ALPHA);
+
+ /* clipping should have already been done */
+ ASSERT(x + width <= (GLint) rb->Width);
+ ASSERT(y + height <= (GLint) rb->Height);
+
+ /* check for things we can't handle here */
+ if (transferOps ||
+ packing->SwapBytes ||
+ packing->LsbFirst) {
+ return GL_FALSE;
+ }
+
+ if (format == GL_RGBA && rb->DataType == type) {
+ const GLint dstStride = _mesa_image_row_stride(packing, width,
+ format, type);
+ GLubyte *dest
+ = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height,
+ format, type, 0, 0);
+ GLint row;
+ ASSERT(rb->GetRow);
+ for (row = 0; row < height; row++) {
+ rb->GetRow(ctx, rb, width, x, y + row, dest);
+ dest += dstStride;
+ }
+ return GL_TRUE;
+ }
+
+ if (format == GL_RGB &&
+ rb->DataType == GL_UNSIGNED_BYTE &&
+ type == GL_UNSIGNED_BYTE) {
+ const GLint dstStride = _mesa_image_row_stride(packing, width,
+ format, type);
+ GLubyte *dest
+ = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height,
+ format, type, 0, 0);
+ GLint row;
+ ASSERT(rb->GetRow);
+ for (row = 0; row < height; row++) {
+ GLubyte tempRow[MAX_WIDTH][4];
+ GLint col;
+ rb->GetRow(ctx, rb, width, x, y + row, tempRow);
+ /* convert RGBA to RGB */
+ for (col = 0; col < width; col++) {
+ dest[col * 3 + 0] = tempRow[col][0];
+ dest[col * 3 + 1] = tempRow[col][1];
+ dest[col * 3 + 2] = tempRow[col][2];
+ }
+ dest += dstStride;
+ }
+ return GL_TRUE;
+ }
+
+ /* not handled */
+ return GL_FALSE;
+}
+
+
+/**
+ * When we're using a low-precision color buffer (like 16-bit 5/6/5)
+ * we have to adjust our color values a bit to pass conformance.
+ * The problem is when a 5 or 6-bit color value is converted to an 8-bit
+ * value and then a floating point value, the floating point values don't
+ * increment uniformly as the 5 or 6-bit value is incremented.
+ *
+ * This function adjusts floating point values to compensate.
+ */
+static void
+adjust_colors(const struct gl_framebuffer *fb, GLuint n, GLfloat rgba[][4])
+{
+ const GLuint rShift = 8 - fb->Visual.redBits;
+ const GLuint gShift = 8 - fb->Visual.greenBits;
+ const GLuint bShift = 8 - fb->Visual.blueBits;
+ GLfloat rScale = 1.0F / (GLfloat) ((1 << fb->Visual.redBits ) - 1);
+ GLfloat gScale = 1.0F / (GLfloat) ((1 << fb->Visual.greenBits) - 1);
+ GLfloat bScale = 1.0F / (GLfloat) ((1 << fb->Visual.blueBits ) - 1);
+ GLuint i;
+
+ if (fb->Visual.redBits == 0)
+ rScale = 0;
+ if (fb->Visual.greenBits == 0)
+ gScale = 0;
+ if (fb->Visual.blueBits == 0)
+ bScale = 0;
+
+ for (i = 0; i < n; i++) {
+ GLint r, g, b;
+ /* convert float back to ubyte */
+ CLAMPED_FLOAT_TO_UBYTE(r, rgba[i][RCOMP]);
+ CLAMPED_FLOAT_TO_UBYTE(g, rgba[i][GCOMP]);
+ CLAMPED_FLOAT_TO_UBYTE(b, rgba[i][BCOMP]);
+ /* using only the N most significant bits of the ubyte value, convert to
+ * float in [0,1].
+ */
+ rgba[i][RCOMP] = (GLfloat) (r >> rShift) * rScale;
+ rgba[i][GCOMP] = (GLfloat) (g >> gShift) * gScale;
+ rgba[i][BCOMP] = (GLfloat) (b >> bShift) * bScale;
+ }
+}
+
+
+
+/*
+ * Read R, G, B, A, RGB, L, or LA pixels.
