/* * Copyright 2017 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #ifndef SkRasterClipStack_DEFINED #define SkRasterClipStack_DEFINED #include "include/core/SkClipOp.h" #include "include/core/SkDeque.h" #include "src/core/SkRasterClip.h" #include template class SkTStack { public: SkTStack(void* storage, size_t size) : fDeque(sizeof(T), storage, size), fTop(nullptr) {} ~SkTStack() { while (!fDeque.empty()) { ((T*)fDeque.back())->~T(); fDeque.pop_back(); } } bool empty() const { return fDeque.empty(); } int count() const { return fDeque.count(); } const T& top() const { SkASSERT(fTop); return *fTop; } T& top() { SkASSERT(fTop); return *fTop; } T* push_raw() { return (T*)fDeque.push_back(); } T& push() { fTop = this->push_raw(); new (fTop) T(); return *fTop; } T& push(const T& src) { fTop = this->push_raw(); new (fTop) T(src); return *fTop; } void pop() { fTop->~T(); fDeque.pop_back(); fTop = fDeque.empty() ? nullptr : (T*)fDeque.back(); } private: SkDeque fDeque; T* fTop; }; class SkRasterClipStack : SkNoncopyable { int fCounter = 0; public: SkRasterClipStack(int width, int height) : fStack(fStorage, sizeof(fStorage)) , fRootBounds(SkIRect::MakeWH(width, height)) { Rec& rec = fStack.push(); rec.fRC.setRect(fRootBounds); rec.fDeferredCount = 0; SkASSERT(fStack.count() == 1); } void setNewSize(int w, int h) { fRootBounds.setXYWH(0, 0, w, h); SkASSERT(fStack.count() == 1); Rec& rec = fStack.top(); SkASSERT(rec.fDeferredCount == 0); rec.fRC.setRect(fRootBounds); } const SkRasterClip& rc() const { return fStack.top().fRC; } void save() { fCounter += 1; SkASSERT(fStack.top().fDeferredCount >= 0); fStack.top().fDeferredCount += 1; } void restore() { fCounter -= 1; SkASSERT(fCounter >= 0); if (--fStack.top().fDeferredCount < 0) { SkASSERT(fStack.top().fDeferredCount == -1); SkASSERT(fStack.count() > 1); fStack.pop(); } } void clipRect(const SkMatrix& ctm, const SkRect& rect, SkClipOp op, bool aa) { this->writable_rc().op(rect, ctm, fRootBounds, (SkRegion::Op)op, aa); this->trimIfExpanding(op); this->validate(); } void clipRRect(const SkMatrix& ctm, const SkRRect& rrect, SkClipOp op, bool aa) { this->writable_rc().op(rrect, ctm, fRootBounds, (SkRegion::Op)op, aa); this->trimIfExpanding(op); this->validate(); } void clipPath(const SkMatrix& ctm, const SkPath& path, SkClipOp op, bool aa) { this->writable_rc().op(path, ctm, fRootBounds, (SkRegion::Op)op, aa); this->trimIfExpanding(op); this->validate(); } void clipRegion(const SkRegion& rgn, SkClipOp op) { this->writable_rc().op(rgn, (SkRegion::Op)op); this->trimIfExpanding(op); this->validate(); } void setDeviceClipRestriction(SkIRect* mutableClipRestriction) { this->writable_rc().setDeviceClipRestriction(mutableClipRestriction); } void validate() const { #ifdef SK_DEBUG const SkRasterClip& clip = this->rc(); if (fRootBounds.isEmpty()) { SkASSERT(clip.isEmpty()); } else if (!clip.isEmpty()) { SkASSERT(fRootBounds.contains(clip.getBounds())); } #endif } private: struct Rec { SkRasterClip fRC; int fDeferredCount; // 0 for a "normal" entry }; enum { ELEM_COUNT = 16, PTR_COUNT = ELEM_COUNT * sizeof(Rec) / sizeof(void*) }; void* fStorage[PTR_COUNT]; SkTStack fStack; SkIRect fRootBounds; SkRasterClip& writable_rc() { SkASSERT(fStack.top().fDeferredCount >= 0); if (fStack.top().fDeferredCount > 0) { fStack.top().fDeferredCount -= 1; fStack.push(fStack.top()); fStack.top().fDeferredCount = 0; } return fStack.top().fRC; } void trimIfExpanding(SkClipOp op) { if ((int)op > (int)SkClipOp::kIntersect) { Rec& rec = fStack.top(); SkASSERT(rec.fDeferredCount == 0); rec.fRC.op(fRootBounds, SkRegion::kIntersect_Op); } } }; #endif