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gecko-dev/gfx/gl/GLReadTexImageHelper.cpp

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23 KiB
C++
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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* vim: set ts=8 sts=4 et sw=4 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "GLReadTexImageHelper.h"
#include "GLContext.h"
#include "OGLShaderProgram.h"
#include "gfxTypes.h"
#include "gfxContext.h"
#include "gfxImageSurface.h"
#include "ScopedGLHelpers.h"
#include "mozilla/gfx/2D.h"
#include "gfx2DGlue.h"
namespace mozilla {
namespace gl {
using namespace mozilla::gfx;
GLReadTexImageHelper::GLReadTexImageHelper(GLContext* gl)
: mGL(gl)
{
mPrograms[0] = 0;
mPrograms[1] = 0;
mPrograms[2] = 0;
mPrograms[3] = 0;
}
GLReadTexImageHelper::~GLReadTexImageHelper()
{
mGL->fDeleteProgram(mPrograms[0]);
mGL->fDeleteProgram(mPrograms[1]);
mGL->fDeleteProgram(mPrograms[2]);
mGL->fDeleteProgram(mPrograms[3]);
}
static const GLchar
readTextureImageVS[] =
"attribute vec2 aVertex;\n"
"attribute vec2 aTexCoord;\n"
"varying vec2 vTexCoord;\n"
"void main() { gl_Position = vec4(aVertex, 0, 1); vTexCoord = aTexCoord; }";
static const GLchar
readTextureImageFS_TEXTURE_2D[] =
"#ifdef GL_ES\n"
"precision mediump float;\n"
"#endif\n"
"varying vec2 vTexCoord;\n"
"uniform sampler2D uTexture;\n"
"void main() { gl_FragColor = texture2D(uTexture, vTexCoord); }";
static const GLchar
readTextureImageFS_TEXTURE_2D_BGRA[] =
"#ifdef GL_ES\n"
"precision mediump float;\n"
"#endif\n"
"varying vec2 vTexCoord;\n"
"uniform sampler2D uTexture;\n"
"void main() { gl_FragColor = texture2D(uTexture, vTexCoord).bgra; }";
static const GLchar
readTextureImageFS_TEXTURE_EXTERNAL[] =
"#extension GL_OES_EGL_image_external : require\n"
"#ifdef GL_ES\n"
"precision mediump float;\n"
"#endif\n"
"varying vec2 vTexCoord;\n"
"uniform samplerExternalOES uTexture;\n"
"void main() { gl_FragColor = texture2D(uTexture, vTexCoord); }";
static const GLchar
readTextureImageFS_TEXTURE_RECTANGLE[] =
"#extension GL_ARB_texture_rectangle\n"
"#ifdef GL_ES\n"
"precision mediump float;\n"
"#endif\n"
"varying vec2 vTexCoord;\n"
"uniform sampler2DRect uTexture;\n"
"void main() { gl_FragColor = texture2DRect(uTexture, vTexCoord).bgra; }";
GLuint
GLReadTexImageHelper::TextureImageProgramFor(GLenum aTextureTarget, int aConfig) {
int variant = 0;
const GLchar* readTextureImageFS = nullptr;
if (aTextureTarget == LOCAL_GL_TEXTURE_2D)
{
if (aConfig & mozilla::layers::ENABLE_TEXTURE_RB_SWAP)
{ // Need to swizzle R/B.
