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-rw-r--r--src/mesa/main/image.c526
1 files changed, 519 insertions, 7 deletions
diff --git a/src/mesa/main/image.c b/src/mesa/main/image.c
index 8034daecae2..bd38e0c3d8c 100644
--- a/src/mesa/main/image.c
+++ b/src/mesa/main/image.c
@@ -2,7 +2,7 @@
* Mesa 3-D graphics library
* Version: 7.1
*
- * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
+ * Copyright (C) 1999-2008 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"),
@@ -34,7 +34,6 @@
#include "context.h"
#include "image.h"
#include "imports.h"
-#include "histogram.h"
#include "macros.h"
#include "pixel.h"
@@ -1011,6 +1010,488 @@ _mesa_pack_bitmap( GLint width, GLint height, const GLubyte *source,
}
+/**********************************************************************/
+/***** Pixel processing functions ******/
+/**********************************************************************/
+
+/*
+ * Apply scale and bias factors to an array of RGBA pixels.
+ */
+void
+_mesa_scale_and_bias_rgba(GLuint n, GLfloat rgba[][4],
+ GLfloat rScale, GLfloat gScale,
+ GLfloat bScale, GLfloat aScale,
+ GLfloat rBias, GLfloat gBias,
+ GLfloat bBias, GLfloat aBias)
+{
+ if (rScale != 1.0 || rBias != 0.0) {
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ rgba[i][RCOMP] = rgba[i][RCOMP] * rScale + rBias;
+ }
+ }
+ if (gScale != 1.0 || gBias != 0.0) {
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ rgba[i][GCOMP] = rgba[i][GCOMP] * gScale + gBias;
+ }
+ }
+ if (bScale != 1.0 || bBias != 0.0) {
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ rgba[i][BCOMP] = rgba[i][BCOMP] * bScale + bBias;
+ }
+ }
+ if (aScale != 1.0 || aBias != 0.0) {
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ rgba[i][ACOMP] = rgba[i][ACOMP] * aScale + aBias;
+ }
+ }
+}
+
+
+/*
+ * Apply pixel mapping to an array of floating point RGBA pixels.
+ */
+void
+_mesa_map_rgba( const GLcontext *ctx, GLuint n, GLfloat rgba[][4] )
+{
+ const GLfloat rscale = (GLfloat) (ctx->PixelMaps.RtoR.Size - 1);
+ const GLfloat gscale = (GLfloat) (ctx->PixelMaps.GtoG.Size - 1);
+ const GLfloat bscale = (GLfloat) (ctx->PixelMaps.BtoB.Size - 1);
+ const GLfloat ascale = (GLfloat) (ctx->PixelMaps.AtoA.Size - 1);
+ const GLfloat *rMap = ctx->PixelMaps.RtoR.Map;
+ const GLfloat *gMap = ctx->PixelMaps.GtoG.Map;
+ const GLfloat *bMap = ctx->PixelMaps.BtoB.Map;
+ const GLfloat *aMap = ctx->PixelMaps.AtoA.Map;
+ GLuint i;
+ for (i=0;i<n;i++) {
+ GLfloat r = CLAMP(rgba[i][RCOMP], 0.0F, 1.0F);
+ GLfloat g = CLAMP(rgba[i][GCOMP], 0.0F, 1.0F);
+ GLfloat b = CLAMP(rgba[i][BCOMP], 0.0F, 1.0F);
+ GLfloat a = CLAMP(rgba[i][ACOMP], 0.0F, 1.0F);
+ rgba[i][RCOMP] = rMap[IROUND(r * rscale)];
+ rgba[i][GCOMP] = gMap[IROUND(g * gscale)];
+ rgba[i][BCOMP] = bMap[IROUND(b * bscale)];
+ rgba[i][ACOMP] = aMap[IROUND(a * ascale)];
+ }
+}
+
+
+/*
+ * Apply the color matrix and post color matrix scaling and biasing.
