/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- * 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 "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/UniquePtr.h" #include "mozilla/UniquePtrExtensions.h" #include "nsExpirationTracker.h" #include "nsClassHashtable.h" #include "gfxUtils.h" using namespace mozilla; using namespace mozilla::gfx; gfxAlphaBoxBlur::gfxAlphaBoxBlur() { } gfxAlphaBoxBlur::~gfxAlphaBoxBlur() { mContext = nullptr; } gfxContext* gfxAlphaBoxBlur::Init(const gfxRect& aRect, const IntSize& aSpreadRadius, const IntSize& aBlurRadius, const gfxRect* aDirtyRect, const gfxRect* aSkipRect) { mozilla::gfx::Rect rect(Float(aRect.x), Float(aRect.y), Float(aRect.width), Float(aRect.height)); IntSize spreadRadius(aSpreadRadius.width, aSpreadRadius.height); IntSize blurRadius(aBlurRadius.width, aBlurRadius.height); UniquePtr<Rect> dirtyRect; if (aDirtyRect) { dirtyRect = MakeUnique<Rect>(Float(aDirtyRect->x), Float(aDirtyRect->y), Float(aDirtyRect->width), Float(aDirtyRect->height)); } UniquePtr<Rect> skipRect; if (aSkipRect) { skipRect = MakeUnique<Rect>(Float(aSkipRect->x), Float(aSkipRect->y), Float(aSkipRect->width), Float(aSkipRect->height)); } mBlur = MakeUnique<AlphaBoxBlur>(rect, spreadRadius, blurRadius, dirtyRect.get(), skipRect.get()); size_t blurDataSize = mBlur->GetSurfaceAllocationSize(); if (blurDataSize == 0) return nullptr; IntSize size = mBlur->GetSize(); // Make an alpha-only surface to draw on. We will play with the data after // everything is drawn to create a blur effect. mData = MakeUniqueFallible<unsigned char[]>(blurDataSize); if (!mData) { return nullptr; } memset(mData.get(), 0, blurDataSize); RefPtr<DrawTarget> dt = gfxPlatform::CreateDrawTargetForData(mData.get(), size, mBlur->GetStride(), SurfaceFormat::A8); if (!dt || !dt->IsValid()) { return nullptr; } IntRect irect = mBlur->GetRect(); gfxPoint topleft(irect.TopLeft().x, irect.TopLeft().y); mContext = gfxContext::CreateOrNull(dt); MOZ_ASSERT(mContext); // already checked for target above mContext->SetMatrix(gfxMatrix::Translation(-topleft)); return mContext; } void DrawBlur(gfxContext* aDestinationCtx, SourceSurface* aBlur, const IntPoint& aTopLeft, const Rect* aDirtyRect) { DrawTarget *dest = aDestinationCtx->GetDrawTarget(); RefPtr<gfxPattern> thebesPat = aDestinationCtx->GetPattern(); Pattern* pat = thebesPat->GetPattern(dest, nullptr); Matrix oldTransform = dest->GetTransform(); Matrix newTransform = oldTransform; newTransform.PreTranslate(aTopLeft.x, aTopLeft.y); // Avoid a semi-expensive clip operation if we can, otherwise // clip to the dirty rect if (aDirtyRect) { dest->PushClipRect(*aDirtyRect); } dest->SetTransform(newTransform); dest->MaskSurface(*pat, aBlur, Point(0, 0)); dest->SetTransform(oldTransform); if (aDirtyRect) { dest->PopClip(); } } already_AddRefed<SourceSurface> gfxAlphaBoxBlur::DoBlur(DrawTarget* aDT, IntPoint* aTopLeft) { mBlur->Blur(mData.get()); *aTopLeft = mBlur->GetRect().TopLeft(); return aDT->CreateSourceSurfaceFromData(mData.get(), mBlur->GetSize(), mBlur->GetStride(), SurfaceFormat::A8); } void gfxAlphaBoxBlur::Paint(gfxContext* aDestinationCtx) { if (!mContext) return; DrawTarget *dest = aDestinationCtx->GetDrawTarget(); if (!dest) { NS_WARNING("Blurring not supported for Thebes contexts!"); return; } Rect* dirtyRect = mBlur->GetDirtyRect(); IntPoint topLeft; RefPtr<SourceSurface> mask = DoBlur(dest, &topLeft); if (!mask) { NS_ERROR("Failed to create mask!"); return; } DrawBlur(aDestinationCtx, mask, topLeft, dirtyRect); } 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; Color mShadowColor; BackendType mBackend; RectCornerRadii mCornerRadii; bool mIsInset; // Only used for inset blurs bool mHasBorderRadius; IntSize mInnerMinSize; BlurCacheKey(IntSize aMinSize, IntSize aBlurRadius, RectCornerRadii* aCornerRadii, const