| |
| /* |
| * 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 "SampleCode.h" |
| #include "SkView.h" |
| #include "SkCanvas.h" |
| #include "Sk64.h" |
| #include "SkGradientShader.h" |
| #include "SkString.h" |
| |
| static void draw_gradient2(SkCanvas* canvas, const SkRect& rect, SkScalar delta) { |
| SkColor colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorMAGENTA }; |
| SkScalar pos[] = { 0, SkFloatToScalar(0.25f), SkFloatToScalar(0.75f), SK_Scalar1 }; |
| |
| SkScalar l = rect.fLeft; |
| SkScalar t = rect.fTop; |
| SkScalar w = rect.width(); |
| SkScalar h = rect.height(); |
| |
| SkASSERT(0 == SkScalarMod(w, SK_Scalar1 * 5)); |
| |
| SkPoint c0 = { l + 2 * w / 5 + delta, t + h / 2 }; |
| SkPoint c1 = { l + 3 * w / 5, t + h / 2 }; |
| SkScalar r0 = w / 5; |
| SkScalar r1 = 2 * w / 5; |
| SkShader* s = SkGradientShader::CreateTwoPointConical(c0, r0, c1, r1, colors, |
| pos, SK_ARRAY_COUNT(pos), |
| SkShader::kClamp_TileMode); |
| SkPaint paint; |
| paint.setShader(s)->unref(); |
| |
| canvas->drawRect(rect, paint); |
| } |
| |
| |
| class DegenerateTwoPtRadialsView : public SampleView { |
| |
| public: |
| DegenerateTwoPtRadialsView() { |
| fTime = 0; |
| this->setBGColor(0xFFDDDDDD); |
| } |
| |
| protected: |
| // overrides from SkEventSink |
| virtual bool onQuery(SkEvent* evt) { |
| if (SampleCode::TitleQ(*evt)) { |
| SampleCode::TitleR(evt, "DegenerateTwoPtRadials"); |
| return true; |
| } |
| return this->INHERITED::onQuery(evt); |
| } |
| |
| virtual void onDrawContent(SkCanvas* canvas) { |
| fTime += SampleCode::GetAnimSecondsDelta(); |
| SkScalar delta = fTime / 15.f; |
| int intPart = SkScalarFloor(delta); |
| delta = delta - SK_Scalar1 * intPart; |
| if (intPart % 2) { |
| delta = SK_Scalar1 - delta; |
| } |
| delta -= SK_ScalarHalf; |
| static const int DELTA_SCALE = 500; |
| delta /= DELTA_SCALE; |
| |
| SkScalar w = SK_Scalar1 * 500; |
| SkScalar h = SK_Scalar1 * 500; |
| SkScalar l = SK_Scalar1 * 100; |
| SkScalar t = SK_Scalar1 * 100; |
| draw_gradient2(canvas, SkRect::MakeXYWH(l, t, w, h), delta); |
| SkString txt; |
| txt.appendf("gap at \"tangent\" pt = %f", SkScalarToFloat(delta)); |
| SkPaint paint; |
| paint.setAntiAlias(true); |
| paint.setColor(SK_ColorBLACK); |
| canvas->drawText(txt.c_str(), txt.size(), l + w/2 + w*DELTA_SCALE*delta, t + h + SK_Scalar1 * 10, paint); |
| this->inval(NULL); |
| } |
| |
| private: |
| SkScalar fTime; |
| typedef SampleView INHERITED; |
| }; |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| |
| static SkView* MyFactory() { return new DegenerateTwoPtRadialsView; } |
| static SkViewRegister reg(MyFactory); |