skia2/gm/clippedbitmapshaders.cpp

129 lines
3.9 KiB
C++

/*
* Copyright 2013 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 "SkBitmap.h"
#include "SkCanvas.h"
#include "SkColor.h"
#include "SkShader.h"
namespace skiagm {
// This GM draws a 3x3 grid (with the center element excluded) of rectangles
// filled with a bitmap shader. The bitmap shader is transformed so that the
// pattern cell is at the center (excluded) region.
//
// In Repeat and Mirror mode, this tests that the bitmap shader still draws
// even though the pattern cell is outside the clip.
//
// In Clamp mode, this tests that the clamp is handled properly. For PDF,
// (and possibly other exported formats) this also "tests" that the image itself
// is not stored (well, you'll need to open it up with an external tool to
// verify that).
static SkBitmap create_bitmap() {
SkBitmap bmp;
bmp.allocN32Pixels(2, 2);
uint32_t* pixels = reinterpret_cast<uint32_t*>(bmp.getPixels());
pixels[0] = SkPreMultiplyColor(SK_ColorRED);
pixels[1] = SkPreMultiplyColor(SK_ColorGREEN);
pixels[2] = SkPreMultiplyColor(SK_ColorBLACK);
pixels[3] = SkPreMultiplyColor(SK_ColorBLUE);
return bmp;
}
static const SkScalar RECT_SIZE = 64;
static const SkScalar SLIDE_SIZE = 300;
class ClippedBitmapShadersGM : public GM {
public:
ClippedBitmapShadersGM(SkShader::TileMode mode, bool hq=false)
: fMode(mode), fHQ(hq) {
}
protected:
SkShader::TileMode fMode;
bool fHQ;
virtual SkString onShortName() {
SkString descriptor;
switch (fMode) {
case SkShader::kRepeat_TileMode:
descriptor = "tile";
break;
case SkShader::kMirror_TileMode:
descriptor = "mirror";
break;
case SkShader::kClamp_TileMode:
descriptor = "clamp";
break;
default:
SkASSERT(false);
}
descriptor.prepend("clipped-bitmap-shaders-");
if (fHQ) {
descriptor.append("-hq");
}
return descriptor;
}
virtual SkISize onISize() {
return SkISize::Make(300, 300);
}
virtual void onDraw(SkCanvas* canvas) {
SkBitmap bmp = create_bitmap();
SkMatrix s;
s.reset();
s.setScale(8, 8);
s.postTranslate(SLIDE_SIZE / 2, SLIDE_SIZE / 2);
SkShader* shader = SkShader::CreateBitmapShader(
bmp, fMode, fMode, &s);
SkPaint paint;
paint.setShader(shader)->unref();
if (fHQ) {
paint.setFilterQuality(kHigh_SkFilterQuality);
}
SkScalar margin = (SLIDE_SIZE / 3 - RECT_SIZE) / 2;
for (int i = 0; i < 3; i++) {
SkScalar yOrigin = SLIDE_SIZE / 3 * i + margin;
for (int j = 0; j < 3; j++) {
SkScalar xOrigin = SLIDE_SIZE / 3 * j + margin;
if (i == 1 && j == 1) {
continue; // skip center element
}
SkRect rect = SkRect::MakeXYWH(xOrigin, yOrigin,
RECT_SIZE, RECT_SIZE);
canvas->save();
canvas->clipRect(rect);
canvas->drawRect(rect, paint);
canvas->restore();
}
}
}
private:
typedef GM INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
DEF_GM( return new ClippedBitmapShadersGM(SkShader::kRepeat_TileMode); )
DEF_GM( return new ClippedBitmapShadersGM(SkShader::kMirror_TileMode); )
DEF_GM( return new ClippedBitmapShadersGM(SkShader::kClamp_TileMode); )
DEF_GM( return new ClippedBitmapShadersGM(SkShader::kRepeat_TileMode, true); )
DEF_GM( return new ClippedBitmapShadersGM(SkShader::kMirror_TileMode, true); )
DEF_GM( return new ClippedBitmapShadersGM(SkShader::kClamp_TileMode, true); )
}