gm/convex_all_line_paths.cpp - platform/external/skia - Gitiles

 /*
  * 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 "gm.h"
 #include "SkPolyUtils.h"
 #include "SkPathPriv.h"

 static void create_ngon(int n, SkPoint* pts, SkScalar width, SkScalar height) {
     float angleStep = 360.0f / n, angle = 0.0f, sin, cos;
     if ((n % 2) == 1) {
         angle = angleStep/2.0f;
     }

     for (int i = 0; i < n; ++i) {
         sin = SkScalarSinCos(SkDegreesToRadians(angle), &cos);
         pts[i].fX = -sin * width;
         pts[i].fY = cos * height;
         angle += angleStep;
     }
 }

 namespace ConvexLineOnlyData {
 // narrow rect
 const SkPoint gPoints0[] = {
     { -1.5f, -50.0f },
     { 1.5f, -50.0f },
     { 1.5f,  50.0f },
     { -1.5f,  50.0f }
 };
 // narrow rect on an angle
 const SkPoint gPoints1[] = {
     { -50.0f, -49.0f },
     { -49.0f, -50.0f },
     { 50.0f,  49.0f },
     { 49.0f,  50.0f }
 };
 // trap - narrow on top - wide on bottom
 const SkPoint gPoints2[] = {
     { -10.0f, -50.0f },
     { 10.0f, -50.0f },
     { 50.0f,  50.0f },
     { -50.0f,  50.0f }
 };
 // wide skewed rect
 const SkPoint gPoints3[] = {
     { -50.0f, -50.0f },
     { 0.0f, -50.0f },
     { 50.0f,  50.0f },
     { 0.0f,  50.0f }
 };
 // thin rect with colinear-ish lines
 const SkPoint gPoints4[] = {
     { -6.0f, -50.0f },
     { 4.0f, -50.0f },
     { 5.0f, -25.0f },
     { 6.0f,   0.0f },
     { 5.0f,  25.0f },
     { 4.0f,  50.0f },
     { -4.0f,  50.0f }
 };
 // degenerate
 const SkPoint gPoints5[] = {
     { -0.025f, -0.025f },
     { 0.025f, -0.025f },
     { 0.025f,  0.025f },
     { -0.025f,  0.025f }
 };
 // Triangle in which the first point should fuse with last
 const SkPoint gPoints6[] = {
     { -20.0f, -13.0f },
     { -20.0f, -13.05f },
     { 20.0f, -13.0f },
     { 20.0f,  27.0f }
 };
 // thin rect with colinear lines
 const SkPoint gPoints7[] = {
     { -10.0f, -50.0f },
     { 10.0f, -50.0f },
     { 10.0f, -25.0f },
     { 10.0f,   0.0f },
     { 10.0f,  25.0f },
     { 10.0f,  50.0f },
     { -10.0f,  50.0f }
 };
 // capped teardrop
 const SkPoint gPoints8[] = {
     { 50.00f,  50.00f },
     { 0.00f,  50.00f },
     { -15.45f,  47.55f },
     { -29.39f,  40.45f },
     { -40.45f,  29.39f },
     { -47.55f,  15.45f },
     { -50.00f,   0.00f },
     { -47.55f, -15.45f },
     { -40.45f, -29.39f },
     { -29.39f, -40.45f },
     { -15.45f, -47.55f },
     { 0.00f, -50.00f },
     { 50.00f, -50.00f }
 };
 // teardrop
 const SkPoint gPoints9[] = {
     { 4.39f,  40.45f },
     { -9.55f,  47.55f },
     { -25.00f,  50.00f },
     { -40.45f,  47.55f },
     { -54.39f,  40.45f },
     { -65.45f,  29.39f },
     { -72.55f,  15.45f },
     { -75.00f,   0.00f },
     { -72.55f, -15.45f },
     { -65.45f, -29.39f },
     { -54.39f, -40.45f },
     { -40.45f, -47.55f },
     { -25.0f,  -50.0f },
     { -9.55f, -47.55f },
     { 4.39f, -40.45f },
     { 75.00f,   0.00f }
 };
 // clipped triangle
 const SkPoint gPoints10[] = {
     { -10.0f, -50.0f },
     { 10.0f, -50.0f },
     { 50.0f,  31.0f },
     { 40.0f,  50.0f },
     { -40.0f,  50.0f },
     { -50.0f,  31.0f },
 };

