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/* -*- Mode: C++; tab-width: 4; 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
#include "gfxBlur.h"
#include "gfx2DGlue.h"
#include "gfxContext.h"
#include "gfxPlatform.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/gfx/Blur.h"
#include "mozilla/gfx/PathHelpers.h"
#include "mozilla/Maybe.h"
#include "nsExpirationTracker.h"
#include "nsClassHashtable.h"
#include "gfxUtils.h"
#include <limits>
#include <cmath>
using namespace mozilla;
using namespace mozilla::gfx;
gfxAlphaBoxBlur::~gfxAlphaBoxBlur() = default;
UniquePtr<gfxContext> gfxAlphaBoxBlur::Init(gfxContext* aDestinationCtx,
const gfxRect& aRect,
const IntSize& aSpreadRadius,
const IntSize& aBlurRadius,
const gfxRect* aDirtyRect,
const gfxRect* aSkipRect,
bool aUseHardwareAccel) {
DrawTarget* refDT = aDestinationCtx->GetDrawTarget();
Maybe<Rect> dirtyRect = aDirtyRect ? Some(ToRect(*aDirtyRect)) : Nothing();
Maybe<Rect> skipRect = aSkipRect ? Some(ToRect(*aSkipRect)) : Nothing();
RefPtr<DrawTarget> dt = InitDrawTarget(
refDT, ToRect(aRect), aSpreadRadius, aBlurRadius,
dirtyRect.ptrOr(nullptr), skipRect.ptrOr(nullptr), aUseHardwareAccel);
if (!dt || !dt->IsValid()) {
return nullptr;
}
auto context = MakeUnique<gfxContext>(dt);
context->SetMatrix(Matrix::Translation(-mBlur.GetRect().TopLeft()));
return context;
}
already_AddRefed<DrawTarget> gfxAlphaBoxBlur::InitDrawTarget(
const DrawTarget* aReferenceDT, const Rect& aRect,
const IntSize& aSpreadRadius, const IntSize& aBlurRadius,
const Rect* aDirtyRect, const Rect* aSkipRect, bool aUseHardwareAccel) {
mBlur.Init(aRect, aSpreadRadius, aBlurRadius, aDirtyRect, aSkipRect);
size_t blurDataSize = mBlur.GetSurfaceAllocationSize();
if (blurDataSize == 0) {
return nullptr;
}
BackendType backend = aReferenceDT->GetBackendType();
// Check if the backend has an accelerated DrawSurfaceWithShadow.
// Currently, only D2D1.1 supports this.
// Otherwise, DrawSurfaceWithShadow only supports square blurs without spread.
// When blurring small draw targets such as short spans text, the cost of
// creating and flushing an accelerated draw target may exceed the speedup
// gained from the faster blur. It's up to the users of this blur
// to determine whether they want to use hardware acceleration.
if (aBlurRadius.IsSquare() && aSpreadRadius.IsEmpty() && aUseHardwareAccel &&
backend == BackendType::DIRECT2D1_1) {
mAccelerated = true;
}
if (mAccelerated) {
// Note: CreateShadowDrawTarget is only implemented for Cairo.
mDrawTarget = aReferenceDT->CreateShadowDrawTarget(
mBlur.GetSize(), SurfaceFormat::A8,
AlphaBoxBlur::CalculateBlurSigma(aBlurRadius.width));
if (mDrawTarget) {
mDrawTarget->ClearRect(gfx::Rect());
}
} else {
// Make an alpha-only surface to draw on. We will play with the data after
// everything is drawn to create a blur effect.
// This will be freed when the DrawTarget dies
mData = static_cast<uint8_t*>(calloc(1, blurDataSize));
if (!mData) {
return nullptr;
}
mDrawTarget =
Factory::DoesBackendSupportDataDrawtarget(backend)
? Factory::CreateDrawTargetForData(backend, mData, mBlur.GetSize(),
mBlur.GetStride(),
SurfaceFormat::A8)
: gfxPlatform::CreateDrawTargetForData(
mData, mBlur.GetSize(), mBlur.GetStride(), SurfaceFormat::A8);
}
if (!mDrawTarget || !mDrawTarget->IsValid()) {
if (mData) {
free(mData);
}
return nullptr;
}
if (mData) {
mDrawTarget->AddUserData(reinterpret_cast<UserDataKey*>(mDrawTarget.get()),
mData, free);
}
mDrawTarget->SetTransform(Matrix::Translation(-mBlur.GetRect().TopLeft()));
return do_AddRef(mDrawTarget);
}
already_AddRefed<SourceSurface> gfxAlphaBoxBlur::DoBlur(
const sRGBColor* aShadowColor, IntPoint* aOutTopLeft) {
if (aOutTopLeft) {
*aOutTopLeft = mBlur.GetRect().TopLeft();
}
RefPtr<SourceSurface> blurMask;
if (mData) {
mBlur.Blur(mData);
blurMask = mDrawTarget->Snapshot();
} else if (mAccelerated) {
blurMask = mDrawTarget->Snapshot();
RefPtr<DrawTarget> blurDT = mDrawTarget->CreateSimilarDrawTarget(
blurMask->GetSize(), SurfaceFormat::A8);
if (!blurDT) {
return nullptr;
}
blurDT->DrawSurfaceWithShadow(
blurMask, Point(0, 0),
ShadowOptions(
DeviceColor::MaskOpaqueWhite(), Point(0, 0),
AlphaBoxBlur::CalculateBlurSigma(mBlur.GetBlurRadius().width)),
CompositionOp::OP_OVER);
blurMask = blurDT->Snapshot();
}
if (!aShadowColor) {
return blurMask.forget();
}
RefPtr<DrawTarget> shadowDT = mDrawTarget->CreateSimilarDrawTarget(
blurMask->GetSize(), SurfaceFormat::B8G8R8A8);
if (!shadowDT) {
return nullptr;
}
ColorPattern shadowColor(ToDeviceColor(*aShadowColor));
shadowDT->MaskSurface(shadowColor, blurMask, Point(0, 0));
