766 lines
22 KiB
C++
766 lines
22 KiB
C++
/*
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* Copyright 2011 Google Inc.
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*
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* Use of this source code is governed by a BSD-style license that can be
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* found in the LICENSE file.
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*/
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#include "include/core/SkBitmap.h"
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#include "include/core/SkCanvas.h"
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#include "include/core/SkColorFilter.h"
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#include "include/core/SkColorPriv.h"
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#include "include/core/SkFont.h"
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#include "include/core/SkGraphics.h"
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#include "include/core/SkPathBuilder.h"
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#include "include/core/SkRegion.h"
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#include "include/core/SkShader.h"
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#include "include/core/SkTime.h"
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#include "include/core/SkTypeface.h"
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#include "include/effects/SkGradientShader.h"
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#include "include/utils/SkParsePath.h"
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#include "samplecode/Sample.h"
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#include "src/utils/SkUTF.h"
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#include "tools/timer/TimeUtils.h"
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#include "src/core/SkGeometry.h"
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#include <stdlib.h>
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// http://code.google.com/p/skia/issues/detail?id=32
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static void test_cubic() {
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SkPoint src[4] = {
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{ 556.25000f, 523.03003f },
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{ 556.23999f, 522.96002f },
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{ 556.21997f, 522.89001f },
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{ 556.21997f, 522.82001f }
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};
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SkPoint dst[11];
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dst[10].set(42, -42); // one past the end, that we don't clobber these
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SkScalar tval[] = { 0.33333334f, 0.99999994f };
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SkChopCubicAt(src, dst, tval, 2);
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#if 0
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for (int i = 0; i < 11; i++) {
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SkDebugf("--- %d [%g %g]\n", i, dst[i].fX, dst[i].fY);
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}
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#endif
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}
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static void test_cubic2() {
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const char* str = "M2242 -590088L-377758 9.94099e+07L-377758 9.94099e+07L2242 -590088Z";
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SkPath path;
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SkParsePath::FromSVGString(str, &path);
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{
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SkRect r = path.getBounds();
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SkIRect ir;
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r.round(&ir);
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SkDebugf("[%g %g %g %g] [%x %x %x %x]\n",
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SkScalarToDouble(r.fLeft), SkScalarToDouble(r.fTop),
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SkScalarToDouble(r.fRight), SkScalarToDouble(r.fBottom),
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ir.fLeft, ir.fTop, ir.fRight, ir.fBottom);
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}
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SkBitmap bitmap;
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bitmap.allocN32Pixels(300, 200);
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SkCanvas canvas(bitmap);
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SkPaint paint;
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paint.setAntiAlias(true);
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canvas.drawPath(path, paint);
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}
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class PathView : public Sample {
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SkScalar fPrevSecs;
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public:
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SkScalar fDStroke, fStroke, fMinStroke, fMaxStroke;
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SkPath fPath[6];
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bool fShowHairline;
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bool fOnce;
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PathView() {
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fPrevSecs = 0;
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fOnce = false;
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}
