skia2/gm/pathfill.cpp

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Automatic update of all copyright notices to reflect new license terms. I have manually examined all of these diffs and restored a few files that seem to require manual adjustment. The following files still need to be modified manually, in a separate CL: android_sample/SampleApp/AndroidManifest.xml android_sample/SampleApp/res/layout/layout.xml android_sample/SampleApp/res/menu/sample.xml android_sample/SampleApp/res/values/strings.xml android_sample/SampleApp/src/com/skia/sampleapp/SampleApp.java android_sample/SampleApp/src/com/skia/sampleapp/SampleView.java experimental/CiCarbonSampleMain.c experimental/CocoaDebugger/main.m experimental/FileReaderApp/main.m experimental/SimpleCocoaApp/main.m experimental/iOSSampleApp/Shared/SkAlertPrompt.h experimental/iOSSampleApp/Shared/SkAlertPrompt.m experimental/iOSSampleApp/SkiOSSampleApp-Base.xcconfig experimental/iOSSampleApp/SkiOSSampleApp-Debug.xcconfig experimental/iOSSampleApp/SkiOSSampleApp-Release.xcconfig gpu/src/android/GrGLDefaultInterface_android.cpp gyp/common.gypi gyp_skia include/ports/SkHarfBuzzFont.h include/views/SkOSWindow_wxwidgets.h make.bat make.py src/opts/memset.arm.S src/opts/memset16_neon.S src/opts/memset32_neon.S src/opts/opts_check_arm.cpp src/ports/SkDebug_brew.cpp src/ports/SkMemory_brew.cpp src/ports/SkOSFile_brew.cpp src/ports/SkXMLParser_empty.cpp src/utils/ios/SkImageDecoder_iOS.mm src/utils/ios/SkOSFile_iOS.mm src/utils/ios/SkStream_NSData.mm tests/FillPathTest.cpp Review URL: http://codereview.appspot.com/4816058 git-svn-id: http://skia.googlecode.com/svn/trunk@1982 2bbb7eff-a529-9590-31e7-b0007b416f81
2011-07-28 14:26:00 +00:00
/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm/gm.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPathBuilder.h"
#include "include/core/SkRect.h"
#include "include/core/SkScalar.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/core/SkTypes.h"
namespace {
struct PathDY {
SkPath path;
SkScalar dy;
};
}
typedef PathDY (*MakePathProc)();
static PathDY make_frame() {
SkRect r = { SkIntToScalar(10), SkIntToScalar(10),
SkIntToScalar(630), SkIntToScalar(470) };
SkPath path = SkPath::RRect(SkRRect::MakeRectXY(r, 15, 15));
SkPaint paint;
paint.setStyle(SkPaint::kStroke_Style);
paint.setStrokeWidth(SkIntToScalar(5));
paint.getFillPath(path, &path);
return {path, 15};
}
static PathDY make_triangle() {
constexpr int gCoord[] = {
10, 20, 15, 5, 30, 30
};
return {
SkPathBuilder().moveTo(SkIntToScalar(gCoord[0]), SkIntToScalar(gCoord[1]))
.lineTo(SkIntToScalar(gCoord[2]), SkIntToScalar(gCoord[3]))
.lineTo(SkIntToScalar(gCoord[4]), SkIntToScalar(gCoord[5]))
.close()
.offset(10, 0)
.detach(),
30
};
}
static PathDY make_rect() {
SkRect r = { SkIntToScalar(10), SkIntToScalar(10),
SkIntToScalar(30), SkIntToScalar(30) };
return {
SkPathBuilder().addRect(r).offset(10, 0).detach(),
30
};
}
static PathDY make_oval() {
SkRect r = { SkIntToScalar(10), SkIntToScalar(10),
SkIntToScalar(30), SkIntToScalar(30) };
return {
SkPathBuilder().addOval(r).offset(10, 0).detach(),
30
};
}
static PathDY make_sawtooth(int teeth) {
SkScalar x = SkIntToScalar(20);
SkScalar y = SkIntToScalar(20);
const SkScalar x0 = x;
const SkScalar dx = SkIntToScalar(5);
const SkScalar dy = SkIntToScalar(10);
SkPathBuilder builder;
builder.moveTo(x, y);
for (int i = 0; i < teeth; i++) {
x += dx;
builder.lineTo(x, y - dy);
x += dx;