 const SkPoint* gPoints[] = {
     gPoints0, gPoints1, gPoints2, gPoints3, gPoints4, gPoints5, gPoints6,
     gPoints7, gPoints8, gPoints9, gPoints10,
 };

 const size_t gSizes[] = {
     SK_ARRAY_COUNT(gPoints0),
     SK_ARRAY_COUNT(gPoints1),
     SK_ARRAY_COUNT(gPoints2),
     SK_ARRAY_COUNT(gPoints3),
     SK_ARRAY_COUNT(gPoints4),
     SK_ARRAY_COUNT(gPoints5),
     SK_ARRAY_COUNT(gPoints6),
     SK_ARRAY_COUNT(gPoints7),
     SK_ARRAY_COUNT(gPoints8),
     SK_ARRAY_COUNT(gPoints9),
     SK_ARRAY_COUNT(gPoints10),
 };
 static_assert(SK_ARRAY_COUNT(gSizes) == SK_ARRAY_COUNT(gPoints), "array_mismatch");
 }

 namespace skiagm {

 // This GM is intended to exercise Ganesh's handling of convex line-only
 // paths
 class ConvexLineOnlyPathsGM : public GM {
 public:
     ConvexLineOnlyPathsGM(bool doStrokeAndFill) : fDoStrokeAndFill(doStrokeAndFill) {
         this->setBGColor(0xFFFFFFFF);
     }

 protected:
     SkString onShortName() override {
         if (fDoStrokeAndFill) {
             return SkString("convex-lineonly-paths-stroke-and-fill");
         }
         return SkString("convex-lineonly-paths");
     }
     SkISize onISize() override { return SkISize::Make(kGMWidth, kGMHeight); }
     bool runAsBench() const override { return true; }

     static SkPath GetPath(int index, SkPath::Direction dir) {
         std::unique_ptr<SkPoint[]> data(nullptr);
         const SkPoint* points;
         int numPts;
         if (index < (int) SK_ARRAY_COUNT(ConvexLineOnlyData::gPoints)) {
             // manually specified
             points = ConvexLineOnlyData::gPoints[index];
             numPts = (int)ConvexLineOnlyData::gSizes[index];
         } else {
             // procedurally generated
             SkScalar width = kMaxPathHeight/2;
             SkScalar height = kMaxPathHeight/2;
             switch (index-SK_ARRAY_COUNT(ConvexLineOnlyData::gPoints)) {
             case 0:
                 numPts = 3;
                 break;
             case 1:
                 numPts = 4;
                 break;
             case 2:
                 numPts = 5;
                 break;
             case 3:             // squashed pentagon
                 numPts = 5;
                 width = kMaxPathHeight/5;
                 break;
             case 4:
                 numPts = 6;
                 break;
             case 5:
                 numPts = 8;
                 break;
             case 6:              // squashed octogon
                 numPts = 8;
                 width = kMaxPathHeight/5;
                 break;
             case 7:
                 numPts = 20;
                 break;
             case 8:
                 numPts = 100;
                 break;
             default:
                 numPts = 3;
                 break;
             }

             data.reset(new SkPoint[numPts]);

             create_ngon(numPts, data.get(), width, height);
             points = data.get();
         }

         SkPath path;

         if (SkPath::kCW_Direction == dir) {
             path.moveTo(points[0]);
             for (int i = 1; i < numPts; ++i) {
                 path.lineTo(points[i]);
             }
         } else {
             path.moveTo(points[numPts-1]);
             for (int i = numPts-2; i >= 0; --i) {
                 path.lineTo(points[i]);
             }
         }

         path.close();
 #ifdef SK_DEBUG
         // Each path this method returns should be convex, only composed of
         // lines, wound the right direction, and short enough to fit in one
         // of the GMs rows.
         SkASSERT(path.isConvex());
         SkASSERT(SkPath::kLine_SegmentMask == path.getSegmentMasks());
         SkPathPriv::FirstDirection actualDir;
         SkASSERT(SkPathPriv::CheapComputeFirstDirection(path, &actualDir));
         SkASSERT(SkPathPriv::AsFirstDirection(dir) == actualDir);
         SkRect bounds = path.getBounds();
         SkASSERT(SkScalarNearlyEqual(bounds.centerX(), 0.0f));
         SkASSERT(bounds.height() <= kMaxPathHeight);
 #endif
         return path;
     }

