tests/DrawPathTest.cpp - skia - Git at Google

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkDashPathEffect.h"
 #include "SkSurface.h"
 #include "Test.h"

 // test that we can draw an aa-rect at coordinates > 32K (bigger than fixedpoint)
 static void test_big_aa_rect(skiatest::Reporter* reporter) {
     SkBitmap output;
     SkPMColor pixel[1];
     output.installPixels(SkImageInfo::MakeN32Premul(1, 1), pixel, 4);

     SkSurface* surf = SkSurface::NewRasterPMColor(300, 33300);
     SkCanvas* canvas = surf->getCanvas();

     SkRect r = { 0, 33000, 300, 33300 };
     int x = SkScalarRoundToInt(r.left());
     int y = SkScalarRoundToInt(r.top());

     // check that the pixel in question starts as transparent (by the surface)
     if (canvas->readPixels(&output, x, y)) {
         REPORTER_ASSERT(reporter, 0 == pixel[0]);
     } else {
         REPORTER_ASSERT_MESSAGE(reporter, false, "readPixels failed");
     }

     SkPaint paint;
     paint.setAntiAlias(true);
     paint.setColor(SK_ColorWHITE);

     canvas->drawRect(r, paint);

     // Now check that it is BLACK
     if (canvas->readPixels(&output, x, y)) {
         // don't know what swizzling PMColor did, but white should always
         // appear the same.
         REPORTER_ASSERT(reporter, 0xFFFFFFFF == pixel[0]);
     } else {
         REPORTER_ASSERT_MESSAGE(reporter, false, "readPixels failed");
     }
     surf->unref();
 }

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

 static void moveToH(SkPath* path, const uint32_t raw[]) {
     const float* fptr = (const float*)raw;
     path->moveTo(fptr[0], fptr[1]);
 }

 static void cubicToH(SkPath* path, const uint32_t raw[]) {
     const float* fptr = (const float*)raw;
     path->cubicTo(fptr[0], fptr[1], fptr[2], fptr[3], fptr[4], fptr[5]);
 }

 // This used to assert, because we performed a cast (int)(pt[0].fX * scale) to
 // arrive at an int (SkFDot6) rather than calling sk_float_round2int. The assert
 // was that the initial line-segment produced by the cubic was not monotonically
 // going down (i.e. the initial DY was negative). By rounding the floats, we get
 // the more proper result.
 //
 // http://code.google.com/p/chromium/issues/detail?id=131181
 //

 // we're not calling this test anymore; is that for a reason?

 static void test_crbug131181() {
     /*
      fX = 18.8943768,
      fY = 129.121277
      }, {
      fX = 18.8937435,
      fY = 129.121689
      }, {
      fX = 18.8950119,
      fY = 129.120422
      }, {
      fX = 18.5030727,
      fY = 129.13121
      */
     uint32_t data[] = {
         0x419727af, 0x43011f0c, 0x41972663, 0x43011f27,
         0x419728fc, 0x43011ed4, 0x4194064b, 0x43012197
     };

     SkPath path;
     moveToH(&path, &data[0]);
     cubicToH(&path, &data[2]);

     SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(640, 480));

     SkPaint paint;
     paint.setAntiAlias(true);
     canvas->drawPath(path, paint);
 }

 // This used to assert in debug builds (and crash writing bad memory in release)
 // because we overflowed an intermediate value (B coefficient) setting up our
 // stepper for the quadratic. Now we bias that value by 1/2 so we don't overflow
 static void test_crbug_140803() {
     SkBitmap bm;
     bm.allocN32Pixels(2700, 30*1024);
     SkCanvas canvas(bm);

     SkPath path;
     path.moveTo(2762, 20);
     path.quadTo(11, 21702, 10, 21706);
     SkPaint paint;
     paint.setAntiAlias(true);
     canvas.drawPath(path, paint);
 }