builder.lineTo(x, y + dy);
}
builder.lineTo(x, y + (2 * dy));
builder.lineTo(x0, y + (2 * dy));
builder.close();
return {builder.detach(), 30};
}
static PathDY make_sawtooth_3() { return make_sawtooth(3); }
static PathDY make_sawtooth_32() { return make_sawtooth(32); }
static PathDY make_house() {
SkPathBuilder builder;
builder.addPolygon({
{21, 23},
{21, 11.534f},
{22.327f, 12.741f},
{23.673f, 11.261f},
{12, 0.648f},
{8, 4.285f},
{8, 2},
{4, 2},
{4, 7.921f},
{0.327f, 11.26f},
{1.673f, 12.74f},
{3, 11.534f},
{3, 23},
{11, 23},
{11, 18},
{13, 18},
{13, 23},
{21, 23}}, true)
.polylineTo({
{9, 16},
{9, 21},
{5, 21},
{5, 9.715f},
{12, 3.351f},
{19, 9.715f},
{19, 21},
{15, 21},
{15, 16},
{9, 16}})
.close()
.offset(20, 0);
return {builder.detach(), 30};
}
static PathDY make_star(int n) {
const SkScalar c = SkIntToScalar(45);
const SkScalar r = SkIntToScalar(20);
SkScalar rad = -SK_ScalarPI / 2;
const SkScalar drad = (n >> 1) * SK_ScalarPI * 2 / n;
SkPathBuilder builder;
builder.moveTo(c, c - r);
for (int i = 1; i < n; i++) {
rad += drad;
builder.lineTo(c + SkScalarCos(rad) * r, c + SkScalarSin(rad) * r);
}
builder.close();
return {builder.detach(), r * 2 * 6 / 5};
}
static PathDY make_star_5() { return make_star(5); }
static PathDY make_star_13() { return make_star(13); }
// We don't expect any output from this path.
static PathDY make_line() {
return {
SkPathBuilder().moveTo(30, 30)
.lineTo(120, 40)
.close()
.moveTo(150, 30)
.lineTo(150, 30)
.lineTo(300, 40)
.close()
.detach(),
40
};
}
static SkPath make_info() {
SkPathBuilder path;
path.moveTo(24, 4);
path.cubicTo(12.94999980926514f, 4,
4, 12.94999980926514f,
4, 24);
path.cubicTo(4, 35.04999923706055f,
12.94999980926514f, 44,
24, 44);
path.cubicTo(35.04999923706055f, 44,
44, 35.04999923706055f,
44, 24);
path.cubicTo(44, 12.95000076293945f,
35.04999923706055f, 4,
24, 4);
path.close();
path.moveTo(26, 34);
path.lineTo(22, 34);
path.lineTo(22, 22);
path.lineTo(26, 22);
path.lineTo(26, 34);
path.close();
path.moveTo(26, 18);
path.lineTo(22, 18);
path.lineTo(22, 14);
path.lineTo(26, 14);
path.lineTo(26, 18);
path.close();
return path.detach();
}
static SkPath make_accessibility() {
SkPathBuilder path;
path.moveTo(12, 2);
path.cubicTo(13.10000038146973f, 2,
14, 2.900000095367432f,
14, 4);
path.cubicTo(14, 5.099999904632568f,
13.10000038146973f, 6,
12, 6);
path.cubicTo(10.89999961853027f, 6,
10, 5.099999904632568f,
10, 4);
path.cubicTo(10, 2.900000095367432f,
10.89999961853027f, 2,
12, 2);
path.close();
path.moveTo(21, 9);
path.lineTo(15, 9);
path.lineTo(15, 22);
path.lineTo(13, 22);
path.lineTo(13, 16);
path.lineTo(11, 16);
path.lineTo(11, 22);
path.lineTo(9, 22);
path.lineTo(9, 9);
path.lineTo(3, 9);
path.lineTo(3, 7);
path.lineTo(21, 7);
path.lineTo(21, 9);
path.close();
return path.detach();
}
// test case for http://crbug.com/695196
static SkPath make_visualizer() {
SkPathBuilder path;
path.moveTo(1.9520f, 2.0000f);
path.conicTo(1.5573f, 1.9992f, 1.2782f, 2.2782f, 0.9235f);
path.conicTo(0.9992f, 2.5573f, 1.0000f, 2.9520f, 0.9235f);
path.lineTo(1.0000f, 5.4300f);
path.lineTo(17.0000f, 5.4300f);
path.lineTo(17.0000f, 2.9520f);
path.conicTo(17.0008f, 2.5573f, 16.7218f, 2.2782f, 0.9235f);
path.conicTo(16.4427f, 1.9992f, 16.0480f, 2.0000f, 0.9235f);
path.lineTo(1.9520f, 2.0000f);
path.close();
path.moveTo(2.7140f, 3.1430f);
path.conicTo(3.0547f, 3.1287f, 3.2292f, 3.4216f, 0.8590f);
path.conicTo(3.4038f, 3.7145f, 3.2292f, 4.0074f, 0.8590f);
