gecko-dev/gfx/gl/GLBlitTextureImageHelper.cpp

282 lines
11 KiB
C++

/* -*- 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 "GLBlitTextureImageHelper.h"
#include "GLUploadHelpers.h"
#include "DecomposeIntoNoRepeatTriangles.h"
#include "GLContext.h"
#include "ScopedGLHelpers.h"
#include "nsRect.h"
#include "gfx2DGlue.h"
#include "gfxUtils.h"
namespace mozilla {
namespace gl {
GLBlitTextureImageHelper::GLBlitTextureImageHelper(GLContext* gl)
: mGL(gl)
, mBlitProgram(0)
, mBlitFramebuffer(0)
{
}
GLBlitTextureImageHelper::~GLBlitTextureImageHelper()
{
// Likely used by OGL Layers.
mGL->fDeleteProgram(mBlitProgram);
mGL->fDeleteFramebuffers(1, &mBlitFramebuffer);
}
void
GLBlitTextureImageHelper::BlitTextureImage(TextureImage *aSrc, const nsIntRect& aSrcRect,
TextureImage *aDst, const nsIntRect& aDstRect)
{
NS_ASSERTION(!aSrc->InUpdate(), "Source texture is in update!");
NS_ASSERTION(!aDst->InUpdate(), "Destination texture is in update!");
if (aSrcRect.IsEmpty() || aDstRect.IsEmpty())
return;
int savedFb = 0;
mGL->fGetIntegerv(LOCAL_GL_FRAMEBUFFER_BINDING, &savedFb);
ScopedGLState scopedScissorTestState(mGL, LOCAL_GL_SCISSOR_TEST, false);
ScopedGLState scopedBlendState(mGL, LOCAL_GL_BLEND, false);
// 2.0 means scale up by two
float blitScaleX = float(aDstRect.width) / float(aSrcRect.width);
float blitScaleY = float(aDstRect.height) / float(aSrcRect.height);
// We start iterating over all destination tiles
aDst->BeginBigImageIteration();
do {
// calculate portion of the tile that is going to be painted to
nsIntRect dstSubRect;
nsIntRect dstTextureRect = ThebesIntRect(aDst->GetTileRect());
dstSubRect.IntersectRect(aDstRect, dstTextureRect);
// this tile is not part of the destination rectangle aDstRect
if (dstSubRect.IsEmpty())
continue;
// (*) transform the rect of this tile into the rectangle defined by aSrcRect...
nsIntRect dstInSrcRect(dstSubRect);
dstInSrcRect.MoveBy(-aDstRect.TopLeft());
// ...which might be of different size, hence scale accordingly
dstInSrcRect.ScaleRoundOut(1.0f / blitScaleX, 1.0f / blitScaleY);
dstInSrcRect.MoveBy(aSrcRect.TopLeft());
SetBlitFramebufferForDestTexture(aDst->GetTextureID());
UseBlitProgram();
aSrc->BeginBigImageIteration();
// now iterate over all tiles in the source Image...
do {
// calculate portion of the source tile that is in the source rect
nsIntRect srcSubRect;
nsIntRect srcTextureRect = ThebesIntRect(aSrc->GetTileRect());
srcSubRect.IntersectRect(aSrcRect, srcTextureRect);
// this tile is not part of the source rect
if (srcSubRect.IsEmpty()) {
continue;
}
// calculate intersection of source rect with destination rect
srcSubRect.IntersectRect(srcSubRect, dstInSrcRect);
// this tile does not overlap the current destination tile
if (srcSubRect.IsEmpty()) {
continue;
}
// We now have the intersection of
// the current source tile
// and the desired source rectangle
// and the destination tile
// and the desired destination rectange
// in destination space.
