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/*
* Copyright 2017 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 "SkCanvas.h"
#include "SkPath.h"
namespace {
// Test thin stroked rect (stroked "by hand", not by stroking).
void draw_thin_stroked_rect(SkCanvas* canvas, const SkPaint& paint, SkScalar width) {
SkPath path;
path.moveTo(10 + width, 10 + width);
path.lineTo(40, 10 + width);
path.lineTo(40, 20);
path.lineTo(10 + width, 20);
path.moveTo(10, 10);
path.lineTo(10, 20 + width);
path.lineTo(40 + width, 20 + width);
path.lineTo(40 + width, 10);
canvas->drawPath(path, paint);
}
void draw_thin_right_angle(SkCanvas* canvas, const SkPaint& paint, SkScalar width) {
SkPath path;
path.moveTo(10 + width, 10 + width);
path.lineTo(40, 10 + width);
path.lineTo(40, 20);
path.lineTo(40 + width, 20 + width);
path.lineTo(40 + width, 10);
path.lineTo(10, 10);
canvas->drawPath(path, paint);
}
// Test thin horizontal line (<1 pixel) which should give lower alpha.
void draw_golf_club(SkCanvas* canvas, const SkPaint& paint, SkScalar width) {
SkPath path;
path.moveTo(20, 10);
path.lineTo(80, 10);
path.lineTo(80, 10 + width);
path.lineTo(30, 10 + width);
path.lineTo(30, 20);
path.lineTo(20, 20);
canvas->drawPath(path, paint);
}
// Test thin lines between two filled regions. The outer edges overlap, but
// there are no inverted edges to fix.
void draw_barbell(SkCanvas* canvas, const SkPaint& paint, SkScalar width) {
SkScalar offset = width * 0.5f;
SkPath path;
path.moveTo(30, 5);
path.lineTo(40 - offset, 15 - offset);
path.lineTo(60 + offset, 15 - offset);
path.lineTo(70, 5);
path.lineTo(70, 25);
path.lineTo(60 + offset, 15 + offset);
path.lineTo(40 - offset, 15 + offset);
path.lineTo(30, 25);
canvas->drawPath(path, paint);
}
// Test a thin rectangle and triangle. The top and bottom inner edges of the
// rectangle and all inner edges of the triangle invert on stroking.
void draw_thin_rect_and_triangle(SkCanvas* canvas, const SkPaint& paint, SkScalar width) {
SkPath path;
path.moveTo(30, 5);
path.lineTo(30 + width, 5);
path.lineTo(30 + width, 25);
path.lineTo(30, 25);
path.moveTo(40, 5);
path.lineTo(40 + width, 5);
path.lineTo(40, 25);
canvas->drawPath(path, paint);
}
// Two triangles joined by a very thin bridge. The tiny triangle formed
// by the inner edges at the bridge is inverted.
// (These are actually now more phat pants than hipster pants.)
void draw_hipster_pants(SkCanvas* canvas, const SkPaint& paint, SkScalar width) {
SkPath path;
path.moveTo(10, 10);
path.lineTo(10, 20);
path.lineTo(50, 10 + width);
path.lineTo(90, 20);
path.lineTo(90, 10);
canvas->drawPath(path, paint);
}
// A thin z-shape whose interior inverts on stroking. The top and bottom inner edges invert, and
// the connector edges at the "elbows" intersect the inner edges.
void draw_skinny_snake(SkCanvas* canvas, const SkPaint& paint, SkScalar width) {
SkPath path;
path.moveTo(20 + width, 10);
path.lineTo(20 + width, 20);
path.lineTo(10 + width, 30);
path.lineTo(10 + width, 40);
path.lineTo(10 - width, 40);
path.lineTo(10 - width, 30);
path.lineTo(20 - width, 20);
path.lineTo(20 - width, 10);
canvas->drawPath(path, paint);
}
// Test pointy features whose outer edges extend far to the right on stroking.
void draw_pointy_golf_club(SkCanvas* canvas, const SkPaint& paint, SkScalar width) {
SkPath path;
path.moveTo(20, 10);
path.lineTo(80, 10 + width * 0.5);
path.lineTo(30, 10 + width);
path.lineTo(30, 20);
path.lineTo(20, 20);
canvas->drawPath(path, paint);
}
};
DEF_SIMPLE_GM(thinconcavepaths, canvas, 550, 400) {
SkPaint paint;
paint.setAntiAlias(true);
paint.setStyle(SkPaint::kFill_Style);
canvas->save();
for (SkScalar width = 0.5f; width < 2.05f; width += 0.25f) {
draw_thin_stroked_rect(canvas, paint, width);
canvas->translate(0, 25);
}
canvas->restore();
canvas->translate(50, 0);
canvas->save();
for (SkScalar width = 0.5f; width < 2.05f; width += 0.25f) {
draw_thin_right_angle(canvas, paint, width);
canvas->translate(0, 25);
}
canvas->restore();
canvas->translate(40, 0);
canvas->save();
for (SkScalar width = 0.2f; width < 2.1f; width += 0.2f) {
draw_golf_club(canvas, paint, width);
canvas->translate(0, 30);
}
canvas->restore();
canvas->translate(70, 0);
canvas->save();
for (SkScalar width = 0.2f; width < 2.1f; width += 0.2f) {
draw_thin_rect_and_triangle(canvas, paint, width);
canvas->translate(0, 30);
}
canvas->restore();
canvas->translate(30, 0);
canvas->save();
for (SkScalar width = 0.2f; width < 2.1f; width += 0.2f) {
draw_barbell(canvas, paint, width);
canvas->translate(0, 30);
}
canvas->restore();
canvas->translate(80, 0);
canvas->save();
for (SkScalar width = 0.2f; width < 2.1f; width += 0.2f) {
draw_hipster_pants(canvas, paint, width);
canvas->translate(0, 30);
}
canvas->restore();
canvas->translate(100, 0);
canvas->save();
for (SkScalar width = 0.2f; width < 2.1f; width += 0.2f) {
draw_skinny_snake(canvas, paint, width);
canvas->translate(0, 30);
}
canvas->restore();
canvas->translate(30, 0);
canvas->save();
for (SkScalar width = 0.2f; width < 2.1f; width += 0.2f) {
draw_pointy_golf_club(canvas, paint, width);
canvas->translate(0, 30);
}
canvas->restore();
canvas->translate(100, 0);
}
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