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path: root/src/mesa/swrast/s_readpix.c
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Diffstat (limited to 'src/mesa/swrast/s_readpix.c')
-rw-r--r--src/mesa/swrast/s_readpix.c765
1 files changed, 765 insertions, 0 deletions
diff --git a/src/mesa/swrast/s_readpix.c b/src/mesa/swrast/s_readpix.c
new file mode 100644
index 0000000000..74a4d68266
--- /dev/null
+++ b/src/mesa/swrast/s_readpix.c
@@ -0,0 +1,765 @@
+/* $Id: s_readpix.c,v 1.1 2000/10/31 18:00:04 keithw Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 3.5
+ *
+ * Copyright (C) 1999-2000 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 "glheader.h"
+#include "colormac.h"
+#include "convolve.h"
+#include "context.h"
+#include "feedback.h"
+#include "image.h"
+#include "macros.h"
+#include "mem.h"
+#include "pixel.h"
+
+#include "s_alphabuf.h"
+#include "s_depth.h"
+#include "s_span.h"
+#include "s_stencil.h"
+
+
+
+/*
+ * Read a block of color index pixels.
+ */
+static void read_index_pixels( GLcontext *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum type, GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing )
+{
+ GLint i, j, readWidth;
+
+ /* error checking */
+ if (ctx->Visual.RGBAflag) {
+ gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels" );
+ return;
+ }
+
+ ASSERT(ctx->Driver.SetReadBuffer);
+ (*ctx->Driver.SetReadBuffer)(ctx, ctx->ReadBuffer, ctx->Pixel.DriverReadBuffer);
+
+ readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
+
+ /* process image row by row */
+ for (j=0;j<height;j++,y++) {
+ GLuint index[MAX_WIDTH];
+ GLvoid *dest;
+
+ (*ctx->Driver.ReadCI32Span)( ctx, readWidth, x, y, index );
+
+ if (ctx->Pixel.IndexShift!=0 || ctx->Pixel.IndexOffset!=0) {
+ _mesa_shift_and_offset_ci( ctx, readWidth, index);
+ }
+
+ if (ctx->Pixel.MapColorFlag) {
+ _mesa_map_ci(ctx, readWidth, index);
+ }
+
+ dest = _mesa_image_address(packing, pixels,
+ width, height, GL_COLOR_INDEX, type, 0, j, 0);
+
+ switch (type) {
+ case GL_UNSIGNED_BYTE:
+ {
+ GLubyte *dst = (GLubyte *) dest;
+ for (i=0;i<readWidth;i++) {
+ *dst++ = (GLubyte) index[i];
+ }
+ }
+ break;
+ case GL_BYTE:
+ {
+ GLbyte *dst = (GLbyte *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLbyte) index[i];
+ }
+ }
+ break;
+ case GL_UNSIGNED_SHORT:
+ {
+ GLushort *dst = (GLushort *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLushort) index[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap2( (GLushort *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_SHORT:
+ {
+ GLshort *dst = (GLshort *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLshort) index[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap2( (GLushort *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_UNSIGNED_INT:
+ {
+ GLuint *dst = (GLuint *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLuint) index[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap4( (GLuint *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_INT:
+ {
+ GLint *dst = (GLint *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLint) index[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap4( (GLuint *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_FLOAT:
+ {
+ GLfloat *dst = (GLfloat *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLfloat) index[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap4( (GLuint *) dst, readWidth );
+ }
+ }
+ break;
+ default:
+ gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(type)" );
+ j = height + 1; /* exit loop */
+ }
+ }
+
+ (*ctx->Driver.SetReadBuffer)(ctx, ctx->DrawBuffer, ctx->Color.DriverDrawBuffer);
+}
+
+
+
+static void read_depth_pixels( GLcontext *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum type, GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing )
+{
+ GLint i, j, readWidth;
+ GLboolean bias_or_scale;
+
+ /* Error checking */
+ if (ctx->Visual.DepthBits <= 0) {
+ /* No depth buffer */
+ gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels" );
+ return;
+ }
+
+ readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
+
+ if (type != GL_BYTE &&
+ type != GL_UNSIGNED_BYTE &&
+ type != GL_SHORT &&
