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Diffstat (limited to 'samplecode/SampleDither.cpp')
| -rw-r--r-- | samplecode/SampleDither.cpp | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/samplecode/SampleDither.cpp b/samplecode/SampleDither.cpp new file mode 100644 index 0000000..64af007 --- /dev/null +++ b/samplecode/SampleDither.cpp @@ -0,0 +1,197 @@ +#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" + +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 }; + SkShader* s = SkGradientShader::CreateSweep(r.centerX(), r.centerY(), + colors, NULL, SK_ARRAY_COUNT(colors)); + p.setShader(s)->unref(); + + SkAutoCanvasRestore acr(c, true); + + c->translate(r.centerX(), r.centerY()); + c->rotate(angle); + c->translate(-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 = SkFloatToScalar(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->setConfig(SkBitmap::kARGB_8888_Config, 100, 100); + bm->allocPixels(); +#if 0 + bm->eraseColor(SK_ColorBLUE); + return; +#else + bm->eraseColor(0); +#endif + + SkCanvas c(*bm); + draw_sweep(&c, bm->width(), bm->height(), 0); +} + +static void pre_dither(const SkBitmap& bm) +{ + SkAutoLockPixels alp(bm); + + for (unsigned y = 0; y < bm.height(); y++) { + DITHER_4444_SCAN(y); + + SkPMColor* p = bm.getAddr32(0, y); + for (unsigned 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 SkView { +public: + SkBitmap fBM, fBMPreDither, fBM16; + SkScalar fAngle; + + DitherView() { + make_bm(&fBM); + make_bm(&fBMPreDither); + pre_dither(fBMPreDither); + fBM.copyTo(&fBM16, SkBitmap::kARGB_4444_Config); + + fAngle = 0; + } + +protected: + // overrides from SkEventSink + virtual bool onQuery(SkEvent* evt) { + if (SampleCode::TitleQ(*evt)) { + SampleCode::TitleR(evt, "Dither"); + return true; + } + return this->INHERITED::onQuery(evt); + } + + void drawBG(SkCanvas* canvas) { +// canvas->drawColor(0xFFDDDDDD); + canvas->drawColor(0xFF181818); + } + + virtual void onDraw(SkCanvas* canvas) { + this->drawBG(canvas); + + 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; + this->inval(NULL); + } + + virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y) + { + // fSweep += SK_Scalar1; + this->inval(NULL); + return this->INHERITED::onFindClickHandler(x, y); + } + + virtual bool onClick(Click* click) + { + return this->INHERITED::onClick(click); + } + +private: + typedef SkView INHERITED; +}; + +////////////////////////////////////////////////////////////////////////////// + +static SkView* MyFactory() { return new DitherView; } +static SkViewRegister reg(MyFactory); + |