return shadowDT->Snapshot();
}
void gfxAlphaBoxBlur::Paint(gfxContext* aDestinationCtx) {
if (mDrawTarget && !mAccelerated && !mData) {
return;
}
DrawTarget* dest = aDestinationCtx->GetDrawTarget();
if (!dest) {
NS_WARNING("Blurring not supported for Thebes contexts!");
return;
}
RefPtr<gfxPattern> thebesPat = aDestinationCtx->GetPattern();
Pattern* pat = thebesPat->GetPattern(dest, nullptr);
if (!pat) {
NS_WARNING("Failed to get pattern for blur!");
return;
}
IntPoint topLeft;
RefPtr<SourceSurface> mask = DoBlur(nullptr, &topLeft);
if (!mask) {
NS_ERROR("Failed to create mask!");
return;
}
// Avoid a semi-expensive clip operation if we can, otherwise
// clip to the dirty rect
Rect* dirtyRect = mBlur.GetDirtyRect();
if (dirtyRect) {
dest->PushClipRect(*dirtyRect);
}
Matrix oldTransform = dest->GetTransform();
Matrix newTransform = oldTransform;
newTransform.PreTranslate(topLeft);
dest->SetTransform(newTransform);
dest->MaskSurface(*pat, mask, Point(0, 0));
dest->SetTransform(oldTransform);
if (dirtyRect) {
dest->PopClip();
}
}
IntSize gfxAlphaBoxBlur::CalculateBlurRadius(const gfxPoint& aStd) {
mozilla::gfx::Point std(Float(aStd.x), Float(aStd.y));
IntSize size = AlphaBoxBlur::CalculateBlurRadius(std);
return IntSize(size.width, size.height);
}
struct BlurCacheKey : public PLDHashEntryHdr {
typedef const BlurCacheKey& KeyType;
typedef const BlurCacheKey* KeyTypePointer;
enum { ALLOW_MEMMOVE = true };
IntSize mMinSize;
IntSize mBlurRadius;
sRGBColor mShadowColor;
BackendType mBackend;
RectCornerRadii mCornerRadii;
bool mIsInset;
// Only used for inset blurs
IntSize mInnerMinSize;
BlurCacheKey(const IntSize& aMinSize, const IntSize& aBlurRadius,
const RectCornerRadii* aCornerRadii,
const sRGBColor& aShadowColor, BackendType aBackendType)
: BlurCacheKey(aMinSize, IntSize(0, 0), aBlurRadius, aCornerRadii,
aShadowColor, false, aBackendType) {}
explicit BlurCacheKey(const BlurCacheKey* aOther)
: mMinSize(aOther->mMinSize),
mBlurRadius(aOther->mBlurRadius),
mShadowColor(aOther->mShadowColor),
mBackend(aOther->mBackend),
mCornerRadii(aOther->mCornerRadii),
mIsInset(aOther->mIsInset),
mInnerMinSize(aOther->mInnerMinSize) {}
explicit BlurCacheKey(const IntSize& aOuterMinSize,
const IntSize& aInnerMinSize,
const IntSize& aBlurRadius,
const RectCornerRadii* aCornerRadii,
const sRGBColor& aShadowColor, bool aIsInset,
BackendType aBackendType)
: mMinSize(aOuterMinSize),
mBlurRadius(aBlurRadius),
mShadowColor(aShadowColor),
mBackend(aBackendType),
mCornerRadii(aCornerRadii ? *aCornerRadii : RectCornerRadii()),
mIsInset(aIsInset),
mInnerMinSize(aInnerMinSize) {}
BlurCacheKey(BlurCacheKey&&) = default;
static PLDHashNumber HashKey(const KeyTypePointer aKey) {
PLDHashNumber hash = 0;
hash = AddToHash(hash, aKey->mMinSize.width, aKey->mMinSize.height);
hash = AddToHash(hash, aKey->mBlurRadius.width, aKey->mBlurRadius.height);
hash = AddToHash(
hash, HashBytes(&aKey->mShadowColor.r, sizeof(aKey->mShadowColor.r)));
hash = AddToHash(
hash, HashBytes(&aKey->mShadowColor.g, sizeof(aKey->mShadowColor.g)));
hash = AddToHash(
hash, HashBytes(&aKey->mShadowColor.b, sizeof(aKey->mShadowColor.b)));
hash = AddToHash(
hash, HashBytes(&aKey->mShadowColor.a, sizeof(aKey->mShadowColor.a)));
for (int i = 0; i < 4; i++) {
hash = AddToHash(hash, aKey->mCornerRadii[i].width,
aKey->mCornerRadii[i].height);
}
hash = AddToHash(hash, (uint32_t)aKey->mBackend);
if (aKey->mIsInset) {
hash = AddToHash(hash, aKey->mInnerMinSize.width,
aKey->mInnerMinSize.height);
}
return hash;
}
bool KeyEquals(KeyTypePointer aKey) const {
if (aKey->mMinSize == mMinSize && aKey->mBlurRadius == mBlurRadius &&
aKey->mCornerRadii == mCornerRadii &&
aKey->mShadowColor == mShadowColor && aKey->mBackend == mBackend) {
if (mIsInset) {
return (mInnerMinSize == aKey->mInnerMinSize);
}
return true;
}
return false;
}
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
};
/**
* This class is what is cached. It need to be allocated in an object separated
* to the cache entry to be able to be tracked by the nsExpirationTracker.
* */
struct BlurCacheData {
BlurCacheData(SourceSurface* aBlur, const IntMargin& aBlurMargin,
BlurCacheKey&& aKey)
: mBlur(aBlur), mBlurMargin(aBlurMargin), mKey(std::move(aKey)) {}
BlurCacheData(BlurCacheData&& aOther) = default;
nsExpirationState* GetExpirationState() { return &mExpirationState; }
nsExpirationState mExpirationState;
RefPtr<SourceSurface> mBlur;
IntMargin mBlurMargin;
BlurCacheKey mKey;
};
/**
* This class implements a cache with no maximum size, that retains the
* SourceSurfaces used to draw the blurs.
*
* An entry stays in the cache as long as it is used often.
