src/third_party/skia/src/effects/SkRectShaderImageFilter.cpp

   1 /*
   2  * Copyright 2013 Google Inc.
   3  *
   4  * Use of this source code is governed by a BSD-style license that can be
   5  * found in the LICENSE file.
   6  */
   7
   8 #include "SkRectShaderImageFilter.h"
   9 #include "SkBitmap.h"
  10 #include "SkCanvas.h"
  11 #include "SkDevice.h"
  12 #include "SkReadBuffer.h"
  13 #include "SkWriteBuffer.h"
  14 #include "SkShader.h"
  15
  16 SkRectShaderImageFilter* SkRectShaderImageFilter::Create(SkShader* s, const SkRect& rect) {
  17     SkASSERT(s);
  18     uint32_t flags = CropRect::kHasAll_CropEdge;
  19     if (rect.width() == 0 || rect.height() == 0) {
  20         flags = 0x0;
  21     }
  22     CropRect cropRect(rect, flags);
  23     return SkNEW_ARGS(SkRectShaderImageFilter, (s, &cropRect));
  24 }
  25
  26 SkRectShaderImageFilter* SkRectShaderImageFilter::Create(SkShader* s, const CropRect* cropRect) {
  27     SkASSERT(s);
  28     return SkNEW_ARGS(SkRectShaderImageFilter, (s, cropRect));
  29 }
  30
  31 SkRectShaderImageFilter::SkRectShaderImageFilter(SkShader* s, const CropRect* cropRect)
  32   : INHERITED(0, NULL, cropRect)
  33   , fShader(s) {
  34     SkASSERT(s);
  35     s->ref();
  36 }
  37
  38 SkRectShaderImageFilter::SkRectShaderImageFilter(SkReadBuffer& buffer)
  39   : INHERITED(0, buffer) {
  40     fShader = buffer.readShader();
  41 }
  42
  43 void SkRectShaderImageFilter::flatten(SkWriteBuffer& buffer) const {
  44     this->INHERITED::flatten(buffer);
  45
  46     buffer.writeFlattenable(fShader);
  47 }
  48
  49 SkRectShaderImageFilter::~SkRectShaderImageFilter() {
  50     SkSafeUnref(fShader);
  51 }
  52
  53 bool SkRectShaderImageFilter::onFilterImage(Proxy* proxy,
  54                                             const SkBitmap& source,
  55                                             const Context& ctx,
  56                                             SkBitmap* result,
  57                                             SkIPoint* offset) const {
  58     SkIRect bounds;
  59     if (!this->applyCropRect(ctx, source, SkIPoint::Make(0, 0), &bounds)) {
  60         return false;
  61     }
  62
  63     SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(bounds.width(),
  64                                                           bounds.height()));
  65     if (NULL == device.get()) {
  66         return false;
  67     }
  68     SkCanvas canvas(device.get());
  69
  70     SkPaint paint;
  71     SkMatrix matrix(ctx.ctm());
  72     matrix.postTranslate(SkIntToScalar(-bounds.left()), SkIntToScalar(-bounds.top()));
  73     paint.setShader(SkShader::CreateLocalMatrixShader(fShader, matrix))->unref();
  74
  75     SkRect rect = SkRect::MakeWH(SkIntToScalar(bounds.width()), SkIntToScalar(bounds.height()));
  76     canvas.drawRect(rect, paint);
  77
  78     *result = device.get()->accessBitmap(false);
  79     offset->fX = bounds.fLeft;
  80     offset->fY = bounds.fTop;
  81     return true;
  82 }