Color& aShadowColor, BackendType aBackendType) : BlurCacheKey(aMinSize, IntSize(0, 0), aBlurRadius, aCornerRadii, aShadowColor, false, 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) , mHasBorderRadius(aOther->mHasBorderRadius) , mInnerMinSize(aOther->mInnerMinSize) { } explicit BlurCacheKey(IntSize aOuterMinSize, IntSize aInnerMinSize, IntSize aBlurRadius, const RectCornerRadii* aCornerRadii, const Color& aShadowColor, bool aIsInset, bool aHasBorderRadius, BackendType aBackendType) : mMinSize(aOuterMinSize) , mBlurRadius(aBlurRadius) , mShadowColor(aShadowColor) , mBackend(aBackendType) , mCornerRadii(aCornerRadii ? *aCornerRadii : RectCornerRadii()) , mIsInset(aIsInset) , mHasBorderRadius(aHasBorderRadius) , mInnerMinSize(aInnerMinSize) { } 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); hash = AddToHash(hash, HashBytes(&aKey->mHasBorderRadius, sizeof(bool))); } 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 (mHasBorderRadius == aKey->mHasBorderRadius) && (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, IntMargin aExtendDestBy, const BlurCacheKey& aKey) : mBlur(aBlur) , mExtendDest(aExtendDestBy) , mKey(aKey) {} BlurCacheData(const BlurCacheData& aOther) : mBlur(aOther.mBlur) , mExtendDest(aOther.mExtendDest) , mKey(aOther.mKey) { } nsExpirationState *GetExpirationState() { return &mExpirationState; } nsExpirationState mExpirationState; RefPtr<SourceSurface> mBlur; IntMargin mExtendDest; 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) { RemoveObject(aObject); mHashEntries.Remove(aObject->mKey); } BlurCacheData* Lookup(const IntSize aMinSize, const IntSize& aBlurRadius, RectCornerRadii* aCornerRadii, const Color& 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 Color& aShadowColor, const bool& aHasBorderRadius, BackendType aBackendType) { bool insetBoxShadow = true; BlurCacheKey key(aOuterMinSize, aInnerMinSize, aBlurRadius, aCornerRadii, aShadowColor, insetBoxShadow, aHasBorderRadius, aBackendType); BlurCacheData* blur = mHashEntries.Get(key); if (blur) { MarkUsed(blur); } return blur; } // Returns true if we successfully register the blur in the cache, false // otherwise. bool RegisterEntry(BlurCacheData* aValue) { nsresult rv = AddObject(aValue); 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 things considering we are short on memory // anyway, we probably don't want to retain things. return false; } mHashEntries.Put(aValue->mKey, aValue); return true; } protected: static const uint32_t GENERATION_MS = 1000; /** * FIXME use nsTHashtable to avoid duplicating the BlurCacheKey. * https://bugzilla.mozilla.org/show_bug.cgi?id=761393#c47 */ nsClassHashtable<BlurCacheKey, BlurCacheData> mHashEntries; }; static BlurCache* gBlurCache = nullptr; static IntSize ComputeMinSizeForShadowShape(RectCornerRadii* aCornerRadii, IntSize aBlurRadius, IntMargin& aSlice, const IntSize& aRectSize) { float cornerWidth = 0; float cornerHeight = 0; if (aCornerRadii) { RectCornerRadii corners = *aCornerRadii; for (size_t i = 0; i < 4; i++) { cornerWidth = std::max(cornerWidth, corners[i].width); cornerHeight = std::max(cornerHeight, corners[i].height); } } aSlice = IntMargin(ceil(cornerHeight) + aBlurRadius.height, ceil(cornerWidth) + aBlurRadius.width, ceil(cornerHeight) + aBlurRadius.height, ceil(cornerWidth) + aBlurRadius.width); IntSize minSize(aSlice.LeftRight() + 1, aSlice.