*/
class BlurCache final : public nsExpirationTracker<BlurCacheData, 4> {
public:
BlurCache()
: nsExpirationTracker<BlurCacheData, 4>(GENERATION_MS, "BlurCache") {}
virtual void NotifyExpired(BlurCacheData* aObject) override {
RemoveObject(aObject);
mHashEntries.Remove(aObject->mKey);
}
BlurCacheData* Lookup(const IntSize& aMinSize, const IntSize& aBlurRadius,
const RectCornerRadii* aCornerRadii,
const sRGBColor& aShadowColor,
BackendType aBackendType) {
BlurCacheData* blur = mHashEntries.Get(BlurCacheKey(
aMinSize, aBlurRadius, aCornerRadii, aShadowColor, aBackendType));
if (blur) {
MarkUsed(blur);
}
return blur;
}
BlurCacheData* LookupInsetBoxShadow(const IntSize& aOuterMinSize,
const IntSize& aInnerMinSize,
const IntSize& aBlurRadius,
const RectCornerRadii* aCornerRadii,
const sRGBColor& aShadowColor,
BackendType aBackendType) {
bool insetBoxShadow = true;
BlurCacheKey key(aOuterMinSize, aInnerMinSize, aBlurRadius, aCornerRadii,
aShadowColor, insetBoxShadow, aBackendType);
BlurCacheData* blur = mHashEntries.Get(key);
if (blur) {
MarkUsed(blur);
}
return blur;
}
void RegisterEntry(UniquePtr<BlurCacheData> aValue) {
nsresult rv = AddObject(aValue.get());
if (NS_FAILED(rv)) {
// We are OOM, and we cannot track this object. We don't want stall
// entries in the hash table (since the expiration tracker is responsible
// for removing the cache entries), so we avoid putting that entry in the
// table, which is a good thing considering we are short on memory
// anyway, we probably don't want to retain things.
return;
}
mHashEntries.InsertOrUpdate(aValue->mKey, std::move(aValue));
}
protected:
static const uint32_t GENERATION_MS = 1000;
/**
* FIXME use nsTHashtable to avoid duplicating the BlurCacheKey.
*/
nsClassHashtable<BlurCacheKey, BlurCacheData> mHashEntries;
};
static BlurCache* gBlurCache = nullptr;
static IntSize ComputeMinSizeForShadowShape(const RectCornerRadii* aCornerRadii,
const IntSize& aBlurRadius,
IntMargin& aOutSlice,
const IntSize& aRectSize) {
Size cornerSize(0, 0);
if (aCornerRadii) {
const RectCornerRadii& corners = *aCornerRadii;
for (const auto i : mozilla::AllPhysicalCorners()) {
cornerSize.width = std::max(cornerSize.width, corners[i].width);
cornerSize.height = std::max(cornerSize.height, corners[i].height);
}
}
IntSize margin = IntSize::Ceil(cornerSize) + aBlurRadius;
aOutSlice =
IntMargin(margin.height, margin.width, margin.height, margin.width);
IntSize minSize(aOutSlice.LeftRight() + 1, aOutSlice.TopBottom() + 1);
// If aRectSize is smaller than minSize, the border-image approach won't
// work; there's no way to squeeze parts of the min box-shadow source
// image such that the result looks correct. So we need to adjust minSize
// in such a way that we can later draw it without stretching in the affected
// dimension. We also need to adjust "slice" to ensure that we're not trying
// to slice away more than we have.
if (aRectSize.width < minSize.width) {
minSize.width = aRectSize.width;
aOutSlice.left = 0;
aOutSlice.right = 0;
}
if (aRectSize.height < minSize.height) {
minSize.height = aRectSize.height;
aOutSlice.top = 0;
aOutSlice.bottom = 0;
}
MOZ_ASSERT(aOutSlice.LeftRight() <= minSize.width);
MOZ_ASSERT(aOutSlice.TopBottom() <= minSize.height);
return minSize;
}
static void CacheBlur(DrawTarget* aDT, const IntSize& aMinSize,
const IntSize& aBlurRadius,
const RectCornerRadii* aCornerRadii,
const sRGBColor& aShadowColor,
const IntMargin& aBlurMargin, SourceSurface* aBoxShadow) {
gBlurCache->RegisterEntry(MakeUnique<BlurCacheData>(
aBoxShadow, aBlurMargin,
BlurCacheKey(aMinSize, aBlurRadius, aCornerRadii, aShadowColor,
aDT->GetBackendType())));
}
// Blurs a small surface and creates the colored box shadow.
static already_AddRefed<SourceSurface> CreateBoxShadow(
DrawTarget* aDestDrawTarget, const IntSize& aMinSize,
const RectCornerRadii* aCornerRadii, const IntSize& aBlurRadius,
const sRGBColor& aShadowColor, bool aMirrorCorners,
IntMargin& aOutBlurMargin) {
gfxAlphaBoxBlur blur;
Rect minRect(Point(0, 0), Size(aMinSize));
Rect blurRect(minRect);
// If mirroring corners, we only need to draw the top-left quadrant.
// Use ceil to preserve the remaining 1x1 middle area for minimized box
// shadows.
if (aMirrorCorners) {
blurRect.SizeTo(ceil(blurRect.Width() * 0.5f),
ceil(blurRect.Height() * 0.5f));
}
IntSize zeroSpread(0, 0);
RefPtr<DrawTarget> blurDT =
blur.InitDrawTarget(aDestDrawTarget, blurRect, zeroSpread, aBlurRadius);
if (!blurDT) {
return nullptr;
}
ColorPattern black(DeviceColor::MaskOpaqueBlack());
if (aCornerRadii) {
RefPtr<Path> roundedRect =
MakePathForRoundedRect(*blurDT, minRect, *aCornerRadii);
blurDT->Fill(roundedRect, black);
} else {
blurDT->FillRect(minRect, black);
}
IntPoint topLeft;
RefPtr<SourceSurface> result = blur.DoBlur(&aShadowColor, &topLeft);
if (!result) {
return nullptr;
}
// Since blurRect is at (0, 0), we can find the inflated margin by
// negating the new rect origin, which would have been negative if
// the rect was inflated.
aOutBlurMargin = IntMargin(-topLeft.y, -topLeft.x, -topLeft.y, -topLeft.x);
return result.forget();
}
static already_AddRefed<SourceSurface> GetBlur(
gfxContext* aDestinationCtx, const IntSize& aRectSize,
const IntSize& aBlurRadius, const RectCornerRadii* aCornerRadii,
const sRGBColor& aShadowColor, bool aMirrorCorners,
IntMargin& aOutBlurMargin, IntMargin& aOutSlice, IntSize& aOutMinSize) {
if (!gBlurCache) {
gBlurCache = new BlurCache();
}
IntSize minSize = ComputeMinSizeForShadowShape(aCornerRadii, aBlurRadius,
aOutSlice, aRectSize);
// We can get seams using the min size rect when drawing to the destination
// rect if we have a non-pixel aligned destination transformation. In those
// cases, fallback to just rendering the destination rect. During printing, we
// record all the Moz 2d commands and replay them on the parent side with
// Cairo. Cairo printing uses StretchDIBits to stretch the surface. However,
// since our source image is only 1px for some parts, we make thousands of
// calls. Instead just render the blur ourself here as one image and send it
// over for printing.