readTextureImageFS = readTextureImageFS_TEXTURE_2D_BGRA;
variant = 1;
}
else
{
readTextureImageFS = readTextureImageFS_TEXTURE_2D;
variant = 0;
}
} else if (aTextureTarget == LOCAL_GL_TEXTURE_EXTERNAL) {
readTextureImageFS = readTextureImageFS_TEXTURE_EXTERNAL;
variant = 2;
} else if (aTextureTarget == LOCAL_GL_TEXTURE_RECTANGLE) {
readTextureImageFS = readTextureImageFS_TEXTURE_RECTANGLE;
variant = 3;
}
/* This might be overkill, but assure that we don't access out-of-bounds */
MOZ_ASSERT((size_t) variant < ArrayLength(mPrograms));
if (!mPrograms[variant]) {
GLuint vs = mGL->fCreateShader(LOCAL_GL_VERTEX_SHADER);
const GLchar* vsSourcePtr = &readTextureImageVS[0];
mGL->fShaderSource(vs, 1, &vsSourcePtr, nullptr);
mGL->fCompileShader(vs);
GLuint fs = mGL->fCreateShader(LOCAL_GL_FRAGMENT_SHADER);
mGL->fShaderSource(fs, 1, &readTextureImageFS, nullptr);
mGL->fCompileShader(fs);
GLuint program = mGL->fCreateProgram();
mGL->fAttachShader(program, vs);
mGL->fAttachShader(program, fs);
mGL->fBindAttribLocation(program, 0, "aVertex");
mGL->fBindAttribLocation(program, 1, "aTexCoord");
mGL->fLinkProgram(program);
GLint success;
mGL->fGetProgramiv(program, LOCAL_GL_LINK_STATUS, &success);
if (!success) {
mGL->fDeleteProgram(program);
program = 0;
}
mGL->fDeleteShader(vs);
mGL->fDeleteShader(fs);
mPrograms[variant] = program;
}
return mPrograms[variant];
}
bool
GLReadTexImageHelper::DidGLErrorOccur(const char* str)
{
GLenum error = mGL->fGetError();
if (error != LOCAL_GL_NO_ERROR) {
printf_stderr("GL ERROR: %s (0x%04x) %s\n",
mGL->GLErrorToString(error), error, str);
return true;
}
return false;
}
static bool
GetActualReadFormats(GLContext* gl,
GLenum destFormat, GLenum destType,
GLenum& readFormat, GLenum& readType)
{
if (destFormat == LOCAL_GL_RGBA &&
destType == LOCAL_GL_UNSIGNED_BYTE)
{
readFormat = destFormat;
readType = destType;
return true;
}
bool fallback = true;
if (gl->IsGLES()) {
GLenum auxFormat = 0;
GLenum auxType = 0;
gl->fGetIntegerv(LOCAL_GL_IMPLEMENTATION_COLOR_READ_FORMAT, (GLint*)&auxFormat);
gl->fGetIntegerv(LOCAL_GL_IMPLEMENTATION_COLOR_READ_TYPE, (GLint*)&auxType);
if (destFormat == auxFormat &&
destType == auxType)
{
fallback = false;
}
} else {
switch (destFormat) {
case LOCAL_GL_RGB: {
if (destType == LOCAL_GL_UNSIGNED_SHORT_5_6_5_REV)
fallback = false;
break;
}
case LOCAL_GL_BGRA: {
if (destType == LOCAL_GL_UNSIGNED_INT_8_8_8_8_REV)
fallback = false;
break;
}
}
}
if (fallback) {