+ type != GL_UNSIGNED_SHORT &&
+ type != GL_INT &&
+ type != GL_UNSIGNED_INT &&
+ type != GL_FLOAT) {
+ gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels(depth type)");
+ return;
+ }
+
+ bias_or_scale = ctx->Pixel.DepthBias!=0.0 || ctx->Pixel.DepthScale!=1.0;
+
+ if (type==GL_UNSIGNED_SHORT && ctx->Visual.DepthBits == 16
+ && !bias_or_scale && !packing->SwapBytes) {
+ /* Special case: directly read 16-bit unsigned depth values. */
+ for (j=0;j<height;j++,y++) {
+ GLdepth depth[MAX_WIDTH];
+ GLushort *dst = (GLushort*) _mesa_image_address( packing, pixels,
+ width, height, GL_DEPTH_COMPONENT, type, 0, j, 0 );
+ GLint i;
+ _mesa_read_depth_span(ctx, width, x, y, depth);
+ for (i = 0; i < width; i++)
+ dst[i] = depth[i];
+ }
+ }
+ else if (type==GL_UNSIGNED_INT && ctx->Visual.DepthBits == 32
+ && !bias_or_scale && !packing->SwapBytes) {
+ /* Special case: directly read 32-bit unsigned depth values. */
+ for (j=0;j<height;j++,y++) {
+ GLdepth *dst = (GLdepth *) _mesa_image_address( packing, pixels,
+ width, height, GL_DEPTH_COMPONENT, type, 0, j, 0 );
+ _mesa_read_depth_span(ctx, width, x, y, dst);
+ }
+ }
+ else {
+ /* General case (slower) */
+ for (j=0;j<height;j++,y++) {
+ GLfloat depth[MAX_WIDTH];
+ GLvoid *dest;
+
+ _mesa_read_depth_span_float(ctx, readWidth, x, y, depth);
+
+ if (bias_or_scale) {
+ for (i=0;i<readWidth;i++) {
+ GLfloat d;
+ d = depth[i] * ctx->Pixel.DepthScale + ctx->Pixel.DepthBias;
+ depth[i] = CLAMP( d, 0.0F, 1.0F );
+ }
+ }
+
+ dest = _mesa_image_address(packing, pixels,
+ width, height, GL_DEPTH_COMPONENT, type, 0, j, 0);
+
+ switch (type) {
+ case GL_UNSIGNED_BYTE:
+ {
+ GLubyte *dst = (GLubyte *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = FLOAT_TO_UBYTE( depth[i] );
+ }
+ }
+ break;
+ case GL_BYTE:
+ {
+ GLbyte *dst = (GLbyte *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = FLOAT_TO_BYTE( depth[i] );
+ }
+ }
+ break;
+ case GL_UNSIGNED_SHORT:
+ {
+ GLushort *dst = (GLushort *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = FLOAT_TO_USHORT( depth[i] );
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap2( (GLushort *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_SHORT:
+ {
+ GLshort *dst = (GLshort *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = FLOAT_TO_SHORT( depth[i] );
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap2( (GLushort *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_UNSIGNED_INT:
+ {
+ GLuint *dst = (GLuint *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = FLOAT_TO_UINT( depth[i] );
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap4( (GLuint *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_INT:
+ {
+ GLint *dst = (GLint *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = FLOAT_TO_INT( depth[i] );
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap4( (GLuint *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_FLOAT:
+ {
+ GLfloat *dst = (GLfloat *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = depth[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap4( (GLuint *) dst, readWidth );
+ }
+ }
+ break;
+ default:
+ gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(type)" );
+ }
+ }
+ }
+}
+
+
+
+static void read_stencil_pixels( GLcontext *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum type, GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing )
+{
+ GLboolean shift_or_offset;
+ GLint i, j, readWidth;
+
+ if (type != GL_BYTE &&
+ type != GL_UNSIGNED_BYTE &&
+ type != GL_SHORT &&
+ type != GL_UNSIGNED_SHORT &&
+ type != GL_INT &&
+ type != GL_UNSIGNED_INT &&
+ type != GL_FLOAT &&
+ type != GL_BITMAP) {
+ gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels(stencil type)");
+ return;
+ }
+
+ readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
+
+ if (ctx->Visual.StencilBits<=0) {
+ /* No stencil buffer */
+ gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels" );
+ return;
+ }
+
+ shift_or_offset = ctx->Pixel.IndexShift!=0 || ctx->Pixel.IndexOffset!=0;
+
+ /* process image row by row */
+ for (j=0;j<height;j++,y++) {
+ GLvoid *dest;
+ GLstencil stencil[MAX_WIDTH];
+