// TODO: May need to change this with the blob renderer in WR since it also
// records.
Matrix destMatrix = aDestinationCtx->CurrentMatrix();
bool useDestRect = !destMatrix.IsRectilinear() ||
destMatrix.HasNonIntegerTranslation() ||
aDestinationCtx->GetDrawTarget()->IsRecording();
if (useDestRect) {
minSize = aRectSize;
}
int32_t maxTextureSize = gfxPlatform::MaxTextureSize();
if (minSize.width > maxTextureSize || minSize.height > maxTextureSize) {
return nullptr;
}
aOutMinSize = minSize;
DrawTarget* destDT = aDestinationCtx->GetDrawTarget();
if (!useDestRect) {
BlurCacheData* cached =
gBlurCache->Lookup(minSize, aBlurRadius, aCornerRadii, aShadowColor,
destDT->GetBackendType());
if (cached) {
// See CreateBoxShadow() for these values
aOutBlurMargin = cached->mBlurMargin;
RefPtr<SourceSurface> blur = cached->mBlur;
return blur.forget();
}
}
RefPtr<SourceSurface> boxShadow =
CreateBoxShadow(destDT, minSize, aCornerRadii, aBlurRadius, aShadowColor,
aMirrorCorners, aOutBlurMargin);
if (!boxShadow) {
return nullptr;
}
if (RefPtr<SourceSurface> opt = destDT->OptimizeSourceSurface(boxShadow)) {
boxShadow = opt;
}
if (!useDestRect) {
CacheBlur(destDT, minSize, aBlurRadius, aCornerRadii, aShadowColor,
aOutBlurMargin, boxShadow);
}
return boxShadow.forget();
}
void gfxAlphaBoxBlur::ShutdownBlurCache() {
delete gBlurCache;
gBlurCache = nullptr;
}
static Rect RectWithEdgesTRBL(Float aTop, Float aRight, Float aBottom,
Float aLeft) {
return Rect(aLeft, aTop, aRight - aLeft, aBottom - aTop);
}
static bool ShouldStretchSurface(DrawTarget* aDT, SourceSurface* aSurface) {
// Use stretching if possible, since it leads to less seams when the
// destination is transformed. However, don't do this if we're using cairo,
// because if cairo is using pixman it won't render anything for large
// stretch factors because pixman's internal fixed point precision is not
// high enough to handle those scale factors.
return aDT->GetBackendType() != BackendType::CAIRO;
}
static void RepeatOrStretchSurface(DrawTarget* aDT, SourceSurface* aSurface,
const Rect& aDest, const Rect& aSrc,
const Rect& aSkipRect) {
if (aSkipRect.Contains(aDest)) {
return;
}
if (ShouldStretchSurface(aDT, aSurface)) {
aDT->DrawSurface(aSurface, aDest, aSrc);
return;
}
SurfacePattern pattern(aSurface, ExtendMode::REPEAT,
Matrix::Translation(aDest.TopLeft() - aSrc.TopLeft()),
SamplingFilter::GOOD, RoundedToInt(aSrc));
aDT->FillRect(aDest, pattern);
}
static void DrawCorner(DrawTarget* aDT, SourceSurface* aSurface,
const Rect& aDest, const Rect& aSrc,
const Rect& aSkipRect) {
if (aSkipRect.Contains(aDest)) {
return;
}
aDT->DrawSurface(aSurface, aDest, aSrc);
}
static void DrawMinBoxShadow(DrawTarget* aDestDrawTarget,
SourceSurface* aSourceBlur, const Rect& aDstOuter,
const Rect& aDstInner, const Rect& aSrcOuter,
const Rect& aSrcInner, const Rect& aSkipRect,
bool aMiddle = false) {
// Corners: top left, top right, bottom left, bottom right
DrawCorner(aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstOuter.Y(), aDstInner.X(), aDstInner.Y(),
aDstOuter.X()),
RectWithEdgesTRBL(aSrcOuter.Y(), aSrcInner.X(), aSrcInner.Y(),
aSrcOuter.X()),
aSkipRect);
DrawCorner(aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstOuter.Y(), aDstOuter.XMost(), aDstInner.Y(),
aDstInner.XMost()),
RectWithEdgesTRBL(aSrcOuter.Y(), aSrcOuter.XMost(), aSrcInner.Y(),
aSrcInner.XMost()),
aSkipRect);
DrawCorner(aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstInner.YMost(), aDstInner.X(),
aDstOuter.YMost(), aDstOuter.X()),
RectWithEdgesTRBL(aSrcInner.YMost(), aSrcInner.X(),
aSrcOuter.YMost(), aSrcOuter.X()),
aSkipRect);
DrawCorner(aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstInner.YMost(), aDstOuter.XMost(),
aDstOuter.YMost(), aDstInner.XMost()),
RectWithEdgesTRBL(aSrcInner.YMost(), aSrcOuter.XMost(),
aSrcOuter.YMost(), aSrcInner.XMost()),
aSkipRect);
// Edges: top, left, right, bottom
RepeatOrStretchSurface(aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstOuter.Y(), aDstInner.XMost(),
aDstInner.Y(), aDstInner.X()),
RectWithEdgesTRBL(aSrcOuter.Y(), aSrcInner.XMost(),
aSrcInner.Y(), aSrcInner.X()),
aSkipRect);
RepeatOrStretchSurface(aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstInner.Y(), aDstInner.X(),
aDstInner.YMost(), aDstOuter.X()),
RectWithEdgesTRBL(aSrcInner.Y(), aSrcInner.X(),
aSrcInner.YMost(), aSrcOuter.X()),
aSkipRect);
RepeatOrStretchSurface(
aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstInner.Y(), aDstOuter.XMost(), aDstInner.YMost(),
aDstInner.XMost()),
RectWithEdgesTRBL(aSrcInner.Y(), aSrcOuter.XMost(), aSrcInner.YMost(),
aSrcInner.XMost()),
aSkipRect);