 // Need to exercise drawing an inverse-path whose bounds intersect the clip,
 // but whose edges do not (since its a quad which draws only in the bottom half
 // of its bounds).
 // In the debug build, we used to assert in this case, until it was fixed.
 //
 static void test_inversepathwithclip() {
     SkPath path;

     path.moveTo(0, SkIntToScalar(20));
     path.quadTo(SkIntToScalar(10), SkIntToScalar(10),
                 SkIntToScalar(20), SkIntToScalar(20));
     path.toggleInverseFillType();

     SkPaint paint;

     SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(640, 480));
     canvas.get()->save();
     canvas.get()->clipRect(SkRect::MakeWH(SkIntToScalar(19), SkIntToScalar(11)));

     paint.setAntiAlias(false);
     canvas.get()->drawPath(path, paint);
     paint.setAntiAlias(true);
     canvas.get()->drawPath(path, paint);

     canvas.get()->restore();

     // Now do the test again, with the path flipped, so we only draw in the
     // top half of our bounds, and have the clip intersect our bounds at the
     // bottom.
     path.reset();   // preserves our filltype
     path.moveTo(0, SkIntToScalar(10));
     path.quadTo(SkIntToScalar(10), SkIntToScalar(20),
                 SkIntToScalar(20), SkIntToScalar(10));
     canvas.get()->clipRect(SkRect::MakeXYWH(SkIntToScalar(0), SkIntToScalar(19),
                                             SkIntToScalar(19), SkIntToScalar(11)));

     paint.setAntiAlias(false);
     canvas.get()->drawPath(path, paint);
     paint.setAntiAlias(true);
     canvas.get()->drawPath(path, paint);
 }

 static void test_bug533() {
     /*
         http://code.google.com/p/skia/issues/detail?id=533
         This particular test/bug only applies to the float case, where the
         coordinates are very large.
      */
     SkPath path;
     path.moveTo(64, 3);
     path.quadTo(-329936, -100000000, 1153, 330003);

     SkPaint paint;
     paint.setAntiAlias(true);

     SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(640, 480));
     canvas.get()->drawPath(path, paint);
 }

 static void test_crbug_140642() {
     /*
      *  We used to see this construct, and due to rounding as we accumulated
      *  our length, the loop where we apply the phase would run off the end of
      *  the array, since it relied on just -= each interval value, which did not
      *  behave as "expected". Now the code explicitly checks for walking off the
      *  end of that array.

      *  A different (better) fix might be to rewrite dashing to do all of its
      *  length/phase/measure math using double, but this may need to be
      *  coordinated with SkPathMeasure, to be consistent between the two.

      <path stroke="mintcream" stroke-dasharray="27734 35660 2157846850 247"
            stroke-dashoffset="-248.135982067">
      */

     const SkScalar vals[] = { 27734, 35660, 2157846850.0f, 247 };
     SkAutoTUnref<SkDashPathEffect> dontAssert(SkDashPathEffect::Create(vals, 4, -248.135982067f));
 }

 static void test_crbug_124652() {
     /*
         http://code.google.com/p/chromium/issues/detail?id=124652
         This particular test/bug only applies to the float case, where
         large values can "swamp" small ones.
      */
     SkScalar intervals[2] = {837099584, 33450};
     SkAutoTUnref<SkDashPathEffect> dash(SkDashPathEffect::Create(intervals, 2, -10));
 }

 static void test_bigcubic() {
     SkPath path;
     path.moveTo(64, 3);
     path.cubicTo(-329936, -100000000, -329936, 100000000, 1153, 330003);

     SkPaint paint;
     paint.setAntiAlias(true);

     SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(640, 480));
     canvas.get()->drawPath(path, paint);
 }

 // we used to assert if the bounds of the device (clip) was larger than 32K
 // even when the path itself was smaller. We just draw and hope in the debug
 // version to not assert.
 static void test_giantaa() {
     const int W = 400;
     const int H = 400;
     SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(33000, 10));

     SkPaint paint;
     paint.setAntiAlias(true);
     SkPath path;
     path.addOval(SkRect::MakeXYWH(-10, -10, 20 + W, 20 + H));
     canvas.get()->drawPath(path, paint);
 }

