skia2/gm/matrixconvolution.cpp
senorblanco@chromium.org 5faa2dc266 Implements a matrix convolution filter (raster path only). The filtering loop
is templated on the tiling mode for speed:  interior pixels are unconditionally
fetched; border pixels apply the appropriate tiling mode before fetching.  It
handles target, bias, divisor (as gain), and edge modes (named to be more
skia-like).  It does not handle the "preserveAlpha" semantics of
feConvolveMatrix, nor "kernelUnitLength".



git-svn-id: http://skia.googlecode.com/svn/trunk@5592 2bbb7eff-a529-9590-31e7-b0007b416f81
2012-09-18 20:32:34 +00:00

83 lines
2.6 KiB
C++

/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm.h"
#include "SkMatrixConvolutionImageFilter.h"
namespace skiagm {
class MatrixConvolutionGM : public GM {
public:
MatrixConvolutionGM() : fInitialized(false) {
this->setBGColor(0x00000000);
}
protected:
virtual SkString onShortName() {
return SkString("matrixconvolution");
}
void make_bitmap() {
fBitmap.setConfig(SkBitmap::kARGB_8888_Config, 80, 80);
fBitmap.allocPixels();
SkDevice device(fBitmap);
SkCanvas canvas(&device);
canvas.clear(0x00000000);
SkPaint paint;
paint.setAntiAlias(true);
paint.setColor(0xFFFFFFFF);
paint.setTextSize(SkIntToScalar(180));
const char* str = "e";
canvas.drawText(str, strlen(str), SkIntToScalar(-10), SkIntToScalar(80), paint);
}
virtual SkISize onISize() {
return make_isize(300, 300);
}
void draw(SkCanvas* canvas, int x, int y, const SkIPoint& target, SkMatrixConvolutionImageFilter::TileMode tileMode) {
SkScalar kernel[9] = {
SkIntToScalar( 1), SkIntToScalar( 1), SkIntToScalar( 1),
SkIntToScalar( 1), SkIntToScalar(-7), SkIntToScalar( 1),
SkIntToScalar( 1), SkIntToScalar( 1), SkIntToScalar( 1),
};
SkISize kernelSize = SkISize::Make(3, 3);
SkScalar gain = SkFloatToScalar(0.3f), bias = SkIntToScalar(100);
SkPaint paint;
SkAutoTUnref<SkImageFilter> filter(SkNEW_ARGS(SkMatrixConvolutionImageFilter, (kernelSize, kernel, gain, bias, target, tileMode)));
paint.setImageFilter(filter);
canvas->drawSprite(fBitmap, x, y, &paint);
}
virtual void onDraw(SkCanvas* canvas) {
if (!fInitialized) {
make_bitmap();
fInitialized = true;
}
canvas->clear(0x00000000);
SkIPoint target = SkIPoint::Make(1, 1);
for (target.fY = 0; target.fY < 3; ++target.fY) {
int y = target.fY * 100 + 10;
draw(canvas, 10, y, target, SkMatrixConvolutionImageFilter::kClamp_TileMode);
draw(canvas, 110, y, target, SkMatrixConvolutionImageFilter::kClampToBlack_TileMode);
draw(canvas, 210, y, target, SkMatrixConvolutionImageFilter::kRepeat_TileMode);
}
}
private:
typedef GM INHERITED;
SkBitmap fBitmap;
bool fInitialized;
};
//////////////////////////////////////////////////////////////////////////////
static GM* MyFactory(void*) { return new MatrixConvolutionGM; }
static GMRegistry reg(MyFactory);
}