RepeatOrStretchSurface(aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstInner.YMost(), aDstInner.XMost(),
aDstOuter.YMost(), aDstInner.X()),
RectWithEdgesTRBL(aSrcInner.YMost(), aSrcInner.XMost(),
aSrcOuter.YMost(), aSrcInner.X()),
aSkipRect);
// Middle part
if (aMiddle) {
RepeatOrStretchSurface(aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstInner.Y(), aDstInner.XMost(),
aDstInner.YMost(), aDstInner.X()),
RectWithEdgesTRBL(aSrcInner.Y(), aSrcInner.XMost(),
aSrcInner.YMost(), aSrcInner.X()),
aSkipRect);
}
}
static void DrawMirroredRect(DrawTarget* aDT, SourceSurface* aSurface,
const Rect& aDest, const Point& aSrc,
Float aScaleX, Float aScaleY) {
SurfacePattern pattern(
aSurface, ExtendMode::CLAMP,
Matrix::Scaling(aScaleX, aScaleY)
.PreTranslate(-aSrc)
.PostTranslate(aScaleX < 0 ? aDest.XMost() : aDest.X(),
aScaleY < 0 ? aDest.YMost() : aDest.Y()));
aDT->FillRect(aDest, pattern);
}
static void DrawMirroredBoxShadow(DrawTarget* aDT, SourceSurface* aSurface,
const Rect& aDestRect) {
Point center(ceil(aDestRect.X() + aDestRect.Width() / 2),
ceil(aDestRect.Y() + aDestRect.Height() / 2));
Rect topLeft(aDestRect.X(), aDestRect.Y(), center.x - aDestRect.X(),
center.y - aDestRect.Y());
Rect bottomRight(topLeft.BottomRight(), aDestRect.Size() - topLeft.Size());
Rect topRight(bottomRight.X(), topLeft.Y(), bottomRight.Width(),
topLeft.Height());
Rect bottomLeft(topLeft.X(), bottomRight.Y(), topLeft.Width(),
bottomRight.Height());
DrawMirroredRect(aDT, aSurface, topLeft, Point(), 1, 1);
DrawMirroredRect(aDT, aSurface, topRight, Point(), -1, 1);
DrawMirroredRect(aDT, aSurface, bottomLeft, Point(), 1, -1);
DrawMirroredRect(aDT, aSurface, bottomRight, Point(), -1, -1);
}
static void DrawMirroredCorner(DrawTarget* aDT, SourceSurface* aSurface,
const Rect& aDest, const Point& aSrc,
const Rect& aSkipRect, Float aScaleX,
Float aScaleY) {
if (aSkipRect.Contains(aDest)) {
return;
}
DrawMirroredRect(aDT, aSurface, aDest, aSrc, aScaleX, aScaleY);
}
static void RepeatOrStretchMirroredSurface(DrawTarget* aDT,
SourceSurface* aSurface,
const Rect& aDest, const Rect& aSrc,
const Rect& aSkipRect, Float aScaleX,
Float aScaleY) {
if (aSkipRect.Contains(aDest)) {
return;
}
if (ShouldStretchSurface(aDT, aSurface)) {
aScaleX *= aDest.Width() / aSrc.Width();
aScaleY *= aDest.Height() / aSrc.Height();
DrawMirroredRect(aDT, aSurface, aDest, aSrc.TopLeft(), aScaleX, aScaleY);
return;
}
SurfacePattern pattern(
aSurface, ExtendMode::REPEAT,
Matrix::Scaling(aScaleX, aScaleY)
.PreTranslate(-aSrc.TopLeft())
.PostTranslate(aScaleX < 0 ? aDest.XMost() : aDest.X(),
aScaleY < 0 ? aDest.YMost() : aDest.Y()),
SamplingFilter::GOOD, RoundedToInt(aSrc));
aDT->FillRect(aDest, pattern);
}
static void DrawMirroredMinBoxShadow(
DrawTarget* aDestDrawTarget, SourceSurface* aSourceBlur,
const Rect& aDstOuter, const Rect& aDstInner, const Rect& aSrcOuter,
const Rect& aSrcInner, const Rect& aSkipRect, bool aMiddle = false) {
// Corners: top left, top right, bottom left, bottom right
// Compute quadrant bounds and then clip them to corners along
// dimensions where we need to stretch from min size.
Point center(ceil(aDstOuter.X() + aDstOuter.Width() / 2),
ceil(aDstOuter.Y() + aDstOuter.Height() / 2));
Rect topLeft(aDstOuter.X(), aDstOuter.Y(), center.x - aDstOuter.X(),
center.y - aDstOuter.Y());
Rect bottomRight(topLeft.BottomRight(), aDstOuter.Size() - topLeft.Size());
Rect topRight(bottomRight.X(), topLeft.Y(), bottomRight.Width(),
topLeft.Height());
Rect bottomLeft(topLeft.X(), bottomRight.Y(), topLeft.Width(),
bottomRight.Height());
// Check if the middle part has been minimized along each dimension.
// If so, those will be strecthed/drawn separately and need to be clipped out.
if (aSrcInner.Width() == 1) {
topLeft.SetRightEdge(aDstInner.X());
topRight.SetLeftEdge(aDstInner.XMost());
bottomLeft.SetRightEdge(aDstInner.X());
bottomRight.SetLeftEdge(aDstInner.XMost());
}
if (aSrcInner.Height() == 1) {
topLeft.SetBottomEdge(aDstInner.Y());
topRight.SetBottomEdge(aDstInner.Y());
bottomLeft.SetTopEdge(aDstInner.YMost());
bottomRight.SetTopEdge(aDstInner.YMost());
}
DrawMirroredCorner(aDestDrawTarget, aSourceBlur, topLeft, aSrcOuter.TopLeft(),
aSkipRect, 1, 1);
DrawMirroredCorner(aDestDrawTarget, aSourceBlur, topRight,
aSrcOuter.TopLeft(), aSkipRect, -1, 1);
DrawMirroredCorner(aDestDrawTarget, aSourceBlur, bottomLeft,
aSrcOuter.TopLeft(), aSkipRect, 1, -1);
DrawMirroredCorner(aDestDrawTarget, aSourceBlur, bottomRight,
aSrcOuter.TopLeft(), aSkipRect, -1, -1);
// Edges: top, bottom, left, right
// Draw middle edges where they need to be stretched. The top and left
// sections that are part of the top-left quadrant will be mirrored to
// the bottom and right sections, respectively.