path.conicTo(3.0547f, 4.3003f, 2.7140f, 4.2860f, 0.8590f);
path.conicTo(2.1659f, 4.2631f, 2.1659f, 3.7145f, 0.7217f);
path.conicTo(2.1659f, 3.1659f, 2.7140f, 3.1430f, 0.7217f);
path.lineTo(2.7140f, 3.1430f);
path.close();
path.moveTo(5.0000f, 3.1430f);
path.conicTo(5.3407f, 3.1287f, 5.5152f, 3.4216f, 0.8590f);
path.conicTo(5.6898f, 3.7145f, 5.5152f, 4.0074f, 0.8590f);
path.conicTo(5.3407f, 4.3003f, 5.0000f, 4.2860f, 0.8590f);
path.conicTo(4.4519f, 4.2631f, 4.4519f, 3.7145f, 0.7217f);
path.conicTo(4.4519f, 3.1659f, 5.0000f, 3.1430f, 0.7217f);
path.lineTo(5.0000f, 3.1430f);
path.close();
path.moveTo(7.2860f, 3.1430f);
path.conicTo(7.6267f, 3.1287f, 7.8012f, 3.4216f, 0.8590f);
path.conicTo(7.9758f, 3.7145f, 7.8012f, 4.0074f, 0.8590f);
path.conicTo(7.6267f, 4.3003f, 7.2860f, 4.2860f, 0.8590f);
path.conicTo(6.7379f, 4.2631f, 6.7379f, 3.7145f, 0.7217f);
path.conicTo(6.7379f, 3.1659f, 7.2860f, 3.1430f, 0.7217f);
path.close();
path.moveTo(1.0000f, 6.1900f);
path.lineTo(1.0000f, 14.3810f);
path.conicTo(0.9992f, 14.7757f, 1.2782f, 15.0548f, 0.9235f);
path.conicTo(1.5573f, 15.3338f, 1.9520f, 15.3330f, 0.9235f);
path.lineTo(16.0480f, 15.3330f);
path.conicTo(16.4427f, 15.3338f, 16.7218f, 15.0548f, 0.9235f);
path.conicTo(17.0008f, 14.7757f, 17.0000f, 14.3810f, 0.9235f);
path.lineTo(17.0000f, 6.1910f);
path.lineTo(1.0000f, 6.1910f);
path.lineTo(1.0000f, 6.1900f);
path.close();
return path.detach();
}
constexpr MakePathProc gProcs[] = {
make_frame,
make_triangle,
make_rect,
make_oval,
make_sawtooth_32,
make_star_5,
make_star_13,
make_line,
make_house,
make_sawtooth_3,
};
#define N SK_ARRAY_COUNT(gProcs)
class PathFillGM : public skiagm::GM {
SkPath fPath[N];
SkScalar fDY[N];
SkPath fInfoPath;
SkPath fAccessibilityPath;
SkPath fVisualizerPath;
protected:
void onOnceBeforeDraw() override {
for (size_t i = 0; i < N; i++) {
auto [path, dy] = gProcs[i]();
fPath[i] = path;
fDY[i] = dy;
}
fInfoPath = make_info();
fAccessibilityPath = make_accessibility();
fVisualizerPath = make_visualizer();
}
SkString onShortName() override {
return SkString("pathfill");
}
SkISize onISize() override {
return SkISize::Make(640, 480);
}
void onDraw(SkCanvas* canvas) override {
SkPaint paint;
paint.setAntiAlias(true);
for (size_t i = 0; i < N; i++) {
canvas->drawPath(fPath[i], paint);
canvas->translate(SkIntToScalar(0), fDY[i]);
}
canvas->save();
canvas->scale(0.300000011920929f, 0.300000011920929f);
canvas->translate(50, 50);
canvas->drawPath(fInfoPath, paint);
canvas->restore();
canvas->scale(2, 2);
canvas->translate(5, 15);
canvas->drawPath(fAccessibilityPath, paint);
canvas->scale(0.5f, 0.5f);
canvas->translate(5, 50);
canvas->drawPath(fVisualizerPath, paint);
}
private:
using INHERITED = skiagm::GM;
};
// test inverse-fill w/ a clip that completely excludes the geometry
class PathInverseFillGM : public skiagm::GM {
SkPath fPath[N];
SkScalar fDY[N];
protected:
void onOnceBeforeDraw() override {
for (size_t i = 0; i < N; i++) {
auto [path, dy] = gProcs[i]();
fPath[i] = path;
fDY[i] = dy;
}
}
SkString onShortName() override {
return SkString("pathinvfill");
}
SkISize onISize() override {
return SkISize::Make(450, 220);
}
static void show(SkCanvas* canvas, const SkPath& path, const SkPaint& paint,
const SkRect* clip, SkScalar top, const SkScalar bottom) {
canvas->save();
if (clip) {
SkRect r = *clip;
r.fTop = top;
r.fBottom = bottom;
canvas->clipRect(r);
}
canvas->drawPath(path, paint);
canvas->restore();