+ _mesa_read_stencil_span( ctx, readWidth, x, y, stencil );
+
+ if (shift_or_offset) {
+ _mesa_shift_and_offset_stencil( ctx, readWidth, stencil );
+ }
+
+ if (ctx->Pixel.MapStencilFlag) {
+ _mesa_map_stencil( ctx, readWidth, stencil );
+ }
+
+ dest = _mesa_image_address( packing, pixels,
+ width, height, GL_STENCIL_INDEX, type, 0, j, 0 );
+
+ switch (type) {
+ case GL_UNSIGNED_BYTE:
+ if (sizeof(GLstencil) == 8) {
+ MEMCPY( dest, stencil, readWidth );
+ }
+ else {
+ GLubyte *dst = (GLubyte *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLubyte) stencil[i];
+ }
+ }
+ break;
+ case GL_BYTE:
+ if (sizeof(GLstencil) == 8) {
+ MEMCPY( dest, stencil, readWidth );
+ }
+ else {
+ GLbyte *dst = (GLbyte *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLbyte) stencil[i];
+ }
+ }
+ break;
+ case GL_UNSIGNED_SHORT:
+ {
+ GLushort *dst = (GLushort *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLushort) stencil[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap2( (GLushort *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_SHORT:
+ {
+ GLshort *dst = (GLshort *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLshort) stencil[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap2( (GLushort *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_UNSIGNED_INT:
+ {
+ GLuint *dst = (GLuint *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLuint) stencil[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap4( (GLuint *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_INT:
+ {
+ GLint *dst = (GLint *) dest;
+ for (i=0;i<readWidth;i++) {
+ *dst++ = (GLint) stencil[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap4( (GLuint *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_FLOAT:
+ {
+ GLfloat *dst = (GLfloat *) dest;
+ for (i=0;i<readWidth;i++) {
+ dst[i] = (GLfloat) stencil[i];
+ }
+ if (packing->SwapBytes) {
+ _mesa_swap4( (GLuint *) dst, readWidth );
+ }
+ }
+ break;
+ case GL_BITMAP:
+ if (packing->LsbFirst) {
+ GLubyte *dst = (GLubyte*) dest;
+ GLint shift = 0;
+ for (i = 0; i < readWidth; i++) {
+ if (shift == 0)
+ *dst = 0;
+ *dst |= ((stencil != 0) << shift);
+ shift++;
+ if (shift == 8) {
+ shift = 0;
+ dst++;
+ }
+ }
+ }
+ else {
+ GLubyte *dst = (GLubyte*) dest;
+ GLint shift = 7;
+ for (i = 0; i < readWidth; i++) {
+ if (shift == 7)
+ *dst = 0;
+ *dst |= ((stencil != 0) << shift);
+ shift--;
+ if (shift < 0) {
+ shift = 7;
+ dst++;
+ }
+ }
+ }
+ break;
+ default:
+ gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(type)" );
+ }
+ }
+}
+
+
+
+/*
+ * Optimized glReadPixels for particular pixel formats:
+ * GL_UNSIGNED_BYTE, GL_RGBA
+ * when pixel scaling, biasing and mapping are disabled.
+ */
+static GLboolean
+read_fast_rgba_pixels( GLcontext *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum format, GLenum type,
+ GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing )
+{
+ /* can't do scale, bias, mapping, etc */
+ if (ctx->ImageTransferState)
+ return GL_FALSE;
+
+ /* can't do fancy pixel packing */
+ if (packing->Alignment != 1 || packing->SwapBytes || packing->LsbFirst)
+ return GL_FALSE;
+
+ {
+ GLint srcX = x;
+ GLint srcY = y;
+ GLint readWidth = width; /* actual width read */
+ GLint readHeight = height; /* actual height read */
+ GLint skipPixels = packing->SkipPixels;
+ GLint skipRows = packing->SkipRows;
+ GLint rowLength;
+
+ if (packing->RowLength > 0)
+ rowLength = packing->RowLength;
+ else
+ rowLength = width;
+
+ /* horizontal clipping */
+ if (srcX < ctx->ReadBuffer->Xmin) {
+ skipPixels += (ctx->ReadBuffer->Xmin - srcX);
+ readWidth -= (ctx->ReadBuffer->Xmin - srcX);
+ srcX = ctx->ReadBuffer->Xmin;
+ }
+ if (srcX + readWidth > ctx->ReadBuffer->Xmax)
+ readWidth -= (srcX + readWidth - ctx->ReadBuffer->Xmax);
+ if (readWidth <= 0)
+ return GL_TRUE;
+
+ /* vertical clipping */
+ if (srcY < ctx->ReadBuffer->Ymin) {
+ skipRows += (ctx->ReadBuffer->Ymin - srcY);
+ readHeight -= (ctx->ReadBuffer->Ymin - srcY);
+ srcY = ctx->ReadBuffer->Ymin;
+ }
+ if (srcY + readHeight > ctx->ReadBuffer->Ymax)
+ readHeight -= (srcY + readHeight - ctx->ReadBuffer->Ymax);
+ if (readHeight <= 0)
+ return GL_TRUE;
+
+ /*
+ * Ready to read!
