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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"
#include "SkResourceCache.h"
#include "SkShadowUtils.h"
void draw_shadow(SkCanvas* canvas, const SkPath& path, int height, SkColor color, SkPoint3 lightPos,
SkScalar lightR, bool isAmbient, uint32_t flags) {
SkScalar ambientAlpha = isAmbient ? .5f : 0.f;
SkScalar spotAlpha = isAmbient ? 0.f : .5f;
SkShadowUtils::DrawShadow(canvas, path, height, lightPos, lightR, ambientAlpha, spotAlpha,
color, flags);
}
static constexpr int kW = 800;
static constexpr int kH = 800;
enum ShadowMode {
kDebugColorNoOccluders,
kDebugColorOccluders,
kGrayscale
};
void draw_paths(SkCanvas* canvas, ShadowMode mode) {
SkTArray<SkPath> paths;
paths.push_back().addRoundRect(SkRect::MakeWH(50, 50), 10, 10);
SkRRect oddRRect;
oddRRect.setNinePatch(SkRect::MakeWH(50, 50), 9, 13, 6, 16);
paths.push_back().addRRect(oddRRect);
paths.push_back().addRect(SkRect::MakeWH(50, 50));
paths.push_back().addCircle(25, 25, 25);
paths.push_back().cubicTo(100, 50, 20, 100, 0, 0);
paths.push_back().addOval(SkRect::MakeWH(20, 60));
static constexpr SkScalar kPad = 15.f;
static constexpr SkScalar kLightR = 100.f;
static constexpr SkScalar kHeight = 50.f;
// transform light position relative to canvas to handle tiling
SkPoint lightXY = canvas->getTotalMatrix().mapXY(250, 400);
SkPoint3 lightPos = { lightXY.fX, lightXY.fY, 500 };
canvas->translate(3 * kPad, 3 * kPad);
canvas->save();
SkScalar x = 0;
SkScalar dy = 0;
SkTDArray<SkMatrix> matrices;
matrices.push()->reset();
SkMatrix* m = matrices.push();
m->setRotate(33.f, 25.f, 25.f);
m->postScale(1.2f, 0.8f, 25.f, 25.f);
for (auto& m : matrices) {
for (int flags : { kNone_ShadowFlag, kTransparentOccluder_ShadowFlag }) {
for (const auto& path : paths) {
SkRect postMBounds = path.getBounds();
m.mapRect(&postMBounds);
SkScalar w = postMBounds.width() + kHeight;
SkScalar dx = w + kPad;
if (x + dx > kW - 3 * kPad) {
canvas->restore();
canvas->translate(0, dy);
canvas->save();
x = 0;
dy = 0;
}
canvas->save();
canvas->concat(m);
if (kDebugColorNoOccluders == mode || kDebugColorOccluders == mode) {
flags |= SkShadowFlags::kDisableTonalColor_ShadowFlag;
draw_shadow(canvas, path, kHeight, SK_ColorRED, lightPos, kLightR,
true, flags);
draw_shadow(canvas, path, kHeight, SK_ColorBLUE, lightPos, kLightR,
false, flags);
} else if (kGrayscale == mode) {
SkShadowUtils::DrawShadow(canvas, path, kHeight, lightPos, kLightR,
0.1f, 0.25f, SK_ColorBLACK, flags);
}
SkPaint paint;
paint.setAntiAlias(true);
if (kDebugColorNoOccluders == mode) {
// Draw the path outline in green on top of the ambient and spot shadows.
if (SkToBool(flags & kTransparentOccluder_ShadowFlag)) {
paint.setColor(SK_ColorCYAN);
} else {
paint.setColor(SK_ColorGREEN);
}
paint.setStyle(SkPaint::kStroke_Style);
paint.setStrokeWidth(0);
} else {
paint.setColor(kDebugColorOccluders == mode ? SK_ColorLTGRAY : SK_ColorWHITE);
if (SkToBool(flags & kTransparentOccluder_ShadowFlag)) {
paint.setAlpha(128);
}
paint.setStyle(SkPaint::kFill_Style);
}
canvas->drawPath(path, paint);
canvas->restore();
canvas->translate(dx, 0);
x += dx;
dy = SkTMax(dy, postMBounds.height() + kPad + kHeight);
}
}
}
// Show where the light is in x,y as a circle (specified in device space).
SkMatrix invCanvasM = canvas->getTotalMatrix();
if (invCanvasM.invert(&invCanvasM)) {
canvas->save();
canvas->concat(invCanvasM);
SkPaint paint;
paint.setColor(SK_ColorBLACK);
paint.setAntiAlias(true);
canvas->drawCircle(lightPos.fX, lightPos.fY, kLightR / 10.f, paint);
canvas->restore();
}
}
DEF_SIMPLE_GM(shadow_utils, canvas, kW, kH) {
draw_paths(canvas, kDebugColorNoOccluders);
}
DEF_SIMPLE_GM(shadow_utils_occl, canvas, kW, kH) {
draw_paths(canvas, kDebugColorOccluders);
}
DEF_SIMPLE_GM(shadow_utils_gray, canvas, kW, kH) {
draw_paths(canvas, kGrayscale);
}
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