+ */
+void
+_mesa_transform_rgba(const GLcontext *ctx, GLuint n, GLfloat rgba[][4])
+{
+ const GLfloat rs = ctx->Pixel.PostColorMatrixScale[0];
+ const GLfloat rb = ctx->Pixel.PostColorMatrixBias[0];
+ const GLfloat gs = ctx->Pixel.PostColorMatrixScale[1];
+ const GLfloat gb = ctx->Pixel.PostColorMatrixBias[1];
+ const GLfloat bs = ctx->Pixel.PostColorMatrixScale[2];
+ const GLfloat bb = ctx->Pixel.PostColorMatrixBias[2];
+ const GLfloat as = ctx->Pixel.PostColorMatrixScale[3];
+ const GLfloat ab = ctx->Pixel.PostColorMatrixBias[3];
+ const GLfloat *m = ctx->ColorMatrixStack.Top->m;
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ const GLfloat r = rgba[i][RCOMP];
+ const GLfloat g = rgba[i][GCOMP];
+ const GLfloat b = rgba[i][BCOMP];
+ const GLfloat a = rgba[i][ACOMP];
+ rgba[i][RCOMP] = (m[0] * r + m[4] * g + m[ 8] * b + m[12] * a) * rs + rb;
+ rgba[i][GCOMP] = (m[1] * r + m[5] * g + m[ 9] * b + m[13] * a) * gs + gb;
+ rgba[i][BCOMP] = (m[2] * r + m[6] * g + m[10] * b + m[14] * a) * bs + bb;
+ rgba[i][ACOMP] = (m[3] * r + m[7] * g + m[11] * b + m[15] * a) * as + ab;
+ }
+}
+
+
+/**
+ * Apply a color table lookup to an array of floating point RGBA colors.
+ */
+void
+_mesa_lookup_rgba_float(const struct gl_color_table *table,
+ GLuint n, GLfloat rgba[][4])
+{
+ const GLint max = table->Size - 1;
+ const GLfloat scale = (GLfloat) max;
+ const GLfloat *lut = table->TableF;
+ GLuint i;
+
+ if (!table->TableF || table->Size == 0)
+ return;
+
+ switch (table->_BaseFormat) {
+ case GL_INTENSITY:
+ /* replace RGBA with I */
+ for (i = 0; i < n; i++) {
+ GLint j = IROUND(rgba[i][RCOMP] * scale);
+ GLfloat c = lut[CLAMP(j, 0, max)];
+ rgba[i][RCOMP] =
+ rgba[i][GCOMP] =
+ rgba[i][BCOMP] =
+ rgba[i][ACOMP] = c;
+ }
+ break;
+ case GL_LUMINANCE:
+ /* replace RGB with L */
+ for (i = 0; i < n; i++) {
+ GLint j = IROUND(rgba[i][RCOMP] * scale);
+ GLfloat c = lut[CLAMP(j, 0, max)];
+ rgba[i][RCOMP] =
+ rgba[i][GCOMP] =
+ rgba[i][BCOMP] = c;
+ }
+ break;
+ case GL_ALPHA:
+ /* replace A with A */
+ for (i = 0; i < n; i++) {
+ GLint j = IROUND(rgba[i][ACOMP] * scale);
+ rgba[i][ACOMP] = lut[CLAMP(j, 0, max)];
+ }
+ break;
+ case GL_LUMINANCE_ALPHA:
+ /* replace RGBA with LLLA */
+ for (i = 0; i < n; i++) {
+ GLint jL = IROUND(rgba[i][RCOMP] * scale);
+ GLint jA = IROUND(rgba[i][ACOMP] * scale);
+ GLfloat luminance, alpha;
+ jL = CLAMP(jL, 0, max);
+ jA = CLAMP(jA, 0, max);
+ luminance = lut[jL * 2 + 0];
+ alpha = lut[jA * 2 + 1];
+ rgba[i][RCOMP] =
+ rgba[i][GCOMP] =
+ rgba[i][BCOMP] = luminance;
+ rgba[i][ACOMP] = alpha;;
+ }
+ break;
+ case GL_RGB:
+ /* replace RGB with RGB */
+ for (i = 0; i < n; i++) {
+ GLint jR = IROUND(rgba[i][RCOMP] * scale);
+ GLint jG = IROUND(rgba[i][GCOMP] * scale);
+ GLint jB = IROUND(rgba[i][BCOMP] * scale);
+ jR = CLAMP(jR, 0, max);
+ jG = CLAMP(jG, 0, max);
+ jB = CLAMP(jB, 0, max);
+ rgba[i][RCOMP] = lut[jR * 3 + 0];
+ rgba[i][GCOMP] = lut[jG * 3 + 1];
+ rgba[i][BCOMP] = lut[jB * 3 + 2];
+ }
+ break;
+ case GL_RGBA:
+ /* replace RGBA with RGBA */
+ for (i = 0; i < n; i++) {
+ GLint jR = IROUND(rgba[i][RCOMP] * scale);
+ GLint jG = IROUND(rgba[i][GCOMP] * scale);
+ GLint jB = IROUND(rgba[i][BCOMP] * scale);
+ GLint jA = IROUND(rgba[i][ACOMP] * scale);
+ jR = CLAMP(jR, 0, max);
+ jG = CLAMP(jG, 0, max);
+ jB = CLAMP(jB, 0, max);
+ jA = CLAMP(jA, 0, max);
+ rgba[i][RCOMP] = lut[jR * 4 + 0];
+ rgba[i][GCOMP] = lut[jG * 4 + 1];
+ rgba[i][BCOMP] = lut[jB * 4 + 2];
+ rgba[i][ACOMP] = lut[jA * 4 + 3];
+ }
+ break;
+ default:
+ _mesa_problem(NULL, "Bad format in _mesa_lookup_rgba_float");
+ return;
+ }
+}
+
+
+
+/**
+ * Apply a color table lookup to an array of ubyte/RGBA colors.