+ * The window region at (destX, destY) of size (readWidth, readHeight)
+ * will be read back.
+ * We'll write pixel data to buffer pointed to by "pixels" but we'll
+ * skip "skipRows" rows and skip "skipPixels" pixels/row.
+ */
+#if CHAN_BITS == 8
+ if (format == GL_RGBA && type == GL_UNSIGNED_BYTE) {
+#elif CHAN_BITS == 16
+ if (format == GL_RGBA && type == GL_UNSIGNED_SHORT) {
+#else
+ if (0) {
+#endif
+ GLchan *dest = (GLchan *) pixels
+ + (skipRows * rowLength + skipPixels) * 4;
+ GLint row;
+ for (row=0; row<readHeight; row++) {
+ (*ctx->Driver.ReadRGBASpan)(ctx, readWidth, srcX, srcY,
+ (GLchan (*)[4]) dest);
+ if (ctx->DrawBuffer->UseSoftwareAlphaBuffers) {
+ _mesa_read_alpha_span(ctx, readWidth, srcX, srcY,
+ (GLchan (*)[4]) dest);
+ }
+ dest += rowLength * 4;
+ srcY++;
+ }
+ return GL_TRUE;
+ }
+ else {
+ /* can't do this format/type combination */
+ return GL_FALSE;
+ }
+ }
+}
+
+
+
+/*
+ * Read R, G, B, A, RGB, L, or LA pixels.
+ */
+static void read_rgba_pixels( GLcontext *ctx,
+ GLint x, GLint y,
+ GLsizei width, GLsizei height,
+ GLenum format, GLenum type, GLvoid *pixels,
+ const struct gl_pixelstore_attrib *packing )
+{
+ GLint readWidth;
+
+ (*ctx->Driver.SetReadBuffer)(ctx, ctx->ReadBuffer, ctx->Pixel.DriverReadBuffer);
+
+ /* Try optimized path first */
+ if (read_fast_rgba_pixels( ctx, x, y, width, height,
+ format, type, pixels, packing )) {
+
+ (*ctx->Driver.SetReadBuffer)(ctx, ctx->DrawBuffer, ctx->Color.DriverDrawBuffer);
+ return; /* done! */
+ }
+
+ readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
+
+ /* do error checking on pixel type, format was already checked by caller */
+ switch (type) {
+ case GL_UNSIGNED_BYTE:
+ case GL_BYTE:
+ case GL_UNSIGNED_SHORT:
+ case GL_SHORT:
+ case GL_UNSIGNED_INT:
+ case GL_INT:
+ case GL_FLOAT:
+ case GL_UNSIGNED_BYTE_3_3_2:
+ case GL_UNSIGNED_BYTE_2_3_3_REV:
+ case GL_UNSIGNED_SHORT_5_6_5:
+ case GL_UNSIGNED_SHORT_5_6_5_REV:
+ case GL_UNSIGNED_SHORT_4_4_4_4:
+ case GL_UNSIGNED_SHORT_4_4_4_4_REV:
+ case GL_UNSIGNED_SHORT_5_5_5_1:
+ case GL_UNSIGNED_SHORT_1_5_5_5_REV:
+ case GL_UNSIGNED_INT_8_8_8_8:
+ case GL_UNSIGNED_INT_8_8_8_8_REV:
+ case GL_UNSIGNED_INT_10_10_10_2:
+ case GL_UNSIGNED_INT_2_10_10_10_REV:
+ /* valid pixel type */
+ break;
+ default:
+ gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(type)" );
+ return;
+ }
+
+ if (!_mesa_is_legal_format_and_type(format, type) ||
+ format == GL_INTENSITY) {
+ gl_error(ctx, GL_INVALID_OPERATION, "glReadPixels(format or type)");
+ return;
+ }
+
+ if (ctx->Pixel.Convolution2DEnabled || ctx->Pixel.Separable2DEnabled) {
+ const GLuint transferOps = ctx->ImageTransferState;
+ GLfloat *dest, *src, *tmpImage, *convImage;
+ GLint row;
+
+ tmpImage = (GLfloat *) MALLOC(width * height * 4 * sizeof(GLfloat));
+ if (!tmpImage) {
+ gl_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
+ return;
+ }
+ convImage = (GLfloat *) MALLOC(width * height * 4 * sizeof(GLfloat));
+ if (!convImage) {
+ FREE(tmpImage);
+ gl_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
+ return;
+ }
+
+ /* read full RGBA, FLOAT image */
+ dest = tmpImage;
