gecko/gfx/layers/ReadbackProcessor.cpp
2012-05-21 12:12:37 +01:00

167 lines
5.5 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* 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 "ReadbackProcessor.h"
namespace mozilla {
namespace layers {
void
ReadbackProcessor::BuildUpdates(ContainerLayer* aContainer)
{
NS_ASSERTION(mAllUpdates.IsEmpty(), "Some updates not processed?");
if (!aContainer->mMayHaveReadbackChild)
return;
aContainer->mMayHaveReadbackChild = false;
// go backwards so the updates read from earlier layers are later in the
// array.
for (Layer* l = aContainer->GetLastChild(); l; l = l->GetPrevSibling()) {
if (l->GetType() == Layer::TYPE_READBACK) {
aContainer->mMayHaveReadbackChild = true;
BuildUpdatesForLayer(static_cast<ReadbackLayer*>(l));
}
}
}
static Layer*
FindBackgroundLayer(ReadbackLayer* aLayer, nsIntPoint* aOffset)
{
gfxMatrix transform;
if (!aLayer->GetTransform().Is2D(&transform) ||
transform.HasNonIntegerTranslation())
return nsnull;
nsIntPoint transformOffset(PRInt32(transform.x0), PRInt32(transform.y0));
for (Layer* l = aLayer->GetPrevSibling(); l; l = l->GetPrevSibling()) {
gfxMatrix backgroundTransform;
if (!l->GetTransform().Is2D(&backgroundTransform) ||
backgroundTransform.HasNonIntegerTranslation())
return nsnull;
nsIntPoint backgroundOffset(PRInt32(backgroundTransform.x0), PRInt32(backgroundTransform.y0));
nsIntRect rectInBackground(transformOffset - backgroundOffset, aLayer->GetSize());
const nsIntRegion& visibleRegion = l->GetEffectiveVisibleRegion();
if (!visibleRegion.Intersects(rectInBackground))
continue;
// Since l is present in the background, from here on we either choose l
// or nothing.
if (!visibleRegion.Contains(rectInBackground))
return nsnull;
if (l->GetEffectiveOpacity() != 1.0 ||
!(l->GetContentFlags() & Layer::CONTENT_OPAQUE))
return nsnull;
// cliprects are post-transform
const nsIntRect* clipRect = l->GetEffectiveClipRect();
if (clipRect && !clipRect->Contains(nsIntRect(transformOffset, aLayer->GetSize())))
return nsnull;
Layer::LayerType type = l->GetType();
if (type != Layer::TYPE_COLOR && type != Layer::TYPE_THEBES)
return nsnull;
*aOffset = backgroundOffset - transformOffset;
return l;
}
return nsnull;
}
void
ReadbackProcessor::BuildUpdatesForLayer(ReadbackLayer* aLayer)
{
if (!aLayer->mSink)
return;
nsIntPoint offset;
Layer* newBackground = FindBackgroundLayer(aLayer, &offset);
if (!newBackground) {
aLayer->SetUnknown();
return;
}
if (newBackground->GetType() == Layer::TYPE_COLOR) {
ColorLayer* colorLayer = static_cast<ColorLayer*>(newBackground);
if (aLayer->mBackgroundColor != colorLayer->GetColor()) {
aLayer->mBackgroundLayer = nsnull;
aLayer->mBackgroundColor = colorLayer->GetColor();
NS_ASSERTION(aLayer->mBackgroundColor.a == 1.0,
"Color layer said it was opaque!");
nsRefPtr<gfxContext> ctx =
aLayer->mSink->BeginUpdate(aLayer->GetRect(),
aLayer->AllocateSequenceNumber());
if (ctx) {
ctx->SetColor(aLayer->mBackgroundColor);
nsIntSize size = aLayer->GetSize();
ctx->Rectangle(gfxRect(0, 0, size.width, size.height));
ctx->Fill();
aLayer->mSink->EndUpdate(ctx, aLayer->GetRect());
}
}
} else {
NS_ASSERTION(newBackground->AsThebesLayer(), "Must be ThebesLayer");
ThebesLayer* thebesLayer = static_cast<ThebesLayer*>(newBackground);
// updateRect is relative to the ThebesLayer
nsIntRect updateRect = aLayer->GetRect() - offset;
if (thebesLayer != aLayer->mBackgroundLayer ||
offset != aLayer->mBackgroundLayerOffset) {
aLayer->mBackgroundLayer = thebesLayer;
aLayer->mBackgroundLayerOffset = offset;
aLayer->mBackgroundColor = gfxRGBA(0,0,0,0);
thebesLayer->SetUsedForReadback(true);
} else {
nsIntRegion invalid;
invalid.Sub(updateRect, thebesLayer->GetValidRegion());
updateRect = invalid.GetBounds();
}
Update update = { aLayer, updateRect, aLayer->AllocateSequenceNumber() };
mAllUpdates.AppendElement(update);
}
}
void
ReadbackProcessor::GetThebesLayerUpdates(ThebesLayer* aLayer,
nsTArray<Update>* aUpdates,
nsIntRegion* aUpdateRegion)
{
// All ThebesLayers used for readback are in mAllUpdates (some possibly
// with an empty update rect).
aLayer->SetUsedForReadback(false);
if (aUpdateRegion) {
aUpdateRegion->SetEmpty();
}
for (PRUint32 i = mAllUpdates.Length(); i > 0; --i) {
const Update& update = mAllUpdates[i - 1];
if (update.mLayer->mBackgroundLayer == aLayer) {
aLayer->SetUsedForReadback(true);
// Don't bother asking for updates if we have an empty update rect.
if (!update.mUpdateRect.IsEmpty()) {
aUpdates->AppendElement(update);
if (aUpdateRegion) {
aUpdateRegion->Or(*aUpdateRegion, update.mUpdateRect);
}
}
mAllUpdates.RemoveElementAt(i - 1);
}
}
}
ReadbackProcessor::~ReadbackProcessor()
{
for (PRUint32 i = mAllUpdates.Length(); i > 0; --i) {
const Update& update = mAllUpdates[i - 1];
// Unprocessed update. Notify the readback sink that this content is
// unknown.
update.mLayer->SetUnknown();
}
}
}
}