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void init() {
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if (fOnce) {
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return;
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}
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fOnce = true;
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test_cubic();
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test_cubic2();
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fShowHairline = false;
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fDStroke = 1;
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fStroke = 10;
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fMinStroke = 10;
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fMaxStroke = 180;
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const SkScalar V = 85;
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fPath[0].moveTo(40, 70);
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fPath[0].lineTo(70, 70 + SK_ScalarHalf);
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fPath[0].lineTo(110, 70);
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fPath[1].moveTo(40, 70);
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fPath[1].lineTo(70, 70 - SK_ScalarHalf);
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fPath[1].lineTo(110, 70);
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fPath[2].moveTo(V, V);
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fPath[2].lineTo(50, V);
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fPath[2].lineTo(50, 50);
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fPath[3].moveTo(50, 50);
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fPath[3].lineTo(50, V);
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fPath[3].lineTo(V, V);
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fPath[4].moveTo(50, 50);
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fPath[4].lineTo(50, V);
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fPath[4].lineTo(52, 50);
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fPath[5].moveTo(52, 50);
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fPath[5].lineTo(50, V);
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fPath[5].lineTo(50, 50);
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this->setBGColor(0xFFDDDDDD);
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}
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protected:
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SkString name() override { return SkString("Paths"); }
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void drawPath(SkCanvas* canvas, const SkPath& path, SkPaint::Join j) {
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SkPaint paint;
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paint.setAntiAlias(true);
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paint.setStyle(SkPaint::kStroke_Style);
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paint.setStrokeJoin(j);
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paint.setStrokeWidth(fStroke);
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if (fShowHairline) {
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SkPath fill;
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paint.getFillPath(path, &fill);
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paint.setStrokeWidth(0);
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canvas->drawPath(fill, paint);
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} else {
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canvas->drawPath(path, paint);
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}
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paint.setColor(SK_ColorRED);
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paint.setStrokeWidth(0);
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canvas->drawPath(path, paint);
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}
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void onDrawContent(SkCanvas* canvas) override {
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this->init();
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canvas->translate(50, 50);
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static const SkPaint::Join gJoins[] = {
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SkPaint::kBevel_Join,
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SkPaint::kMiter_Join,
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SkPaint::kRound_Join
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};
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for (size_t i = 0; i < SK_ARRAY_COUNT(gJoins); i++) {
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canvas->save();
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for (size_t j = 0; j < SK_ARRAY_COUNT(fPath); j++) {
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this->drawPath(canvas, fPath[j], gJoins[i]);
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canvas->translate(200, 0);
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}
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canvas->restore();
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canvas->translate(0, 200);
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}
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}
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bool onAnimate(double nanos) override {
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SkScalar currSecs = TimeUtils::Scaled(1e-9 * nanos, 100);
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SkScalar delta = currSecs - fPrevSecs;
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fPrevSecs = currSecs;
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fStroke += fDStroke * delta;
