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authorBrian Paul <[email protected]>2011-11-14 13:06:29 -0700
committerBrian Paul <[email protected]>2011-11-15 07:49:26 -0700
commit94780b5ee6dc118e22c29b5543c4db8e0ab1f393 (patch)
tree703d18507f4275b122e8102c6111886e36b7df5e
parent3754ebb33dc6bfb3db59f23f0b3690134a71aa15 (diff)
st/mesa: remove most of the ReadPixels code
We can use the core Mesa code for glReadPixels now. We just have to validate state and flush the bitmap cache before reading.
-rw-r--r--src/mesa/state_tracker/st_cb_readpixels.c633
-rw-r--r--src/mesa/state_tracker/st_cb_readpixels.h9
2 files changed, 8 insertions, 634 deletions
diff --git a/src/mesa/state_tracker/st_cb_readpixels.c b/src/mesa/state_tracker/st_cb_readpixels.c
index f11d6dbe740..6b824b1615e 100644
--- a/src/mesa/state_tracker/st_cb_readpixels.c
+++ b/src/mesa/state_tracker/st_cb_readpixels.c
@@ -26,649 +26,32 @@
**************************************************************************/
-/**
- * glReadPixels interface to pipe
- *
- * \author Brian Paul
- */
-
-
#include "main/imports.h"
-#include "main/bufferobj.h"
-#include "main/context.h"
-#include "main/image.h"
-#include "main/pack.h"
-#include "main/pbo.h"
-
-#include "pipe/p_context.h"
-#include "pipe/p_defines.h"
-#include "util/u_format.h"
-#include "util/u_inlines.h"
-#include "util/u_tile.h"
+#include "main/readpix.h"
-#include "st_debug.h"
-#include "st_context.h"
#include "st_atom.h"
+#include "st_context.h"
#include "st_cb_bitmap.h"
#include "st_cb_readpixels.h"
-#include "st_cb_fbo.h"
-
-/**
- * Special case for reading stencil buffer.
- * For color/depth we use get_tile(). For stencil, map the stencil buffer.
- */
-void
-st_read_stencil_pixels(struct gl_context *ctx, GLint x, GLint y,
- GLsizei width, GLsizei height,
- GLenum format, GLenum type,
- const struct gl_pixelstore_attrib *packing,
- GLvoid *pixels)
-{
- struct gl_framebuffer *fb = ctx->ReadBuffer;
- struct pipe_context *pipe = st_context(ctx)->pipe;
- struct st_renderbuffer *strb = st_renderbuffer(fb->_StencilBuffer);
- struct pipe_transfer *pt;
- ubyte *stmap;
- GLint j;
-
- if (strb->Base.Wrapped) {
- strb = st_renderbuffer(strb->Base.Wrapped);
- }
-
- if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
- y = ctx->DrawBuffer->Height - y - height;
- }
-
- /* Create a read transfer from the renderbuffer's texture */
-
- pt = pipe_get_transfer(pipe, strb->texture,
- strb->rtt_level,
- strb->rtt_face + strb->rtt_slice,
- PIPE_TRANSFER_READ,
- x, y, width, height);
-
- /* map the stencil buffer */
- stmap = pipe_transfer_map(pipe, pt);
-
- /* 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++) {
- GLvoid *dest;
- GLubyte sValues[MAX_WIDTH];
- GLfloat zValues[MAX_WIDTH];
- GLint srcY;
-
- if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
- srcY = height - j - 1;
- }
- else {
- srcY = j;
- }
-
- /* get stencil (and Z) values */
- switch (pt->resource->format) {
- case PIPE_FORMAT_S8_UINT:
- {
- const ubyte *src = stmap + srcY * pt->stride;
- memcpy(sValues, src, width);
- }
- break;
- case PIPE_FORMAT_Z24_UNORM_S8_UINT:
- if (format == GL_DEPTH_STENCIL) {
