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/* $Id: s_readpix.c,v 1.1 2003-02-28 11:49:42 pj Exp $ */
/*
* Mesa 3-D graphics library
* Version: 4.1
*
* Copyright (C) 1999-2002 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 "imports.h"
#include "pixel.h"
#include "s_alphabuf.h"
#include "s_context.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 )
{
SWcontext *swrast = SWRAST_CONTEXT(ctx);
GLint i, readWidth;
/* error checking */
if (ctx->Visual.rgbMode) {
_mesa_error( ctx, GL_INVALID_OPERATION, "glReadPixels" );
return;
}
_swrast_use_read_buffer(ctx);
readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
/* process image row by row */
for (i = 0; i < height; i++) {
GLuint index[MAX_WIDTH];
GLvoid *dest;
(*swrast->Driver.ReadCI32Span)(ctx, readWidth, x, y + i, index);
dest = _mesa_image_address(packing, pixels, width, height,
GL_COLOR_INDEX, type, 0, i, 0);
_mesa_pack_index_span(ctx, readWidth, type, dest, index,
&ctx->Pack, ctx->_ImageTransferState);
}
_swrast_use_draw_buffer(ctx);
}
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 readWidth;
GLboolean bias_or_scale;
/* Error checking */
if (ctx->Visual.depthBits <= 0) {
/* No depth buffer */
_mesa_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) {
_mesa_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. */
GLint j;
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. */
GLint j;
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) */
GLint j;
for (j=0;j<height;j++,y++) {
GLfloat depth[MAX_WIDTH];
GLvoid *dest;
_mesa_read_depth_span_float(ctx, readWidth, x, y, depth);
dest = _mesa_image_address(packing, pixels, width, height,
GL_DEPTH_COMPONENT, type, 0, j, 0);
_mesa_pack_depth_span(ctx, readWidth, (GLdepth *) dest, type,
depth, &ctx->Pack);
}
}
}
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 )
{
GLint 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) {
_mesa_error( ctx, GL_INVALID_OPERATION, "glReadPixels(stencil type)");
return;
}
readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
if (ctx->Visual.stencilBits <= 0) {
/* No stencil buffer */
_mesa_error( ctx, GL_INVALID_OPERATION, "glReadPixels" );
return;
}
/* 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);
dest = _mesa_image_address(packing, pixels, width, height,
GL_STENCIL_INDEX, type, 0, j, 0);
_mesa_pack_stencil_span(ctx, readWidth, type, dest, stencil, &ctx->Pack);
}
}
/*
* 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 )
{
SWcontext *swrast = SWRAST_CONTEXT(ctx);
/* 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 < 0) {
skipPixels -= srcX;
readWidth += srcX;
srcX = 0;
}
if (srcX + readWidth > (GLint) ctx->ReadBuffer->Width)
readWidth -= (srcX + readWidth - (GLint) ctx->ReadBuffer->Width);
if (readWidth <= 0)
return GL_TRUE;
/* vertical clipping */
if (srcY < 0) {
skipRows -= srcY;
readHeight += srcY;
srcY = 0;
}
if (srcY + readHeight > (GLint) ctx->ReadBuffer->Height)
readHeight -= (srcY + readHeight - (GLint) ctx->ReadBuffer->Height);
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;
if (packing->Invert) {
/* start at top and go down */
dest += (readHeight - 1) * rowLength * 4;
rowLength = -rowLength;
}
for (row=0; row<readHeight; row++) {
(*swrast->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 )
{
SWcontext *swrast = SWRAST_CONTEXT(ctx);
GLint readWidth;
_swrast_use_read_buffer(ctx);
/* Try optimized path first */
if (read_fast_rgba_pixels( ctx, x, y, width, height,
format, type, pixels, packing )) {
_swrast_use_draw_buffer(ctx);
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:
_mesa_error( ctx, GL_INVALID_ENUM, "glReadPixels(type)" );
return;
}
if (!_mesa_is_legal_format_and_type(format, type) ||
format == GL_INTENSITY) {
_mesa_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) {
_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++) {
GLchan rgba[MAX_WIDTH][4];
if (ctx->Visual.rgbMode) {
_mesa_read_rgba_span(ctx, ctx->ReadBuffer, readWidth, x, y, rgba);
}
else {
GLuint index[MAX_WIDTH];
(*swrast->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, readWidth, 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.rgbMode) {
_mesa_read_rgba_span(ctx, ctx->ReadBuffer, readWidth, x, y, rgba);
}
else {
GLuint index[MAX_WIDTH];
(*swrast->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);
if (ctx->Visual.redBits < CHAN_BITS ||
ctx->Visual.greenBits < CHAN_BITS ||
ctx->Visual.blueBits < CHAN_BITS) {
/* Requantize the color values into floating point and go from
* there. This fixes conformance failures with 16-bit color
* buffers, for example.
*/
DEFMARRAY(GLfloat, rgbaf, MAX_WIDTH, 4); /* mac 32k limitation */
CHECKARRAY(rgbaf, return); /* mac 32k limitation */
_mesa_chan_to_float_span(ctx, readWidth,
(CONST GLchan (*)[4]) rgba, rgbaf);
_mesa_pack_float_rgba_span(ctx, readWidth,
(CONST GLfloat (*)[4]) rgbaf,
format, type, dst, packing,
ctx->_ImageTransferState);
UNDEFARRAY(rgbaf); /* mac 32k limitation */
}
else {
/* GLubytes are fine */
_mesa_pack_rgba_span(ctx, readWidth, (CONST GLchan (*)[4]) rgba,
format, type, dst, packing,
ctx->_ImageTransferState);
}
}
}
_swrast_use_draw_buffer(ctx);
}
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 )
{
SWcontext *swrast = SWRAST_CONTEXT(ctx);
(void) pack;
if (swrast->NewState)
_swrast_validate_derived( ctx );
RENDER_START(swrast,ctx);
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:
_mesa_error( ctx, GL_INVALID_ENUM, "glReadPixels(format)" );
}
RENDER_FINISH(swrast,ctx);
}