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if (fStroke > fMaxStroke || fStroke < fMinStroke) {
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fDStroke = -fDStroke;
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}
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return true;
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}
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Sample::Click* onFindClickHandler(SkScalar x, SkScalar y, skui::ModifierKey modi) override {
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fShowHairline = !fShowHairline;
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return nullptr;
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}
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private:
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using INHERITED = Sample;
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};
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DEF_SAMPLE( return new PathView; )
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//////////////////////////////////////////////////////////////////////////////
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#include "include/effects/SkCornerPathEffect.h"
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#include "include/utils/SkRandom.h"
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class ArcToView : public Sample {
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bool fDoFrame, fDoCorner, fDoConic;
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SkPaint fPtsPaint, fSkeletonPaint, fCornerPaint;
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public:
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enum {
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N = 4
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};
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SkPoint fPts[N];
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ArcToView()
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: fDoFrame(false), fDoCorner(false), fDoConic(false)
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{
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SkRandom rand;
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for (int i = 0; i < N; ++i) {
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fPts[i].fX = 20 + rand.nextUScalar1() * 640;
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fPts[i].fY = 20 + rand.nextUScalar1() * 480;
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}
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const SkScalar rad = 50;
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fPtsPaint.setAntiAlias(true);
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fPtsPaint.setStrokeWidth(15);
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fPtsPaint.setStrokeCap(SkPaint::kRound_Cap);
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fCornerPaint.setAntiAlias(true);
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fCornerPaint.setStyle(SkPaint::kStroke_Style);
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fCornerPaint.setStrokeWidth(13);
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fCornerPaint.setColor(SK_ColorGREEN);
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fCornerPaint.setPathEffect(SkCornerPathEffect::Make(rad*2));
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fSkeletonPaint.setAntiAlias(true);
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fSkeletonPaint.setStyle(SkPaint::kStroke_Style);
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fSkeletonPaint.setColor(SK_ColorRED);
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}
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void toggle(bool& value) {
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value = !value;
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}
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protected:
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SkString name() override { return SkString("ArcTo"); }
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bool onChar(SkUnichar uni) override {
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switch (uni) {
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case '1': this->toggle(fDoFrame); return true;
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case '2': this->toggle(fDoCorner); return true;
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case '3': this->toggle(fDoConic); return true;
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default: break;
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}
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return false;
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}
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void makePath(SkPath* path) {
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path->moveTo(fPts[0]);
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for (int i = 1; i < N; ++i) {
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path->lineTo(fPts[i]);
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}
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if (!fDoFrame) {
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path->close();
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}
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}
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void onDrawContent(SkCanvas* canvas) override {
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canvas->drawPoints(SkCanvas::kPoints_PointMode, N, fPts, fPtsPaint);
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SkPath path;
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this->makePath(&path);
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if (fDoCorner) {