- const uint *src = (uint *) (stmap + srcY * pt->stride);
- const GLfloat scale = 1.0f / (0xffffff);
- GLint k;
- for (k = 0; k < width; k++) {
- sValues[k] = src[k] >> 24;
- zValues[k] = (src[k] & 0xffffff) * scale;
- }
- }
- else {
- const uint *src = (uint *) (stmap + srcY * pt->stride);
- GLint k;
- for (k = 0; k < width; k++) {
- sValues[k] = src[k] >> 24;
- }
- }
- break;
- case PIPE_FORMAT_S8_UINT_Z24_UNORM:
- if (format == GL_DEPTH_STENCIL) {
- const uint *src = (uint *) (stmap + srcY * pt->stride);
- const GLfloat scale = 1.0f / (0xffffff);
- GLint k;
- for (k = 0; k < width; k++) {
- sValues[k] = src[k] & 0xff;
- zValues[k] = (src[k] >> 8) * scale;
- }
- }
- else {
- const uint *src = (uint *) (stmap + srcY * pt->stride);
- GLint k;
- for (k = 0; k < width; k++) {
- sValues[k] = src[k] & 0xff;
- }
- }
- break;
- case PIPE_FORMAT_Z32_FLOAT_S8X24_UINT:
- if (format == GL_DEPTH_STENCIL) {
- const uint *src = (uint *) (stmap + srcY * pt->stride);
- const GLfloat *srcf = (const GLfloat*)src;
- GLint k;
- for (k = 0; k < width; k++) {
- zValues[k] = srcf[k*2];
- sValues[k] = src[k*2+1] & 0xff;
- }
- }
- else {
- const uint *src = (uint *) (stmap + srcY * pt->stride);
- GLint k;
- for (k = 0; k < width; k++) {
- sValues[k] = src[k*2+1] & 0xff;
- }
- }
- break;
- default:
- assert(0);
- }
-
- /* store */
- dest = _mesa_image_address2d(packing, pixels, width, height,
- format, type, j, 0);
- if (format == GL_DEPTH_STENCIL) {
- _mesa_pack_depth_stencil_span(ctx, width, type, dest,
- zValues, sValues, packing);
- }
- else {
- _mesa_pack_stencil_span(ctx, width, type, dest, sValues, packing);
- }
- }
-
- /* unmap the stencil buffer */
- pipe_transfer_unmap(pipe, pt);
- pipe->transfer_destroy(pipe, pt);
-}
-
-
-/**
- * Return renderbuffer to use for reading color pixels for glRead/CopyPixel
- * commands.
- */
-static struct st_renderbuffer *
-st_get_color_read_renderbuffer(struct gl_context *ctx)
-{
- struct gl_framebuffer *fb = ctx->ReadBuffer;
- struct st_renderbuffer *strb =
- st_renderbuffer(fb->_ColorReadBuffer);
-
- return strb;
-}
-
-
-/**
- * Try to do glReadPixels in a fast manner for common cases.
- * \return GL_TRUE for success, GL_FALSE for failure
- */
-static GLboolean
-st_fast_readpixels(struct gl_context *ctx, struct st_renderbuffer *strb,
- GLint x, GLint y, GLsizei width, GLsizei height,
- GLenum format, GLenum type,
- const struct gl_pixelstore_attrib *pack,
- GLvoid *dest)
-{
- GLubyte alphaORoperand;
- enum combination {
- A8R8G8B8_UNORM_TO_RGBA_UBYTE,
- A8R8G8B8_UNORM_TO_RGB_UBYTE,
- A8R8G8B8_UNORM_TO_BGRA_UINT,
- A8R8G8B8_UNORM_TO_RGBA_UINT
- } combo;
-
- if (ctx->_ImageTransferState)
- return GL_FALSE;
-
- if (strb->format == PIPE_FORMAT_B8G8R8A8_UNORM) {
- alphaORoperand = 0;
- }
- else if (strb->format == PIPE_FORMAT_B8G8R8X8_UNORM ) {
- alphaORoperand = 0xff;
- }
- else {
- return GL_FALSE;
- }
-
- if (format == GL_RGBA && type == GL_UNSIGNED_BYTE) {
- combo = A8R8G8B8_UNORM_TO_RGBA_UBYTE;
- }
- else if (format == GL_RGB && type == GL_UNSIGNED_BYTE) {
- combo = A8R8G8B8_UNORM_TO_RGB_UBYTE;
- }
- else if (format == GL_BGRA && type == GL_UNSIGNED_INT_8_8_8_8_REV) {
- combo = A8R8G8B8_UNORM_TO_BGRA_UINT;
