/* * Copyright 2015 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 "SkAnimTimer.h" #include "SkCanvas.h" #include "SkGradientShader.h" #include "SkPatchUtils.h" #include "SkPerlinNoiseShader.h" static void draw_control_points(SkCanvas* canvas, const SkPoint cubics[12]) { //draw control points SkPaint paint; SkPoint bottom[SkPatchUtils::kNumPtsCubic]; SkPatchUtils::GetBottomCubic(cubics, bottom); SkPoint top[SkPatchUtils::kNumPtsCubic]; SkPatchUtils::GetTopCubic(cubics, top); SkPoint left[SkPatchUtils::kNumPtsCubic]; SkPatchUtils::GetLeftCubic(cubics, left); SkPoint right[SkPatchUtils::kNumPtsCubic]; SkPatchUtils::GetRightCubic(cubics, right); paint.setColor(SK_ColorBLACK); paint.setStrokeWidth(0.5f); SkPoint corners[4] = { bottom[0], bottom[3], top[0], top[3] }; canvas->drawPoints(SkCanvas::kLines_PointMode, 4, bottom, paint); canvas->drawPoints(SkCanvas::kLines_PointMode, 2, bottom + 1, paint); canvas->drawPoints(SkCanvas::kLines_PointMode, 4, top, paint); canvas->drawPoints(SkCanvas::kLines_PointMode, 4, left, paint); canvas->drawPoints(SkCanvas::kLines_PointMode, 4, right, paint); canvas->drawPoints(SkCanvas::kLines_PointMode, 2, top + 1, paint); canvas->drawPoints(SkCanvas::kLines_PointMode, 2, left + 1, paint); canvas->drawPoints(SkCanvas::kLines_PointMode, 2, right + 1, paint); paint.setStrokeWidth(2); paint.setColor(SK_ColorRED); canvas->drawPoints(SkCanvas::kPoints_PointMode, 4, corners, paint); paint.setColor(SK_ColorBLUE); canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, bottom + 1, paint); paint.setColor(SK_ColorCYAN); canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, top + 1, paint); paint.setColor(SK_ColorYELLOW); canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, left + 1, paint); paint.setColor(SK_ColorGREEN); canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, right + 1, paint); } // These are actually half the total width and hieghts const SkScalar TexWidth = 100.0f; const SkScalar TexHeight = 100.0f; class PerlinPatchView : public SampleView { sk_sp fShader0; sk_sp fShader1; sk_sp fShaderCompose; SkScalar fXFreq; SkScalar fYFreq; SkScalar fSeed; SkPoint fPts[SkPatchUtils::kNumCtrlPts]; SkScalar fTexX; SkScalar fTexY; SkScalar fTexScale; SkMatrix fInvMatrix; bool fShowGrid = false; public: PerlinPatchView() : fXFreq(0.025f), fYFreq(0.025f), fSeed(0.0f), fTexX(100.0), fTexY(50.0), fTexScale(1.0f) { const SkScalar s = 2; // The order of the colors and points is clockwise starting at upper-left corner. //top points fPts[0].set(100 * s, 100 * s); fPts[1].set(150 * s, 50 * s); fPts[2].set(250 * s, 150 * s); fPts[3].set(300 * s, 100 * s); //right points fPts[4].set(275 * s, 150 * s); fPts[5].set(350 * s, 250 * s); //bottom points fPts[6].set(300 * s, 300 * s); fPts[7].set(250 * s, 250 * s); //left points fPts[8].set(150 * s, 350 * s); fPts[9].set(100 * s, 300 * s); fPts[10].set(50 * s, 250 * s); fPts[11].set(150 * s, 150 * s); const SkColor colors[SkPatchUtils::kNumCorners] = { 0xFF5555FF, 0xFF8888FF, 0xFFCCCCFF }; const SkPoint points[2] = { SkPoint::Make(0.0f, 0.0f), SkPoint::Make(100.0f, 100.0f) }; fShader0 = SkGradientShader::MakeLinear(points, colors, nullptr, 3, SkShader::kMirror_TileMode, 0, nullptr); } protected: // overrides from SkEventSink bool onQuery(SkEvent* evt) override { if (SampleCode::TitleQ(*evt)) { SampleCode::TitleR(evt, "PerlinPatch"); return true; } SkUnichar uni; if (SampleCode::CharQ(*evt, &uni)) { switch (uni) { case 'g': fShowGrid = !fShowGrid; return true; default: break; } } return this->INHERITED::onQuery(evt); } bool onAnimate(const SkAnimTimer& timer) override { fSeed += 0.005f; return true; } void onDrawContent(SkCanvas* canvas) override { if (!canvas->getTotalMatrix().invert(&fInvMatrix)) { return; } SkPaint paint; SkScalar texWidth = fTexScale * TexWidth; SkScalar texHeight = fTexScale * TexHeight; const SkPoint texCoords[SkPatchUtils::kNumCorners] = { { fTexX - texWidth, fTexY - texHeight}, { fTexX + texWidth, fTexY - texHeight}, { fTexX + texWidth, fTexY + texHeight}, { fTexX - texWidth, fTexY + texHeight}} ; SkScalar scaleFreq = 2.0; fShader1 = SkPerlinNoiseShader::MakeImprovedNoise(fXFreq/scaleFreq, fYFreq/scaleFreq, 4, fSeed); fShaderCompose = SkShader::MakeComposeShader(fShader0, fShader1, SkBlendMode::kSrcOver); paint.setShader(fShaderCompose); const SkPoint* tex = texCoords; if (fShowGrid) { tex = nullptr; } canvas->drawPatch(fPts, nullptr, tex, SkBlendMode::kSrc, paint); draw_control_points(canvas, fPts); } class PtClick : public Click { public: int fIndex; PtClick(SkView* view, int index) : Click(view), fIndex(index) {} }; static bool hittest(const SkPoint& pt, SkScalar x, SkScalar y) { return SkPoint::Length(pt.fX - x, pt.fY - y) < SkIntToScalar(5); } SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned modi) override { // holding down shift if (1 == modi) { return new PtClick(this, -1); } // holding down ctrl if (2 == modi) { return new PtClick(this, -2); } SkPoint clickPoint = {x, y}; fInvMatrix.mapPoints(&clickPoint, 1); for (size_t i = 0; i < SK_ARRAY_COUNT(fPts); i++) { if (hittest(fPts[i], clickPoint.fX, clickPoint.fY)) { return new PtClick(this, (int)i); } } return this->INHERITED::onFindClickHandler(x, y, modi); } bool onClick(Click* click) override { PtClick* ptClick = (PtClick*)click; if (ptClick->fIndex >= 0) { fPts[ptClick->fIndex].set(click->fCurr.fX , click->fCurr.fY ); } else if (-1 == ptClick->fIndex) { SkScalar xDiff = click->fPrev.fX - click->fCurr.fX; SkScalar yDiff = click->fPrev.fY - click->fCurr.fY; fTexX += xDiff * fTexScale; fTexY += yDiff * fTexScale; } else if (-2 == ptClick->fIndex) { SkScalar yDiff = click->fCurr.fY - click->fPrev.fY; fTexScale += yDiff / 10.0f; fTexScale = SkTMax(0.1f, SkTMin(20.f, fTexScale)); } return true; } private: typedef SampleView INHERITED; }; DEF_SAMPLE( return new PerlinPatchView(); )