readFormat = LOCAL_GL_RGBA;
readType = LOCAL_GL_UNSIGNED_BYTE;
return false;
} else {
readFormat = destFormat;
readType = destType;
return true;
}
}
static void SwapRAndBComponents(DataSourceSurface* surf)
{
uint8_t *row = surf->GetData();
if (!row) {
MOZ_ASSERT(false, "SwapRAndBComponents: Failed to get data from DataSourceSurface.");
return;
}
size_t rowBytes = surf->GetSize().width*4;
size_t rowHole = surf->Stride() - rowBytes;
size_t rows = surf->GetSize().height;
while (rows) {
const uint8_t *rowEnd = row + rowBytes;
while (row != rowEnd) {
row[0] ^= row[2];
row[2] ^= row[0];
row[0] ^= row[2];
row += 4;
}
row += rowHole;
--rows;
}
}
static uint16_t PackRGB565(uint8_t r, uint8_t g, uint8_t b)
{
uint16_t pixel = ((r << 11) & 0xf800) |
((g << 5) & 0x07e0) |
((b ) & 0x001f);
return pixel;
}
static void CopyDataSourceSurface(DataSourceSurface* aSource,
DataSourceSurface* aDest)
{
MOZ_ASSERT(aSource->GetSize() == aDest->GetSize());
MOZ_ASSERT(aSource->GetFormat() == SurfaceFormat::B8G8R8A8 ||
aSource->GetFormat() == SurfaceFormat::B8G8R8X8);
uint8_t *srcRow = aSource->GetData();
size_t srcRowBytes = aSource->GetSize().width * BytesPerPixel(aSource->GetFormat());
size_t srcRowHole = aSource->Stride() - srcRowBytes;
uint8_t *destRow = aDest->GetData();
size_t destRowBytes = aDest->GetSize().width * BytesPerPixel(aDest->GetFormat());
size_t destRowHole = aDest->Stride() - destRowBytes;
bool needsRBSwap = false;
if (aDest->GetFormat() == SurfaceFormat::B8G8R8A8 ||
aDest->GetFormat() == SurfaceFormat::B8G8R8X8) {
needsRBSwap = true;
}
bool needsConvertTo16Bits = false;
if (aDest->GetFormat() == SurfaceFormat::R5G6B5) {
needsConvertTo16Bits = true;
}
size_t rows = aSource->GetSize().height;
while (rows) {
const uint8_t *srcRowEnd = srcRow + srcRowBytes;
while (srcRow != srcRowEnd) {
uint8_t r = needsRBSwap ? srcRow[2] : srcRow[0];
uint8_t g = srcRow[1];
uint8_t b = needsRBSwap ? srcRow[0] : srcRow[2];
uint8_t a = srcRow[3];
if (needsConvertTo16Bits) {
*(uint16_t*)destRow = PackRGB565(r, g, b);
} else {
destRow[0] = r;
destRow[1] = g;
destRow[2] = b;
destRow[3] = a;
}
srcRow += BytesPerPixel(aSource->GetFormat());
destRow += BytesPerPixel(aDest->GetFormat());
}
srcRow += srcRowHole;
destRow += destRowHole;
--rows;
}
}
static int
CalcRowStride(int width, int pixelSize, int alignment)
{
MOZ_ASSERT(alignment);
int rowStride = width * pixelSize;
if (rowStride % alignment) { // Extra at the end of the line?