 // Extremely large path_length/dash_length ratios may cause infinite looping
 // in SkDashPathEffect::filterPath() due to single precision rounding.
 // The test is quite expensive, but it should get much faster after the fix
 // for http://crbug.com/165432 goes in.
 static void test_infinite_dash(skiatest::Reporter* reporter) {
     SkPath path;
     path.moveTo(0, 0);
     path.lineTo(5000000, 0);

     SkScalar intervals[] = { 0.2f, 0.2f };
     SkAutoTUnref<SkDashPathEffect> dash(SkDashPathEffect::Create(intervals, 2, 0));

     SkPath filteredPath;
     SkPaint paint;
     paint.setStyle(SkPaint::kStroke_Style);
     paint.setPathEffect(dash);

     paint.getFillPath(path, &filteredPath);
     // If we reach this, we passed.
     REPORTER_ASSERT(reporter, true);
 }

 // http://crbug.com/165432
 // Limit extreme dash path effects to avoid exhausting the system memory.
 static void test_crbug_165432(skiatest::Reporter* reporter) {
     SkPath path;
     path.moveTo(0, 0);
     path.lineTo(10000000, 0);

     SkScalar intervals[] = { 0.5f, 0.5f };
     SkAutoTUnref<SkDashPathEffect> dash(SkDashPathEffect::Create(intervals, 2, 0));

     SkPaint paint;
     paint.setStyle(SkPaint::kStroke_Style);
     paint.setPathEffect(dash);

     SkPath filteredPath;
     SkStrokeRec rec(paint);
     REPORTER_ASSERT(reporter, !dash->filterPath(&filteredPath, path, &rec, NULL));
     REPORTER_ASSERT(reporter, filteredPath.isEmpty());
 }

 DEF_TEST(DrawPath, reporter) {
     test_giantaa();
     test_bug533();
     test_bigcubic();
     test_crbug_124652();
     test_crbug_140642();
     test_crbug_140803();
     test_inversepathwithclip();
     // why?
     if (false) test_crbug131181();
     test_infinite_dash(reporter);
     test_crbug_165432(reporter);
     test_big_aa_rect(reporter);
 }
	/*
	* Copyright 2012 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "SkBitmap.h"
	#include "SkCanvas.h"
	#include "SkDashPathEffect.h"
	#include "SkSurface.h"
	#include "Test.h"

	// test that we can draw an aa-rect at coordinates > 32K (bigger than fixedpoint)
	static void test_big_aa_rect(skiatest::Reporter* reporter) {
	SkBitmap output;
	SkPMColor pixel[1];
	output.installPixels(SkImageInfo::MakeN32Premul(1, 1), pixel, 4);

	SkSurface* surf = SkSurface::NewRasterPMColor(300, 33300);
	SkCanvas* canvas = surf->getCanvas();

	SkRect r = { 0, 33000, 300, 33300 };
	int x = SkScalarRoundToInt(r.left());
	int y = SkScalarRoundToInt(r.top());

	// check that the pixel in question starts as transparent (by the surface)
	if (canvas->readPixels(&output, x, y)) {
	REPORTER_ASSERT(reporter, 0 == pixel[0]);
	} else {
	REPORTER_ASSERT_MESSAGE(reporter, false, "readPixels failed");
	}

	SkPaint paint;
	paint.setAntiAlias(true);
	paint.setColor(SK_ColorWHITE);

	canvas->drawRect(r, paint);

	// Now check that it is BLACK
	if (canvas->readPixels(&output, x, y)) {
	// don't know what swizzling PMColor did, but white should always
	// appear the same.
	REPORTER_ASSERT(reporter, 0xFFFFFFFF == pixel[0]);
	} else {
	REPORTER_ASSERT_MESSAGE(reporter, false, "readPixels failed");
	}
	surf->unref();
	}

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

	static void moveToH(SkPath* path, const uint32_t raw[]) {
	const float* fptr = (const float*)raw;
	path->moveTo(fptr[0], fptr[1]);
	}

	static void cubicToH(SkPath* path, const uint32_t raw[]) {
	const float* fptr = (const float*)raw;
	path->cubicTo(fptr[0], fptr[1], fptr[2], fptr[3], fptr[4], fptr[5]);
	}