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; aSlice.left = 0; aSlice.right = 0; } if (aRectSize.height < minSize.height) { minSize.height = aRectSize.height; aSlice.top = 0; aSlice.bottom = 0; } MOZ_ASSERT(aSlice.LeftRight() <= minSize.width); MOZ_ASSERT(aSlice.TopBottom() <= minSize.height); return minSize; } void CacheBlur(DrawTarget& aDT, const IntSize& aMinSize, const IntSize& aBlurRadius, RectCornerRadii* aCornerRadii, const Color& aShadowColor, IntMargin aExtendDest, SourceSurface* aBoxShadow) { BlurCacheKey key(aMinSize, aBlurRadius, aCornerRadii, aShadowColor, aDT.GetBackendType()); BlurCacheData* data = new BlurCacheData(aBoxShadow, aExtendDest, key); if (!gBlurCache->RegisterEntry(data)) { delete data; } } // Blurs a small surface and creates the mask. static already_AddRefed<SourceSurface> CreateBlurMask(const IntSize& aMinSize, RectCornerRadii* aCornerRadii, IntSize aBlurRadius, IntMargin& aExtendDestBy, IntMargin& aSliceBorder, DrawTarget& aDestDrawTarget) { gfxAlphaBoxBlur blur; IntRect minRect(IntPoint(), aMinSize); gfxContext* blurCtx = blur.Init(ThebesRect(Rect(minRect)), IntSize(), aBlurRadius, nullptr, nullptr); if (!blurCtx) { return nullptr; } DrawTarget* blurDT = blurCtx->GetDrawTarget(); ColorPattern black(Color(0.f, 0.f, 0.f, 1.f)); if (aCornerRadii) { RefPtr<Path> roundedRect = MakePathForRoundedRect(*blurDT, Rect(minRect), *aCornerRadii); blurDT->Fill(roundedRect, black); } else { blurDT->FillRect(Rect(minRect), black); } IntPoint topLeft; RefPtr<SourceSurface> result = blur.DoBlur(&aDestDrawTarget, &topLeft); if (!result) { return nullptr; } IntRect expandedMinRect(topLeft, result->GetSize()); aExtendDestBy = expandedMinRect - minRect; aSliceBorder += aExtendDestBy; MOZ_ASSERT(aSliceBorder.LeftRight() <= expandedMinRect.width); MOZ_ASSERT(aSliceBorder.TopBottom() <= expandedMinRect.height); return result.forget(); } static already_AddRefed<SourceSurface> CreateBoxShadow(DrawTarget& aDestDT, SourceSurface* aBlurMask, const Color& aShadowColor) { IntSize blurredSize = aBlurMask->GetSize(); RefPtr<DrawTarget> boxShadowDT = Factory::CreateDrawTarget(aDestDT.GetBackendType(), blurredSize, SurfaceFormat::B8G8R8A8); if (!boxShadowDT) { return nullptr; } ColorPattern shadowColor(ToDeviceColor(aShadowColor)); boxShadowDT->MaskSurface(shadowColor, aBlurMask, Point(0, 0)); return boxShadowDT->Snapshot(); } static already_AddRefed<SourceSurface> GetBlur(gfxContext* aDestinationCtx, const IntSize& aRectSize, const IntSize& aBlurRadius, RectCornerRadii* aCornerRadii, const Color& aShadowColor, IntMargin& aExtendDestBy, IntMargin& aSlice) { if (!gBlurCache) { gBlurCache = new BlurCache(); } IntSize minSize = ComputeMinSizeForShadowShape(aCornerRadii, aBlurRadius, aSlice, 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. Matrix destMatrix = ToMatrix(aDestinationCtx->CurrentMatrix()); bool useDestRect = !destMatrix.IsRectilinear() || destMatrix.HasNonIntegerTranslation(); if (useDestRect) { minSize = aRectSize; } DrawTarget& destDT = *aDestinationCtx->GetDrawTarget(); BlurCacheData* cached = gBlurCache->Lookup(minSize, aBlurRadius, aCornerRadii, aShadowColor, destDT.GetBackendType()); if (cached && !useDestRect) { // See CreateBlurMask() for these values aExtendDestBy = cached->mExtendDest; aSlice = aSlice + aExtendDestBy; RefPtr<SourceSurface> blur = cached->mBlur; return blur.forget(); } RefPtr<SourceSurface> blurMask = CreateBlurMask(minSize, aCornerRadii, aBlurRadius, aExtendDestBy, aSlice, destDT); if (!blurMask) { return nullptr; } RefPtr<SourceSurface> boxShadow = CreateBoxShadow(destDT, blurMask, aShadowColor); if (!boxShadow) { return nullptr; } if (useDestRect) { // Since we're just going to paint the actual rect to the destination aSlice.SizeTo(0, 0, 0, 0); } else { CacheBlur(destDT, minSize, aBlurRadius, aCornerRadii, aShadowColor, aExtendDestBy, 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 void RepeatOrStretchSurface(DrawTarget& aDT, SourceSurface* aSurface, const Rect& aDest, const Rect& aSrc, Rect& aSkipRect) { if (aSkipRect.Contains(aDest)) { return; } if ((!aDT.GetTransform().IsRectilinear() && aDT.GetBackendType() != BackendType::CAIRO) || (aDT.GetBackendType() == BackendType::DIRECT2D1_1)) { // 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. // Calling FillRect on a D2D backend with a repeating pattern is much slower // than DrawSurface, so special case the D2D backend here. 