gm/pathfill.cpp

   1
   2 /*
   3  * Copyright 2011 Google Inc.
   4  *
   5  * Use of this source code is governed by a BSD-style license that can be
   6  * found in the LICENSE file.
   7  */
   8 #include "gm.h"
   9
  10 typedef SkScalar (*MakePathProc)(SkPath*);
  11
  12 static SkScalar make_frame(SkPath* path) {
  13     SkRect r = { SkIntToScalar(10), SkIntToScalar(10),
  14                  SkIntToScalar(630), SkIntToScalar(470) };
  15     path->addRoundRect(r, SkIntToScalar(15), SkIntToScalar(15));
  16
  17     SkPaint paint;
  18     paint.setStyle(SkPaint::kStroke_Style);
  19     paint.setStrokeWidth(SkIntToScalar(5));
  20     paint.getFillPath(*path, path);
  21     return SkIntToScalar(15);
  22 }
  23
  24 static SkScalar make_triangle(SkPath* path) {
  25     static const int gCoord[] = {
  26         10, 20, 15, 5, 30, 30
  27     };
  28     path->moveTo(SkIntToScalar(gCoord[0]), SkIntToScalar(gCoord[1]));
  29     path->lineTo(SkIntToScalar(gCoord[2]), SkIntToScalar(gCoord[3]));
  30     path->lineTo(SkIntToScalar(gCoord[4]), SkIntToScalar(gCoord[5]));
  31     path->close();
  32     path->offset(SkIntToScalar(10), SkIntToScalar(0));
  33     return SkIntToScalar(30);
  34 }
  35
  36 static SkScalar make_rect(SkPath* path) {
  37     SkRect r = { SkIntToScalar(10), SkIntToScalar(10),
  38                  SkIntToScalar(30), SkIntToScalar(30) };
  39     path->addRect(r);
  40     path->offset(SkIntToScalar(10), SkIntToScalar(0));
  41     return SkIntToScalar(30);
  42 }
  43
  44 static SkScalar make_oval(SkPath* path) {
  45     SkRect r = { SkIntToScalar(10), SkIntToScalar(10),
  46                  SkIntToScalar(30), SkIntToScalar(30) };
  47     path->addOval(r);
  48     path->offset(SkIntToScalar(10), SkIntToScalar(0));
  49     return SkIntToScalar(30);
  50 }
  51
  52 static SkScalar make_sawtooth(SkPath* path) {
  53     SkScalar x = SkIntToScalar(20);
  54     SkScalar y = SkIntToScalar(20);
  55     const SkScalar x0 = x;
  56     const SkScalar dx = SK_Scalar1 * 5;
  57     const SkScalar dy = SK_Scalar1 * 10;
  58
  59     path->moveTo(x, y);
  60     for (int i = 0; i < 32; i++) {
  61         x += dx;
  62         path->lineTo(x, y - dy);
  63         x += dx;
  64         path->lineTo(x, y + dy);
  65     }
  66     path->lineTo(x, y + (2 * dy));
  67     path->lineTo(x0, y + (2 * dy));
  68     path->close();
  69     return SkIntToScalar(30);
  70 }
  71
  72 static SkScalar make_star(SkPath* path, int n) {
  73     const SkScalar c = SkIntToScalar(45);
  74     const SkScalar r = SkIntToScalar(20);
  75
  76     SkScalar rad = -SK_ScalarPI / 2;
  77     const SkScalar drad = (n >> 1) * SK_ScalarPI * 2 / n;
  78
  79     path->moveTo(c, c - r);
  80     for (int i = 1; i < n; i++) {
  81         rad += drad;
  82         SkScalar cosV, sinV = SkScalarSinCos(rad, &cosV);
  83         path->lineTo(c + SkScalarMul(cosV, r), c + SkScalarMul(sinV, r));
  84     }
  85     path->close();
  86     return r * 2 * 6 / 5;
  87 }
  88
  89 static SkScalar make_star_5(SkPath* path) { return make_star(path, 5); }
  90 static SkScalar make_star_13(SkPath* path) { return make_star(path, 13); }
  91
  92 // We don't expect any output from this path.