+ */
+void
+_mesa_lookup_rgba_ubyte(const struct gl_color_table *table,
+ GLuint n, GLubyte rgba[][4])
+{
+ const GLubyte *lut = table->TableUB;
+ const GLfloat scale = (GLfloat) (table->Size - 1) / (GLfloat)255.0;
+ GLuint i;
+
+ if (!table->TableUB || table->Size == 0)
+ return;
+
+ switch (table->_BaseFormat) {
+ case GL_INTENSITY:
+ /* replace RGBA with I */
+ if (table->Size == 256) {
+ for (i = 0; i < n; i++) {
+ const GLubyte c = lut[rgba[i][RCOMP]];
+ rgba[i][RCOMP] =
+ rgba[i][GCOMP] =
+ rgba[i][BCOMP] =
+ rgba[i][ACOMP] = c;
+ }
+ }
+ else {
+ for (i = 0; i < n; i++) {
+ GLint j = IROUND((GLfloat) rgba[i][RCOMP] * scale);
+ rgba[i][RCOMP] =
+ rgba[i][GCOMP] =
+ rgba[i][BCOMP] =
+ rgba[i][ACOMP] = lut[j];
+ }
+ }
+ break;
+ case GL_LUMINANCE:
+ /* replace RGB with L */
+ if (table->Size == 256) {
+ for (i = 0; i < n; i++) {
+ const GLubyte c = lut[rgba[i][RCOMP]];
+ rgba[i][RCOMP] =
+ rgba[i][GCOMP] =
+ rgba[i][BCOMP] = c;
+ }
+ }
+ else {
+ for (i = 0; i < n; i++) {
+ GLint j = IROUND((GLfloat) rgba[i][RCOMP] * scale);
+ rgba[i][RCOMP] =
+ rgba[i][GCOMP] =
+ rgba[i][BCOMP] = lut[j];
+ }
+ }
+ break;
+ case GL_ALPHA:
+ /* replace A with A */
+ if (table->Size == 256) {
+ for (i = 0; i < n; i++) {
+ rgba[i][ACOMP] = lut[rgba[i][ACOMP]];
+ }
+ }
+ else {
+ for (i = 0; i < n; i++) {
+ GLint j = IROUND((GLfloat) rgba[i][ACOMP] * scale);
+ rgba[i][ACOMP] = lut[j];
+ }
+ }
+ break;
+ case GL_LUMINANCE_ALPHA:
+ /* replace RGBA with LLLA */
+ if (table->Size == 256) {
+ for (i = 0; i < n; i++) {
+ GLubyte l = lut[rgba[i][RCOMP] * 2 + 0];
+ GLubyte a = lut[rgba[i][ACOMP] * 2 + 1];;
+ rgba[i][RCOMP] =
+ rgba[i][GCOMP] =
+ rgba[i][BCOMP] = l;
+ rgba[i][ACOMP] = a;
+ }
+ }
+ else {
+ for (i = 0; i < n; i++) {
+ GLint jL = IROUND((GLfloat) rgba[i][RCOMP] * scale);
+ GLint jA = IROUND((GLfloat) rgba[i][ACOMP] * scale);
+ GLubyte luminance = lut[jL * 2 + 0];
+ GLubyte alpha = lut[jA * 2 + 1];
+ rgba[i][RCOMP] =
+ rgba[i][GCOMP] =
+ rgba[i][BCOMP] = luminance;
+ rgba[i][ACOMP] = alpha;
+ }
+ }
+ break;
+ case GL_RGB:
+ if (table->Size == 256) {
+ for (i = 0; i < n; i++) {
+ rgba[i][RCOMP] = lut[rgba[i][RCOMP] * 3 + 0];