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, Rect& aSkipRect) { if (aSkipRect.Contains(aDest)) { return; } aDT.DrawSurface(aSurface, aDest, aSrc); } static void DrawBoxShadows(DrawTarget& aDestDrawTarget, SourceSurface* aSourceBlur, Rect aDstOuter, Rect aDstInner, Rect aSrcOuter, Rect aSrcInner, Rect aSkipRect) { // 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); } /*** * 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, RectCornerRadii* aCornerRadii, const gfxPoint& aBlurStdDev, const Color& aShadowColor, const gfxRect& aDirtyRect, const gfxRect& aSkipRect) { IntSize blurRadius = CalculateBlurRadius(aBlurStdDev); IntRect rect = RoundedToInt(ToRect(aRect)); IntMargin extendDestBy; IntMargin slice; RefPtr<SourceSurface> boxShadow = GetBlur(aDestinationCtx, rect.Size(), blurRadius, aCornerRadii, aShadowColor, extendDestBy, slice); 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(), Size(boxShadow->GetSize())); Rect srcInner = srcOuter; srcInner.Deflate(Margin(slice)); rect.Inflate(extendDestBy); Rect dstOuter(rect); Rect dstInner(rect); dstInner.Deflate(Margin(slice)); Rect skipRect = ToRect(aSkipRect); if (srcInner.IsEqualInterior(srcOuter)) { MOZ_ASSERT(dstInner.IsEqualInterior(dstOuter)); // The target rect is smaller than the minimal size so just draw the surface destDrawTarget.DrawSurface(boxShadow, dstInner, srcInner); } else { DrawBoxShadows(destDrawTarget, boxShadow, dstOuter, dstInner, srcOuter, srcInner, skipRect); // Middle part RepeatOrStretchSurface(destDrawTarget, boxShadow, RectWithEdgesTRBL(dstInner.Y(), dstInner.XMost(), dstInner.YMost(), dstInner.X()), RectWithEdgesTRBL(srcInner.Y(), srcInner.XMost(), srcInner.YMost(), srcInner.X()), skipRect); } // 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 of 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". // On OS X there is an additional problem with turning off AA: CoreGraphics // will not just fill the pixels that have their pixel center inside the // filled shape. Instead, it will fill all the pixels which are partially // covered by the shape. So for pixels on the edge between two adjacent parts, // all those pixels will be painted to by both parts, which looks very bad. destDrawTarget.PopClip(); } static already_AddRefed<Path> GetBoxShadowInsetPath(DrawTarget* aDrawTarget, const Rect aOuterRect, const Rect aInnerRect, const bool aHasBorderRadius, 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 (aHasBorderRadius) { 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 Color& aShadowColor, const bool aHasBorderRadius, const RectCornerRadii& aInnerClipRadii) { // 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, aHasBorderRadius, aInnerClipRadii); aDestinationCtx->SetPath(shadowPath); aDestinationCtx->Fill(); } static void CacheInsetBlur(const IntSize aMinOuterSize, const IntSize aMinInnerSize, const IntSize& aBlurRadius, const RectCornerRadii* aCornerRadii, const Color& aShadowColor, const bool& aHasBorderRadius, BackendType aBackendType, SourceSurface* aBoxShadow) { bool isInsetBlur = true; BlurCacheKey key(aMinOuterSize, aMinInnerSize, aBlurRadius, aCornerRadii, aShadowColor, isInsetBlur, aHasBorderRadius, aBackendType); IntMargin extendDestBy(0, 0, 0, 0); BlurCacheData* data = new BlurCacheData(aBoxShadow, extendDestBy, key); if (!gBlurCache->RegisterEntry(data)) { delete data; } } already_AddRefed<mozilla::gfx::SourceSurface> gfxAlphaBoxBlur::GetInsetBlur(const mozilla::gfx::Rect aOuterRect, const mozilla::gfx::Rect aWhitespaceRect, const bool aIsDestRect, const mozilla::gfx::Color& aShadowColor, const mozilla::gfx::IntSize& aBlurRadius, const bool aHasBorderRadius, const RectCornerRadii& aInnerClipRadii, DrawTarget* aDestDrawTarget) { if (!gBlurCache) { gBlurCache = new BlurCache(); } IntSize outerSize((int)aOuterRect.width, (int)aOuterRect.height); IntSize whitespaceSize((int)aWhitespaceRect.width, (int)aWhitespaceRect.height); BlurCacheData* cached = gBlurCache->LookupInsetBoxShadow(outerSize, whitespaceSize, aBlurRadius, &aInnerClipRadii, aShadowColor, aHasBorderRadius, aDestDrawTarget->GetBackendType()); if (cached && !aIsDestRect) { // 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; IntSize zeroSpread(0, 0); gfxContext* minGfxContext = Init(ThebesRect(blurRect), zeroSpread, aBlurRadius, nullptr, nullptr); if (!minGfxContext) { return nullptr; } // This is really annoying. When we create the AlphaBoxBlur, the gfxContext // 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) { minGfxContext->SetMatrix(gfxMatrix()); } DrawTarget* minDrawTarget = minGfxContext->GetDrawTarget(); // Fill in the path between the inside white space / outer rects // NOT the inner frame RefPtr<Path> maskPath = GetBoxShadowInsetPath(minDrawTarget, aOuterRect, aWhitespaceRect, aHasBorderRadius, aInnerClipRadii); Color black(0.f, 0.f, 0.f, 1.f); minGfxContext->SetColor(black); minGfxContext->SetPath(maskPath); minGfxContext->Fill(); // Create the A8 mask IntPoint topLeft; RefPtr<SourceSurface> minMask = DoBlur(minDrawTarget, &topLeft); if (!minMask) { return nullptr; } // Fill in with the color we actually wanted RefPtr<SourceSurface> minInsetBlur = CreateBoxShadow(*aDestDrawTarget, minMask, aShadowColor); if (!minInsetBlur) { return nullptr; } if (!aIsDestRect) { CacheInsetBlur(outerSize, whitespaceSize, aBlurRadius, &aInnerClipRadii, aShadowColor, aHasBorderRadius, 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 bool aHasBorderRadius, const RectCornerRadii& aInnerClipRadii, const IntSize aBlurRadius, Margin& aOutBlurMargin, Margin& aOutInnerMargin) { float cornerWidth = 0; float cornerHeight = 0; if (aHasBorderRadius) { for (size_t i = 0; i < 4; i++) { cornerWidth = std::max(cornerWidth, aInnerClipRadii[i].width); cornerHeight = std::max(cornerHeight, aInnerClipRadii[i].height); } } // Only the inside whitespace size cares about the border radius size. // Outer sizes only care about blur. int width = cornerWidth + aBlurRadius.width; int height = cornerHeight + aBlurRadius.height; aOutInnerMargin.SizeTo(height, width, height, 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 IntSize aSpreadRadius, const Color& aShadowColor, bool aHasBorderRadius, const RectCornerRadii& aInnerClipRadii, const Rect aSkipRect, const Point aShadowOffset) { if ((aBlurRadius.width == 0 && aBlurRadius.height == 0) || aShadowClipRect.IsEmpty()) { FillDestinationPath(aDestinationCtx, aDestinationRect, aShadowClipRect, aShadowColor, aHasBorderRadius, aInnerClipRadii); return; } DrawTarget* destDrawTarget = aDestinationCtx->GetDrawTarget(); Margin innerMargin; Margin blurMargin; GetBlurMargins(aHasBorderRadius, aInnerClipRadii, aBlurRadius, blurMargin, innerMargin); Rect whitespaceRect; Rect outerRect; bool useDestRect = GetInsetBoxShadowRects(blurMargin, innerMargin, aShadowClipRect, aDestinationRect, whitespaceRect, outerRect); RefPtr<SourceSurface> minBlur = GetInsetBlur(outerRect, whitespaceRect, useDestRect, aShadowColor, aBlurRadius, aHasBorderRadius, aInnerClipRadii, destDrawTarget); if (!minBlur) { return; } if (useDestRect) { IntSize blurSize = minBlur->GetSize(); Rect srcBlur(0, 0, blurSize.width, blurSize.height); Rect destBlur = aDestinationRect; // The blur itself expands the rect by the blur margin, so we // have to mimic that here. destBlur.Inflate(blurMargin); MOZ_ASSERT(srcBlur.Size() == 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, false, RectCornerRadii()); // 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); DrawBoxShadows(*destDrawTarget, minBlur, destRect, destInnerRect, srcOuter, srcInner, aSkipRect); } }