int alignmentCount = rowStride / alignment;
rowStride = (alignmentCount+1) * alignment;
}
return rowStride;
}
static int
GuessAlignment(int width, int pixelSize, int rowStride)
{
int alignment = 8; // Max GLES allows.
while (CalcRowStride(width, pixelSize, alignment) != rowStride) {
alignment /= 2;
if (!alignment) {
NS_WARNING("Bad alignment for GLES. Will use temp surf for readback.");
return 0;
}
}
return alignment;
}
void
ReadPixelsIntoDataSurface(GLContext* gl, DataSourceSurface* dest) {
gl->MakeCurrent();
MOZ_ASSERT(dest->GetSize().width != 0);
MOZ_ASSERT(dest->GetSize().height != 0);
bool hasAlpha = dest->GetFormat() == SurfaceFormat::B8G8R8A8 ||
dest->GetFormat() == SurfaceFormat::R8G8B8A8;
int destPixelSize;
GLenum destFormat;
GLenum destType;
switch (dest->GetFormat()) {
case SurfaceFormat::B8G8R8A8:
case SurfaceFormat::B8G8R8X8:
// Needs host (little) endian ARGB.
destFormat = LOCAL_GL_BGRA;
destType = LOCAL_GL_UNSIGNED_INT_8_8_8_8_REV;
break;
case SurfaceFormat::R8G8B8A8:
case SurfaceFormat::R8G8B8X8:
// Needs host (little) endian ABGR.
destFormat = LOCAL_GL_RGBA;
destType = LOCAL_GL_UNSIGNED_BYTE;
break;
case SurfaceFormat::R5G6B5:
destFormat = LOCAL_GL_RGB;
destType = LOCAL_GL_UNSIGNED_SHORT_5_6_5_REV;
break;
default:
MOZ_CRASH("Bad format.");
}
destPixelSize = BytesPerPixel(dest->GetFormat());
MOZ_ASSERT(dest->GetSize().width * destPixelSize <= dest->Stride());
GLenum readFormat = destFormat;
GLenum readType = destType;
bool needsTempSurf = !GetActualReadFormats(gl,
destFormat, destType,
readFormat, readType);
RefPtr<DataSourceSurface> tempSurf;
DataSourceSurface* readSurf = dest;
int readAlignment = GuessAlignment(dest->GetSize().width,
destPixelSize,
dest->Stride());
if (!readAlignment) {
needsTempSurf = true;
}
if (needsTempSurf) {
if (gl->DebugMode()) {
NS_WARNING("Needing intermediary surface for ReadPixels. This will be slow!");
}
SurfaceFormat readFormatGFX;
switch (readFormat) {
case LOCAL_GL_RGBA:
case LOCAL_GL_BGRA: {
readFormatGFX = hasAlpha ? SurfaceFormat::B8G8R8A8
: SurfaceFormat::B8G8R8X8;
break;
}
case LOCAL_GL_RGB: {
MOZ_ASSERT(destPixelSize == 2);
MOZ_ASSERT(readType == LOCAL_GL_UNSIGNED_SHORT_5_6_5_REV);
readFormatGFX = SurfaceFormat::R5G6B5;
break;
}
default: {
MOZ_CRASH("Bad read format.");
}
}
switch (readType) {
case LOCAL_GL_UNSIGNED_BYTE: {
MOZ_ASSERT(readFormat == LOCAL_GL_RGBA);
readAlignment = 1;
break;
}
case LOCAL_GL_UNSIGNED_INT_8_8_8_8_REV: {
MOZ_ASSERT(readFormat == LOCAL_GL_BGRA);
readAlignment = 4;
break;
}
case LOCAL_GL_UNSIGNED_SHORT_5_6_5_REV: {
MOZ_ASSERT(readFormat == LOCAL_GL_RGB);
readAlignment = 2;
break;
}
default: {
MOZ_CRASH("Bad read type.");
}
}
int32_t stride = dest->GetSize().width * BytesPerPixel(readFormatGFX);
tempSurf = Factory::CreateDataSourceSurfaceWithStride(dest->GetSize(),
readFormatGFX,
stride);
readSurf = tempSurf;
}
MOZ_ASSERT(readAlignment);
MOZ_ASSERT(reinterpret_cast<uintptr_t>(readSurf->GetData()) % readAlignment == 0);
GLint currentPackAlignment = 0;
gl->fGetIntegerv(LOCAL_GL_PACK_ALIGNMENT, &currentPackAlignment);
if (currentPackAlignment != readAlignment)
gl->fPixelStorei(LOCAL_GL_PACK_ALIGNMENT, readAlignment);
GLsizei width = dest->GetSize().width;
GLsizei height = dest->GetSize().height;
gl->fReadPixels(0, 0,
width, height,
readFormat, readType,
readSurf->GetData());
if (currentPackAlignment != readAlignment)
gl->fPixelStorei(LOCAL_GL_PACK_ALIGNMENT, currentPackAlignment);
if (readSurf != dest) {
MOZ_ASSERT(readFormat == LOCAL_GL_RGBA);
MOZ_ASSERT(readType == LOCAL_GL_UNSIGNED_BYTE);
CopyDataSourceSurface(readSurf, dest);
}
// Check if GL is giving back 1.0 alpha for
// RGBA reads to RGBA images from no-alpha buffers.
#ifdef XP_MACOSX
if (gl->WorkAroundDriverBugs() &&
gl->Vendor() == gl::GLVendor::NVIDIA &&
(dest->GetFormat() == SurfaceFormat::R8G8B8A8 ||
dest->GetFormat() == SurfaceFormat::B8G8R8A8) &&
width && height)
{
GLint alphaBits = 0;
gl->fGetIntegerv(LOCAL_GL_ALPHA_BITS, &alphaBits);
if (!alphaBits) {
const uint32_t alphaMask = gfxPackedPixelNoPreMultiply(0xff,0,0,0);
MOZ_ASSERT(dest->GetSize().width * destPixelSize == dest->Stride());
uint32_t* itr = (uint32_t*)dest->GetData();
uint32_t testPixel = *itr;
if ((testPixel & alphaMask) != alphaMask) {
// We need to set the alpha channel to 1.0 manually.
uint32_t* itrEnd = itr + width*height; // Stride is guaranteed to be width*4.