}
void onDraw(SkCanvas* canvas) override {
SkPath path = SkPathBuilder().addCircle(50, 50, 40)
.toggleInverseFillType()
.detach();
SkRect clipR = {0, 0, 100, 200};
canvas->translate(10, 10);
for (int doclip = 0; doclip <= 1; ++doclip) {
for (int aa = 0; aa <= 1; ++aa) {
SkPaint paint;
paint.setAntiAlias(SkToBool(aa));
canvas->save();
canvas->clipRect(clipR);
const SkRect* clipPtr = doclip ? &clipR : nullptr;
show(canvas, path, paint, clipPtr, clipR.fTop, clipR.centerY());
show(canvas, path, paint, clipPtr, clipR.centerY(), clipR.fBottom);
canvas->restore();
canvas->translate(SkIntToScalar(110), 0);
}
}
}
private:
using INHERITED = skiagm::GM;
};
DEF_SIMPLE_GM(rotatedcubicpath, canvas, 200, 200) {
SkPaint p;
p.setAntiAlias(true);
p.setStyle(SkPaint::kFill_Style);
canvas->translate(50, 50);
SkPath path;
path.moveTo(48,-23);
path.cubicTo(48,-29.5, 6,-30, 6,-30);
path.cubicTo(6,-30, 2,0, 2,0);
path.cubicTo(2,0, 44,-21.5, 48,-23);
path.close();
p.setColor(SK_ColorBLUE);
canvas->drawPath(path, p);
// Rotated path, which is not antialiased on GPU
p.setColor(SK_ColorRED);
canvas->rotate(90);
canvas->drawPath(path, p);
}
///////////////////////////////////////////////////////////////////////////////
DEF_GM( return new PathFillGM; )
DEF_GM( return new PathInverseFillGM; )
DEF_SIMPLE_GM(bug7792, canvas, 800, 800) {
// from skbug.com/7792 bug description
SkPaint p;
SkPath path;
path.moveTo(10, 10);
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
canvas->drawPath(path, p);
// from skbug.com/7792#c3
canvas->translate(200, 0);
path.reset();
path.moveTo(75, 50);
path.moveTo(100, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.lineTo(75, 50);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c9
canvas->translate(200, 0);
path.reset();
path.moveTo(10, 10);
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c11
canvas->translate(-200 * 2, 200);
path.reset();
path.moveTo(75, 150);
path.lineTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.moveTo(75, 150);
canvas->drawPath(path, p);
// from skbug.com/7792#c14
canvas->translate(200, 0);
path.reset();
path.moveTo(250, 75);
path.moveTo(250, 75);
path.moveTo(250, 75);
path.moveTo(100, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.lineTo(75, 75);
path.close();
path.lineTo(0, 0);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c15
canvas->translate(200, 0);
path.reset();
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.moveTo(250, 75);
canvas->drawPath(path, p);
// from skbug.com/7792#c17
canvas->translate(-200 * 2, 200);
path.reset();
path.moveTo(75, 10);
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.lineTo(75, 10);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c19
canvas->translate(200, 0);
path.reset();
path.moveTo(75, 75);
path.lineTo(75, 75);
path.lineTo(75, 75);
path.lineTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.close();
path.moveTo(10, 10);
path.lineTo(30, 10);
path.lineTo(10, 30);
canvas->drawPath(path, p);
// from skbug.com/7792#c23
canvas->translate(200, 0);
path.reset();
path.moveTo(75, 75);
path.lineTo(75, 75);
path.moveTo(75, 75);
path.lineTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c29
canvas->translate(-200 * 2, 200);
path.reset();
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.lineTo(75, 250);
path.moveTo(75, 75);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c31
canvas->translate(200, 0);
path.reset();
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.lineTo(75, 10);
