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Diffstat (limited to 'mesalib/src/mesa/swrast/s_readpix.c')
-rw-r--r--mesalib/src/mesa/swrast/s_readpix.c1086
1 files changed, 508 insertions, 578 deletions
diff --git a/mesalib/src/mesa/swrast/s_readpix.c b/mesalib/src/mesa/swrast/s_readpix.c
index 1de481248..61399010b 100644
--- a/mesalib/src/mesa/swrast/s_readpix.c
+++ b/mesalib/src/mesa/swrast/s_readpix.c
@@ -1,578 +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/bufferobj.h"
-#include "main/colormac.h"
-#include "main/convolve.h"
-#include "main/feedback.h"
-#include "main/formats.h"
-#include "main/image.h"
-#include "main/macros.h"
-#include "main/imports.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( GLcontext *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( GLcontext *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( GLcontext *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( GLcontext *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);
-
- if (ctx->Pixel.Convolution2DEnabled || ctx->Pixel.Separable2DEnabled) {
- GLfloat *dest, *src, *tmpImage, *convImage;
- GLint row;
-
- tmpImage = (GLfloat *) malloc(width * height * 4 * sizeof(GLfloat));
- if (!tmpImage) {
- _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
- return;
- }
- convImage = (GLfloat *) malloc(width * height * 4 * sizeof(GLfloat));
- if (!convImage) {
- free(tmpImage);
- _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
- return;
- }
-
- /* read full RGBA, FLOAT image */
- dest = tmpImage;
- for (row = 0; row < height; row++, y++) {
- _swrast_read_rgba_span(ctx, rb, width, x, y, GL_FLOAT, dest);
- _mesa_apply_rgba_transfer_ops(ctx,
- transferOps & IMAGE_PRE_CONVOLUTION_BITS,
- width, (GLfloat (*)[4]) dest);
- dest += width * 4;
- }
-
- /* do convolution */
- if (ctx->Pixel.Convolution2DEnabled) {
- _mesa_convolve_2d_image(ctx, &width, &height, tmpImage, convImage);
- }
- else {
- ASSERT(ctx->Pixel.Separable2DEnabled);
- _mesa_convolve_sep_image(ctx, &width, &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_address2d(packing, pixels, width, height,
- format, type, row, 0);
- _mesa_pack_rgba_span_float(ctx, width, (GLfloat (*)[4]) src,
- format, type, dest, packing,
- transferOps & IMAGE_POST_CONVOLUTION_BITS);
- src += width * 4;
- }
- free(convImage);
- }
- else {
- /* no convolution */
- 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);
-
- /* make sure we don't apply 1D convolution */
- transferOps &= ~(IMAGE_CONVOLUTION_BIT |
- IMAGE_POST_CONVOLUTION_SCALE_BIAS);
-
- 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;
- }
- }
-}
-
-
-/**
- * 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(GLcontext *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( GLcontext *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)) {
- /* The ReadPixels region is totally outside the window bounds */
- swrast_render_finish(ctx);
- return;
- }
-
- pixels = _mesa_map_pbo_dest(ctx, &clippedPacking, pixels);
- if (!pixels)
- return;
-
- 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_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, &clippedPacking);
- break;
- case GL_DEPTH_STENCIL_EXT:
- read_depth_stencil_pixels(ctx, x, y, width, height,
- type, pixels, &clippedPacking);
- break;
- default:
- _mesa_problem(ctx, "unexpected format in _swrast_ReadPixels");
- /* don't return yet, clean-up */
- }
-
- swrast_render_finish(ctx);
-
- _mesa_unmap_pbo_dest(ctx, &clippedPacking);
-}
+/*
+ * 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/bufferobj.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/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);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 10:00:58 +0000