for (; itr != itrEnd; itr++) {
*itr |= alphaMask;
}
}
}
}
#endif
}
static TemporaryRef<DataSourceSurface> YInvertImageSurface(DataSourceSurface* aSurf)
{
RefPtr<DataSourceSurface> temp =
Factory::CreateDataSourceSurfaceWithStride(aSurf->GetSize(),
aSurf->GetFormat(),
aSurf->Stride());
RefPtr<DrawTarget> dt =
Factory::CreateDrawTargetForData(BackendType::CAIRO,
temp->GetData(),
temp->GetSize(),
temp->Stride(),
temp->GetFormat());
nsRefPtr<gfxContext> ctx = new gfxContext(dt);
ctx->SetOperator(gfxContext::OPERATOR_SOURCE);
ctx->Scale(1.0, -1.0);
ctx->Translate(-gfxPoint(0.0, aSurf->GetSize().height));
nsRefPtr<gfxImageSurface> thebesSurf =
new gfxImageSurface(aSurf->GetData(),
ThebesIntSize(aSurf->GetSize()),
aSurf->Stride(),
SurfaceFormatToImageFormat(aSurf->GetFormat()));
ctx->SetSource(thebesSurf);
ctx->Paint();
return temp.forget();
}
TemporaryRef<DataSourceSurface>
ReadBackSurface(GLContext* gl, GLuint aTexture, bool aYInvert, SurfaceFormat aFormat)
{
gl->MakeCurrent();
gl->GuaranteeResolve();
gl->fActiveTexture(LOCAL_GL_TEXTURE0);
gl->fBindTexture(LOCAL_GL_TEXTURE_2D, aTexture);
IntSize size;
gl->fGetTexLevelParameteriv(LOCAL_GL_TEXTURE_2D, 0, LOCAL_GL_TEXTURE_WIDTH, &size.width);
gl->fGetTexLevelParameteriv(LOCAL_GL_TEXTURE_2D, 0, LOCAL_GL_TEXTURE_HEIGHT, &size.height);
RefPtr<DataSourceSurface> surf =
Factory::CreateDataSourceSurfaceWithStride(size, SurfaceFormat::B8G8R8A8,
GetAlignedStride<4>(size.width * BytesPerPixel(SurfaceFormat::B8G8R8A8)));
if (!surf) {
return nullptr;
}
uint32_t currentPackAlignment = 0;
gl->fGetIntegerv(LOCAL_GL_PACK_ALIGNMENT, (GLint*)&currentPackAlignment);
if (currentPackAlignment != 4) {
gl->fPixelStorei(LOCAL_GL_PACK_ALIGNMENT, 4);
}
gl->fGetTexImage(LOCAL_GL_TEXTURE_2D, 0, LOCAL_GL_RGBA, LOCAL_GL_UNSIGNED_BYTE, surf->GetData());
if (currentPackAlignment != 4) {
gl->fPixelStorei(LOCAL_GL_PACK_ALIGNMENT, currentPackAlignment);
}
if (aFormat == SurfaceFormat::R8G8B8A8 || aFormat == SurfaceFormat::R8G8B8X8) {
SwapRAndBComponents(surf);
}
if (aYInvert) {
surf = YInvertImageSurface(surf);
}
return surf.forget();
}
#define CLEANUP_IF_GLERROR_OCCURRED(x) \
if (DidGLErrorOccur(x)) { \
isurf = nullptr; \
break; \
}
TemporaryRef<DataSourceSurface>
GLReadTexImageHelper::ReadTexImage(GLuint aTextureId,
GLenum aTextureTarget,
const gfx::IntSize& aSize,
/* ShaderConfigOGL.mFeature */ int aConfig,
bool aYInvert)
{
MOZ_ASSERT(aTextureTarget == LOCAL_GL_TEXTURE_2D ||
aTextureTarget == LOCAL_GL_TEXTURE_EXTERNAL ||
aTextureTarget == LOCAL_GL_TEXTURE_RECTANGLE_ARB);
mGL->MakeCurrent();
/* Allocate resulting image surface */
int32_t stride = aSize.width * BytesPerPixel(SurfaceFormat::R8G8B8A8);
RefPtr<DataSourceSurface> isurf =
Factory::CreateDataSourceSurfaceWithStride(aSize,
SurfaceFormat::R8G8B8A8,
stride);
GLint oldrb, oldfb, oldprog, oldTexUnit, oldTex;
GLuint rb, fb;
do {
mGL->fGetIntegerv(LOCAL_GL_RENDERBUFFER_BINDING, &oldrb);
mGL->fGetIntegerv(LOCAL_GL_FRAMEBUFFER_BINDING, &oldfb);
mGL->fGetIntegerv(LOCAL_GL_CURRENT_PROGRAM, &oldprog);
mGL->fGetIntegerv(LOCAL_GL_ACTIVE_TEXTURE, &oldTexUnit);
mGL->fActiveTexture(LOCAL_GL_TEXTURE0);
switch (aTextureTarget) {
case LOCAL_GL_TEXTURE_2D:
mGL->fGetIntegerv(LOCAL_GL_TEXTURE_BINDING_2D, &oldTex);
break;
case LOCAL_GL_TEXTURE_EXTERNAL:
mGL->fGetIntegerv(LOCAL_GL_TEXTURE_BINDING_EXTERNAL, &oldTex);
break;