+ rgba[i][GCOMP] = lut[rgba[i][GCOMP] * 3 + 1];
+ rgba[i][BCOMP] = lut[rgba[i][BCOMP] * 3 + 2];
+ }
+ }
+ else {
+ for (i = 0; i < n; i++) {
+ GLint jR = IROUND((GLfloat) rgba[i][RCOMP] * scale);
+ GLint jG = IROUND((GLfloat) rgba[i][GCOMP] * scale);
+ GLint jB = IROUND((GLfloat) rgba[i][BCOMP] * scale);
+ rgba[i][RCOMP] = lut[jR * 3 + 0];
+ rgba[i][GCOMP] = lut[jG * 3 + 1];
+ rgba[i][BCOMP] = lut[jB * 3 + 2];
+ }
+ }
+ break;
+ case GL_RGBA:
+ if (table->Size == 256) {
+ for (i = 0; i < n; i++) {
+ rgba[i][RCOMP] = lut[rgba[i][RCOMP] * 4 + 0];
+ rgba[i][GCOMP] = lut[rgba[i][GCOMP] * 4 + 1];
+ rgba[i][BCOMP] = lut[rgba[i][BCOMP] * 4 + 2];
+ rgba[i][ACOMP] = lut[rgba[i][ACOMP] * 4 + 3];
+ }
+ }
+ else {
+ for (i = 0; i < n; i++) {
+ GLint jR = IROUND((GLfloat) rgba[i][RCOMP] * scale);
+ GLint jG = IROUND((GLfloat) rgba[i][GCOMP] * scale);
+ GLint jB = IROUND((GLfloat) rgba[i][BCOMP] * scale);
+ GLint jA = IROUND((GLfloat) rgba[i][ACOMP] * scale);
+ CLAMPED_FLOAT_TO_CHAN(rgba[i][RCOMP], lut[jR * 4 + 0]);
+ CLAMPED_FLOAT_TO_CHAN(rgba[i][GCOMP], lut[jG * 4 + 1]);
+ CLAMPED_FLOAT_TO_CHAN(rgba[i][BCOMP], lut[jB * 4 + 2]);
+ CLAMPED_FLOAT_TO_CHAN(rgba[i][ACOMP], lut[jA * 4 + 3]);
+ }
+ }
+ break;
+ default:
+ _mesa_problem(NULL, "Bad format in _mesa_lookup_rgba_chan");
+ return;
+ }
+}
+
+
+
+/*
+ * Map color indexes to float rgba values.
+ */
+void
+_mesa_map_ci_to_rgba( const GLcontext *ctx, GLuint n,
+ const GLuint index[], GLfloat rgba[][4] )
+{
+ GLuint rmask = ctx->PixelMaps.ItoR.Size - 1;
+ GLuint gmask = ctx->PixelMaps.ItoG.Size - 1;
+ GLuint bmask = ctx->PixelMaps.ItoB.Size - 1;
+ GLuint amask = ctx->PixelMaps.ItoA.Size - 1;
+ const GLfloat *rMap = ctx->PixelMaps.ItoR.Map;
+ const GLfloat *gMap = ctx->PixelMaps.ItoG.Map;
+ const GLfloat *bMap = ctx->PixelMaps.ItoB.Map;
+ const GLfloat *aMap = ctx->PixelMaps.ItoA.Map;
+ GLuint i;
+ for (i=0;i<n;i++) {
+ rgba[i][RCOMP] = rMap[index[i] & rmask];
+ rgba[i][GCOMP] = gMap[index[i] & gmask];
+ rgba[i][BCOMP] = bMap[index[i] & bmask];
+ rgba[i][ACOMP] = aMap[index[i] & amask];
+ }
+}
+
+
+/**
+ * Map ubyte color indexes to ubyte/RGBA values.
