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      1 /*
      2  * Copyright 2011 Google Inc.
      3  *
      4  * Use of this source code is governed by a BSD-style license that can be
      5  * found in the LICENSE file.
      6  */
      7 
      8 #include "Sample.h"
      9 #include "SkAAClip.h"
     10 #include "SkCanvas.h"
     11 #include "SkColorPriv.h"
     12 #include "SkFont.h"
     13 #include "SkPaint.h"
     14 #include "SkPath.h"
     15 #include "SkRandom.h"
     16 #include "SkClipOpPriv.h"
     17 
     18 constexpr int W = 150;
     19 constexpr int H = 200;
     20 
     21 static void show_text(SkCanvas* canvas, bool doAA) {
     22     SkRandom rand;
     23     SkPaint paint;
     24     SkFont font(nullptr, 20);
     25     font.setEdging(doAA ? SkFont::Edging::kSubpixelAntiAlias : SkFont::Edging::kAlias);
     26 
     27     for (int i = 0; i < 200; ++i) {
     28         paint.setColor((SK_A32_MASK << SK_A32_SHIFT) | rand.nextU());
     29         canvas->drawString("Hamburgefons", rand.nextSScalar1() * W, rand.nextSScalar1() * H + 20,
     30                            font, paint);
     31     }
     32 }
     33 
     34 static void show_fill(SkCanvas* canvas, bool doAA) {
     35     SkRandom rand;
     36     SkPaint paint;
     37     paint.setAntiAlias(doAA);
     38 
     39     for (int i = 0; i < 50; ++i) {
     40         SkRect r;
     41         SkPath p;
     42 
     43         r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
     44                   rand.nextUScalar1() * W, rand.nextUScalar1() * H);
     45         paint.setColor(rand.nextU());
     46         canvas->drawRect(r, paint);
     47 
     48         r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
     49                   rand.nextUScalar1() * W, rand.nextUScalar1() * H);
     50         paint.setColor(rand.nextU());
     51         p.addOval(r);
     52         canvas->drawPath(p, paint);
     53     }
     54 }
     55 
     56 static SkScalar randRange(SkRandom& rand, SkScalar min, SkScalar max) {
     57     SkASSERT(min <= max);
     58     return min + rand.nextUScalar1() * (max - min);
     59 }
     60 
     61 static void show_stroke(SkCanvas* canvas, bool doAA, SkScalar strokeWidth, int n) {
     62     SkRandom rand;
     63     SkPaint paint;
     64     paint.setAntiAlias(doAA);
     65     paint.setStyle(SkPaint::kStroke_Style);
     66     paint.setStrokeWidth(strokeWidth);
     67 
     68     for (int i = 0; i < n; ++i) {
     69         SkRect r;
     70         SkPath p;
     71 
     72         r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
     73                   rand.nextUScalar1() * W, rand.nextUScalar1() * H);
     74         paint.setColor(rand.nextU());
     75         canvas->drawRect(r, paint);
     76 
     77         r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
     78                   rand.nextUScalar1() * W, rand.nextUScalar1() * H);
     79         paint.setColor(rand.nextU());
     80         p.addOval(r);
     81         canvas->drawPath(p, paint);
     82 
     83         const SkScalar minx = -SkIntToScalar(W)/4;
     84         const SkScalar maxx = 5*SkIntToScalar(W)/4;
     85         const SkScalar miny = -SkIntToScalar(H)/4;
     86         const SkScalar maxy = 5*SkIntToScalar(H)/4;
     87         paint.setColor(rand.nextU());
     88         canvas->drawLine(randRange(rand, minx, maxx), randRange(rand, miny, maxy),
     89                          randRange(rand, minx, maxx), randRange(rand, miny, maxy),
     90                          paint);
     91     }
     92 }
     93 
     94 static void show_hair(SkCanvas* canvas, bool doAA) {
     95     show_stroke(canvas, doAA, 0, 150);
     96 }
     97 
     98 static void show_thick(SkCanvas* canvas, bool doAA) {
     99     show_stroke(canvas, doAA, SkIntToScalar(5), 50);
    100 }
    101 
    102 typedef void (*CanvasProc)(SkCanvas*, bool);
    103 
    104 class ClipView : public Sample {
    105 public:
    106     ClipView() {
    107         SkAAClip clip;
    108         SkIRect r = { -2, -3, 842, 18 };
    109         clip.setRect(r);
    110     }
    111 
    112     virtual ~ClipView() {
    113     }
    114 
    115 protected:
    116     virtual bool onQuery(Sample::Event* evt) {
    117         if (Sample::TitleQ(*evt)) {
    118             Sample::TitleR(evt, "Clip");
    119             return true;
    120         }
    121         return this->INHERITED::onQuery(evt);
    122     }
    123 
    124     virtual void onDrawContent(SkCanvas* canvas) {
    125         canvas->drawColor(SK_ColorWHITE);
    126         canvas->translate(SkIntToScalar(20), SkIntToScalar(20));
    127 
    128         static const CanvasProc gProc[] = {
    129             show_text, show_thick, show_hair, show_fill
    130         };
    131 
    132         SkRect r = { 0, 0, SkIntToScalar(W), SkIntToScalar(H) };
    133         SkPath clipPath;
    134         r.inset(SK_Scalar1 / 4, SK_Scalar1 / 4);
    135         clipPath.addRoundRect(r, SkIntToScalar(20), SkIntToScalar(20));
    136 
    137 //        clipPath.toggleInverseFillType();
    138 
    139         for (int aa = 0; aa <= 1; ++aa) {
    140             canvas->save();
    141             for (size_t i = 0; i < SK_ARRAY_COUNT(gProc); ++i) {
    142                 canvas->save();
    143                 canvas->clipPath(clipPath, kIntersect_SkClipOp, SkToBool(aa));
    144 //                canvas->drawColor(SK_ColorWHITE);
    145                 gProc[i](canvas, SkToBool(aa));
    146                 canvas->restore();
    147                 canvas->translate(W * SK_Scalar1 * 8 / 7, 0);
    148             }
    149             canvas->restore();
    150             canvas->translate(0, H * SK_Scalar1 * 8 / 7);
    151         }
    152     }
    153 
    154 private:
    155     typedef Sample INHERITED;
    156 };
    157 
    158 //////////////////////////////////////////////////////////////////////////////
    159 
    160 DEF_SAMPLE( return new ClipView(); )
    161