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/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SampleCode.h"
#include "SkView.h"
#include "SkCanvas.h"
#include "SkGradientShader.h"
#include "SkPath.h"
#include "SkRegion.h"
#include "SkShader.h"
#include "SkUtils.h"
#include "Sk1DPathEffect.h"
#include "SkCornerPathEffect.h"
#include "SkPathMeasure.h"
#include "SkRandom.h"
#include "SkColorPriv.h"
#include "SkColorFilter.h"
#include "SkDither.h"
#include "sk_tool_utils.h"
static void draw_sweep(SkCanvas* c, int width, int height, SkScalar angle) {
SkRect r;
SkPaint p;
p.setAntiAlias(true);
// p.setDither(true);
p.setStrokeWidth(SkIntToScalar(width/10));
p.setStyle(SkPaint::kStroke_Style);
r.set(0, 0, SkIntToScalar(width), SkIntToScalar(height));
// SkColor colors[] = { SK_ColorRED, SK_ColorBLUE, SK_ColorGREEN, SK_ColorCYAN };
SkColor colors[] = { 0x4c737373, 0x4c737373, 0xffffd300 };
p.setShader(SkGradientShader::MakeSweep(r.centerX(), r.centerY(),
colors, nullptr, SK_ARRAY_COUNT(colors)));
SkAutoCanvasRestore acr(c, true);
c->rotate(angle, r.centerX(), r.centerY());
SkRect bounds = r;
r.inset(p.getStrokeWidth(), p.getStrokeWidth());
SkRect innerBounds = r;
if (true) {
c->drawOval(r, p);
} else {
SkScalar x = r.centerX();
SkScalar y = r.centerY();
SkScalar radius = r.width() / 2;
SkScalar thickness = p.getStrokeWidth();
SkScalar sweep = 360.0f;
SkPath path;
path.moveTo(x + radius, y);
// outer top
path.lineTo(x + radius + thickness, y);
// outer arc
path.arcTo(bounds, 0, sweep, false);
// inner arc
path.arcTo(innerBounds, sweep, -sweep, false);
path.close();
}
}
static void make_bm(SkBitmap* bm) {
bm->allocN32Pixels(100, 100);
bm->eraseColor(SK_ColorTRANSPARENT);
SkCanvas c(*bm);
draw_sweep(&c, bm->width(), bm->height(), 0);
}
static void pre_dither(const SkBitmap& bm) {
for (int y = 0; y < bm.height(); y++) {
DITHER_4444_SCAN(y);
SkPMColor* p = bm.getAddr32(0, y);
for (int x = 0; x < bm.width(); x++) {
SkPMColor c = *p;
unsigned a = SkGetPackedA32(c);
unsigned r = SkGetPackedR32(c);
unsigned g = SkGetPackedG32(c);
unsigned b = SkGetPackedB32(c);
unsigned d = DITHER_VALUE(x);
a = SkDITHER_A32To4444(a, d);
r = SkDITHER_R32To4444(r, d);
g = SkDITHER_G32To4444(g, d);
b = SkDITHER_B32To4444(b, d);
a = SkA4444ToA32(a);
r = SkR4444ToR32(r);
g = SkG4444ToG32(g);
b = SkB4444ToB32(b);
*p++ = SkPackARGB32(a, r, g, b);
}
}
}
class DitherView : public SampleView {
public:
SkBitmap fBM, fBMPreDither, fBM16;
SkScalar fAngle;
protected:
void onOnceBeforeDraw() override {
make_bm(&fBM);
make_bm(&fBMPreDither);
pre_dither(fBMPreDither);
sk_tool_utils::copy_to(&fBM16, kARGB_4444_SkColorType, fBM);
fAngle = 0;
this->setBGColor(0xFF181818);
}
// overrides from SkEventSink
bool onQuery(SkEvent* evt) override {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "Dither");
return true;
}
return this->INHERITED::onQuery(evt);
}
void onDrawContent(SkCanvas* canvas) override {
SkPaint paint;
SkScalar x = SkIntToScalar(10);
SkScalar y = SkIntToScalar(10);
const SkScalar DX = SkIntToScalar(fBM.width() + 10);
paint.setAntiAlias(true);
if (true) {
canvas->drawBitmap(fBM, x, y, &paint);
x += DX;
paint.setDither(true);
canvas->drawBitmap(fBM, x, y, &paint);
x += DX;
paint.setDither(false);
canvas->drawBitmap(fBMPreDither, x, y, &paint);
x += DX;
canvas->drawBitmap(fBM16, x, y, &paint);
}
canvas->translate(DX, DX*2);
draw_sweep(canvas, fBM.width(), fBM.height(), fAngle);
canvas->translate(DX, 0);
draw_sweep(canvas, fBM.width()>>1, fBM.height()>>1, fAngle);
canvas->translate(DX, 0);
draw_sweep(canvas, fBM.width()>>2, fBM.height()>>2, fAngle);
fAngle += SK_Scalar1/2;
}
private:
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new DitherView; }
static SkViewRegister reg(MyFactory);
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