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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 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
#include "GLReadTexImageHelper.h"
#include <utility>
#include "GLContext.h"
#include "OGLShaderProgram.h"
#include "ScopedGLHelpers.h"
#include "gfx2DGlue.h"
#include "gfxColor.h"
#include "gfxTypes.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/gfx/Swizzle.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() {
if (!mGL->MakeCurrent()) return;
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"
"uniform mat4 uTexMatrix;\n"
"varying vec2 vTexCoord;\n"
"void main() {\n"
" gl_Position = vec4(aVertex, 0, 1);\n"
" vTexCoord = (uTexMatrix * vec4(aTexCoord, 0.0, 1.0)).xy;\n"
"}";
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 < std::size(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 %s\n",
GLContext::GLErrorToString(error).c_str(), str);
return true;
}
return false;
}
bool GetActualReadFormats(GLContext* gl, GLenum destFormat, GLenum destType,
GLenum* out_readFormat, GLenum* out_readType) {
MOZ_ASSERT(out_readFormat);
MOZ_ASSERT(out_readType);
if (destFormat == LOCAL_GL_RGBA && destType == LOCAL_GL_UNSIGNED_BYTE) {
*out_readFormat = destFormat;
*out_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_BYTE ||
destType == LOCAL_GL_UNSIGNED_INT_8_8_8_8_REV) {
fallback = false;
}
break;
}
}
}
if (fallback) {
*out_readFormat = LOCAL_GL_RGBA;
*out_readType = LOCAL_GL_UNSIGNED_BYTE;
return false;
} else {
*out_readFormat = destFormat;
*out_readType = destType;
return true;
}
}
void SwapRAndBComponents(DataSourceSurface* surf) {
DataSourceSurface::MappedSurface map;
if (!surf->Map(DataSourceSurface::MapType::READ_WRITE, &map)) {
MOZ_ASSERT(false, "SwapRAndBComponents: Failed to map surface.");
return;
}
MOZ_ASSERT(map.mStride >= 0);
const size_t rowBytes = surf->GetSize().width * 4;
const size_t rowHole = map.mStride - rowBytes;
uint8_t* row = map.mData;
if (!row) {
MOZ_ASSERT(false,
"SwapRAndBComponents: Failed to get data from"
" DataSourceSurface.");
surf->Unmap();
return;
}
const size_t rows = surf->GetSize().height;
for (size_t i = 0; i < rows; i++) {
const uint8_t* rowEnd = row + rowBytes;
while (row != rowEnd) {
std::swap(row[0], row[2]);
row += 4;
}
row += rowHole;
}
surf->Unmap();
}
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 ReadPixelsIntoBuffer(GLContext* gl, uint8_t* aData, int32_t aStride,
const IntSize& aSize, SurfaceFormat aFormat) {
gl->MakeCurrent();
MOZ_ASSERT(aSize.width != 0);
MOZ_ASSERT(aSize.height != 0);
bool hasAlpha =
aFormat == SurfaceFormat::B8G8R8A8 || aFormat == SurfaceFormat::R8G8B8A8;
int destPixelSize;
GLenum destFormat;
GLenum destType;
switch (aFormat) {
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_UINT16:
destFormat = LOCAL_GL_RGB;
destType = LOCAL_GL_UNSIGNED_SHORT_5_6_5_REV;
break;
default:
MOZ_CRASH("GFX: Bad format, read pixels.");
}
destPixelSize = BytesPerPixel(aFormat);
MOZ_ASSERT(aSize.width * destPixelSize <= aStride);
GLenum readFormat = destFormat;
GLenum readType = destType;
bool needsTempSurf =
!GetActualReadFormats(gl, destFormat, destType, &readFormat, &readType);
RefPtr<DataSourceSurface> tempSurf;
Maybe<DataSourceSurface::ScopedMap> tempMap;
uint8_t* data = aData;
SurfaceFormat readFormatGFX;
int readAlignment = GuessAlignment(aSize.width, destPixelSize, aStride);
if (!readAlignment) {
needsTempSurf = true;
}
if (needsTempSurf) {
if (GLContext::ShouldSpew()) {
NS_WARNING(
"Needing intermediary surface for ReadPixels. This will be slow!");
}
switch (readFormat) {
case LOCAL_GL_RGBA: {
readFormatGFX =
hasAlpha ? SurfaceFormat::R8G8B8A8 : SurfaceFormat::R8G8B8X8;
break;
}
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_UINT16;
break;
}
default: {
MOZ_CRASH("GFX: Bad read format, 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("GFX: Bad read type, read type.");
}
}
int32_t stride = aSize.width * BytesPerPixel(readFormatGFX);
tempSurf = Factory::CreateDataSourceSurfaceWithStride(aSize, readFormatGFX,