     // Draw a single path several times, shrinking it, flipping its direction
     // and changing its start vertex each time.
     void drawPath(SkCanvas* canvas, int index, SkPoint* offset) {

         SkPoint center;
         {
             SkPath path = GetPath(index, SkPath::kCW_Direction);
             if (offset->fX+path.getBounds().width() > kGMWidth) {
                 offset->fX = 0;
                 offset->fY += kMaxPathHeight;
                 if (fDoStrokeAndFill) {
                     offset->fX += kStrokeWidth / 2.0f;
                     offset->fY += kStrokeWidth / 2.0f;
                 }
             }
             center = { offset->fX + SkScalarHalf(path.getBounds().width()), offset->fY};
             offset->fX += path.getBounds().width();
             if (fDoStrokeAndFill) {
                 offset->fX += kStrokeWidth;
             }
         }

         const SkColor colors[2] = { SK_ColorBLACK, SK_ColorWHITE };
         const SkPath::Direction dirs[2] = { SkPath::kCW_Direction, SkPath::kCCW_Direction };
         const float scales[] = { 1.0f, 0.75f, 0.5f, 0.25f, 0.1f, 0.01f, 0.001f };
         const SkPaint::Join joins[3] = { SkPaint::kRound_Join,
                                          SkPaint::kBevel_Join,
                                          SkPaint::kMiter_Join };

         SkPaint paint;
         paint.setAntiAlias(true);

         for (size_t i = 0; i < SK_ARRAY_COUNT(scales); ++i) {
             SkPath path = GetPath(index, dirs[i%2]);
             if (fDoStrokeAndFill) {
                 paint.setStyle(SkPaint::kStrokeAndFill_Style);
                 paint.setStrokeJoin(joins[i%3]);
                 paint.setStrokeWidth(SkIntToScalar(kStrokeWidth));
             }

             canvas->save();
                 canvas->translate(center.fX, center.fY);
                 canvas->scale(scales[i], scales[i]);
                 paint.setColor(colors[i%2]);
                 canvas->drawPath(path, paint);
             canvas->restore();
         }
     }

     void onDraw(SkCanvas* canvas) override {
         // the right edge of the last drawn path
         SkPoint offset = { 0, SkScalarHalf(kMaxPathHeight) };
         if (fDoStrokeAndFill) {
             offset.fX += kStrokeWidth / 2.0f;
             offset.fY += kStrokeWidth / 2.0f;
         }

         for (int i = 0; i < kNumPaths; ++i) {
             this->drawPath(canvas, i, &offset);
         }

         // Repro for crbug.com/472723 (Missing AA on portions of graphic with GPU rasterization)
         {
             canvas->translate(356.0f, 50.0f);

             SkPaint p;
             p.setAntiAlias(true);
             if (fDoStrokeAndFill) {
                 p.setStyle(SkPaint::kStrokeAndFill_Style);
                 p.setStrokeJoin(SkPaint::kMiter_Join);
                 p.setStrokeWidth(SkIntToScalar(kStrokeWidth));
             }

             SkPath p1;
             p1.moveTo(60.8522949f, 364.671021f);
             p1.lineTo(59.4380493f, 364.671021f);
             p1.lineTo(385.414276f, 690.647217f);
             p1.lineTo(386.121399f, 689.940125f);
             canvas->drawPath(p1, p);
         }
     }

 private:
     static constexpr int kStrokeWidth   = 10;
     static constexpr int kNumPaths      = 20;
     static constexpr int kMaxPathHeight = 100;
     static constexpr int kGMWidth       = 512;
     static constexpr int kGMHeight      = 512;

     bool fDoStrokeAndFill;

     typedef GM INHERITED;
 };