if (aSrcInner.Width() == 1) {
Rect dstTop = RectWithEdgesTRBL(aDstOuter.Y(), aDstInner.XMost(),
aDstInner.Y(), aDstInner.X());
Rect srcTop = RectWithEdgesTRBL(aSrcOuter.Y(), aSrcInner.XMost(),
aSrcInner.Y(), aSrcInner.X());
Rect dstBottom = RectWithEdgesTRBL(aDstInner.YMost(), aDstInner.XMost(),
aDstOuter.YMost(), aDstInner.X());
Rect srcBottom = RectWithEdgesTRBL(aSrcOuter.Y(), aSrcInner.XMost(),
aSrcInner.Y(), aSrcInner.X());
// If we only need to stretch along the X axis and we're drawing
// the middle section, just sample all the way to the center of the
// source on the Y axis to avoid extra draw calls.
if (aMiddle && aSrcInner.Height() != 1) {
dstTop.SetBottomEdge(center.y);
srcTop.SetHeight(dstTop.Height());
dstBottom.SetTopEdge(dstTop.YMost());
srcBottom.SetHeight(dstBottom.Height());
}
RepeatOrStretchMirroredSurface(aDestDrawTarget, aSourceBlur, dstTop, srcTop,
aSkipRect, 1, 1);
RepeatOrStretchMirroredSurface(aDestDrawTarget, aSourceBlur, dstBottom,
srcBottom, aSkipRect, 1, -1);
}
if (aSrcInner.Height() == 1) {
Rect dstLeft = RectWithEdgesTRBL(aDstInner.Y(), aDstInner.X(),
aDstInner.YMost(), aDstOuter.X());
Rect srcLeft = RectWithEdgesTRBL(aSrcInner.Y(), aSrcInner.X(),
aSrcInner.YMost(), aSrcOuter.X());
Rect dstRight = RectWithEdgesTRBL(aDstInner.Y(), aDstOuter.XMost(),
aDstInner.YMost(), aDstInner.XMost());
Rect srcRight = RectWithEdgesTRBL(aSrcInner.Y(), aSrcInner.X(),
aSrcInner.YMost(), aSrcOuter.X());
// Only stretching on Y axis, so sample source to the center of the X axis.
if (aMiddle && aSrcInner.Width() != 1) {
dstLeft.SetRightEdge(center.x);
srcLeft.SetWidth(dstLeft.Width());
dstRight.SetLeftEdge(dstLeft.XMost());
srcRight.SetWidth(dstRight.Width());
}
RepeatOrStretchMirroredSurface(aDestDrawTarget, aSourceBlur, dstLeft,
srcLeft, aSkipRect, 1, 1);
RepeatOrStretchMirroredSurface(aDestDrawTarget, aSourceBlur, dstRight,
srcRight, aSkipRect, -1, 1);
}
// If we need to stretch along both dimensions, then the middle part
// must be drawn separately.
if (aMiddle && aSrcInner.Width() == 1 && aSrcInner.Height() == 1) {
RepeatOrStretchSurface(aDestDrawTarget, aSourceBlur,
RectWithEdgesTRBL(aDstInner.Y(), aDstInner.XMost(),
aDstInner.YMost(), aDstInner.X()),
RectWithEdgesTRBL(aSrcInner.Y(), aSrcInner.XMost(),
aSrcInner.YMost(), aSrcInner.X()),
aSkipRect);
}
}
/***
* We draw a blurred a rectangle by only blurring a smaller rectangle and
* splitting the rectangle into 9 parts.
* First, a small minimum source rect is calculated and used to create a blur
* mask since the actual blurring itself is expensive. Next, we use the mask
* with the given shadow color to create a minimally-sized box shadow of the
* right color. Finally, we cut out the 9 parts from the box-shadow source and
* paint each part in the right place, stretching the non-corner parts to fill
* the space between the corners.
*/
/* static */
void gfxAlphaBoxBlur::BlurRectangle(gfxContext* aDestinationCtx,
const gfxRect& aRect,
const RectCornerRadii* aCornerRadii,
const gfxPoint& aBlurStdDev,
const sRGBColor& aShadowColor,
const gfxRect& aDirtyRect,
const gfxRect& aSkipRect) {
if (!RectIsInt32Safe(ToRect(aRect))) {
return;
}
IntSize blurRadius = CalculateBlurRadius(aBlurStdDev);
bool mirrorCorners = !aCornerRadii || aCornerRadii->AreRadiiSame();
IntRect rect = RoundedToInt(ToRect(aRect));
IntMargin blurMargin;
IntMargin slice;
IntSize minSize;
RefPtr<SourceSurface> boxShadow =
GetBlur(aDestinationCtx, rect.Size(), blurRadius, aCornerRadii,
aShadowColor, mirrorCorners, blurMargin, slice, minSize);
if (!boxShadow) {
return;
}
DrawTarget* destDrawTarget = aDestinationCtx->GetDrawTarget();
destDrawTarget->PushClipRect(ToRect(aDirtyRect));
// Copy the right parts from boxShadow into destDrawTarget. The middle parts
// will be stretched, border-image style.
Rect srcOuter(Point(blurMargin.left, blurMargin.top), Size(minSize));
Rect srcInner(srcOuter);
srcOuter.Inflate(Margin(blurMargin));
srcInner.Deflate(Margin(slice));
Rect dstOuter(rect);
Rect dstInner(rect);
dstOuter.Inflate(Margin(blurMargin));
dstInner.Deflate(Margin(slice));
Rect skipRect = ToRect(aSkipRect);
if (minSize == rect.Size()) {
// The target rect is smaller than the minimal size so just draw the surface
if (mirrorCorners) {
DrawMirroredBoxShadow(destDrawTarget, boxShadow, dstOuter);
} else {
destDrawTarget->DrawSurface(boxShadow, dstOuter, srcOuter);
}
} else {
if (mirrorCorners) {
DrawMirroredMinBoxShadow(destDrawTarget, boxShadow, dstOuter, dstInner,
srcOuter, srcInner, skipRect, true);
} else {
DrawMinBoxShadow(destDrawTarget, boxShadow, dstOuter, dstInner, srcOuter,
srcInner, skipRect, true);
}
}
// A note about anti-aliasing and seems between adjacent parts:
// We don't explicitly disable anti-aliasing in the DrawSurface calls above,
// so if there's a transform on destDrawTarget that is not pixel-aligned,
// there will be seams between adjacent parts of the box-shadow. It's hard to
// avoid those without the use of an intermediate surface.
