michael@0: /*
michael@0:  * Copyright 2013 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #include "SkDrawLooper.h"
michael@0: #include "SkCanvas.h"
michael@0: #include "SkMatrix.h"
michael@0: #include "SkPaint.h"
michael@0: #include "SkRect.h"
michael@0: #include "SkSmallAllocator.h"
michael@0: 
michael@0: bool SkDrawLooper::canComputeFastBounds(const SkPaint& paint) const {
michael@0:     SkCanvas canvas;
michael@0:     SkSmallAllocator<1, 32> allocator;
michael@0:     void* buffer = allocator.reserveT<SkDrawLooper::Context>(this->contextSize());
michael@0: 
michael@0:     SkDrawLooper::Context* context = this->createContext(&canvas, buffer);
michael@0:     for (;;) {
michael@0:         SkPaint p(paint);
michael@0:         if (context->next(&canvas, &p)) {
michael@0:             p.setLooper(NULL);
michael@0:             if (!p.canComputeFastBounds()) {
michael@0:                 return false;
michael@0:             }
michael@0:         } else {
michael@0:             break;
michael@0:         }
michael@0:     }
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: void SkDrawLooper::computeFastBounds(const SkPaint& paint, const SkRect& src,
michael@0:                                      SkRect* dst) const {
michael@0:     SkCanvas canvas;
michael@0:     SkSmallAllocator<1, 32> allocator;
michael@0:     void* buffer = allocator.reserveT<SkDrawLooper::Context>(this->contextSize());
michael@0: 
michael@0:     *dst = src;   // catch case where there are no loops
michael@0:     SkDrawLooper::Context* context = this->createContext(&canvas, buffer);
michael@0:     for (bool firstTime = true;; firstTime = false) {
michael@0:         SkPaint p(paint);
michael@0:         if (context->next(&canvas, &p)) {
michael@0:             SkRect r(src);
michael@0: 
michael@0:             p.setLooper(NULL);
michael@0:             p.computeFastBounds(r, &r);
michael@0:             canvas.getTotalMatrix().mapRect(&r);
michael@0: 
michael@0:             if (firstTime) {
michael@0:                 *dst = r;
michael@0:             } else {
michael@0:                 dst->join(r);
michael@0:             }
michael@0:         } else {
michael@0:             break;
michael@0:         }
michael@0:     }
michael@0: }