path.moveTo(75, 75);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c36
canvas->translate(200, 0);
path.reset();
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(10, 150);
path.moveTo(75, 75);
path.lineTo(75, 75);
canvas->drawPath(path, p);
// from skbug.com/7792#c39
canvas->translate(200, -200 * 3);
path.reset();
path.moveTo(150, 75);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.lineTo(75, 100);
canvas->drawPath(path, p);
// from zero_length_paths_aa
canvas->translate(0, 200);
path.reset();
path.moveTo(150, 100);
path.lineTo(150, 100);
path.lineTo(150, 150);
path.lineTo(75, 150);
path.lineTo(75, 100);
path.lineTo(75, 75);
path.lineTo(150, 75);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c41
canvas->translate(0, 200);
path.reset();
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(140, 150);
path.lineTo(140, 75);
path.moveTo(75, 75);
path.close();
canvas->drawPath(path, p);
// from skbug.com/7792#c53
canvas->translate(0, 200);
path.reset();
path.moveTo(75, 75);
path.lineTo(150, 75);
path.lineTo(150, 150);
path.lineTo(140, 150);
path.lineTo(140, 75);
path.moveTo(75, 75);
path.close();
canvas->drawPath(path, p);
}
#include "include/core/SkSurface.h"
DEF_SIMPLE_GM(path_stroke_clip_crbug1070835, canvas, 25, 50) {
SkCanvas* orig = canvas;
auto surf = SkSurface::MakeRasterN32Premul(25, 25);
canvas = surf->getCanvas();
SkPaint p;
p.setColor(SK_ColorRED);
p.setAntiAlias(true);
p.setStyle(SkPaint::kStroke_Style);
p.setStrokeWidth(2);
canvas->scale(4.16666651f/2, 4.16666651f/2);
SkPath path;
SkPoint pts[] = {
{11, 12},
{11, 18.0751324f},
{6.07513189f, 23},
{-4.80825292E-7f, 23},
{-6.07513332f, 23},
{-11, 18.0751324f},
{-11, 11.999999f},
{-10.999999f, 5.92486763f},
{-6.07513189f, 1},
{1.31173692E-7f, 1},
{6.07513141f, 1},
{10.9999981f, 5.92486572f},
{11, 11.9999971f},
};
path.moveTo(pts[0]).cubicTo(pts[1], pts[2], pts[3])
.cubicTo(pts[4], pts[5], pts[6])
.cubicTo(pts[7], pts[8], pts[9])
.cubicTo(pts[10],pts[11],pts[12]);
canvas->drawPath(path, p);
surf->draw(orig, 0, 0);
}
DEF_SIMPLE_GM(path_arcto_skbug_9077, canvas, 200, 200) {
SkPaint p;
p.setColor(SK_ColorRED);
p.setAntiAlias(true);
p.setStyle(SkPaint::kStroke_Style);
p.setStrokeWidth(2);
SkPathBuilder path;
SkPoint pts[] = { {20, 20}, {100, 20}, {100, 60}, {130, 150}, {180, 160} };
SkScalar radius = 60;
path.moveTo(pts[0]);
path.lineTo(pts[1]);
path.lineTo(pts[2]);
path.close();
path.arcTo(pts[3], pts[4], radius);
canvas->drawPath(path.detach(), p);
}
Fix vertex alpha when connector edges intersect inner edges In the new GM, the left and right portions of the path have a shared vertex. The two edges leaving that vertex vertically towards the bottom of the image are nearly parallel but the right edge has a steeper slope. This leads to two sources of self intersections. The outset vertices for the left and right sides intersect, which converts some of those edges into "connecting" edges and removes others (preventing double hitting of pixels). However, these outset but now "connecting" edges from the right side also overlap with the inset vertices of the left shape, requiring additional vertex splitting and connecting edge creation. The old alpha logic when one of the intersecting edges was a connecting edge was to use its interpolated alpha value. In this case, since the connecting edge originated from two outset vertices, its end point alphas were 0 and the split