// You might think that we could avoid those by just turning off AA, but there
// is a problem with that: Box-shadow rendering needs to clip out the
// element's border box, and we'd like that clip to have anti-aliasing -
// especially if the element has rounded corners! So we can't do that unless
// we have a way to say "Please anti-alias the clip, but don't antialias the
// destination rect of the DrawSurface call".
destDrawTarget->PopClip();
}
static already_AddRefed<Path> GetBoxShadowInsetPath(
DrawTarget* aDrawTarget, const Rect aOuterRect, const Rect aInnerRect,
const RectCornerRadii* aInnerClipRadii) {
/***
* We create an inset path by having two rects.
*
* -----------------------
* | ________________ |
* | | | |
* | | | |
* | ------------------ |
* |_____________________|
*
* The outer rect and the inside rect. The path
* creates a frame around the content where we draw the inset shadow.
*/
RefPtr<PathBuilder> builder =
aDrawTarget->CreatePathBuilder(FillRule::FILL_EVEN_ODD);
AppendRectToPath(builder, aOuterRect, true);
if (aInnerClipRadii) {
AppendRoundedRectToPath(builder, aInnerRect, *aInnerClipRadii, false);
} else {
AppendRectToPath(builder, aInnerRect, false);
}
return builder->Finish();
}
static void FillDestinationPath(
gfxContext* aDestinationCtx, const Rect& aDestinationRect,
const Rect& aShadowClipRect, const sRGBColor& aShadowColor,
const RectCornerRadii* aInnerClipRadii = nullptr) {
// When there is no blur radius, fill the path onto the destination
// surface.
aDestinationCtx->SetColor(aShadowColor);
DrawTarget* destDrawTarget = aDestinationCtx->GetDrawTarget();
RefPtr<Path> shadowPath = GetBoxShadowInsetPath(
destDrawTarget, aDestinationRect, aShadowClipRect, aInnerClipRadii);
aDestinationCtx->SetPath(shadowPath);
aDestinationCtx->Fill();
}
static void CacheInsetBlur(const IntSize& aMinOuterSize,
const IntSize& aMinInnerSize,
const IntSize& aBlurRadius,
const RectCornerRadii* aCornerRadii,
const sRGBColor& aShadowColor,
BackendType aBackendType,
SourceSurface* aBoxShadow) {
bool isInsetBlur = true;
BlurCacheKey key(aMinOuterSize, aMinInnerSize, aBlurRadius, aCornerRadii,
aShadowColor, isInsetBlur, aBackendType);
IntMargin blurMargin(0, 0, 0, 0);
gBlurCache->RegisterEntry(
MakeUnique<BlurCacheData>(aBoxShadow, blurMargin, std::move(key)));
}
already_AddRefed<SourceSurface> gfxAlphaBoxBlur::GetInsetBlur(
const Rect& aOuterRect, const Rect& aWhitespaceRect, bool aIsDestRect,
const sRGBColor& aShadowColor, const IntSize& aBlurRadius,
const RectCornerRadii* aInnerClipRadii, DrawTarget* aDestDrawTarget,
bool aMirrorCorners) {
if (!gBlurCache) {
gBlurCache = new BlurCache();
}
IntSize outerSize = IntSize::Truncate(aOuterRect.Size());
IntSize whitespaceSize = IntSize::Truncate(aWhitespaceRect.Size());
if (!aIsDestRect) {
BlurCacheData* cached = gBlurCache->LookupInsetBoxShadow(
outerSize, whitespaceSize, aBlurRadius, aInnerClipRadii, aShadowColor,
aDestDrawTarget->GetBackendType());
if (cached) {
// So we don't forget the actual cached blur
RefPtr<SourceSurface> cachedBlur = cached->mBlur;
return cachedBlur.forget();
}
}
// If we can do a min rect, the whitespace rect will be expanded in Init to
// aOuterRect.
Rect blurRect = aIsDestRect ? aOuterRect : aWhitespaceRect;
// If mirroring corners, we only need to draw the top-left quadrant.
// Use ceil to preserve the remaining 1x1 middle area for minimized box
// shadows.
if (aMirrorCorners) {
blurRect.SizeTo(ceil(blurRect.Width() * 0.5f),
ceil(blurRect.Height() * 0.5f));
}
IntSize zeroSpread(0, 0);
RefPtr<DrawTarget> minDrawTarget =
InitDrawTarget(aDestDrawTarget, blurRect, zeroSpread, aBlurRadius);
if (!minDrawTarget) {
return nullptr;
}
// This is really annoying. When we create the AlphaBoxBlur, the DrawTarget
// has a translation applied to it that is the topLeft point. This is actually
// the rect we gave it plus the blur radius. The rects we give this for the
// outer and whitespace rects are based at (0, 0). We could either translate
// those rects when we don't have a destination rect or ignore the translation
// when using the dest rect. The dest rects layout gives us expect this
// translation.
if (!aIsDestRect) {
minDrawTarget->SetTransform(Matrix());
}
// Fill in the path between the inside white space / outer rects
// NOT the inner frame
RefPtr<Path> maskPath = GetBoxShadowInsetPath(
minDrawTarget, aOuterRect, aWhitespaceRect, aInnerClipRadii);
ColorPattern black(DeviceColor::MaskOpaqueBlack());
minDrawTarget->Fill(maskPath, black);
// Blur and fill in with the color we actually wanted
RefPtr<SourceSurface> minInsetBlur = DoBlur(&aShadowColor);
if (!minInsetBlur) {
return nullptr;
}
if (RefPtr<SourceSurface> opt =
aDestDrawTarget->OptimizeSourceSurface(minInsetBlur)) {
minInsetBlur = opt;
}
if (!aIsDestRect) {
CacheInsetBlur(outerSize, whitespaceSize, aBlurRadius, aInnerClipRadii,
aShadowColor, aDestDrawTarget->GetBackendType(),
minInsetBlur);
}
return minInsetBlur.forget();
}
/***
* We create our minimal rect with 2 rects.
