already_AddRefed<gfx::DrawTarget>
PersistentBufferProviderShared::BorrowDrawTarget(const gfx::IntRect& aPersistedRect)
{
if (!mFwd->GetTextureForwarder()->IPCOpen()) {
return nullptr;
}
MOZ_ASSERT(!mSnapshot);
if (IsActivityTracked()) {
mFwd->GetActiveResourceTracker().MarkUsed(this);
} else {
mFwd->GetActiveResourceTracker().AddObject(this);
}
if (mDrawTarget) {
RefPtr<gfx::DrawTarget> dt(mDrawTarget);
return dt.forget();
}
mFront = Nothing();
auto previousBackBuffer = mBack;
TextureClient* tex = GetTexture(mBack);
// First try to reuse the current back buffer. If we can do that it means
// we can skip copying its content to the new back buffer.
if (tex && tex->IsReadLocked()) {
// The back buffer is currently used by the compositor, we can't draw
// into it.
tex = nullptr;
}
if (!tex) {
// Try to grab an already allocated texture if any is available.
for (uint32_t i = 0; i < mTextures.length(); ++i) {
if (!mTextures[i]->IsReadLocked()) {
mBack = Some(i);
tex = mTextures[i];
break;
}
}
}
if (!tex) {
// We have to allocate a new texture.
if (mTextures.length() >= 4) {
// We should never need to buffer that many textures, something's wrong.
MOZ_ASSERT(false);
// In theory we throttle the main thread when the compositor can't keep up,
// so we shoud never get in a situation where we sent 4 textures to the
// compositor and the latter as not released any of them.
// This seems to happen, however, in some edge cases such as just after a
// device reset (cf. Bug 1291163).
// It would be pretty bad to keep piling textures up at this point so we
// call NotifyInactive to remove some of our textures.
NotifyInactive();
// Give up now. The caller can fall-back to a non-shared buffer provider.
return nullptr;
}
RefPtr<TextureClient> newTexture = TextureClient::CreateForDrawing(
mFwd, mFormat, mSize,
BackendSelector::Canvas,
TextureFlags::DEFAULT,
TextureAllocationFlags::ALLOC_DEFAULT
);
MOZ_ASSERT(newTexture);
if (newTexture) {
if (mTextures.append(newTexture)) {
tex = newTexture;
mBack = Some<uint32_t>(mTextures.length() - 1);
}
}
}
if (!tex || !tex->Lock(OpenMode::OPEN_READ_WRITE)) {
return nullptr;
}
if (mBack != previousBackBuffer && !aPersistedRect.IsEmpty()) {
TextureClient* previous = GetTexture(previousBackBuffer);
if (previous && previous->Lock(OpenMode::OPEN_READ)) {
DebugOnly<bool> success = previous->CopyToTextureClient(tex, &aPersistedRect, nullptr);
MOZ_ASSERT(success);
previous->Unlock();
}
}
mDrawTarget = tex->BorrowDrawTarget();
RefPtr<gfx::DrawTarget> dt(mDrawTarget);
return dt.forget();
}
void
GLBlitTextureImageHelper::BlitTextureImage(TextureImage *aSrc, const gfx::IntRect& aSrcRect,
TextureImage *aDst, const gfx::IntRect& aDstRect)
{
GLContext *gl = mCompositor->gl();
if (!aSrc || !aDst || aSrcRect.IsEmpty() || aDstRect.IsEmpty())
return;
int savedFb = 0;
gl->fGetIntegerv(LOCAL_GL_FRAMEBUFFER_BINDING, &savedFb);
ScopedGLState scopedScissorTestState(gl, LOCAL_GL_SCISSOR_TEST, false);
ScopedGLState scopedBlendState(gl, 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
gfx::IntRect dstSubRect;
gfx::IntRect dstTextureRect = 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...
gfx::IntRect 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
gfx::IntRect srcSubRect;
gfx::IntRect srcTextureRect = 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 (*)
gfx::IntRect 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
gfx::IntSize srcSize = srcTextureRect.Size();
gfx::IntSize 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(gl, 0, 0, dstSize.width, dstSize.height);
RectTriangles rects;
gfx::IntSize realTexSize = srcSize;
if (!CanUploadNonPowerOfTwo(gl)) {
realTexSize = gfx::IntSize(RoundUpPow2(srcSize.width),
RoundUpPow2(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(gl, LOCAL_GL_TEXTURE0);
ScopedBindTexture autoTex(gl, aSrc->GetTextureID());
ScopedVertexAttribPointer autoAttrib0(gl, 0, 2, LOCAL_GL_FLOAT, LOCAL_GL_FALSE, 0, 0, rects.vertCoords().Elements());
ScopedVertexAttribPointer autoAttrib1(gl, 1, 2, LOCAL_GL_FLOAT, LOCAL_GL_FALSE, 0, 0, rects.texCoords().Elements());
gl->fDrawArrays(LOCAL_GL_TRIANGLES, 0, rects.elements());
} while (aSrc->NextTile());
} while (aDst->NextTile());
// unbind the previous texture from the framebuffer
SetBlitFramebufferForDestTexture(0);
gl->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, savedFb);
}
