/*
* 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 "sk_tool_utils.h"
#include "SkBlendModePriv.h"
#include "SkPath.h"
#include "SkShader.h"
enum {
kXfermodeCount = (int)SkBlendMode::kLastMode + 1 + 1, // extra for arith
kShapeSize = 22,
kShapeSpacing = 36,
kShapeTypeSpacing = 4 * kShapeSpacing / 3,
kPaintSpacing = 4 * kShapeTypeSpacing,
kLabelSpacing = 3 * kShapeSize,
kMargin = kShapeSpacing / 2,
kXfermodeTypeSpacing = kLabelSpacing + 2 * kPaintSpacing + kShapeTypeSpacing,
kTitleSpacing = 3 * kShapeSpacing / 4,
kSubtitleSpacing = 5 * kShapeSpacing / 8
};
constexpr SkColor kBGColor = 0xc8d2b887;
constexpr SkColor kShapeColors[2] = {
0x82ff0080, // input color unknown
0xff00ffff, // input color opaque
};
enum Shape {
kSquare_Shape,
kDiamond_Shape,
kOval_Shape,
kConcave_Shape,
kLast_Shape = kConcave_Shape
};
/**
* Verifies AA works properly on all Xfermodes, including arithmetic, with both opaque and unknown
* src colors.
*/
class AAXfermodesGM : public skiagm::GM {
public:
AAXfermodesGM() {}
protected:
enum DrawingPass {
kCheckerboard_Pass,
kBackground_Pass,
kShape_Pass
};
SkString onShortName() override {
return SkString("aaxfermodes");
}
SkISize onISize() override {
return SkISize::Make(2 * kMargin + 2 * kXfermodeTypeSpacing -
(kXfermodeTypeSpacing - (kLabelSpacing + 2 * kPaintSpacing)),
2 * kMargin + kTitleSpacing + kSubtitleSpacing +
(1 + (int)SkBlendMode::kLastCoeffMode) * kShapeSpacing);
}
void onOnceBeforeDraw() override {
fLabelPaint.setAntiAlias(true);
sk_tool_utils::set_portable_typeface(&fLabelPaint);
fLabelPaint.setTextSize(5 * kShapeSize/8);
fLabelPaint.setSubpixelText(true);
constexpr SkScalar radius = -1.4f * kShapeSize/2;
SkPoint pts[4] = {
{-radius, 0},
{0, -1.33f * radius},
{radius, 0},
{0, 1.33f * radius}
};
fOval.moveTo(pts[0]);
fOval.quadTo(pts[1], pts[2]);
fOval.quadTo(pts[3], pts[0]);
fConcave.moveTo(-radius, 0);
fConcave.quadTo(0, 0, 0, -radius);
fConcave.quadTo(0, 0, radius, 0);
fConcave.quadTo(0, 0, 0, radius);
fConcave.quadTo(0, 0, -radius, 0);
fConcave.close();
}
void draw_pass(SkCanvas* canvas, DrawingPass drawingPass) {
SkRect clipRect =
{ -kShapeSize*11/16, -kShapeSize*11/16, kShapeSize*11/16, kShapeSize*11/16 };
canvas->save();
if (kCheckerboard_Pass == drawingPass) {
canvas->translate(kMargin, kMargin);
}
canvas->translate(0, kTitleSpacing);
for (size_t xfermodeSet = 0; xfermodeSet < 2; xfermodeSet++) {
size_t firstMode = ((size_t)SkBlendMode::kLastCoeffMode + 1) * xfermodeSet;
canvas->save();
if (kShape_Pass == drawingPass) {
fLabelPaint.setTextAlign(SkPaint::kCenter_Align);
canvas->drawText("Src Unknown", sizeof("Src Unknown") - 1,
kLabelSpacing + kShapeTypeSpacing * 1.5f + kShapeSpacing / 2,
kSubtitleSpacing / 2 + fLabelPaint.getTextSize() / 3, fLabelPaint);
canvas->drawText("Src Opaque", sizeof("Src Opaque") - 1,
kLabelSpacing + kShapeTypeSpacing * 1.5f + kShapeSpacing / 2 +
kPaintSpacing, kSubtitleSpacing / 2 + fLabelPaint.getTextSize() / 3,
fLabelPaint);
}
canvas->translate(0, kSubtitleSpacing + kShapeSpacing/2);
for (size_t m = 0; m <= (size_t)SkBlendMode::kLastCoeffMode; m++) {
if (firstMode + m > (size_t)SkBlendMode::kLastMode) {
break;
}
SkBlendMode mode = static_cast<SkBlendMode>(firstMode + m);
canvas->save();
if (kShape_Pass == drawingPass) {
this->drawModeName(canvas, mode);
}
canvas->translate(kLabelSpacing + kShapeSpacing/2, 0);
for (size_t colorIdx = 0; colorIdx < SK_ARRAY_COUNT(kShapeColors); colorIdx++) {
SkPaint paint;
this->setupShapePaint(canvas, kShapeColors[colorIdx], mode, &paint);
SkASSERT(colorIdx == 0 || 255 == paint.getAlpha());
canvas->save();
