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/*
* 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<SkShader> fShader0;
sk_sp<SkShader> fShader1;
sk_sp<SkShader> 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(); )
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