* The first is the inside whitespace rect, that is "cut out"
* from the box. This is (1). This must be the size
* of the blur radius + corner radius so we can have a big enough
* inside cut.
*
* The second (2) is one blur radius surrounding the inner
* frame of (1). This is the amount of blur space required
* to get a proper blend.
*
* B = one blur size
* W = one blur + corner radii - known as inner margin
* ___________________________________
* | |
* | | | |
* | (2) | (1) | (2) |
* | B | W | B |
* | | | |
* | | | |
* | | |
* |________________________________|
*/
static void GetBlurMargins(const RectCornerRadii* aInnerClipRadii,
const IntSize& aBlurRadius, Margin& aOutBlurMargin,
Margin& aOutInnerMargin) {
Size cornerSize(0, 0);
if (aInnerClipRadii) {
const RectCornerRadii& corners = *aInnerClipRadii;
for (const auto i : mozilla::AllPhysicalCorners()) {
cornerSize.width = std::max(cornerSize.width, corners[i].width);
cornerSize.height = std::max(cornerSize.height, corners[i].height);
}
}
// Only the inside whitespace size cares about the border radius size.
// Outer sizes only care about blur.
IntSize margin = IntSize::Ceil(cornerSize) + aBlurRadius;
aOutInnerMargin.SizeTo(margin.height, margin.width, margin.height,
margin.width);
aOutBlurMargin.SizeTo(aBlurRadius.height, aBlurRadius.width,
aBlurRadius.height, aBlurRadius.width);
}
static bool GetInsetBoxShadowRects(const Margin& aBlurMargin,
const Margin& aInnerMargin,
const Rect& aShadowClipRect,
const Rect& aDestinationRect,
Rect& aOutWhitespaceRect,
Rect& aOutOuterRect) {
// We always copy (2 * blur radius) + corner radius worth of data to the
// destination rect This covers the blend of the path + the actual blur Need
// +1 so that we copy the edges correctly as we'll copy over the min box
// shadow corners then the +1 for the edges between Note, the (x,y)
// coordinates are from the blur margin since the frame outside the whitespace
// rect is 1 blur radius extra space.
Rect insideWhiteSpace(aBlurMargin.left, aBlurMargin.top,
aInnerMargin.LeftRight() + 1,
aInnerMargin.TopBottom() + 1);
// If the inner white space rect is larger than the shadow clip rect
// our approach does not work as we'll just copy one corner
// and cover the destination. In those cases, fallback to the destination rect
bool useDestRect = (aShadowClipRect.Width() <= aInnerMargin.LeftRight()) ||
(aShadowClipRect.Height() <= aInnerMargin.TopBottom());
if (useDestRect) {
aOutWhitespaceRect = aShadowClipRect;
aOutOuterRect = aDestinationRect;
} else {
aOutWhitespaceRect = insideWhiteSpace;
aOutOuterRect = aOutWhitespaceRect;
aOutOuterRect.Inflate(aBlurMargin);
}
return useDestRect;
}
void gfxAlphaBoxBlur::BlurInsetBox(
gfxContext* aDestinationCtx, const Rect& aDestinationRect,
const Rect& aShadowClipRect, const IntSize& aBlurRadius,
const sRGBColor& aShadowColor, const RectCornerRadii* aInnerClipRadii,
const Rect& aSkipRect, const Point& aShadowOffset) {
if ((aBlurRadius.width == 0 && aBlurRadius.height == 0) ||
aShadowClipRect.IsEmpty()) {
FillDestinationPath(aDestinationCtx, aDestinationRect, aShadowClipRect,
aShadowColor, aInnerClipRadii);
return;
}
DrawTarget* destDrawTarget = aDestinationCtx->GetDrawTarget();
Margin innerMargin;
Margin blurMargin;
GetBlurMargins(aInnerClipRadii, aBlurRadius, blurMargin, innerMargin);
Rect whitespaceRect;
Rect outerRect;
bool useDestRect =
GetInsetBoxShadowRects(blurMargin, innerMargin, aShadowClipRect,
aDestinationRect, whitespaceRect, outerRect);
// Check that the inset margin between the outer and whitespace rects is
// symmetric, and that all corner radii are the same, in which case the blur
// can be mirrored.
Margin checkMargin = outerRect - whitespaceRect;
bool mirrorCorners = checkMargin.left == checkMargin.right &&
checkMargin.top == checkMargin.bottom &&
(!aInnerClipRadii || aInnerClipRadii->AreRadiiSame());
RefPtr<SourceSurface> minBlur =
GetInsetBlur(outerRect, whitespaceRect, useDestRect, aShadowColor,
aBlurRadius, aInnerClipRadii, destDrawTarget, mirrorCorners);
if (!minBlur) {
return;
}
if (useDestRect) {
Rect destBlur = aDestinationRect;
destBlur.Inflate(blurMargin);
if (mirrorCorners) {
DrawMirroredBoxShadow(destDrawTarget, minBlur.get(), destBlur);
} else {
Rect srcBlur(Point(0, 0), Size(minBlur->GetSize()));
MOZ_ASSERT(RoundedOut(srcBlur).Size() == RoundedOut(destBlur).Size());
destDrawTarget->DrawSurface(minBlur, destBlur, srcBlur);
}
} else {
Rect srcOuter(outerRect);
Rect srcInner(srcOuter);
srcInner.Deflate(blurMargin); // The outer color fill
srcInner.Deflate(innerMargin); // The inner whitespace
// The shadow clip rect already takes into account the spread radius
Rect outerFillRect(aShadowClipRect);
outerFillRect.Inflate(blurMargin);
FillDestinationPath(aDestinationCtx, aDestinationRect, outerFillRect,
aShadowColor);
// Inflate once for the frame around the whitespace
Rect destRect(aShadowClipRect);
destRect.Inflate(blurMargin);
// Deflate for the blurred in white space
Rect destInnerRect(aShadowClipRect);
destInnerRect.Deflate(innerMargin);
if (mirrorCorners) {
DrawMirroredMinBoxShadow(destDrawTarget, minBlur, destRect, destInnerRect,
srcOuter, srcInner, aSkipRect);
} else {
DrawMinBoxShadow(destDrawTarget, minBlur, destRect, destInnerRect,
srcOuter, srcInner, aSkipRect);
}
}
}