diff options
Diffstat (limited to 'mesalib/src/mesa/swrast/s_readpix.c')
| -rw-r--r-- | mesalib/src/mesa/swrast/s_readpix.c | 1028 |
1 files changed, 514 insertions, 514 deletions
diff --git a/mesalib/src/mesa/swrast/s_readpix.c b/mesalib/src/mesa/swrast/s_readpix.c index 49da247e9..6eec2fc78 100644 --- a/mesalib/src/mesa/swrast/s_readpix.c +++ b/mesalib/src/mesa/swrast/s_readpix.c @@ -1,514 +1,514 @@ -/*
- * 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_RG ||
- rb->_BaseFormat == GL_RED ||
- rb->_BaseFormat == GL_LUMINANCE ||
- rb->_BaseFormat == GL_INTENSITY ||
- rb->_BaseFormat == GL_LUMINANCE_ALPHA ||
- 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 ((ctx->Color._ClampReadColor == GL_TRUE || type != GL_FLOAT) &&
- !_mesa_is_integer_format(format)) {
- transferOps |= IMAGE_CLAMP_BIT;
- }
-
- /* Try the 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);
-
- {
- 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.redBits != 0) ||
- (fb->Visual.greenBits < 8 && fb->Visual.greenBits != 0) ||
- (fb->Visual.blueBits < 8 && fb->Visual.blueBits != 0)) {
- 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(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, type, 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_RG || + rb->_BaseFormat == GL_RED || + rb->_BaseFormat == GL_LUMINANCE || + rb->_BaseFormat == GL_INTENSITY || + rb->_BaseFormat == GL_LUMINANCE_ALPHA || + 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 ((ctx->Color._ClampReadColor == GL_TRUE || type != GL_FLOAT) && + !_mesa_is_integer_format(format)) { + transferOps |= IMAGE_CLAMP_BIT; + } + + /* Try the 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); + + { + 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.redBits != 0) || + (fb->Visual.greenBits < 8 && fb->Visual.greenBits != 0) || + (fb->Visual.blueBits < 8 && fb->Visual.blueBits != 0)) { + 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(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, type, 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); +} |