// We need to transform this back into destination space, inverting the transform from (*)
nsIntRect srcSubInDstRect(srcSubRect);
srcSubInDstRect.MoveBy(-aSrcRect.TopLeft());
srcSubInDstRect.ScaleRoundOut(blitScaleX, blitScaleY);
srcSubInDstRect.MoveBy(aDstRect.TopLeft());
// we transform these rectangles to be relative to the current src and dst tiles, respectively
nsIntSize srcSize = srcTextureRect.Size();
nsIntSize dstSize = dstTextureRect.Size();
srcSubRect.MoveBy(-srcTextureRect.x, -srcTextureRect.y);
srcSubInDstRect.MoveBy(-dstTextureRect.x, -dstTextureRect.y);
float dx0 = 2.0f * float(srcSubInDstRect.x) / float(dstSize.width) - 1.0f;
float dy0 = 2.0f * float(srcSubInDstRect.y) / float(dstSize.height) - 1.0f;
float dx1 = 2.0f * float(srcSubInDstRect.x + srcSubInDstRect.width) / float(dstSize.width) - 1.0f;
float dy1 = 2.0f * float(srcSubInDstRect.y + srcSubInDstRect.height) / float(dstSize.height) - 1.0f;
ScopedViewportRect autoViewportRect(mGL, 0, 0, dstSize.width, dstSize.height);
RectTriangles rects;
nsIntSize realTexSize = srcSize;
if (!CanUploadNonPowerOfTwo(mGL)) {
realTexSize = nsIntSize(gfx::NextPowerOfTwo(srcSize.width),
gfx::NextPowerOfTwo(srcSize.height));
}
if (aSrc->GetWrapMode() == LOCAL_GL_REPEAT) {
rects.addRect(/* dest rectangle */
dx0, dy0, dx1, dy1,
/* tex coords */
srcSubRect.x / float(realTexSize.width),
srcSubRect.y / float(realTexSize.height),
srcSubRect.XMost() / float(realTexSize.width),
srcSubRect.YMost() / float(realTexSize.height));
} else {
DecomposeIntoNoRepeatTriangles(srcSubRect, realTexSize, rects);
// now put the coords into the d[xy]0 .. d[xy]1 coordinate space
// from the 0..1 that it comes out of decompose
InfallibleTArray<RectTriangles::coord>& coords = rects.vertCoords();
for (unsigned int i = 0; i < coords.Length(); ++i) {
coords[i].x = (coords[i].x * (dx1 - dx0)) + dx0;
coords[i].y = (coords[i].y * (dy1 - dy0)) + dy0;
}
}
ScopedBindTextureUnit autoTexUnit(mGL, LOCAL_GL_TEXTURE0);
ScopedBindTexture autoTex(mGL, aSrc->GetTextureID());
mGL->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, 0);
mGL->fVertexAttribPointer(0, 2, LOCAL_GL_FLOAT, LOCAL_GL_FALSE, 0, rects.vertCoords().Elements());
mGL->fVertexAttribPointer(1, 2, LOCAL_GL_FLOAT, LOCAL_GL_FALSE, 0, rects.texCoords().Elements());
mGL->fEnableVertexAttribArray(0);
mGL->fEnableVertexAttribArray(1);
mGL->fDrawArrays(LOCAL_GL_TRIANGLES, 0, rects.elements());
mGL->fDisableVertexAttribArray(0);
mGL->fDisableVertexAttribArray(1);
} while (aSrc->NextTile());
} while (aDst->NextTile());
mGL->fVertexAttribPointer(0, 2, LOCAL_GL_FLOAT, LOCAL_GL_FALSE, 0, nullptr);
mGL->fVertexAttribPointer(1, 2, LOCAL_GL_FLOAT, LOCAL_GL_FALSE, 0, nullptr);
// unbind the previous texture from the framebuffer
SetBlitFramebufferForDestTexture(0);
mGL->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, savedFb);
}
void
GLBlitTextureImageHelper::SetBlitFramebufferForDestTexture(GLuint aTexture)
{
if (!mBlitFramebuffer) {
mGL->fGenFramebuffers(1, &mBlitFramebuffer);
}
mGL->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, mBlitFramebuffer);
mGL->fFramebufferTexture2D(LOCAL_GL_FRAMEBUFFER,
LOCAL_GL_COLOR_ATTACHMENT0,
LOCAL_GL_TEXTURE_2D,
aTexture,
0);
GLenum result = mGL->fCheckFramebufferStatus(LOCAL_GL_FRAMEBUFFER);
if (aTexture && (result != LOCAL_GL_FRAMEBUFFER_COMPLETE)) {
nsAutoCString msg;
msg.Append("Framebuffer not complete -- error 0x");
msg.AppendInt(result, 16);
// Note: if you are hitting this, it is likely that
// your texture is not texture complete -- that is, you
// allocated a texture name, but didn't actually define its
// size via a call to TexImage2D.