 //////////////////////////////////////////////////////////////////////////////

 DEF_GM(return new ConvexLineOnlyPathsGM(false);)
 DEF_GM(return new ConvexLineOnlyPathsGM(true);)
 }
	/*
	* 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 "gm.h"
	#include "SkPolyUtils.h"
	#include "SkPathPriv.h"

	static void create_ngon(int n, SkPoint* pts, SkScalar width, SkScalar height) {
	float angleStep = 360.0f / n, angle = 0.0f, sin, cos;
	if ((n % 2) == 1) {
	angle = angleStep/2.0f;
	}

	for (int i = 0; i < n; ++i) {
	sin = SkScalarSinCos(SkDegreesToRadians(angle), &cos);
	pts[i].fX = -sin * width;
	pts[i].fY = cos * height;
	angle += angleStep;
	}
	}

	namespace ConvexLineOnlyData {
	// narrow rect
	const SkPoint gPoints0[] = {
	{ -1.5f, -50.0f },
	{ 1.5f, -50.0f },
	{ 1.5f, 50.0f },
	{ -1.5f, 50.0f }
	};
	// narrow rect on an angle
	const SkPoint gPoints1[] = {
	{ -50.0f, -49.0f },
	{ -49.0f, -50.0f },
	{ 50.0f, 49.0f },
	{ 49.0f, 50.0f }
	};
	// trap - narrow on top - wide on bottom
	const SkPoint gPoints2[] = {
	{ -10.0f, -50.0f },
	{ 10.0f, -50.0f },
	{ 50.0f, 50.0f },
	{ -50.0f, 50.0f }
	};
	// wide skewed rect
	const SkPoint gPoints3[] = {
	{ -50.0f, -50.0f },
	{ 0.0f, -50.0f },
	{ 50.0f, 50.0f },
	{ 0.0f, 50.0f }
	};
	// thin rect with colinear-ish lines
	const SkPoint gPoints4[] = {
	{ -6.0f, -50.0f },
	{ 4.0f, -50.0f },
	{ 5.0f, -25.0f },
	{ 6.0f, 0.0f },
	{ 5.0f, 25.0f },
	{ 4.0f, 50.0f },
	{ -4.0f, 50.0f }
	};
	// degenerate
	const SkPoint gPoints5[] = {
	{ -0.025f, -0.025f },
	{ 0.025f, -0.025f },
	{ 0.025f, 0.025f },
	{ -0.025f, 0.025f }
	};
	// Triangle in which the first point should fuse with last
	const SkPoint gPoints6[] = {
	{ -20.0f, -13.0f },
	{ -20.0f, -13.05f },
	{ 20.0f, -13.0f },
	{ 20.0f, 27.0f }
	};
	// thin rect with colinear lines
	const SkPoint gPoints7[] = {
	{ -10.0f, -50.0f },
	{ 10.0f, -50.0f },
	{ 10.0f, -25.0f },
	{ 10.0f, 0.0f },
	{ 10.0f, 25.0f },
	{ 10.0f, 50.0f },
	{ -10.0f, 50.0f }
	};
	// capped teardrop
	const SkPoint gPoints8[] = {
	{ 50.00f, 50.00f },
	{ 0.00f, 50.00f },
	{ -15.45f, 47.55f },
	{ -29.39f, 40.45f },
	{ -40.45f, 29.39f },
	{ -47.55f, 15.45f },
	{ -50.00f, 0.00f },
	{ -47.55f, -15.45f },
	{ -40.45f, -29.39f },
	{ -29.39f, -40.45f },
	{ -15.45f, -47.55f },
	{ 0.00f, -50.00f },
	{ 50.00f, -50.00f }
	};
	// teardrop
	const SkPoint gPoints9[] = {
	{ 4.39f, 40.45f },
	{ -9.55f, 47.55f },
	{ -25.00f, 50.00f },
	{ -40.45f, 47.55f },
	{ -54.39f, 40.45f },
	{ -65.45f, 29.39f },
	{ -72.55f, 15.45f },
	{ -75.00f, 0.00f },
	{ -72.55f, -15.45f },
	{ -65.45f, -29.39f },
	{ -54.39f, -40.45f },
	{ -40.45f, -47.55f },
	{ -25.0f, -50.0f },
	{ -9.55f, -47.55f },
	{ 4.39f, -40.45f },
	{ 75.00f, 0.00f }
	};
	// clipped triangle
	const SkPoint gPoints10[] = {
	{ -10.0f, -50.0f },
	{ 10.0f, -50.0f },
	{ 50.0f, 31.0f },
	{ 40.0f, 50.0f },
	{ -40.0f, 50.0f },
	{ -50.0f, 31.0f },
	};