alpha became 0, even though the other intersecting edge was an interior edge. This CL flips the logic around and ensures that any split vertex that is on the interior edges remains fully opaque, any vertex that is fully on the exterior remains fully transparent, and anything else uses the max of the interpolated alphas (equivalent to the old logic when one edge was connecting and one was exterior, but is more accurate if somehow we get two connecting edges intersecting). Bug: skia:11859 Change-Id: I85d2d54a8833e3c9da2fdd1a4f3a0513119730b9 Reviewed-on: https://skia-review.googlesource.com/c/skia/+/400596 Reviewed-by: Chris Dalton <csmartdalton@google.com> Reviewed-by: Brian Osman <brianosman@google.com> Commit-Queue: Michael Ludwig <michaelludwig@google.com>
2021-04-23 19:47:14 +00:00
DEF_SIMPLE_GM(path_skbug_11859, canvas, 512, 512) {
SkPaint paint;
paint.setColor(SK_ColorRED);
paint.setAntiAlias(true);
SkPath path;
path.moveTo(258, -2);
path.lineTo(258, 258);
path.lineTo(237, 258);
path.lineTo(240, -2);
path.lineTo(258, -2);
path.moveTo(-2, -2);
path.lineTo(240, -2);
path.lineTo(238, 131);
path.lineTo(-2, 131);
path.lineTo(-2, -2);
canvas->scale(2, 2);
canvas->drawPath(path, paint);
}
Use Wang's formula for quadratic and cubic point counts - most of the small diffs are because I moved GrWangsFormula.h out of the tessellate/ directory and into the geometry/ directory since it's more general than HW tessellation. The previous implementation was based on the heuristic that the distance from the true curve to the line segment would be divided by 4 every time the curve was recursively subdivided. This was a reasonable approximation if the curve had balanced curvature on both sides of the split. However, in the case of the new GM's curve, the left half was already very linear and the right half had much higher curves. This lead to the approximation reporting fewer points than required. Theoretically, those few points that weren't utilized by the left half of the curve could have been made available to the right half, but the implementation of that would be tricky. Instead, it now uses Wang's formula to compute the number of points. Since recursive subdivision leads to linearly spaced samples assuming it can't stop early, this point count represents a valid upper bound on what's needed. It also then ensures both left and right halves of a curve have the point counts they might need w/o updating the generation implementations. However, since the recursive point generation exits once each section has reached the error tolerance, in scenarios where the prior approximation was reasonable, we'll end up using fewer points than reported by Wang's. Hopefully that means there is negligible performance regression since we won't be increasing vertex counts by that much (except where needed for correctness). Bug: skia:11886 Change-Id: Iba39dbe4de82011775524583efd461b10c9259fe Reviewed-on: https://skia-review.googlesource.com/c/skia/+/405197 Reviewed-by: Chris Dalton <csmartdalton@google.com> Reviewed-by: Brian Salomon <bsalomon@google.com> Commit-Queue: Michael Ludwig <michaelludwig@google.com>
2021-05-11 14:00:12 +00:00
DEF_SIMPLE_GM(path_skbug_11886, canvas, 256, 256) {
SkPoint m = {0.f, 770.f};
SkPath path;
path.moveTo(m);
path.cubicTo(m + SkPoint{0.f, 1.f}, m + SkPoint{20.f, -750.f}, m + SkPoint{83.f, -746.f});
SkPaint paint;
paint.setAntiAlias(true);
canvas->drawPath(path, paint);
}