| /* |
| * Copyright 2011 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| #include "include/core/SkCanvas.h" |
| #include "include/effects/SkGradientShader.h" |
| #include "samplecode/Sample.h" |
| |
| static sk_sp<SkShader> setgrad(const SkRect& r, SkColor c0, SkColor c1) { |
| SkColor colors[] = { c0, c1 }; |
| SkPoint pts[] = { { r.fLeft, r.fTop }, { r.fRight, r.fTop } }; |
| return SkGradientShader::MakeLinear(pts, colors, nullptr, 2, SkTileMode::kClamp); |
| } |
| |
| static void test_alphagradients(SkCanvas* canvas) { |
| SkRect r; |
| r.setLTRB(10, 10, 410, 30); |
| SkPaint p, p2; |
| p2.setStyle(SkPaint::kStroke_Style); |
| |
| p.setShader(setgrad(r, 0xFF00FF00, 0x0000FF00)); |
| canvas->drawRect(r, p); |
| canvas->drawRect(r, p2); |
| |
| r.offset(0, r.height() + SkIntToScalar(4)); |
| p.setShader(setgrad(r, 0xFF00FF00, 0x00000000)); |
| canvas->drawRect(r, p); |
| canvas->drawRect(r, p2); |
| |
| r.offset(0, r.height() + SkIntToScalar(4)); |
| p.setShader(setgrad(r, 0xFF00FF00, 0x00FF0000)); |
| canvas->drawRect(r, p); |
| canvas->drawRect(r, p2); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| struct GradData { |
| int fCount; |
| const SkColor* fColors; |
| const SkScalar* fPos; |
| }; |
| |
| static const SkColor gColors[] = { |
| SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorWHITE, SK_ColorBLACK |
| }; |
| static const SkScalar gPos0[] = { 0, SK_Scalar1 }; |
| static const SkScalar gPos1[] = { SK_Scalar1/4, SK_Scalar1*3/4 }; |
| static const SkScalar gPos2[] = { |
| 0, SK_Scalar1/8, SK_Scalar1/2, SK_Scalar1*7/8, SK_Scalar1 |
| }; |
| |
| static const GradData gGradData[] = { |
| { 2, gColors, nullptr }, |
| { 2, gColors, gPos0 }, |
| { 2, gColors, gPos1 }, |
| { 5, gColors, nullptr }, |
| { 5, gColors, gPos2 } |
| }; |
| |
| static sk_sp<SkShader> MakeLinear(const SkPoint pts[2], const GradData& data, SkTileMode tm) { |
| return SkGradientShader::MakeLinear(pts, data.fColors, data.fPos, data.fCount, tm); |
| } |
| |
| static sk_sp<SkShader> MakeRadial(const SkPoint pts[2], const GradData& data, SkTileMode tm) { |
| SkPoint center; |
| center.set(SkScalarAve(pts[0].fX, pts[1].fX), |
| SkScalarAve(pts[0].fY, pts[1].fY)); |
| return SkGradientShader::MakeRadial(center, center.fX, data.fColors, |
| data.fPos, data.fCount, tm); |
| } |
| |
| static sk_sp<SkShader> MakeSweep(const SkPoint pts[2], const GradData& data, SkTileMode tm) { |
| SkPoint center; |
| center.set(SkScalarAve(pts[0].fX, pts[1].fX), |
| SkScalarAve(pts[0].fY, pts[1].fY)); |
| return SkGradientShader::MakeSweep(center.fX, center.fY, data.fColors, data.fPos, data.fCount); |
| } |
| |
| static sk_sp<SkShader> Make2Conical(const SkPoint pts[2], const GradData& data, SkTileMode tm) { |
| SkPoint center0, center1; |
| center0.set(SkScalarAve(pts[0].fX, pts[1].fX), |
| SkScalarAve(pts[0].fY, pts[1].fY)); |
| center1.set(SkScalarInterp(pts[0].fX, pts[1].fX, SkIntToScalar(3)/5), |
| SkScalarInterp(pts[0].fY, pts[1].fY, SkIntToScalar(1)/4)); |
| return SkGradientShader::MakeTwoPointConical( |
| center1, (pts[1].fX - pts[0].fX) / 7, |
| center0, (pts[1].fX - pts[0].fX) / 2, |
| data.fColors, data.fPos, data.fCount, tm); |
| } |
| |
| static sk_sp<SkShader> Make2ConicalConcentric(const SkPoint pts[2], const GradData& data, |
| SkTileMode tm) { |
| SkPoint center; |
| center.set(SkScalarAve(pts[0].fX, pts[1].fX), |
| SkScalarAve(pts[0].fY, pts[1].fY)); |
| return SkGradientShader::MakeTwoPointConical( |
| center, (pts[1].fX - pts[0].fX) / 7, |
| center, (pts[1].fX - pts[0].fX) / 2, |
| data.fColors, data.fPos, data.fCount, tm); |
| } |
| |
| typedef sk_sp<SkShader> (*GradMaker)(const SkPoint pts[2], const GradData& data, SkTileMode tm); |
| |
| static const GradMaker gGradMakers[] = { |
| MakeLinear, MakeRadial, MakeSweep, Make2Conical, Make2ConicalConcentric |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| class GradientsView : public Sample { |
| public: |
| GradientsView() { |
| this->setBGColor(0xFFDDDDDD); |
| } |
| |
| protected: |
| SkString name() override { return SkString("Gradients"); } |
| |
| void onDrawContent(SkCanvas* canvas) override { |
| SkPoint pts[2] = { |
| { 0, 0 }, |
| { SkIntToScalar(100), SkIntToScalar(100) } |
| }; |
| SkRect r = { 0, 0, SkIntToScalar(100), SkIntToScalar(100) }; |
| SkPaint paint; |
| paint.setDither(true); |
| |
| canvas->save(); |
| canvas->translate(SkIntToScalar(20), SkIntToScalar(10)); |
| |
| for (int tm = 0; tm < kSkTileModeCount; ++tm) { |
| canvas->save(); |
| for (size_t i = 0; i < SK_ARRAY_COUNT(gGradData); i++) { |
| canvas->save(); |
| for (size_t j = 0; j < SK_ARRAY_COUNT(gGradMakers); j++) { |
| paint.setShader(gGradMakers[j](pts, gGradData[i], (SkTileMode)tm)); |
| canvas->drawRect(r, paint); |
| canvas->translate(0, SkIntToScalar(120)); |
| } |
| canvas->restore(); |
| canvas->translate(SkIntToScalar(120), 0); |
| } |
| canvas->restore(); |
| canvas->translate(SK_ARRAY_COUNT(gGradData)*SkIntToScalar(120), 0); |
| } |
| canvas->restore(); |
| |
| canvas->translate(0, SkIntToScalar(370)); |
| if ((false)) { // avoid bit rot, suppress warning |
| test_alphagradients(canvas); |
| } |
| } |
| |
| private: |
| using INHERITED = Sample; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| DEF_SAMPLE( return new GradientsView(); ) |