- }
- else if (format == GL_RGBA && type == GL_UNSIGNED_INT_8_8_8_8) {
- combo = A8R8G8B8_UNORM_TO_RGBA_UINT;
- }
- else {
- return GL_FALSE;
- }
-
- /*printf("st_fast_readpixels combo %d\n", (GLint) combo);*/
-
- {
- struct pipe_context *pipe = st_context(ctx)->pipe;
- struct pipe_transfer *trans;
- const GLubyte *map;
- GLubyte *dst;
- GLint row, col, dy, dstStride;
-
- if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
- /* convert GL Y to Gallium Y */
- y = strb->texture->height0 - y - height;
- }
-
- trans = pipe_get_transfer(pipe, strb->texture,
- strb->rtt_level,
- strb->rtt_face + strb->rtt_slice,
- PIPE_TRANSFER_READ,
- x, y, width, height);
- if (!trans) {
- return GL_FALSE;
- }
-
- map = pipe_transfer_map(pipe, trans);
- if (!map) {
- pipe->transfer_destroy(pipe, trans);
- return GL_FALSE;
- }
-
- /* We always write to the user/dest buffer from low addr to high addr
- * but the read order depends on renderbuffer orientation
- */
- if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
- /* read source rows from bottom to top */
- y = height - 1;
- dy = -1;
- }
- else {
- /* read source rows from top to bottom */
- y = 0;
- dy = 1;
- }
-
- dst = _mesa_image_address2d(pack, dest, width, height,
- format, type, 0, 0);
- dstStride = _mesa_image_row_stride(pack, width, format, type);
-
- switch (combo) {
- case A8R8G8B8_UNORM_TO_RGBA_UBYTE:
- for (row = 0; row < height; row++) {
- const GLubyte *src = map + y * trans->stride;
- for (col = 0; col < width; col++) {
- GLuint pixel = ((GLuint *) src)[col];
- dst[col*4+0] = (pixel >> 16) & 0xff;
- dst[col*4+1] = (pixel >> 8) & 0xff;
- dst[col*4+2] = (pixel >> 0) & 0xff;
- dst[col*4+3] = ((pixel >> 24) & 0xff) | alphaORoperand;
- }
- dst += dstStride;
- y += dy;
- }
- break;
- case A8R8G8B8_UNORM_TO_RGB_UBYTE:
- for (row = 0; row < height; row++) {
- const GLubyte *src = map + y * trans->stride;
- for (col = 0; col < width; col++) {
- GLuint pixel = ((GLuint *) src)[col];
- dst[col*3+0] = (pixel >> 16) & 0xff;
- dst[col*3+1] = (pixel >> 8) & 0xff;
- dst[col*3+2] = (pixel >> 0) & 0xff;
- }
- dst += dstStride;
- y += dy;
- }
- break;
- case A8R8G8B8_UNORM_TO_BGRA_UINT:
- for (row = 0; row < height; row++) {
- const GLubyte *src = map + y * trans->stride;
- memcpy(dst, src, 4 * width);
- if (alphaORoperand) {
- assert(alphaORoperand == 0xff);
- for (col = 0; col < width; col++) {
- dst[col*4+3] = 0xff;
- }
- }
- dst += dstStride;
- y += dy;
- }
- break;
- case A8R8G8B8_UNORM_TO_RGBA_UINT:
- for (row = 0; row < height; row++) {
- const GLubyte *src = map + y * trans->stride;
- for (col = 0; col < width; col++) {
- GLuint pixel = ((GLuint *) src)[col];
- dst[col*4+0] = ((pixel >> 24) & 0xff) | alphaORoperand;
- dst[col*4+1] = (pixel >> 0) & 0xff;
- dst[col*4+2] = (pixel >> 8) & 0xff;
- dst[col*4+3] = (pixel >> 16) & 0xff;
- }
- dst += dstStride;
- y += dy;
- }
- break;
- default:
- ; /* nothing */
- }
-
- pipe_transfer_unmap(pipe, trans);
- pipe->transfer_destroy(pipe, trans);
- }
-
- return GL_TRUE;
-}
/**
- * Do glReadPixels by getting rows from the framebuffer transfer with
- * get_tile(). Convert to requested format/type with Mesa image routines.