	const SkPoint* gPoints[] = {
	gPoints0, gPoints1, gPoints2, gPoints3, gPoints4, gPoints5, gPoints6,
	gPoints7, gPoints8, gPoints9, gPoints10,
	};

	const size_t gSizes[] = {
	SK_ARRAY_COUNT(gPoints0),
	SK_ARRAY_COUNT(gPoints1),
	SK_ARRAY_COUNT(gPoints2),
	SK_ARRAY_COUNT(gPoints3),
	SK_ARRAY_COUNT(gPoints4),
	SK_ARRAY_COUNT(gPoints5),
	SK_ARRAY_COUNT(gPoints6),
	SK_ARRAY_COUNT(gPoints7),
	SK_ARRAY_COUNT(gPoints8),
	SK_ARRAY_COUNT(gPoints9),
	SK_ARRAY_COUNT(gPoints10),
	};
	static_assert(SK_ARRAY_COUNT(gSizes) == SK_ARRAY_COUNT(gPoints), "array_mismatch");
	}

	namespace skiagm {

	// This GM is intended to exercise Ganesh's handling of convex line-only
	// paths
	class ConvexLineOnlyPathsGM : public GM {
	public:
	ConvexLineOnlyPathsGM(bool doStrokeAndFill) : fDoStrokeAndFill(doStrokeAndFill) {
	this->setBGColor(0xFFFFFFFF);
	}

	protected:
	SkString onShortName() override {
	if (fDoStrokeAndFill) {
	return SkString("convex-lineonly-paths-stroke-and-fill");
	}
	return SkString("convex-lineonly-paths");
	}
	SkISize onISize() override { return SkISize::Make(kGMWidth, kGMHeight); }
	bool runAsBench() const override { return true; }

	static SkPath GetPath(int index, SkPath::Direction dir) {
	std::unique_ptr<SkPoint[]> data(nullptr);
	const SkPoint* points;
	int numPts;
	if (index < (int) SK_ARRAY_COUNT(ConvexLineOnlyData::gPoints)) {
	// manually specified
	points = ConvexLineOnlyData::gPoints[index];
	numPts = (int)ConvexLineOnlyData::gSizes[index];
	} else {
	// procedurally generated
	SkScalar width = kMaxPathHeight/2;
	SkScalar height = kMaxPathHeight/2;
	switch (index-SK_ARRAY_COUNT(ConvexLineOnlyData::gPoints)) {
	case 0:
	numPts = 3;
	break;
	case 1:
	numPts = 4;
	break;
	case 2:
	numPts = 5;
	break;
	case 3: // squashed pentagon
	numPts = 5;
	width = kMaxPathHeight/5;
	break;
	case 4:
	numPts = 6;
	break;
	case 5:
	numPts = 8;
	break;
	case 6: // squashed octogon
	numPts = 8;
	width = kMaxPathHeight/5;
	break;
	case 7:
	numPts = 20;
	break;
	case 8:
	numPts = 100;
	break;
	default:
	numPts = 3;
	break;
	}

	data.reset(new SkPoint[numPts]);

	create_ngon(numPts, data.get(), width, height);
	points = data.get();
	}

	SkPath path;

	if (SkPath::kCW_Direction == dir) {
	path.moveTo(points[0]);
	for (int i = 1; i < numPts; ++i) {
	path.lineTo(points[i]);
	}
	} else {
	path.moveTo(points[numPts-1]);
	for (int i = numPts-2; i >= 0; --i) {
	path.lineTo(points[i]);
	}
	}

	path.close();
	#ifdef SK_DEBUG
	// Each path this method returns should be convex, only composed of
	// lines, wound the right direction, and short enough to fit in one
	// of the GMs rows.
	SkASSERT(path.isConvex());
	SkASSERT(SkPath::kLine_SegmentMask == path.getSegmentMasks());
	SkPathPriv::FirstDirection actualDir;
	SkASSERT(SkPathPriv::CheapComputeFirstDirection(path, &actualDir));
	SkASSERT(SkPathPriv::AsFirstDirection(dir) == actualDir);
	SkRect bounds = path.getBounds();
	SkASSERT(SkScalarNearlyEqual(bounds.centerX(), 0.0f));
	SkASSERT(bounds.height() <= kMaxPathHeight);
	#endif
	return path;
	}