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canvas->drawPath(path, fCornerPaint);
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}
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canvas->drawPath(path, fSkeletonPaint);
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}
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Sample::Click* onFindClickHandler(SkScalar x, SkScalar y, skui::ModifierKey modi) override {
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const SkScalar tol = 4;
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const SkRect r = SkRect::MakeXYWH(x - tol, y - tol, tol * 2, tol * 2);
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for (int i = 0; i < N; ++i) {
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if (r.intersects(SkRect::MakeXYWH(fPts[i].fX, fPts[i].fY, 1, 1))) {
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return new Click([this, i](Click* c) {
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fPts[i] = c->fCurr;
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return true;
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});
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}
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}
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return nullptr;
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}
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private:
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using INHERITED = Sample;
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};
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DEF_SAMPLE( return new ArcToView; )
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/////////////
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class FatStroke : public Sample {
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bool fClosed, fShowStroke, fShowHidden, fShowSkeleton, fAsCurves = false;
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int fJoinType, fCapType;
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float fWidth = 30;
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SkPaint fPtsPaint, fHiddenPaint, fSkeletonPaint, fStrokePaint;
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public:
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enum {
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N = 4
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};
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SkPoint fPts[N];
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FatStroke() : fClosed(false), fShowStroke(true), fShowHidden(false), fShowSkeleton(true),
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fJoinType(0), fCapType(0)
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{
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SkRandom rand;
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for (int i = 0; i < N; ++i) {
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fPts[i].fX = 20 + rand.nextUScalar1() * 640;
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fPts[i].fY = 20 + rand.nextUScalar1() * 480;
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}
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fPtsPaint.setAntiAlias(true);
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fPtsPaint.setStrokeWidth(10);
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fPtsPaint.setStrokeCap(SkPaint::kRound_Cap);
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fHiddenPaint.setAntiAlias(true);
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fHiddenPaint.setStyle(SkPaint::kStroke_Style);
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fHiddenPaint.setColor(0xFF0000FF);
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fStrokePaint.setAntiAlias(true);
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fStrokePaint.setStyle(SkPaint::kStroke_Style);
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fStrokePaint.setStrokeWidth(50);
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fStrokePaint.setColor(0x8000FF00);
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fSkeletonPaint.setAntiAlias(true);
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fSkeletonPaint.setStyle(SkPaint::kStroke_Style);
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fSkeletonPaint.setColor(SK_ColorRED);
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}
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void toggle(bool& value) {
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value = !value;
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}
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void toggle3(int& value) {
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value = (value + 1) % 3;
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}
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protected:
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SkString name() override { return SkString("FatStroke"); }
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bool onChar(SkUnichar uni) override {
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switch (uni) {
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case '1': this->toggle(fShowSkeleton); return true;
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case '2': this->toggle(fShowStroke); return true;
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case '3': this->toggle(fShowHidden); return true;
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case '4': this->toggle3(fJoinType); return true;
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case '5': this->toggle3(fCapType); return true;
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case '6': this->toggle(fClosed); return true;
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case 'c': this->toggle(fAsCurves); return true;