for (size_t shapeIdx = 0; shapeIdx <= kLast_Shape; shapeIdx++) {
if (kShape_Pass != drawingPass) {
canvas->save();
canvas->clipRect(clipRect);
if (kCheckerboard_Pass == drawingPass) {
sk_tool_utils::draw_checkerboard(canvas, 0xffffffff, 0xffc6c3c6,
10);
} else {
SkASSERT(kBackground_Pass == drawingPass);
canvas->drawColor(kBGColor, SkBlendMode::kSrc);
}
canvas->restore();
} else {
this->drawShape(canvas, static_cast<Shape>(shapeIdx), paint, mode);
}
canvas->translate(kShapeTypeSpacing, 0);
}
canvas->restore();
canvas->translate(kPaintSpacing, 0);
}
canvas->restore();
canvas->translate(0, kShapeSpacing);
}
canvas->restore();
canvas->translate(kXfermodeTypeSpacing, 0);
}
canvas->restore();
}
void onDraw(SkCanvas* canvas) override {
draw_pass(canvas, kCheckerboard_Pass);
canvas->saveLayer(nullptr, nullptr);
canvas->translate(kMargin, kMargin);
draw_pass(canvas, kBackground_Pass);
SkPaint titlePaint(fLabelPaint);
titlePaint.setTextSize(9 * titlePaint.getTextSize() / 8);
titlePaint.setFakeBoldText(true);
titlePaint.setTextAlign(SkPaint::kCenter_Align);
canvas->drawText("Porter Duff", sizeof("Porter Duff") - 1,
kLabelSpacing + 4 * kShapeTypeSpacing,
kTitleSpacing / 2 + titlePaint.getTextSize() / 3, titlePaint);
canvas->drawText("Advanced", sizeof("Advanced") - 1,
kXfermodeTypeSpacing + kLabelSpacing + 4 * kShapeTypeSpacing,
kTitleSpacing / 2 + titlePaint.getTextSize() / 3, titlePaint);
draw_pass(canvas, kShape_Pass);
canvas->restore();
}
void drawModeName(SkCanvas* canvas, SkBlendMode mode) {
const char* modeName = SkBlendMode_Name(mode);
fLabelPaint.setTextAlign(SkPaint::kRight_Align);
canvas->drawText(modeName, strlen(modeName), kLabelSpacing - kShapeSize / 4,
fLabelPaint.getTextSize() / 4, fLabelPaint);
}
void setupShapePaint(SkCanvas* canvas, GrColor color, SkBlendMode mode, SkPaint* paint) {
paint->setColor(color);
if (mode == SkBlendMode::kPlus) {
// Check for overflow, otherwise we might get confusing AA artifacts.
int maxSum = SkTMax(SkTMax(SkColorGetA(kBGColor) + SkColorGetA(color),
SkColorGetR(kBGColor) + SkColorGetR(color)),
SkTMax(SkColorGetG(kBGColor) + SkColorGetG(color),
SkColorGetB(kBGColor) + SkColorGetB(color)));
if (maxSum > 255) {
SkPaint dimPaint;
dimPaint.setAntiAlias(false);
dimPaint.setBlendMode(SkBlendMode::kDstIn);
if (255 != paint->getAlpha()) {
// Dim the src and dst colors.
dimPaint.setARGB(255 * 255 / maxSum, 0, 0, 0);
paint->setAlpha(255 * paint->getAlpha() / maxSum);
} else {
// Just clear the dst, we need to preserve the paint's opacity.
dimPaint.setARGB(0, 0, 0, 0);
}
canvas->drawRect({ -kShapeSpacing/2, -kShapeSpacing/2,
kShapeSpacing/2 + 3 * kShapeTypeSpacing, kShapeSpacing/2 },
dimPaint);
}
}
}
void drawShape(SkCanvas* canvas, Shape shape, const SkPaint& paint, SkBlendMode mode) {
SkASSERT(mode <= SkBlendMode::kLastMode);
SkPaint shapePaint(paint);
shapePaint.setAntiAlias(kSquare_Shape != shape);
shapePaint.setBlendMode(mode);
switch (shape) {
case kSquare_Shape:
canvas->drawRect({ -kShapeSize/2, -kShapeSize/2, kShapeSize/2, kShapeSize/2 },
shapePaint);
break;
case kDiamond_Shape:
canvas->save();
canvas->rotate(45);
canvas->drawRect({ -kShapeSize/2, -kShapeSize/2, kShapeSize/2, kShapeSize/2 },
shapePaint);
canvas->restore();
break;
case kOval_Shape:
canvas->save();
canvas->rotate(static_cast<SkScalar>((511 * (int)mode + 257) % 360));
canvas->drawPath(fOval, shapePaint);
canvas->restore();
break;
case kConcave_Shape:
canvas->drawPath(fConcave, shapePaint);
break;
default:
SkFAIL("Invalid shape.");
}
}
private:
SkPaint fLabelPaint;
SkPath fOval;
SkPath fConcave;
typedef skiagm::GM INHERITED;
};
DEF_GM( return new AAXfermodesGM; )