reed@android.com | 113244f | 2009-08-31 21:04:24 +0000 | [diff] [blame] | 1 | #include "SampleCode.h" |
| 2 | #include "SkColorPriv.h" |
| 3 | #include "SkGradientShader.h" |
| 4 | #include "SkView.h" |
| 5 | #include "SkCanvas.h" |
| 6 | #include "SkUtils.h" |
| 7 | |
| 8 | static SkBitmap make_bitmap() { |
| 9 | SkBitmap bm; |
| 10 | SkColorTable* ctable = new SkColorTable(256); |
| 11 | |
| 12 | SkPMColor* c = ctable->lockColors(); |
| 13 | for (int i = 0; i < 256; i++) { |
| 14 | c[i] = SkPackARGB32(255 - i, 0, 0, 0); |
| 15 | } |
| 16 | ctable->unlockColors(true); |
| 17 | bm.setConfig(SkBitmap::kIndex8_Config, 256, 256); |
| 18 | bm.allocPixels(ctable); |
| 19 | ctable->unref(); |
| 20 | |
| 21 | bm.lockPixels(); |
| 22 | const float cx = bm.width() * 0.5f; |
| 23 | const float cy = bm.height() * 0.5f; |
| 24 | for (int y = 0; y < bm.height(); y++) { |
| 25 | float dy = y - cy; |
| 26 | dy *= dy; |
| 27 | uint8_t* p = bm.getAddr8(0, y); |
| 28 | for (int x = 0; x < 256; x++) { |
| 29 | float dx = x - cx; |
| 30 | dx *= dx; |
| 31 | float d = (dx + dy) / (cx/2); |
| 32 | int id = (int)d; |
| 33 | if (id > 255) { |
| 34 | id = 255; |
| 35 | } |
| 36 | p[x] = id; |
| 37 | } |
| 38 | } |
| 39 | bm.unlockPixels(); |
| 40 | return bm; |
| 41 | } |
| 42 | |
| 43 | class ExtractAlphaView : public SkView { |
| 44 | SkBitmap fBM8; |
| 45 | SkBitmap fBM32; |
| 46 | SkBitmap fBM4; |
| 47 | public: |
| 48 | ExtractAlphaView() { |
| 49 | fBM8 = make_bitmap(); |
| 50 | fBM8.copyTo(&fBM32, SkBitmap::kARGB_8888_Config); |
| 51 | fBM8.copyTo(&fBM4, SkBitmap::kARGB_4444_Config); |
| 52 | } |
| 53 | |
| 54 | protected: |
| 55 | // overrides from SkEventSink |
| 56 | virtual bool onQuery(SkEvent* evt) { |
| 57 | if (SampleCode::TitleQ(*evt)) { |
| 58 | SampleCode::TitleR(evt, "DitherBitmap"); |
| 59 | return true; |
| 60 | } |
| 61 | return this->INHERITED::onQuery(evt); |
| 62 | } |
| 63 | |
| 64 | void drawBG(SkCanvas* canvas) { |
| 65 | canvas->drawColor(0xFFDDDDDD); |
| 66 | } |
| 67 | |
| 68 | virtual void onDraw(SkCanvas* canvas) { |
| 69 | drawBG(canvas); |
reed@android.com | 34e8580 | 2009-09-02 21:11:44 +0000 | [diff] [blame] | 70 | |
reed@android.com | 113244f | 2009-08-31 21:04:24 +0000 | [diff] [blame] | 71 | SkPaint paint; |
reed@android.com | 34e8580 | 2009-09-02 21:11:44 +0000 | [diff] [blame] | 72 | paint.setAntiAlias(true); |
| 73 | paint.setStyle(SkPaint::kStroke_Style); |
| 74 | |
| 75 | SkMatrix matrix; |
| 76 | matrix.setScale(3.55f, 80.f); |
| 77 | canvas->setMatrix(matrix); |
| 78 | |
| 79 | paint.setStrokeWidth(0.0588f); |
| 80 | canvas->drawLine(10, 5, 30, 4.8f, paint); |
| 81 | |
| 82 | paint.setStrokeWidth(0.06f); |
| 83 | canvas->drawLine(20, 5, 40, 4.8f, paint); |
reed@android.com | 113244f | 2009-08-31 21:04:24 +0000 | [diff] [blame] | 84 | } |
| 85 | |
| 86 | private: |
| 87 | typedef SkView INHERITED; |
| 88 | }; |
| 89 | |
| 90 | ////////////////////////////////////////////////////////////////////////////// |
| 91 | |
| 92 | static SkView* MyFactory() { return new ExtractAlphaView; } |
| 93 | static SkViewRegister reg(MyFactory); |
| 94 | |