+ */
+static void
+read_rgba_pixels( struct gl_context *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum format, GLenum type, GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing )
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ GLbitfield transferOps = ctx->_ImageTransferState;
+ struct gl_framebuffer *fb = ctx->ReadBuffer;
+ struct gl_renderbuffer *rb = fb->_ColorReadBuffer;
+
+ if (!rb)
+ return;
+
+ if (type == GL_FLOAT && ((ctx->Color.ClampReadColor == GL_TRUE) ||
+ (ctx->Color.ClampReadColor == GL_FIXED_ONLY_ARB &&
+ rb->DataType != GL_FLOAT)))
+ transferOps |= IMAGE_CLAMP_BIT;
+
+ /* Try optimized path first */
+ if (fast_read_rgba_pixels(ctx, x, y, width, height,
+ format, type, pixels, packing, transferOps)) {
+ return; /* done! */
+ }
+
+ /* width should never be > MAX_WIDTH since we did clipping earlier */
+ ASSERT(width <= MAX_WIDTH);
+
+ do {
+ const GLint dstStride
+ = _mesa_image_row_stride(packing, width, format, type);
+ GLfloat (*rgba)[4] = swrast->SpanArrays->attribs[FRAG_ATTRIB_COL0];
+ GLint row;
+ GLubyte *dst
+ = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height,
+ format, type, 0, 0);
+
+ for (row = 0; row < height; row++, y++) {
+
+ /* Get float rgba pixels */
+ _swrast_read_rgba_span(ctx, rb, width, x, y, GL_FLOAT, rgba);
+
+ /* apply fudge factor for shallow color buffers */
+ if (fb->Visual.redBits < 8 ||
+ fb->Visual.greenBits < 8 ||
+ fb->Visual.blueBits < 8) {
+ adjust_colors(fb, width, rgba);
+ }
+
+ /* pack the row of RGBA pixels into user's buffer */
+ _mesa_pack_rgba_span_float(ctx, width, rgba, format, type, dst,
+ packing, transferOps);
+
+ dst += dstStride;
+ }
+ } while (0);
+}
+
+
+/**
+ * Read combined depth/stencil values.
+ * We'll have already done error checking to be sure the expected
+ * depth and stencil buffers really exist.
+ */
+static void
+read_depth_stencil_pixels(struct gl_context *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum type, GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing )
+{
+ const GLboolean scaleOrBias
+ = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0;
+ const GLboolean stencilTransfer = ctx->Pixel.IndexShift
+ || ctx->Pixel.IndexOffset || ctx->Pixel.MapStencilFlag;
+ struct gl_renderbuffer *depthRb, *stencilRb;
+
+ depthRb = ctx->ReadBuffer->_DepthBuffer;
+ stencilRb = ctx->ReadBuffer->_StencilBuffer;
+
+ if (!depthRb || !stencilRb)
+ return;
+
+ depthRb = ctx->ReadBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
+ stencilRb = ctx->ReadBuffer->Attachment[BUFFER_STENCIL].Renderbuffer;
+
+ if (depthRb->_BaseFormat == GL_DEPTH_STENCIL_EXT &&
+ stencilRb->_BaseFormat == GL_DEPTH_STENCIL_EXT &&
+ depthRb == stencilRb &&
+ !scaleOrBias &&
+ !stencilTransfer) {
+ /* This is the ideal case.
+ * Reading GL_DEPTH_STENCIL pixels from combined depth/stencil buffer.
+ * Plus, no pixel transfer ops to worry about!