  93 static SkScalar make_line(SkPath* path) {
  94     path->moveTo(SkIntToScalar(30), SkIntToScalar(30));
  95     path->lineTo(SkIntToScalar(120), SkIntToScalar(40));
  96     path->close();
  97     path->moveTo(SkIntToScalar(150), SkIntToScalar(30));
  98     path->lineTo(SkIntToScalar(150), SkIntToScalar(30));
  99     path->lineTo(SkIntToScalar(300), SkIntToScalar(40));
 100     path->close();
 101     return SkIntToScalar(40);
 102 }
 103
 104 static const MakePathProc gProcs[] = {
 105     make_frame,
 106     make_triangle,
 107     make_rect,
 108     make_oval,
 109     make_sawtooth,
 110     make_star_5,
 111     make_star_13,
 112     make_line,
 113 };
 114
 115 #define N   SK_ARRAY_COUNT(gProcs)
 116
 117 class PathFillGM : public skiagm::GM {
 118     SkPath  fPath[N];
 119     SkScalar fDY[N];
 120 protected:
 121     void onOnceBeforeDraw() override {
 122         for (size_t i = 0; i < N; i++) {
 123             fDY[i] = gProcs[i](&fPath[i]);
 124         }
 125     }
 126
 127
 128     SkString onShortName() override {
 129         return SkString("pathfill");
 130     }
 131
 132     SkISize onISize() override {
 133         return SkISize::Make(640, 480);
 134     }
 135
 136     void onDraw(SkCanvas* canvas) override {
 137         SkPaint paint;
 138         paint.setAntiAlias(true);
 139
 140         for (size_t i = 0; i < N; i++) {
 141             canvas->drawPath(fPath[i], paint);
 142             canvas->translate(SkIntToScalar(0), fDY[i]);
 143         }
 144     }
 145
 146 private:
 147     typedef skiagm::GM INHERITED;
 148 };
 149
 150 // test inverse-fill w/ a clip that completely excludes the geometry
 151 class PathInverseFillGM : public skiagm::GM {
 152     SkPath  fPath[N];
 153     SkScalar fDY[N];
 154 protected:
 155     void onOnceBeforeDraw() override {
 156         for (size_t i = 0; i < N; i++) {
 157             fDY[i] = gProcs[i](&fPath[i]);
 158         }
 159     }
 160
 161     SkString onShortName() override {
 162         return SkString("pathinvfill");
 163     }
 164
 165     SkISize onISize() override {
 166         return SkISize::Make(450, 220);
 167     }
 168
 169     static void show(SkCanvas* canvas, const SkPath& path, const SkPaint& paint,
 170                      const SkRect* clip, SkScalar top, const SkScalar bottom) {
 171         canvas->save();
 172         if (clip) {
 173             SkRect r = *clip;
 174             r.fTop = top;
 175             r.fBottom = bottom;
 176             canvas->clipRect(r);
 177         }
 178         canvas->drawPath(path, paint);
 179         canvas->restore();
 180     }
 181
 182     void onDraw(SkCanvas* canvas) override {
 183         SkPath path;
 184
 185         path.addCircle(SkIntToScalar(50), SkIntToScalar(50), SkIntToScalar(40));
 186         path.toggleInverseFillType();
 187
 188         SkRect clipR = { 0, 0, SkIntToScalar(100), SkIntToScalar(200) };
 189
 190         canvas->translate(SkIntToScalar(10), SkIntToScalar(10));
 191
 192         for (int doclip = 0; doclip <= 1; ++doclip) {
 193             for (int aa = 0; aa <= 1; ++aa) {
 194                 SkPaint paint;
 195                 paint.setAntiAlias(SkToBool(aa));
 196
 197                 canvas->save();
 198                 canvas->clipRect(clipR);
 199
 200                 const SkRect* clipPtr = doclip ? &clipR : NULL;
 201
 202                 show(canvas, path, paint, clipPtr, clipR.fTop, clipR.centerY());
 203                 show(canvas, path, paint, clipPtr, clipR.centerY(), clipR.fBottom);
 204
 205                 canvas->restore();
 206                 canvas->translate(SkIntToScalar(110), 0);
 207             }
 208         }
 209     }
 210
 211 private:
 212     typedef skiagm::GM INHERITED;
 213 };
 214
 215 ///////////////////////////////////////////////////////////////////////////////
 216
 217 static skiagm::GM* MyFactory(void*) { return new PathFillGM; }
 218 static skiagm::GMRegistry reg(MyFactory);
 219
 220 static skiagm::GM* F1(void*) { return new PathInverseFillGM; }
 221 static skiagm::GMRegistry gR1(F1);