gecko/layout/base/DisplayListClipState.cpp
2013-04-05 00:36:45 +13:00

93 lines
3.0 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 "DisplayListClipState.h"
#include "nsDisplayList.h"
namespace mozilla {
const DisplayItemClip*
DisplayListClipState::GetCurrentCombinedClip(nsDisplayListBuilder* aBuilder)
{
if (mCurrentCombinedClip) {
return mCurrentCombinedClip;
}
if (!mClipContentDescendants && !mClipContainingBlockDescendants) {
return nullptr;
}
void* mem = aBuilder->Allocate(sizeof(DisplayItemClip));
if (mClipContentDescendants) {
DisplayItemClip* newClip =
new (mem) DisplayItemClip(*mClipContentDescendants);
if (mClipContainingBlockDescendants) {
newClip->IntersectWith(*mClipContainingBlockDescendants);
}
mCurrentCombinedClip = newClip;
} else {
mCurrentCombinedClip =
new (mem) DisplayItemClip(*mClipContainingBlockDescendants);
}
return mCurrentCombinedClip;
}
void
DisplayListClipState::ClipContainingBlockDescendants(const nsRect& aRect,
const nscoord* aRadii,
DisplayItemClip& aClipOnStack)
{
if (aRadii) {
aClipOnStack.SetTo(aRect, aRadii);
} else {
aClipOnStack.SetTo(aRect);
}
if (mClipContainingBlockDescendants) {
aClipOnStack.IntersectWith(*mClipContainingBlockDescendants);
}
mClipContainingBlockDescendants = &aClipOnStack;
mCurrentCombinedClip = nullptr;
}
void
DisplayListClipState::ClipContentDescendants(const nsRect& aRect,
DisplayItemClip& aClipOnStack)
{
aClipOnStack.SetTo(aRect);
if (mClipContentDescendants) {
aClipOnStack.IntersectWith(*mClipContentDescendants);
}
mClipContentDescendants = &aClipOnStack;
mCurrentCombinedClip = nullptr;
}
void
DisplayListClipState::ClipContainingBlockDescendantsToContentBox(nsDisplayListBuilder* aBuilder,
nsIFrame* aFrame,
DisplayItemClip& aClipOnStack,
uint32_t aFlags)
{
nscoord radii[8];
bool hasBorderRadius = aFrame->GetContentBoxBorderRadii(radii);
if (!hasBorderRadius && (aFlags & ASSUME_DRAWING_RESTRICTED_TO_CONTENT_RECT)) {
return;
}
nsRect clipRect = aFrame->GetContentRectRelativeToSelf() +
aBuilder->ToReferenceFrame(aFrame);
// If we have a border-radius, we have to clip our content to that
// radius.
ClipContainingBlockDescendants(clipRect, hasBorderRadius ? radii : nullptr,
aClipOnStack);
}
DisplayListClipState::AutoSaveRestore::AutoSaveRestore(nsDisplayListBuilder* aBuilder)
: mState(aBuilder->ClipState())
, mSavedState(aBuilder->ClipState())
, mClipUsed(false)
, mRestored(false)
{}
}