NS_RUNTIMEABORT(msg.get());
}
}
void
GLBlitTextureImageHelper::UseBlitProgram()
{
if (mBlitProgram) {
mGL->fUseProgram(mBlitProgram);
return;
}
mBlitProgram = mGL->fCreateProgram();
GLuint shaders[2];
shaders[0] = mGL->fCreateShader(LOCAL_GL_VERTEX_SHADER);
shaders[1] = mGL->fCreateShader(LOCAL_GL_FRAGMENT_SHADER);
const char *blitVSSrc =
"attribute vec2 aVertex;"
"attribute vec2 aTexCoord;"
"varying vec2 vTexCoord;"
"void main() {"
" vTexCoord = aTexCoord;"
" gl_Position = vec4(aVertex, 0.0, 1.0);"
"}";
const char *blitFSSrc = "#ifdef GL_ES\nprecision mediump float;\n#endif\n"
"uniform sampler2D uSrcTexture;"
"varying vec2 vTexCoord;"
"void main() {"
" gl_FragColor = texture2D(uSrcTexture, vTexCoord);"
"}";
mGL->fShaderSource(shaders[0], 1, (const GLchar**) &blitVSSrc, nullptr);
mGL->fShaderSource(shaders[1], 1, (const GLchar**) &blitFSSrc, nullptr);
for (int i = 0; i < 2; ++i) {
GLint success, len = 0;
mGL->fCompileShader(shaders[i]);
mGL->fGetShaderiv(shaders[i], LOCAL_GL_COMPILE_STATUS, &success);
NS_ASSERTION(success, "Shader compilation failed!");
if (!success) {
nsAutoCString log;
mGL->fGetShaderiv(shaders[i], LOCAL_GL_INFO_LOG_LENGTH, (GLint*) &len);
log.SetCapacity(len);
mGL->fGetShaderInfoLog(shaders[i], len, (GLint*) &len, (char*) log.BeginWriting());
log.SetLength(len);
printf_stderr("Shader %d compilation failed:\n%s\n", i, log.get());
return;
}
mGL->fAttachShader(mBlitProgram, shaders[i]);
mGL->fDeleteShader(shaders[i]);
}
mGL->fBindAttribLocation(mBlitProgram, 0, "aVertex");
mGL->fBindAttribLocation(mBlitProgram, 1, "aTexCoord");
mGL->fLinkProgram(mBlitProgram);
GLint success, len = 0;
mGL->fGetProgramiv(mBlitProgram, LOCAL_GL_LINK_STATUS, &success);
NS_ASSERTION(success, "Shader linking failed!");
if (!success) {
nsAutoCString log;
mGL->fGetProgramiv(mBlitProgram, LOCAL_GL_INFO_LOG_LENGTH, (GLint*) &len);
log.SetCapacity(len);
mGL->fGetProgramInfoLog(mBlitProgram, len, (GLint*) &len, (char*) log.BeginWriting());
log.SetLength(len);
printf_stderr("Program linking failed:\n%s\n", log.get());
return;
}
mGL->fUseProgram(mBlitProgram);
mGL->fUniform1i(mGL->fGetUniformLocation(mBlitProgram, "uSrcTexture"), 0);
}
}
}