stride);
if (NS_WARN_IF(!tempSurf)) {
return;
}
tempMap.emplace(tempSurf, DataSourceSurface::READ_WRITE);
if (NS_WARN_IF(!tempMap->IsMapped())) {
return;
}
data = tempMap->GetData();
}
MOZ_ASSERT(readAlignment);
MOZ_ASSERT(reinterpret_cast<uintptr_t>(data) % readAlignment == 0);
GLsizei width = aSize.width;
GLsizei height = aSize.height;
{
ScopedPackState safePackState(gl);
gl->fPixelStorei(LOCAL_GL_PACK_ALIGNMENT, readAlignment);
gl->fReadPixels(0, 0, width, height, readFormat, readType, data);
}
if (tempMap) {
SwizzleData(tempMap->GetData(), tempMap->GetStride(), readFormatGFX, aData,
aStride, aFormat, aSize);
}
}
void ReadPixelsIntoDataSurface(GLContext* gl, DataSourceSurface* dest) {
gl->MakeCurrent();
DataSourceSurface::ScopedMap map(dest, DataSourceSurface::WRITE);
ReadPixelsIntoBuffer(gl, map.GetData(), map.GetStride(), dest->GetSize(),
dest->GetFormat());
}
already_AddRefed<gfx::DataSourceSurface> YInvertImageSurface(
gfx::DataSourceSurface* aSurf, uint32_t aStride) {
RefPtr<DataSourceSurface> temp = Factory::CreateDataSourceSurfaceWithStride(
aSurf->GetSize(), aSurf->GetFormat(), aStride);
if (NS_WARN_IF(!temp)) {
return nullptr;
}
DataSourceSurface::MappedSurface map;
if (!temp->Map(DataSourceSurface::MapType::WRITE, &map)) {
return nullptr;
}
RefPtr<DrawTarget> dt = Factory::CreateDrawTargetForData(
BackendType::CAIRO, map.mData, temp->GetSize(), map.mStride,
temp->GetFormat());
if (!dt) {
temp->Unmap();
return nullptr;
}
dt->SetTransform(Matrix::Scaling(1.0, -1.0) *
Matrix::Translation(0.0, aSurf->GetSize().height));
Rect rect(0, 0, aSurf->GetSize().width, aSurf->GetSize().height);
dt->DrawSurface(
aSurf, rect, rect, DrawSurfaceOptions(),
DrawOptions(1.0, CompositionOp::OP_SOURCE, AntialiasMode::NONE));
temp->Unmap();
return temp.forget();
}
already_AddRefed<DataSourceSurface> ReadBackSurface(GLContext* gl,
GLuint aTexture,
bool aYInvert,
SurfaceFormat aFormat) {
gl->MakeCurrent();
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 (NS_WARN_IF(!surf)) {
return nullptr;
}
uint32_t currentPackAlignment = 0;
gl->fGetIntegerv(LOCAL_GL_PACK_ALIGNMENT, (GLint*)¤tPackAlignment);
if (currentPackAlignment != 4) {
gl->fPixelStorei(LOCAL_GL_PACK_ALIGNMENT, 4);
}
DataSourceSurface::ScopedMap map(surf, DataSourceSurface::READ);
gl->fGetTexImage(LOCAL_GL_TEXTURE_2D, 0, LOCAL_GL_RGBA,
LOCAL_GL_UNSIGNED_BYTE, map.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, map.GetStride());
}
return surf.forget();
}
#define CLEANUP_IF_GLERROR_OCCURRED(x) \
if (DidGLErrorOccur(x)) { \
return false; \
}
already_AddRefed<DataSourceSurface> GLReadTexImageHelper::ReadTexImage(
GLuint aTextureId, GLenum aTextureTarget, const gfx::IntSize& aSize,
const gfx::Matrix4x4& aTexMatrix,
/* ShaderConfigOGL.mFeature */ int aConfig, bool aYInvert) {
/* Allocate resulting image surface */
int32_t stride = aSize.width * BytesPerPixel(SurfaceFormat::R8G8B8A8);
RefPtr<DataSourceSurface> isurf = Factory::CreateDataSourceSurfaceWithStride(
aSize, SurfaceFormat::R8G8B8A8, stride);
if (NS_WARN_IF(!isurf)) {
return nullptr;
}
if (!ReadTexImage(isurf, aTextureId, aTextureTarget, aSize, aTexMatrix,
aConfig, aYInvert)) {
return nullptr;
}
return isurf.forget();
}
bool GLReadTexImageHelper::ReadTexImage(
DataSourceSurface* aDest, GLuint aTextureId, GLenum aTextureTarget,
const gfx::IntSize& aSize, const gfx::Matrix4x4& aTexMatrix,
/* 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();
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 uTexture");
mGL->fUniformMatrix4fv(mGL->fGetUniformLocation(program, "uTexMatrix"), 1,
false, aTexMatrix.components);
CLEANUP_IF_GLERROR_OCCURRED("when setting uniform uTexMatrix");
/* 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");
}
mGL->fDrawArrays(LOCAL_GL_TRIANGLE_STRIP, 0, 4);
CLEANUP_IF_GLERROR_OCCURRED("when drawing texture");
/* Read-back draw results */
ReadPixelsIntoDataSurface(mGL, aDest);
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 true;
}
#undef CLEANUP_IF_GLERROR_OCCURRED
} // namespace gl
} // namespace mozilla