blob: 34f58f814e124710548aeec112846c900e912265 [file] [log] [blame]
/*
* Copyright 2018 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/SkMatrix.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPath.h"
#include "include/core/SkPoint.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"
#include "src/base/SkRandom.h"
#include "tools/ToolUtils.h"
#include <array>
#include <vector>
namespace skiagm {
static constexpr int kPadSize = 20;
static constexpr int kBoxSize = 100;
static constexpr SkPoint kJitters[] = {{0, 0}, {.5f, .5f}, {2/3.f, 1/3.f}};
// Tests various corners of different angles falling on the same pixel, particularly to ensure
// analytic AA is working properly.
class SharedCornersGM : public GM {
public:
SharedCornersGM() { this->setBGColor(ToolUtils::color_to_565(0xFF1A65D7)); }
protected:
SkString getName() const override { return SkString("sharedcorners"); }
SkISize getISize() override {
constexpr int numRows = 3 * 2;
constexpr int numCols = (1 + std::size(kJitters)) * 2;
return SkISize::Make(numCols * (kBoxSize + kPadSize) + kPadSize,
numRows * (kBoxSize + kPadSize) + kPadSize);
}
void onOnceBeforeDraw() override {
fFillPaint.setColor(SK_ColorWHITE);
fFillPaint.setAntiAlias(true);
fWireFramePaint = fFillPaint;
fWireFramePaint.setStyle(SkPaint::kStroke_Style);
}
void onDraw(SkCanvas* canvas) override {
canvas->translate(kPadSize, kPadSize);
canvas->save();
// Adjacent rects.
this->drawTriangleBoxes(canvas,
{{0, 0}, {40, 0}, {80, 0}, {120, 0},
{0, 20}, {40, 20}, {80, 20}, {120, 20},
{40, 40}, {80, 40},
{40, 60}, {80, 60}},
{{{0, 1, 4}}, {{1, 5, 4}},
{{5, 1, 6}}, {{1, 2, 6}},
{{2, 3, 6}}, {{3, 7, 6}},
{{8, 5, 9}}, {{5, 6, 9}},
{{10, 8, 11}}, {{8, 9, 11}}});
// Obtuse angles.
this->drawTriangleBoxes(canvas,
{{ 0, 0}, {10, 0}, {20, 0},
{ 0, 2}, {20, 2},
{10, 4},
{ 0, 6}, {20, 6},
{ 0, 8}, {10, 8}, {20, 8}},
{{{3, 1, 4}}, {{4, 5, 3}}, {{6, 5, 7}}, {{7, 9, 6}},
{{0, 1, 3}}, {{1, 2, 4}},
{{3, 5, 6}}, {{5, 4, 7}},
{{6, 9, 8}}, {{9, 7, 10}}});
canvas->restore();
canvas->translate((kBoxSize + kPadSize) * 4, 0);
// Right angles.
this->drawTriangleBoxes(canvas,
{{0, 0}, {-1, 0}, {0, -1}, {1, 0}, {0, 1}},
{{{0, 1, 2}}, {{0, 2, 3}}, {{0, 3, 4}}, {{0, 4, 1}}});
// Acute angles.
SkRandom rand;
std::vector<SkPoint> pts;
std::vector<std::array<int, 3>> indices;
SkScalar theta = 0;
pts.push_back({0, 0});
while (theta < 2*SK_ScalarPI) {
pts.push_back({SkScalarCos(theta), SkScalarSin(theta)});
if (pts.size() > 2) {
indices.push_back({{0, (int)pts.size() - 2, (int)pts.size() - 1}});
}
theta += rand.nextRangeF(0, SK_ScalarPI/3);
}
indices.push_back({{0, (int)pts.size() - 1, 1}});
this->drawTriangleBoxes(canvas, pts, indices);
}
void drawTriangleBoxes(SkCanvas* canvas, const std::vector<SkPoint>& points,
const std::vector<std::array<int, 3>>& triangles) {
SkPath path;
path.setFillType(SkPathFillType::kEvenOdd);
path.setIsVolatile(true);
for (const std::array<int, 3>& triangle : triangles) {
path.moveTo(points[triangle[0]]);
path.lineTo(points[triangle[1]]);
path.lineTo(points[triangle[2]]);
path.close();
}
SkScalar scale = kBoxSize / std::max(path.getBounds().height(), path.getBounds().width());
path.transform(SkMatrix::Scale(scale, scale));
this->drawRow(canvas, path);
canvas->translate(0, kBoxSize + kPadSize);
SkMatrix rot;
rot.setRotate(45, path.getBounds().centerX(), path.getBounds().centerY());
path.transform(rot);
this->drawRow(canvas, path);
canvas->translate(0, kBoxSize + kPadSize);
rot.setRotate(-45 - 69.38111f, path.getBounds().centerX(), path.getBounds().centerY());
path.transform(rot);
this->drawRow(canvas, path);
canvas->translate(0, kBoxSize + kPadSize);
}
void drawRow(SkCanvas* canvas, const SkPath& path) {
SkAutoCanvasRestore acr(canvas, true);
const SkRect& bounds = path.getBounds();
canvas->translate((kBoxSize - bounds.width()) / 2 - bounds.left(),
(kBoxSize - bounds.height()) / 2 - bounds.top());
canvas->drawPath(path, fWireFramePaint);
canvas->translate(kBoxSize + kPadSize, 0);
for (SkPoint jitter : kJitters) {
{
SkAutoCanvasRestore acr2(canvas, true);
canvas->translate(jitter.x(), jitter.y());
canvas->drawPath(path, fFillPaint);
}
canvas->translate(kBoxSize + kPadSize, 0);
}
}
SkPaint fWireFramePaint;
SkPaint fFillPaint;
};
DEF_GM(return new SharedCornersGM;)
} // namespace skiagm