	// This used to assert, because we performed a cast (int)(pt[0].fX * scale) to
	// arrive at an int (SkFDot6) rather than calling sk_float_round2int. The assert
	// was that the initial line-segment produced by the cubic was not monotonically
	// going down (i.e. the initial DY was negative). By rounding the floats, we get
	// the more proper result.
	//
	// http://code.google.com/p/chromium/issues/detail?id=131181
	//

	// we're not calling this test anymore; is that for a reason?

	static void test_crbug131181() {
	/*
	fX = 18.8943768,
	fY = 129.121277
	}, {
	fX = 18.8937435,
	fY = 129.121689
	}, {
	fX = 18.8950119,
	fY = 129.120422
	}, {
	fX = 18.5030727,
	fY = 129.13121
	*/
	uint32_t data[] = {
	0x419727af, 0x43011f0c, 0x41972663, 0x43011f27,
	0x419728fc, 0x43011ed4, 0x4194064b, 0x43012197
	};

	SkPath path;
	moveToH(&path, &data[0]);
	cubicToH(&path, &data[2]);

	SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(640, 480));

	SkPaint paint;
	paint.setAntiAlias(true);
	canvas->drawPath(path, paint);
	}

	// This used to assert in debug builds (and crash writing bad memory in release)
	// because we overflowed an intermediate value (B coefficient) setting up our
	// stepper for the quadratic. Now we bias that value by 1/2 so we don't overflow
	static void test_crbug_140803() {
	SkBitmap bm;
	bm.allocN32Pixels(2700, 30*1024);
	SkCanvas canvas(bm);

	SkPath path;
	path.moveTo(2762, 20);
	path.quadTo(11, 21702, 10, 21706);
	SkPaint paint;
	paint.setAntiAlias(true);
	canvas.drawPath(path, paint);
	}

	// Need to exercise drawing an inverse-path whose bounds intersect the clip,
	// but whose edges do not (since its a quad which draws only in the bottom half
	// of its bounds).
	// In the debug build, we used to assert in this case, until it was fixed.
	//
	static void test_inversepathwithclip() {
	SkPath path;

	path.moveTo(0, SkIntToScalar(20));
	path.quadTo(SkIntToScalar(10), SkIntToScalar(10),
	SkIntToScalar(20), SkIntToScalar(20));
	path.toggleInverseFillType();

	SkPaint paint;

	SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(640, 480));
	canvas.get()->save();
	canvas.get()->clipRect(SkRect::MakeWH(SkIntToScalar(19), SkIntToScalar(11)));

	paint.setAntiAlias(false);
	canvas.get()->drawPath(path, paint);
	paint.setAntiAlias(true);
	canvas.get()->drawPath(path, paint);

	canvas.get()->restore();

	// Now do the test again, with the path flipped, so we only draw in the
	// top half of our bounds, and have the clip intersect our bounds at the
	// bottom.
	path.reset(); // preserves our filltype
	path.moveTo(0, SkIntToScalar(10));
	path.quadTo(SkIntToScalar(10), SkIntToScalar(20),
	SkIntToScalar(20), SkIntToScalar(10));
	canvas.get()->clipRect(SkRect::MakeXYWH(SkIntToScalar(0), SkIntToScalar(19),
	SkIntToScalar(19), SkIntToScalar(11)));

	paint.setAntiAlias(false);
	canvas.get()->drawPath(path, paint);
	paint.setAntiAlias(true);
	canvas.get()->drawPath(path, paint);
	}

	static void test_bug533() {
	/*
	http://code.google.com/p/skia/issues/detail?id=533
	This particular test/bug only applies to the float case, where the
	coordinates are very large.
	*/
	SkPath path;
	path.moveTo(64, 3);
	path.quadTo(-329936, -100000000, 1153, 330003);

	SkPaint paint;
	paint.setAntiAlias(true);

	SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(640, 480));
	canvas.get()->drawPath(path, paint);
	}

	static void test_crbug_140642() {
	/*
	* We used to see this construct, and due to rounding as we accumulated
	* our length, the loop where we apply the phase would run off the end of
	* the array, since it relied on just -= each interval value, which did not
	* behave as "expected". Now the code explicitly checks for walking off the
	* end of that array.