+ */
+void
+_mesa_map_ci8_to_rgba8(const GLcontext *ctx, GLuint n, const GLubyte index[],
+ GLubyte rgba[][4])
+{
+ GLuint rmask = ctx->PixelMaps.ItoR.Size - 1;
+ GLuint gmask = ctx->PixelMaps.ItoG.Size - 1;
+ GLuint bmask = ctx->PixelMaps.ItoB.Size - 1;
+ GLuint amask = ctx->PixelMaps.ItoA.Size - 1;
+ const GLubyte *rMap = ctx->PixelMaps.ItoR.Map8;
+ const GLubyte *gMap = ctx->PixelMaps.ItoG.Map8;
+ const GLubyte *bMap = ctx->PixelMaps.ItoB.Map8;
+ const GLubyte *aMap = ctx->PixelMaps.ItoA.Map8;
+ GLuint i;
+ for (i=0;i<n;i++) {
+ rgba[i][RCOMP] = rMap[index[i] & rmask];
+ rgba[i][GCOMP] = gMap[index[i] & gmask];
+ rgba[i][BCOMP] = bMap[index[i] & bmask];
+ rgba[i][ACOMP] = aMap[index[i] & amask];
+ }
+}
+
+
+void
+_mesa_scale_and_bias_depth(const GLcontext *ctx, GLuint n,
+ GLfloat depthValues[])
+{
+ const GLfloat scale = ctx->Pixel.DepthScale;
+ const GLfloat bias = ctx->Pixel.DepthBias;
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ GLfloat d = depthValues[i] * scale + bias;
+ depthValues[i] = CLAMP(d, 0.0F, 1.0F);
+ }
+}
+
+
+void
+_mesa_scale_and_bias_depth_uint(const GLcontext *ctx, GLuint n,
+ GLuint depthValues[])
+{
+ const GLdouble max = (double) 0xffffffff;
+ const GLdouble scale = ctx->Pixel.DepthScale;
+ const GLdouble bias = ctx->Pixel.DepthBias * max;
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ GLdouble d = (GLdouble) depthValues[i] * scale + bias;
+ d = CLAMP(d, 0.0, max);
+ depthValues[i] = (GLuint) d;
+ }
+}
+
+
+
+/*
+ * Update the min/max values from an array of fragment colors.
+ */
+static void
+update_minmax(GLcontext *ctx, GLuint n, const GLfloat rgba[][4])
+{
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ /* update mins */
+ if (rgba[i][RCOMP] < ctx->MinMax.Min[RCOMP])
+ ctx->MinMax.Min[RCOMP] = rgba[i][RCOMP];
+ if (rgba[i][GCOMP] < ctx->MinMax.Min[GCOMP])
+ ctx->MinMax.Min[GCOMP] = rgba[i][GCOMP];
+ if (rgba[i][BCOMP] < ctx->MinMax.Min[BCOMP])
+ ctx->MinMax.Min[BCOMP] = rgba[i][BCOMP];
+ if (rgba[i][ACOMP] < ctx->MinMax.Min[ACOMP])
+ ctx->MinMax.Min[ACOMP] = rgba[i][ACOMP];
+
+ /* update maxs */
+ if (rgba[i][RCOMP] > ctx->MinMax.Max[RCOMP])
+ ctx->MinMax.Max[RCOMP] = rgba[i][RCOMP];
+ if (rgba[i][GCOMP] > ctx->MinMax.Max[GCOMP])
+ ctx->MinMax.Max[GCOMP] = rgba[i][GCOMP];
+ if (rgba[i][BCOMP] > ctx->MinMax.Max[BCOMP])
+ ctx->MinMax.Max[BCOMP] = rgba[i][BCOMP];
+ if (rgba[i][ACOMP] > ctx->MinMax.Max[ACOMP])
+ ctx->MinMax.Max[ACOMP] = rgba[i][ACOMP];
+ }
+}
+
+
+/*
+ * Update the histogram values from an array of fragment colors.