- * Image transfer ops are done in software too.
+ * The only special thing we need to do for the state tracker's
+ * glReadPixels is to validate state (to be sure we have up-to-date
+ * framebuffer surfaces) and flush the bitmap cache prior to reading.
*/
static void
-st_readpixels(struct gl_context *ctx, GLint x, GLint y, GLsizei width, GLsizei height,
+st_readpixels(struct gl_context *ctx, GLint x, GLint y,
+ GLsizei width, GLsizei height,
GLenum format, GLenum type,
const struct gl_pixelstore_attrib *pack,
GLvoid *dest)
{
struct st_context *st = st_context(ctx);
- struct pipe_context *pipe = st->pipe;
- GLfloat (*temp)[4];
- GLbitfield transferOps = ctx->_ImageTransferState;
- GLsizei i, j;
- GLint yStep, dfStride;
- GLfloat *df;
- GLuint *dui;
- GLint *di;
- struct st_renderbuffer *strb;
- struct gl_pixelstore_attrib clippedPacking = *pack;
- struct pipe_transfer *trans;
- enum pipe_format pformat;
-
- assert(ctx->ReadBuffer->Width > 0);
st_validate_state(st);
-
- /* 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 transfer is totally outside the window bounds */
- return;
- }
-
st_flush_bitmap_cache(st);
-
- dest = _mesa_map_pbo_dest(ctx, &clippedPacking, dest);
- if (!dest)
- return;
-
- if (format == GL_STENCIL_INDEX ||
- format == GL_DEPTH_STENCIL) {
- st_read_stencil_pixels(ctx, x, y, width, height,
- format, type, pack, dest);
- return;
- }
- else if (format == GL_DEPTH_COMPONENT) {
- strb = st_renderbuffer(ctx->ReadBuffer->_DepthBuffer);
- if (strb->Base.Wrapped) {
- strb = st_renderbuffer(strb->Base.Wrapped);
- }
- }
- else {
- /* Read color buffer */
- strb = st_get_color_read_renderbuffer(ctx);
- }
-
- if (!strb)
- return;
-
- /* try a fast-path readpixels before anything else */
- if (st_fast_readpixels(ctx, strb, x, y, width, height,
- format, type, pack, dest)) {
- /* success! */
- _mesa_unmap_pbo_dest(ctx, &clippedPacking);
- return;
- }
-
- /* allocate temp pixel row buffer */
- temp = (GLfloat (*)[4]) malloc(4 * width * sizeof(GLfloat));
- if (!temp) {
- _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
- return;
- }
-
- if(ctx->Color._ClampReadColor)
- transferOps |= IMAGE_CLAMP_BIT;
-
- if (format == GL_RGBA && type == GL_FLOAT && !transferOps) {
- /* write tile(row) directly into user's buffer */
- df = (GLfloat *) _mesa_image_address2d(&clippedPacking, dest, width,
- height, format, type, 0, 0);
- dfStride = width * 4;
- }
- else {
- /* write tile(row) into temp row buffer */
- df = (GLfloat *)temp;
- dfStride = 0;
- }
-
- dui = (GLuint *)df;
- di = (GLint *)df;
-
- if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
- /* convert GL Y to Gallium Y */
- y = strb->Base.Height - y - height;
- }
-
- /* Create a read transfer from the renderbuffer's texture */
- trans = pipe_get_transfer(pipe, strb->texture,
- strb->rtt_level, /* level */
- strb->rtt_face + strb->rtt_slice, /* layer */
- PIPE_TRANSFER_READ,
- x, y, width, height);
-
- /* determine bottom-to-top vs. top-to-bottom order */