	* A different (better) fix might be to rewrite dashing to do all of its
	* length/phase/measure math using double, but this may need to be
	* coordinated with SkPathMeasure, to be consistent between the two.

	<path stroke="mintcream" stroke-dasharray="27734 35660 2157846850 247"
	stroke-dashoffset="-248.135982067">
	*/

	const SkScalar vals[] = { 27734, 35660, 2157846850.0f, 247 };
	SkAutoTUnref<SkDashPathEffect> dontAssert(SkDashPathEffect::Create(vals, 4, -248.135982067f));
	}

	static void test_crbug_124652() {
	/*
	http://code.google.com/p/chromium/issues/detail?id=124652
	This particular test/bug only applies to the float case, where
	large values can "swamp" small ones.
	*/
	SkScalar intervals[2] = {837099584, 33450};
	SkAutoTUnref<SkDashPathEffect> dash(SkDashPathEffect::Create(intervals, 2, -10));
	}

	static void test_bigcubic() {
	SkPath path;
	path.moveTo(64, 3);
	path.cubicTo(-329936, -100000000, -329936, 100000000, 1153, 330003);

	SkPaint paint;
	paint.setAntiAlias(true);

	SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(640, 480));
	canvas.get()->drawPath(path, paint);
	}

	// we used to assert if the bounds of the device (clip) was larger than 32K
	// even when the path itself was smaller. We just draw and hope in the debug
	// version to not assert.
	static void test_giantaa() {
	const int W = 400;
	const int H = 400;
	SkAutoTUnref<SkCanvas> canvas(SkCanvas::NewRasterN32(33000, 10));

	SkPaint paint;
	paint.setAntiAlias(true);
	SkPath path;
	path.addOval(SkRect::MakeXYWH(-10, -10, 20 + W, 20 + H));
	canvas.get()->drawPath(path, paint);
	}

	// Extremely large path_length/dash_length ratios may cause infinite looping
	// in SkDashPathEffect::filterPath() due to single precision rounding.
	// The test is quite expensive, but it should get much faster after the fix
	// for http://crbug.com/165432 goes in.
	static void test_infinite_dash(skiatest::Reporter* reporter) {
	SkPath path;
	path.moveTo(0, 0);
	path.lineTo(5000000, 0);

	SkScalar intervals[] = { 0.2f, 0.2f };
	SkAutoTUnref<SkDashPathEffect> dash(SkDashPathEffect::Create(intervals, 2, 0));

	SkPath filteredPath;
	SkPaint paint;
	paint.setStyle(SkPaint::kStroke_Style);
	paint.setPathEffect(dash);

	paint.getFillPath(path, &filteredPath);
	// If we reach this, we passed.
	REPORTER_ASSERT(reporter, true);
	}

	// http://crbug.com/165432
	// Limit extreme dash path effects to avoid exhausting the system memory.
	static void test_crbug_165432(skiatest::Reporter* reporter) {
	SkPath path;
	path.moveTo(0, 0);
	path.lineTo(10000000, 0);

	SkScalar intervals[] = { 0.5f, 0.5f };
	SkAutoTUnref<SkDashPathEffect> dash(SkDashPathEffect::Create(intervals, 2, 0));

	SkPaint paint;
	paint.setStyle(SkPaint::kStroke_Style);
	paint.setPathEffect(dash);

	SkPath filteredPath;
	SkStrokeRec rec(paint);
	REPORTER_ASSERT(reporter, !dash->filterPath(&filteredPath, path, &rec, NULL));
	REPORTER_ASSERT(reporter, filteredPath.isEmpty());
	}

	DEF_TEST(DrawPath, reporter) {
	test_giantaa();
	test_bug533();
	test_bigcubic();
	test_crbug_124652();
	test_crbug_140642();
	test_crbug_140803();
	test_inversepathwithclip();
	// why?
	if (false) test_crbug131181();
	test_infinite_dash(reporter);
	test_crbug_165432(reporter);
	test_big_aa_rect(reporter);
	}