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case '-': fWidth -= 5; return true;
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case '=': fWidth += 5; return true;
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default: break;
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}
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return false;
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}
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void makePath(SkPath* path) {
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path->moveTo(fPts[0]);
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if (fAsCurves) {
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for (int i = 1; i < N-2; ++i) {
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path->quadTo(fPts[i], (fPts[i+1] + fPts[i]) * 0.5f);
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}
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path->quadTo(fPts[N-2], fPts[N-1]);
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} else {
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for (int i = 1; i < N; ++i) {
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path->lineTo(fPts[i]);
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}
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}
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if (fClosed) {
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path->close();
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}
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}
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void onDrawContent(SkCanvas* canvas) override {
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canvas->drawColor(0xFFEEEEEE);
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SkPath path;
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this->makePath(&path);
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fStrokePaint.setStrokeWidth(fWidth);
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fStrokePaint.setStrokeJoin((SkPaint::Join)fJoinType);
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fStrokePaint.setStrokeCap((SkPaint::Cap)fCapType);
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if (fShowStroke) {
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canvas->drawPath(path, fStrokePaint);
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}
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if (fShowHidden) {
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SkPath hidden;
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fStrokePaint.getFillPath(path, &hidden);
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canvas->drawPath(hidden, fHiddenPaint);
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}
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if (fShowSkeleton) {
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canvas->drawPath(path, fSkeletonPaint);
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}
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canvas->drawPoints(SkCanvas::kPoints_PointMode, N, fPts, fPtsPaint);
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}
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Sample::Click* onFindClickHandler(SkScalar x, SkScalar y, skui::ModifierKey modi) override {
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const SkScalar tol = 4;
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const SkRect r = SkRect::MakeXYWH(x - tol, y - tol, tol * 2, tol * 2);
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for (int i = 0; i < N; ++i) {
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if (r.intersects(SkRect::MakeXYWH(fPts[i].fX, fPts[i].fY, 1, 1))) {
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return new Click([this, i](Click* c) {
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fPts[i] = c->fCurr;
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return true;
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});
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}
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}
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return nullptr;
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}
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private:
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using INHERITED = Sample;
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};
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DEF_SAMPLE( return new FatStroke; )
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static int compute_parallel_to_base(const SkPoint pts[4], SkScalar t[2]) {
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// F = At^3 + Bt^2 + Ct + D
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SkVector A = pts[3] - pts[0] + (pts[1] - pts[2]) * 3.0f;
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SkVector B = (pts[0] - pts[1] - pts[1] + pts[2]) * 3.0f;
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SkVector C = (pts[1] - pts[0]) * 3.0f;
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SkVector DA = pts[3] - pts[0];
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// F' = 3At^2 + 2Bt + C
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SkScalar a = 3 * A.cross(DA);
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SkScalar b = 2 * B.cross(DA);
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SkScalar c = C.cross(DA);
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int n = SkFindUnitQuadRoots(a, b, c, t);
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SkString str;
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for (int i = 0; i < n; ++i) {
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str.appendf(" %g", t[i]);
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}
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SkDebugf("roots %s\n", str.c_str());