+ */
+ GLint i;
+ GLint dstStride = _mesa_image_row_stride(packing, width,
+ GL_DEPTH_STENCIL_EXT, type);
+ GLubyte *dst = (GLubyte *) _mesa_image_address2d(packing, pixels,
+ width, height,
+ GL_DEPTH_STENCIL_EXT,
+ type, 0, 0);
+ for (i = 0; i < height; i++) {
+ depthRb->GetRow(ctx, depthRb, width, x, y + i, dst);
+ dst += dstStride;
+ }
+ }
+ else {
+ /* Reading GL_DEPTH_STENCIL pixels from separate depth/stencil buffers,
+ * or we need pixel transfer.
+ */
+ GLint i;
+ depthRb = ctx->ReadBuffer->_DepthBuffer;
+ stencilRb = ctx->ReadBuffer->_StencilBuffer;
+
+ for (i = 0; i < height; i++) {
+ GLstencil stencilVals[MAX_WIDTH];
+
+ GLuint *depthStencilDst = (GLuint *)
+ _mesa_image_address2d(packing, pixels, width, height,
+ GL_DEPTH_STENCIL_EXT, type, i, 0);
+
+ _swrast_read_stencil_span(ctx, stencilRb, width,
+ x, y + i, stencilVals);
+
+ if (!scaleOrBias && !stencilTransfer
+ && ctx->ReadBuffer->Visual.depthBits == 24) {
+ /* ideal case */
+ GLuint zVals[MAX_WIDTH]; /* 24-bit values! */
+ GLint j;
+ ASSERT(depthRb->DataType == GL_UNSIGNED_INT);
+ /* note, we've already been clipped */
+ depthRb->GetRow(ctx, depthRb, width, x, y + i, zVals);
+ for (j = 0; j < width; j++) {
+ depthStencilDst[j] = (zVals[j] << 8) | (stencilVals[j] & 0xff);
+ }
+ }
+ else {
+ /* general case */
+ GLfloat depthVals[MAX_WIDTH];
+ _swrast_read_depth_span_float(ctx, depthRb, width, x, y + i,
+ depthVals);
+ _mesa_pack_depth_stencil_span(ctx, width, depthStencilDst,
+ depthVals, stencilVals, packing);
+ }
+ }
+ }
+}
+
+
+
+/**
+ * Software fallback routine for ctx->Driver.ReadPixels().
+ * By time we get here, all error checking will have been done.
+ */
+void
+_swrast_ReadPixels( struct gl_context *ctx,
+ GLint x, GLint y, GLsizei width, GLsizei height,
+ GLenum format, GLenum type,
+ const struct gl_pixelstore_attrib *packing,
+ GLvoid *pixels )
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ struct gl_pixelstore_attrib clippedPacking = *packing;
+
+ if (ctx->NewState)
+ _mesa_update_state(ctx);
+
+ /* Need to do swrast_render_start() before clipping or anything else
+ * since this is where a driver may grab the hw lock and get an updated
+ * window size.
+ */
+ swrast_render_start(ctx);
+
+ if (swrast->NewState)
+ _swrast_validate_derived( ctx );
+
+ /* Do all needed clipping here, so that we can forget about it later */
+ if (_mesa_clip_readpixels(ctx, &x, &y, &width, &height, &clippedPacking)) {
+
+ pixels = _mesa_map_pbo_dest(ctx, &clippedPacking, pixels);
+
+ if (pixels) {
+ switch (format) {
+ case GL_STENCIL_INDEX:
+ read_stencil_pixels(ctx, x, y, width, height, type, pixels,
+ &clippedPacking);
+ break;
+ case GL_DEPTH_COMPONENT:
+ read_depth_pixels(ctx, x, y, width, height, type, pixels,
+ &clippedPacking);
+ break;
+ case GL_DEPTH_STENCIL_EXT:
+ read_depth_stencil_pixels(ctx, x, y, width, height, type, pixels,
+ &clippedPacking);
+ break;
+ default:
+ /* all other formats should be color formats */
+ read_rgba_pixels(ctx, x, y, width, height, format, type, pixels,
+ &clippedPacking);
+ }
+
+ _mesa_unmap_pbo_dest(ctx, &clippedPacking);
+ }
+ }
+
+ swrast_render_finish(ctx);
+}
|