Home | History | Annotate | Download | only in gm 
      1 #include "gm.h"
      2 #include "SkGradientShader.h"
      3 
      4 namespace skiagm {
      5 
      6 struct GradData {
      7     int             fCount;
      8     const SkColor*  fColors;
      9     const SkScalar* fPos;
     10 };
     11 
     12 static const SkColor gColors[] = {
     13     SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorWHITE, SK_ColorBLACK
     14 };
     15 static const SkScalar gPos0[] = { 0, SK_Scalar1 };
     16 static const SkScalar gPos1[] = { SK_Scalar1/4, SK_Scalar1*3/4 };
     17 static const SkScalar gPos2[] = {
     18     0, SK_Scalar1/8, SK_Scalar1/2, SK_Scalar1*7/8, SK_Scalar1
     19 };
     20 
     21 static const GradData gGradData[] = {
     22     { 2, gColors, NULL },
     23     { 2, gColors, gPos0 },
     24     { 2, gColors, gPos1 },
     25     { 5, gColors, NULL },
     26     { 5, gColors, gPos2 }
     27 };
     28 
     29 static SkShader* MakeLinear(const SkPoint pts[2], const GradData& data,
     30                             SkShader::TileMode tm, SkUnitMapper* mapper) {
     31     return SkGradientShader::CreateLinear(pts, data.fColors, data.fPos,
     32                                           data.fCount, tm, mapper);
     33 }
     34 
     35 static SkShader* MakeRadial(const SkPoint pts[2], const GradData& data,
     36                             SkShader::TileMode tm, SkUnitMapper* mapper) {
     37     SkPoint center;
     38     center.set(SkScalarAve(pts[0].fX, pts[1].fX),
     39                SkScalarAve(pts[0].fY, pts[1].fY));
     40     return SkGradientShader::CreateRadial(center, center.fX, data.fColors,
     41                                           data.fPos, data.fCount, tm, mapper);
     42 }
     43 
     44 static SkShader* MakeSweep(const SkPoint pts[2], const GradData& data,
     45                            SkShader::TileMode tm, SkUnitMapper* mapper) {
     46     SkPoint center;
     47     center.set(SkScalarAve(pts[0].fX, pts[1].fX),
     48                SkScalarAve(pts[0].fY, pts[1].fY));
     49     return SkGradientShader::CreateSweep(center.fX, center.fY, data.fColors,
     50                                          data.fPos, data.fCount, mapper);
     51 }
     52 
     53 typedef SkShader* (*GradMaker)(const SkPoint pts[2], const GradData& data,
     54                      SkShader::TileMode tm, SkUnitMapper* mapper);
     55 static const GradMaker gGradMakers[] = {
     56     MakeLinear, MakeRadial, MakeSweep
     57 };
     58 
     59 ///////////////////////////////////////////////////////////////////////////////
     60 
     61 class GradientsGM : public GM {
     62 public:
     63 	GradientsGM() {}
     64 
     65 protected:
     66     SkString onShortName() {
     67         return SkString("gradients");
     68     }
     69 
     70 	SkISize onISize() { return make_isize(640, 380); }
     71 
     72     void drawBG(SkCanvas* canvas) {
     73         canvas->drawColor(0xFFDDDDDD);
     74     }
     75 
     76     virtual void onDraw(SkCanvas* canvas) {
     77         this->drawBG(canvas);
     78 
     79         SkPoint pts[2] = {
     80             { 0, 0 },
     81             { SkIntToScalar(100), SkIntToScalar(100) }
     82         };
     83         SkShader::TileMode tm = SkShader::kClamp_TileMode;
     84         SkRect r = { 0, 0, SkIntToScalar(100), SkIntToScalar(100) };
     85         SkPaint paint;
     86         paint.setAntiAlias(true);
     87 
     88         canvas->translate(SkIntToScalar(20), SkIntToScalar(20));
     89         for (size_t i = 0; i < SK_ARRAY_COUNT(gGradData); i++) {
     90             canvas->save();
     91             for (size_t j = 0; j < SK_ARRAY_COUNT(gGradMakers); j++) {
     92                 SkShader* shader = gGradMakers[j](pts, gGradData[i], tm, NULL);
     93                 paint.setShader(shader);
     94                 canvas->drawRect(r, paint);
     95                 shader->unref();
     96                 canvas->translate(0, SkIntToScalar(120));
     97             }
     98             canvas->restore();
     99             canvas->translate(SkIntToScalar(120), 0);
    100         }
    101     }
    102 
    103 private:
    104     typedef GM INHERITED;
    105 };
    106 
    107 ///////////////////////////////////////////////////////////////////////////////
    108 
    109 static GM* MyFactory(void*) { return new GradientsGM; }
    110 static GMRegistry reg(MyFactory);
    111 
    112 }
    113 
    114