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return n;
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}
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class CubicCurve : public Sample {
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public:
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enum {
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N = 4
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};
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SkPoint fPts[N];
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CubicCurve() {
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SkRandom rand;
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for (int i = 0; i < N; ++i) {
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fPts[i].fX = 20 + rand.nextUScalar1() * 640;
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fPts[i].fY = 20 + rand.nextUScalar1() * 480;
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}
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}
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protected:
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SkString name() override { return SkString("CubicCurve"); }
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void onDrawContent(SkCanvas* canvas) override {
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SkPaint paint;
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paint.setAntiAlias(true);
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{
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SkPath path;
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path.moveTo(fPts[0]);
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path.cubicTo(fPts[1], fPts[2], fPts[3]);
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paint.setStyle(SkPaint::kStroke_Style);
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canvas->drawPath(path, paint);
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}
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{
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paint.setColor(SK_ColorRED);
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SkScalar t[2];
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int n = compute_parallel_to_base(fPts, t);
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SkPoint loc;
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SkVector tan;
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for (int i = 0; i < n; ++i) {
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SkEvalCubicAt(fPts, t[i], &loc, &tan, nullptr);
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tan.setLength(30);
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canvas->drawLine(loc - tan, loc + tan, paint);
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}
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paint.setStrokeWidth(0.5f);
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canvas->drawLine(fPts[0], fPts[3], paint);
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paint.setColor(SK_ColorBLUE);
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paint.setStrokeWidth(6);
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SkEvalCubicAt(fPts, 0.5f, &loc, nullptr, nullptr);
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canvas->drawPoint(loc, paint);
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paint.setColor(0xFF008800);
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SkEvalCubicAt(fPts, 1.0f/3, &loc, nullptr, nullptr);
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canvas->drawPoint(loc, paint);
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SkEvalCubicAt(fPts, 2.0f/3, &loc, nullptr, nullptr);
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canvas->drawPoint(loc, paint);
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// n = SkFindCubicInflections(fPts, t);
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// printf("inflections %d %g %g\n", n, t[0], t[1]);
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}
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{
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paint.setStyle(SkPaint::kFill_Style);
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paint.setColor(SK_ColorRED);
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for (SkPoint p : fPts) {
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canvas->drawCircle(p.fX, p.fY, 8, paint);
|
|
}
|
|
}
|
|
}
|
|
|
|
Sample::Click* onFindClickHandler(SkScalar x, SkScalar y, skui::ModifierKey modi) override {
|
|
const SkScalar tol = 8;
|
|
const SkRect r = SkRect::MakeXYWH(x - tol, y - tol, tol * 2, tol * 2);
|
|
for (int i = 0; i < N; ++i) {
|
|
if (r.intersects(SkRect::MakeXYWH(fPts[i].fX, fPts[i].fY, 1, 1))) {
|
|
return new Click([this, i](Click* c) {
|
|
fPts[i] = c->fCurr;
|
|
return true;
|
|
});
|
|
}
|
|
}
|
|
return this->INHERITED::onFindClickHandler(x, y, modi);
|
|
}
|
|
|
|
private:
|
|
using INHERITED = Sample;
|
|
};
|
|
DEF_SAMPLE( return new CubicCurve; )
|
|
|
|
static SkPoint lerp(SkPoint a, SkPoint b, float t) {
|
|
return a * (1 - t) + b * t;
|
|
}
|
|
|
|
static int find_max_deviation_cubic(const SkPoint src[4], SkScalar ts[2]) {
|
|
// deviation = F' x (d - a) == 0, solve for t(s)
|
|
// F = At^3 + Bt^2 + Ct + D
|
|
// F' = 3At^2 + 2Bt + C
|
|
// Z = d - a
|
|
// F' x Z = 3(A x Z)t^2 + 2(B x Z)t + (C x Z)
|
|
//
|
|
SkVector A = src[3] + (src[1] - src[2]) * 3 - src[0];
|
|
SkVector B = (src[2] - src[1] - src[1] + src[0]) * 3;
|
|
SkVector C = (src[1] - src[0]) * 3;
|
|
SkVector Z = src[3] - src[0];
|
|
// now forumlate the quadratic coefficients we need to solve for t : F' x Z
|
|
return SkFindUnitQuadRoots(3 * A.cross(Z), 2 * B.cross(Z), C.cross(Z), ts);
|
|
}
|
|
|
|
class CubicCurve2 : public Sample {
|
|