- if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
- y = height - 1;
- yStep = -1;
- }
- else {
- y = 0;
- yStep = 1;
- }
-
- /* possibly convert sRGB format to linear RGB format */
- pformat = util_format_linear(trans->resource->format);
-
- if (ST_DEBUG & DEBUG_FALLBACK)
- debug_printf("%s: fallback processing\n", __FUNCTION__);
-
- /*
- * Copy pixels from pipe_transfer to user memory
- */
- {
- /* dest of first pixel in client memory */
- GLubyte *dst = _mesa_image_address2d(&clippedPacking, dest, width,
- height, format, type, 0, 0);
- /* dest row stride */
- const GLint dstStride = _mesa_image_row_stride(&clippedPacking, width,
- format, type);
-
- if (pformat == PIPE_FORMAT_Z24_UNORM_S8_UINT ||
- pformat == PIPE_FORMAT_Z24X8_UNORM) {
- if (format == GL_DEPTH_COMPONENT) {
- for (i = 0; i < height; i++) {
- GLuint ztemp[MAX_WIDTH];
- GLfloat zfloat[MAX_WIDTH];
- const double scale = 1.0 / ((1 << 24) - 1);
- pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
- y += yStep;
- for (j = 0; j < width; j++) {
- zfloat[j] = (float) (scale * (ztemp[j] & 0xffffff));
- }
- _mesa_pack_depth_span(ctx, width, dst, type,
- zfloat, &clippedPacking);
- dst += dstStride;
- }
- }
- else {
- /* XXX: unreachable code -- should be before st_read_stencil_pixels */
- assert(format == GL_DEPTH_STENCIL_EXT);
- for (i = 0; i < height; i++) {
- GLuint *zshort = (GLuint *)dst;
- pipe_get_tile_raw(pipe, trans, 0, y, width, 1, dst, 0);
- y += yStep;
- /* Reverse into 24/8 */
- for (j = 0; j < width; j++) {
- zshort[j] = (zshort[j] << 8) | (zshort[j] >> 24);
- }
- dst += dstStride;
- }
- }
- }
- else if (pformat == PIPE_FORMAT_S8_UINT_Z24_UNORM ||
- pformat == PIPE_FORMAT_X8Z24_UNORM) {
- if (format == GL_DEPTH_COMPONENT) {
- for (i = 0; i < height; i++) {
- GLuint ztemp[MAX_WIDTH];
- GLfloat zfloat[MAX_WIDTH];
- const double scale = 1.0 / ((1 << 24) - 1);
- pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
- y += yStep;
- for (j = 0; j < width; j++) {
- zfloat[j] = (float) (scale * ((ztemp[j] >> 8) & 0xffffff));
- }
- _mesa_pack_depth_span(ctx, width, dst, type,
- zfloat, &clippedPacking);
- dst += dstStride;
- }
- }
- else {
- /* XXX: unreachable code -- should be before st_read_stencil_pixels */
- assert(format == GL_DEPTH_STENCIL_EXT);
- for (i = 0; i < height; i++) {
- pipe_get_tile_raw(pipe, trans, 0, y, width, 1, dst, 0);
- y += yStep;
- dst += dstStride;
- }
- }
- }
- else if (pformat == PIPE_FORMAT_Z16_UNORM) {
- for (i = 0; i < height; i++) {
- GLushort ztemp[MAX_WIDTH];
- GLfloat zfloat[MAX_WIDTH];
- const double scale = 1.0 / 0xffff;
- pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
- y += yStep;
- for (j = 0; j < width; j++) {
- zfloat[j] = (float) (scale * ztemp[j]);
- }
- _mesa_pack_depth_span(ctx, width, dst, type,
- zfloat, &clippedPacking);
- dst += dstStride;
- }
- }
- else if (pformat == PIPE_FORMAT_Z32_UNORM) {
- for (i = 0; i < height; i++) {
- GLuint ztemp[MAX_WIDTH];
- GLfloat zfloat[MAX_WIDTH];
- const double scale = 1.0 / 0xffffffff;
- pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
- y += yStep;
- for (j = 0; j < width; j++) {
- zfloat[j] = (float) (scale * ztemp[j]);
- }
- _mesa_pack_depth_span(ctx, width, dst, type,
- zfloat, &clippedPacking);
- dst += dstStride;
- }
- }
- else if (pformat == PIPE_FORMAT_Z32_FLOAT) {
- for (i = 0; i < height; i++) {
- GLfloat zfloat[MAX_WIDTH];
- pipe_get_tile_raw(pipe, trans, 0, y, width, 1, zfloat, 0);
- y += yStep;
- _mesa_pack_depth_span(ctx, width, dst, type,
- zfloat, &clippedPacking);
- dst += dstStride;
- }
- }
- else if (pformat == PIPE_FORMAT_Z32_FLOAT_S8X24_UINT) {
- assert(format == GL_DEPTH_COMPONENT);
- for (i = 0; i < height; i++) {
- GLfloat zfloat[MAX_WIDTH]; /* Z32 */
- GLfloat zfloat2[MAX_WIDTH*2]; /* Z32X32 */
- pipe_get_tile_raw(pipe, trans, 0, y, width, 1, zfloat2, 0);
- y += yStep;
- for (j = 0; j < width; j++) {
- zfloat[j] = zfloat2[j*2];
- }
- _mesa_pack_depth_span(ctx, width, dst, type,
- zfloat, &clippedPacking);
- dst += dstStride;
- }
- }
- else if (util_format_is_pure_sint(pformat)) {
- for (i = 0; i < height; i++) {
- if (type == GL_UNSIGNED_INT)
- pipe_get_tile_ui_format(pipe, trans, 0, y, width, 1,
- pformat, dui);
- else
- pipe_get_tile_i_format(pipe, trans, 0, y, width, 1,
- pformat, di);
- y += yStep;
- if (!dfStride) {
- _mesa_pack_rgba_span_int(ctx, width, (GLuint (*)[4])temp,
- format, type, dst);
- dst += dstStride;
- }
- }
- } else if (util_format_is_pure_uint(pformat)) {
- for (i = 0; i < height; i++) {
- if (type == GL_UNSIGNED_INT)
- pipe_get_tile_ui_format(pipe, trans, 0, y, width, 1,
- pformat, dui);
- else
- pipe_get_tile_i_format(pipe, trans, 0, y, width, 1,
- pformat, di);
- y += yStep;
- df += dfStride;
- if (!dfStride) {
- _mesa_pack_rgba_span_int(ctx, width, (GLuint (*)[4])temp,
- format, type, dst);
- dst += dstStride;
- }
- }
- } else {
- /* RGBA format */
- /* Do a row at a time to flip image data vertically */
- for (i = 0; i < height; i++) {
- pipe_get_tile_rgba_format(pipe, trans, 0, y, width, 1,
- pformat, df);
- y += yStep;
- df += dfStride;
- if (!dfStride) {
- _mesa_pack_rgba_span_float(ctx, width, temp, format, type, dst,
- &clippedPacking, transferOps);
- dst += dstStride;
- }
- }
- }
- }
-
- free(temp);
-
- pipe->transfer_destroy(pipe, trans);
-
- _mesa_unmap_pbo_dest(ctx, &clippedPacking);
+ _mesa_readpixels(ctx, x, y, width, height, format, type, pack, dest);
}
diff --git a/src/mesa/state_tracker/st_cb_readpixels.h b/src/mesa/state_tracker/st_cb_readpixels.h
index cbfe3f2eee7..fdc85478297 100644
--- a/src/mesa/state_tracker/st_cb_readpixels.h
+++ b/src/mesa/state_tracker/st_cb_readpixels.h
@@ -32,15 +32,6 @@
#include "main/glheader.h"
struct dd_function_table;
-struct gl_context;
-struct gl_pixelstore_attrib;
-
-extern void
-st_read_stencil_pixels(struct gl_context *ctx, GLint x, GLint y,
- GLsizei width, GLsizei height,
- GLenum format, GLenum type,
- const struct gl_pixelstore_attrib *packing,
- GLvoid *pixels);
extern void
st_init_readpixels_functions(struct dd_function_table *functions);