+ */
+static void
+update_histogram(GLcontext *ctx, GLuint n, const GLfloat rgba[][4])
+{
+ const GLint max = ctx->Histogram.Width - 1;
+ GLfloat w = (GLfloat) max;
+ GLuint i;
+
+ if (ctx->Histogram.Width == 0)
+ return;
+
+ for (i = 0; i < n; i++) {
+ GLint ri = IROUND(rgba[i][RCOMP] * w);
+ GLint gi = IROUND(rgba[i][GCOMP] * w);
+ GLint bi = IROUND(rgba[i][BCOMP] * w);
+ GLint ai = IROUND(rgba[i][ACOMP] * w);
+ ri = CLAMP(ri, 0, max);
+ gi = CLAMP(gi, 0, max);
+ bi = CLAMP(bi, 0, max);
+ ai = CLAMP(ai, 0, max);
+ ctx->Histogram.Count[ri][RCOMP]++;
+ ctx->Histogram.Count[gi][GCOMP]++;
+ ctx->Histogram.Count[bi][BCOMP]++;
+ ctx->Histogram.Count[ai][ACOMP]++;
+ }
+}
+
+
/**
* Apply various pixel transfer operations to an array of RGBA pixels
* as indicated by the transferOps bitmask
@@ -1066,11 +1547,11 @@ _mesa_apply_rgba_transfer_ops(GLcontext *ctx, GLbitfield transferOps,
}
/* update histogram count */
if (transferOps & IMAGE_HISTOGRAM_BIT) {
- _mesa_update_histogram(ctx, n, (CONST GLfloat (*)[4]) rgba);
+ update_histogram(ctx, n, (CONST GLfloat (*)[4]) rgba);
}
/* update min/max values */
if (transferOps & IMAGE_MIN_MAX_BIT) {
- _mesa_update_minmax(ctx, n, (CONST GLfloat (*)[4]) rgba);
+ update_minmax(ctx, n, (CONST GLfloat (*)[4]) rgba);
}
/* clamping to [0,1] */
if (transferOps & IMAGE_CLAMP_BIT) {
@@ -1169,7 +1650,7 @@ _mesa_apply_stencil_transfer_ops(const GLcontext *ctx, GLuint n,
GLuint mask = ctx->PixelMaps.StoS.Size - 1;
GLuint i;
for (i = 0; i < n; i++) {
- stencil[i] = ctx->PixelMaps.StoS.Map[ stencil[i] & mask ];
+ stencil[i] = (GLstencil)ctx->PixelMaps.StoS.Map[ stencil[i] & mask ];
}
}
}
@@ -3680,7 +4161,7 @@ _mesa_unpack_stencil_span( const GLcontext *ctx, GLuint n,
const GLuint mask = ctx->PixelMaps.StoS.Size - 1;
GLuint i;
for (i = 0; i < n; i++) {
- indexes[i] = ctx->PixelMaps.StoS.Map[ indexes[i] & mask ];
+ indexes[i] = (GLuint)ctx->PixelMaps.StoS.Map[ indexes[i] & mask ];
}
}
@@ -4032,7 +4513,7 @@ _mesa_unpack_depth_span( const GLcontext *ctx, GLuint n,
if (needClamp) {
GLuint i;
for (i = 0; i < n; i++) {
- depthValues[i] = CLAMP(depthValues[i], 0.0, 1.0);
+ depthValues[i] = (GLfloat)CLAMP(depthValues[i], 0.0, 1.0);
}
}
@@ -4622,6 +5103,37 @@ _mesa_clip_readpixels(const GLcontext *ctx,
/**
+ * Do clipping for a glCopyTexSubImage call.
+ * The framebuffer source region might extend outside the framebuffer
+ * bounds. Clip the source region against the framebuffer bounds and
+ * adjust the texture/dest position and size accordingly.
+ *
+ * \return GL_FALSE if region is totally clipped, GL_TRUE otherwise.
+ */
+GLboolean
+_mesa_clip_copytexsubimage(const GLcontext *ctx,
+ GLint *destX, GLint *destY,
+ GLint *srcX, GLint *srcY,
+ GLsizei *width, GLsizei *height)
+{
+ const struct gl_framebuffer *fb = ctx->ReadBuffer;
+ const GLint srcX0 = *srcX, srcY0 = *srcY;
+
+ if (_mesa_clip_to_region(0, 0, fb->Width, fb->Height,
+ srcX, srcY, width, height)) {
+ *destX = *destX + *srcX - srcX0;
+ *destY = *destY + *srcY - srcY0;
+
+ return GL_TRUE;
+ }
+ else {
+ return GL_FALSE;
+ }
+}
+
+
+
+/**
* Clip the rectangle defined by (x, y, width, height) against the bounds
* specified by [xmin, xmax) and [ymin, ymax).
* \return GL_FALSE if rect is totally clipped, GL_TRUE otherwise.