	// Draw a single path several times, shrinking it, flipping its direction
	// and changing its start vertex each time.
	void drawPath(SkCanvas* canvas, int index, SkPoint* offset) {

	SkPoint center;
	{
	SkPath path = GetPath(index, SkPath::kCW_Direction);
	if (offset->fX+path.getBounds().width() > kGMWidth) {
	offset->fX = 0;
	offset->fY += kMaxPathHeight;
	if (fDoStrokeAndFill) {
	offset->fX += kStrokeWidth / 2.0f;
	offset->fY += kStrokeWidth / 2.0f;
	}
	}
	center = { offset->fX + SkScalarHalf(path.getBounds().width()), offset->fY};
	offset->fX += path.getBounds().width();
	if (fDoStrokeAndFill) {
	offset->fX += kStrokeWidth;
	}
	}

	const SkColor colors[2] = { SK_ColorBLACK, SK_ColorWHITE };
	const SkPath::Direction dirs[2] = { SkPath::kCW_Direction, SkPath::kCCW_Direction };
	const float scales[] = { 1.0f, 0.75f, 0.5f, 0.25f, 0.1f, 0.01f, 0.001f };
	const SkPaint::Join joins[3] = { SkPaint::kRound_Join,
	SkPaint::kBevel_Join,
	SkPaint::kMiter_Join };

	SkPaint paint;
	paint.setAntiAlias(true);

	for (size_t i = 0; i < SK_ARRAY_COUNT(scales); ++i) {
	SkPath path = GetPath(index, dirs[i%2]);
	if (fDoStrokeAndFill) {
	paint.setStyle(SkPaint::kStrokeAndFill_Style);
	paint.setStrokeJoin(joins[i%3]);
	paint.setStrokeWidth(SkIntToScalar(kStrokeWidth));
	}

	canvas->save();
	canvas->translate(center.fX, center.fY);
	canvas->scale(scales[i], scales[i]);
	paint.setColor(colors[i%2]);
	canvas->drawPath(path, paint);
	canvas->restore();
	}
	}

	void onDraw(SkCanvas* canvas) override {
	// the right edge of the last drawn path
	SkPoint offset = { 0, SkScalarHalf(kMaxPathHeight) };
	if (fDoStrokeAndFill) {
	offset.fX += kStrokeWidth / 2.0f;
	offset.fY += kStrokeWidth / 2.0f;
	}

	for (int i = 0; i < kNumPaths; ++i) {
	this->drawPath(canvas, i, &offset);
	}

	// Repro for crbug.com/472723 (Missing AA on portions of graphic with GPU rasterization)
	{
	canvas->translate(356.0f, 50.0f);

	SkPaint p;
	p.setAntiAlias(true);
	if (fDoStrokeAndFill) {
	p.setStyle(SkPaint::kStrokeAndFill_Style);
	p.setStrokeJoin(SkPaint::kMiter_Join);
	p.setStrokeWidth(SkIntToScalar(kStrokeWidth));
	}

	SkPath p1;
	p1.moveTo(60.8522949f, 364.671021f);
	p1.lineTo(59.4380493f, 364.671021f);
	p1.lineTo(385.414276f, 690.647217f);
	p1.lineTo(386.121399f, 689.940125f);
	canvas->drawPath(p1, p);
	}
	}

	private:
	static constexpr int kStrokeWidth = 10;
	static constexpr int kNumPaths = 20;
	static constexpr int kMaxPathHeight = 100;
	static constexpr int kGMWidth = 512;
	static constexpr int kGMHeight = 512;

	bool fDoStrokeAndFill;

	typedef GM INHERITED;
	};

	//////////////////////////////////////////////////////////////////////////////

	DEF_GM(return new ConvexLineOnlyPathsGM(false);)
	DEF_GM(return new ConvexLineOnlyPathsGM(true);)
	}