public:
|
|
enum {
|
|
N = 7
|
|
};
|
|
SkPoint fPts[N];
|
|
SkPoint* fQuad = fPts + 4;
|
|
SkScalar fT = 0.5f;
|
|
bool fShowSub = false;
|
|
bool fShowFlatness = false;
|
|
bool fShowInnerQuads = false;
|
|
SkScalar fScale = 0.75;
|
|
|
|
CubicCurve2() {
|
|
fPts[0] = { 90, 300 };
|
|
fPts[1] = { 30, 60 };
|
|
fPts[2] = { 250, 30 };
|
|
fPts[3] = { 350, 200 };
|
|
|
|
fQuad[0] = fPts[0] + SkVector{ 300, 0};
|
|
fQuad[1] = fPts[1] + SkVector{ 300, 0};
|
|
fQuad[2] = fPts[2] + SkVector{ 300, 0};
|
|
}
|
|
|
|
protected:
|
|
SkString name() override { return SkString("CubicCurve2"); }
|
|
|
|
bool onChar(SkUnichar uni) override {
|
|
switch (uni) {
|
|
case 's': fShowSub = !fShowSub; break;
|
|
case 'f': fShowFlatness = !fShowFlatness; break;
|
|
case '-': fT -= 1.0f / 32; break;
|
|
case '=': fT += 1.0f / 32; break;
|
|
case 'q': fShowInnerQuads = !fShowInnerQuads; break;
|
|
default: return false;
|
|
}
|
|
fT = std::min(1.0f, std::max(0.0f, fT));
|
|
return true;
|
|
}
|
|
|
|
static void Dot(SkCanvas* canvas, SkPoint p, SkScalar radius, SkColor c) {
|
|
SkPaint paint;
|
|
paint.setAntiAlias(true);
|
|
paint.setColor(c);
|
|
canvas->drawCircle(p.fX, p.fY, radius, paint);
|
|
}
|
|
|
|
void showFrame(SkCanvas* canvas, const SkPoint pts[], int count, const SkPaint& p) {
|
|
SkPaint paint(p);
|
|
SkPoint storage[3 + 2 + 1];
|
|
SkPoint* tmp = storage;
|
|
const SkPoint* prev = pts;
|
|
int n = count;
|
|
for (int n = count; n > 0; --n) {
|
|
for (int i = 0; i < n; ++i) {
|
|
canvas->drawLine(prev[i], prev[i+1], paint);
|
|
tmp[i] = lerp(prev[i], prev[i+1], fT);
|
|
}
|
|
prev = tmp;
|
|
tmp += n;
|
|
}
|
|
|
|
paint.setColor(SK_ColorBLUE);
|
|
paint.setStyle(SkPaint::kFill_Style);
|
|
n = tmp - storage;
|
|
for (int i = 0; i < n; ++i) {
|
|
Dot(canvas, storage[i], 4, SK_ColorBLUE);
|
|
}
|
|
}
|
|
|
|
void showFlattness(SkCanvas* canvas) {
|
|
SkPaint paint;
|
|
paint.setStyle(SkPaint::kStroke_Style);
|
|
paint.setAntiAlias(true);
|
|
|
|
SkPaint paint2(paint);
|
|
paint2.setColor(0xFF008800);
|
|
|
|
paint.setColor(0xFF888888);
|
|
canvas->drawLine(fPts[0], fPts[3], paint);
|
|
canvas->drawLine(fQuad[0], fQuad[2], paint);
|
|
|
|
paint.setColor(0xFF0000FF);
|
|
SkPoint pts[2];
|
|
pts[0] = (fQuad[0] + fQuad[1] + fQuad[1] + fQuad[2])*0.25;
|
|
pts[1] = (fQuad[0] + fQuad[2]) * 0.5;
|
|
canvas->drawLine(pts[0], pts[1], paint);
|
|
|
|
// cubic
|
|
|
|
SkVector v0 = (fPts[0] - fPts[1] - fPts[1] + fPts[2]) * fScale;
|
|
SkVector v1 = (fPts[1] - fPts[2] - fPts[2] + fPts[3]) * fScale;
|
|
SkVector v = (v0 + v1) * 0.5f;
|
|
|
|
SkPoint anchor;
|
|
SkScalar ts[2];
|
|
int n = find_max_deviation_cubic(fPts, ts);
|
|
if (n > 0) {
|
|
SkEvalCubicAt(fPts, ts[0], &anchor, nullptr, nullptr);
|
|
canvas->drawLine(anchor, anchor + v, paint2);
|
|
canvas->drawLine(anchor, anchor + v0, paint);
|
|
if (n == 2) {
|
|
SkEvalCubicAt(fPts, ts[1], &anchor, nullptr, nullptr);
|
|
canvas->drawLine(anchor, anchor + v, paint2);
|
|
}
|
|
canvas->drawLine(anchor, anchor + v1, paint);
|
|
}
|
|
// not sure we can get here
|
|
}
|
|
|
|
void showInnerQuads(SkCanvas* canvas) {
|
|
auto draw_quad = [canvas](SkPoint a, SkPoint b, SkPoint c, SkColor color) {
|
|
SkPaint paint;
|
|
paint.setAntiAlias(true);
|
|
paint.setStroke(true);
|
|
paint.setColor(color);
|
|
|
|
canvas->drawPath(SkPathBuilder().moveTo(a).quadTo(b, c).detach(), paint);
|
|
};
|
|
|
|
SkPoint p0 = SkEvalQuadAt(&fPts[0], fT),
|
|
p1 = SkEvalQuadAt(&fPts[1], fT),
|
|
p2 = lerp(p0, p1, fT);
|
|
|
|
draw_quad(fPts[0], fPts[1], fPts[2], SK_ColorRED);
|
|
Dot(canvas, p0, 4, SK_ColorRED);
|
|
|
|
draw_quad(fPts[1], fPts[2], fPts[3], SK_ColorBLUE);
|
|
Dot(canvas, p1, 4, SK_ColorBLUE);
|
|
|
|
SkPaint paint;
|
|
paint.setAntiAlias(true);
|
|
paint.setColor(0xFF008800);
|
|
canvas->drawLine(p0, p1, paint);
|
|
Dot(canvas, p2, 4, 0xFF00AA00);
|
|
}
|
|
|
|
void onDrawContent(SkCanvas* canvas) override {
|
|
SkPaint paint;
|
|
paint.setAntiAlias(true);
|
|
|
|
{
|
|
paint.setStyle(SkPaint::kStroke_Style);
|
|
SkPath path;
|
|
path.moveTo(fPts[0]);
|
|
path.cubicTo(fPts[1], fPts[2], fPts[3]);
|
|
path.moveTo(fQuad[0]);
|
|
path.quadTo(fQuad[1], fQuad[2]);
|
|
canvas->drawPath(path, paint);
|
|
}
|
|
|
|
if (fShowSub) {
|
|
paint.setColor(SK_ColorRED);
|
|
paint.setStrokeWidth(1.7f);
|
|
this->showFrame(canvas, fPts, 3, paint);
|
|
this->showFrame(canvas, fQuad, 2, paint);
|
|
|
|
paint.setColor(SK_ColorBLACK);
|
|
paint.setStyle(SkPaint::kFill_Style);
|
|
SkFont font(nullptr, 20);
|
|
canvas->drawString(SkStringPrintf("t = %g", fT), 20, 20, font, paint);
|
|
}
|
|
|
|
if (fShowFlatness) {
|
|
this->showFlattness(canvas);
|
|
}
|
|
|
|
if (fShowInnerQuads) {
|
|
this->showInnerQuads(canvas);
|
|
}
|
|
|
|
paint.setColor(SK_ColorGRAY);
|
|
paint.setStroke(true);
|
|
canvas->drawPath(SkPathBuilder().addPolygon(fPts, 4, false).detach(), paint);
|
|
canvas->drawPath(SkPathBuilder().addPolygon(fQuad, 3, false).detach(), paint);
|
|
|
|
for (SkPoint p : fPts) {
|
|
Dot(canvas, p, 7, SK_ColorBLACK);
|
|
}
|
|
|
|
if (false) {
|
|
SkScalar ts[2];
|
|
int n = SkFindCubicInflections(fPts, ts);
|
|
for (int i = 0; i < n; ++i) {
|
|
SkPoint p;
|
|
SkEvalCubicAt(fPts, ts[i], &p, nullptr, nullptr);
|
|
canvas->drawCircle(p.fX, p.fY, 3, paint);
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
Sample::Click* onFindClickHandler(SkScalar x, SkScalar y, skui::ModifierKey modi) override {
|
|
const SkScalar tol = 8;
|
|
const SkRect r = SkRect::MakeXYWH(x - tol, y - tol, tol * 2, tol * 2);
|
|
for (int i = 0; i < N; ++i) {
|
|
if (r.intersects(SkRect::MakeXYWH(fPts[i].fX, fPts[i].fY, 1, 1))) {
|
|
return new Click([this, i](Click* c) {
|
|
fPts[i] = c->fCurr;
|
|
return true;
|
|
});
|
|
}
|
|
}
|
|
return this->INHERITED::onFindClickHandler(x, y, modi);
|
|
}
|
|
|
|
private:
|
|
using INHERITED = Sample;
|
|
};
|
|
DEF_SAMPLE( return new CubicCurve2; )
|
|
|