+ for (row = 0; row < height; row++, y++) {
+ GLchan rgba[MAX_WIDTH][4];
+ if (ctx->Visual.RGBAflag) {
+ gl_read_rgba_span(ctx, ctx->ReadBuffer, readWidth, x, y, rgba);
+ }
+ else {
+ GLuint index[MAX_WIDTH];
+ (*ctx->Driver.ReadCI32Span)(ctx, readWidth, x, y, index);
+ if (ctx->Pixel.IndexShift != 0 || ctx->Pixel.IndexOffset !=0 ) {
+ _mesa_map_ci(ctx, readWidth, index);
+ }
+ _mesa_map_ci_to_rgba_chan(ctx, readWidth, index, rgba);
+ }
+ _mesa_pack_rgba_span(ctx, readWidth, (const GLchan (*)[4]) rgba,
+ GL_RGBA, GL_FLOAT, dest, &_mesa_native_packing,
+ transferOps & IMAGE_PRE_CONVOLUTION_BITS);
+ dest += width * 4;
+ }
+
+ /* do convolution */
+ if (ctx->Pixel.Convolution2DEnabled) {
+ _mesa_convolve_2d_image(ctx, &readWidth, &height, tmpImage, convImage);
+ }
+ else {
+ ASSERT(ctx->Pixel.Separable2DEnabled);
+ _mesa_convolve_sep_image(ctx, &readWidth, &height, tmpImage, convImage);
+ }
+ FREE(tmpImage);
+
+ /* finish transfer ops and pack the resulting image */
+ src = convImage;
+ for (row = 0; row < height; row++) {
+ GLvoid *dest;
+ dest = _mesa_image_address(packing, pixels, width, height,
+ format, type, 0, row, 0);
+ _mesa_pack_float_rgba_span(ctx, readWidth,
+ (const GLfloat (*)[4]) src,
+ format, type, dest, packing,
+ transferOps & IMAGE_POST_CONVOLUTION_BITS);
+ src += readWidth * 4;
+ }
+ }
+ else {
+ /* no convolution */
+ GLint row;
+ for (row = 0; row < height; row++, y++) {
+ GLchan rgba[MAX_WIDTH][4];
+ GLvoid *dst;
+ if (ctx->Visual.RGBAflag) {
+ gl_read_rgba_span(ctx, ctx->ReadBuffer, readWidth, x, y, rgba);
+ }
+ else {
+ GLuint index[MAX_WIDTH];
+ (*ctx->Driver.ReadCI32Span)(ctx, readWidth, x, y, index);
+ if (ctx->Pixel.IndexShift != 0 || ctx->Pixel.IndexOffset != 0) {
+ _mesa_map_ci(ctx, readWidth, index);
+ }
+ _mesa_map_ci_to_rgba_chan(ctx, readWidth, index, rgba);
+ }
+ dst = _mesa_image_address(packing, pixels, width, height,
+ format, type, 0, row, 0);
+ _mesa_pack_rgba_span(ctx, readWidth, (const GLchan (*)[4]) rgba,
+ format, type, dst, packing,
+ ctx->ImageTransferState);
+ }
+ }
+
+ (*ctx->Driver.SetReadBuffer)(ctx, ctx->DrawBuffer, ctx->Color.DriverDrawBuffer);
+}
+
+
+
+void
+_swrast_ReadPixels( GLcontext *ctx,
+ GLint x, GLint y, GLsizei width, GLsizei height,
+ GLenum format, GLenum type,
+ const struct gl_pixelstore_attrib *pack,
+ GLvoid *pixels )
+{
+ (void) pack;
+
+ switch (format) {
+ case GL_COLOR_INDEX:
+ read_index_pixels(ctx, x, y, width, height, type, pixels, &ctx->Pack);
+ break;
+ case GL_STENCIL_INDEX:
+ read_stencil_pixels(ctx, x,y, width,height, type, pixels, &ctx->Pack);
+ break;
+ case GL_DEPTH_COMPONENT:
+ read_depth_pixels(ctx, x, y, width, height, type, pixels, &ctx->Pack);
+ break;
+ case GL_RED:
+ case GL_GREEN:
+ case GL_BLUE:
+ case GL_ALPHA:
+ case GL_RGB:
+ case GL_LUMINANCE:
+ case GL_LUMINANCE_ALPHA:
+ case GL_RGBA:
+ case GL_BGR:
+ case GL_BGRA:
+ case GL_ABGR_EXT:
+ read_rgba_pixels(ctx, x, y, width, height,
+ format, type, pixels, &ctx->Pack);
+ break;
+ default:
+ gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(format)" );
+ }
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-09 11:53:18 +0000