case LOCAL_GL_TEXTURE_RECTANGLE:
mGL->fGetIntegerv(LOCAL_GL_TEXTURE_BINDING_RECTANGLE, &oldTex);
break;
default: /* Already checked above */
break;
}
ScopedGLState scopedScissorTestState(mGL, LOCAL_GL_SCISSOR_TEST, false);
ScopedGLState scopedBlendState(mGL, LOCAL_GL_BLEND, false);
ScopedViewportRect scopedViewportRect(mGL, 0, 0, aSize.width, aSize.height);
/* Setup renderbuffer */
mGL->fGenRenderbuffers(1, &rb);
mGL->fBindRenderbuffer(LOCAL_GL_RENDERBUFFER, rb);
GLenum rbInternalFormat =
mGL->IsGLES()
? (mGL->IsExtensionSupported(GLContext::OES_rgb8_rgba8) ? LOCAL_GL_RGBA8 : LOCAL_GL_RGBA4)
: LOCAL_GL_RGBA;
mGL->fRenderbufferStorage(LOCAL_GL_RENDERBUFFER, rbInternalFormat, aSize.width, aSize.height);
CLEANUP_IF_GLERROR_OCCURRED("when binding and creating renderbuffer");
/* Setup framebuffer */
mGL->fGenFramebuffers(1, &fb);
mGL->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, fb);
mGL->fFramebufferRenderbuffer(LOCAL_GL_FRAMEBUFFER, LOCAL_GL_COLOR_ATTACHMENT0,
LOCAL_GL_RENDERBUFFER, rb);
CLEANUP_IF_GLERROR_OCCURRED("when binding and creating framebuffer");
MOZ_ASSERT(mGL->fCheckFramebufferStatus(LOCAL_GL_FRAMEBUFFER) == LOCAL_GL_FRAMEBUFFER_COMPLETE);
/* Setup vertex and fragment shader */
GLuint program = TextureImageProgramFor(aTextureTarget, aConfig);
MOZ_ASSERT(program);
mGL->fUseProgram(program);
CLEANUP_IF_GLERROR_OCCURRED("when using program");
mGL->fUniform1i(mGL->fGetUniformLocation(program, "uTexture"), 0);
CLEANUP_IF_GLERROR_OCCURRED("when setting uniform location");
/* Setup quad geometry */
mGL->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, 0);
float w = (aTextureTarget == LOCAL_GL_TEXTURE_RECTANGLE) ? (float) aSize.width : 1.0f;
float h = (aTextureTarget == LOCAL_GL_TEXTURE_RECTANGLE) ? (float) aSize.height : 1.0f;
const float
vertexArray[4*2] = {
-1.0f, -1.0f,
1.0f, -1.0f,
-1.0f, 1.0f,
1.0f, 1.0f
};
ScopedVertexAttribPointer autoAttrib0(mGL, 0, 2, LOCAL_GL_FLOAT, LOCAL_GL_FALSE, 0, 0, vertexArray);
const float u0 = 0.0f;
const float u1 = w;
const float v0 = aYInvert ? h : 0.0f;
const float v1 = aYInvert ? 0.0f : h;
const float texCoordArray[8] = { u0, v0,
u1, v0,
u0, v1,
u1, v1 };
ScopedVertexAttribPointer autoAttrib1(mGL, 1, 2, LOCAL_GL_FLOAT, LOCAL_GL_FALSE, 0, 0, texCoordArray);
/* Bind the texture */
if (aTextureId) {
mGL->fBindTexture(aTextureTarget, aTextureId);
CLEANUP_IF_GLERROR_OCCURRED("when binding texture");
}
/* Draw quad */
mGL->fClearColor(1.0f, 0.0f, 1.0f, 1.0f);
mGL->fClear(LOCAL_GL_COLOR_BUFFER_BIT);
CLEANUP_IF_GLERROR_OCCURRED("when clearing color buffer");
mGL->fDrawArrays(LOCAL_GL_TRIANGLE_STRIP, 0, 4);
CLEANUP_IF_GLERROR_OCCURRED("when drawing texture");
/* Read-back draw results */
ReadPixelsIntoDataSurface(mGL, isurf);
CLEANUP_IF_GLERROR_OCCURRED("when reading pixels into surface");
} while (false);
/* Restore GL state */
mGL->fBindRenderbuffer(LOCAL_GL_RENDERBUFFER, oldrb);
mGL->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, oldfb);
mGL->fUseProgram(oldprog);
// note that deleting 0 has no effect in any of these calls
mGL->fDeleteRenderbuffers(1, &rb);
mGL->fDeleteFramebuffers(1, &fb);
if (aTextureId)
mGL->fBindTexture(aTextureTarget, oldTex);
if (oldTexUnit != LOCAL_GL_TEXTURE0)
mGL->fActiveTexture(oldTexUnit);
return isurf.forget();
}
#undef CLEANUP_IF_GLERROR_OCCURRED
}
}
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