src/third_party/skia/src/effects/SkTileImageFilter.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 "SkTileImageFilter.h"
   9 #include "SkBitmap.h"
  10 #include "SkCanvas.h"
  11 #include "SkDevice.h"
  12 #include "SkReadBuffer.h"
  13 #include "SkWriteBuffer.h"
  14 #include "SkMatrix.h"
  15 #include "SkPaint.h"
  16 #include "SkShader.h"
  17 #include "SkValidationUtils.h"
  18
  19 SkTileImageFilter* SkTileImageFilter::Create(const SkRect& srcRect, const SkRect& dstRect,
  20                                              SkImageFilter* input, uint32_t uniqueID) {
  21     if (!SkIsValidRect(srcRect) || !SkIsValidRect(dstRect)) {
  22         return NULL;
  23     }
  24     return SkNEW_ARGS(SkTileImageFilter, (srcRect, dstRect, input, uniqueID));
  25 }
  26
  27 bool SkTileImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src,
  28                                       const Context& ctx,
  29                                       SkBitmap* dst, SkIPoint* offset) const {
  30     SkBitmap source = src;
  31     SkImageFilter* input = getInput(0);
  32     SkIPoint srcOffset = SkIPoint::Make(0, 0);
  33     if (input && !input->filterImage(proxy, src, ctx, &source, &srcOffset)) {
  34         return false;
  35     }
  36
  37     SkRect dstRect;
  38     ctx.ctm().mapRect(&dstRect, fDstRect);
  39     SkIRect dstIRect;
  40     dstRect.roundOut(&dstIRect);
  41     int w = dstIRect.width();
  42     int h = dstIRect.height();
  43     if (!fSrcRect.width() || !fSrcRect.height() || !w || !h) {
  44         return false;
  45     }
  46
  47     SkRect srcRect;
  48     ctx.ctm().mapRect(&srcRect, fSrcRect);
  49     SkIRect srcIRect;
  50     srcRect.roundOut(&srcIRect);
  51     srcIRect.offset(-srcOffset);
  52     SkBitmap subset;
  53     SkIRect bounds;
  54     source.getBounds(&bounds);
  55
  56     if (!srcIRect.intersect(bounds)) {
  57         offset->fX = offset->fY = 0;
  58         return true;
  59     } else if (!source.extractSubset(&subset, srcIRect)) {
  60         return false;
  61     }
  62
  63     SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(w, h));
  64     if (NULL == device.get()) {
  65         return false;
  66     }
  67     SkCanvas canvas(device);
  68     SkPaint paint;
  69     paint.setXfermodeMode(SkXfermode::kSrc_Mode);
  70
  71     SkMatrix shaderMatrix;
  72     shaderMatrix.setTranslate(SkIntToScalar(srcOffset.fX),
  73                               SkIntToScalar(srcOffset.fY));
  74     SkAutoTUnref<SkShader> shader(SkShader::CreateBitmapShader(subset,
  75                                   SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode,
  76                                   &shaderMatrix));
  77     paint.setShader(shader);
  78     canvas.translate(-dstRect.fLeft, -dstRect.fTop);
  79     canvas.drawRect(dstRect, paint);
  80     *dst = device->accessBitmap(false);
  81     offset->fX = dstIRect.fLeft;
  82     offset->fY = dstIRect.fTop;
  83     return true;
  84 }
  85
  86 bool SkTileImageFilter::onFilterBounds(const SkIRect& src, const SkMatrix& ctm,
  87                                        SkIRect* dst) const {
  88     SkRect srcRect;
  89     ctm.mapRect(&srcRect, fSrcRect);
  90     SkIRect srcIRect;
  91     srcRect.roundOut(&srcIRect);
  92     srcIRect.join(src);
  93     *dst = srcIRect;
  94     return true;
  95 }
  96
  97 #ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
  98 SkTileImageFilter::SkTileImageFilter(SkReadBuffer& buffer)
  99   : INHERITED(1, buffer) {
 100     buffer.readRect(&fSrcRect);
 101     buffer.readRect(&fDstRect);
 102     buffer.validate(buffer.isValid() && SkIsValidRect(fSrcRect) && SkIsValidRect(fDstRect));
 103 }
 104 #endif
 105
 106 SkFlattenable* SkTileImageFilter::CreateProc(SkReadBuffer& buffer) {
 107     SK_IMAGEFILTER_UNFLATTEN_COMMON(common, 1);
 108     SkRect src, dst;
 109     buffer.readRect(&src);
 110     buffer.readRect(&dst);
 111     return Create(src, dst, common.getInput(0), common.uniqueID());
 112 }
 113
 114 void SkTileImageFilter::flatten(SkWriteBuffer& buffer) const {
 115     this->INHERITED::flatten(buffer);
 116     buffer.writeRect(fSrcRect);
 117     buffer.writeRect(fDstRect);
 118 }