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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 "SampleCode.h"
#include "Resources.h"
#include "SkCanvas.h"
#include "SkImage.h"
#include "SkPath.h"
#include "SkPoint3.h"
#include "SkShadowUtils.h"
////////////////////////////////////////////////////////////////////////////
// Sample to demonstrate tonal color shadows
class ShadowColorView : public SampleView {
SkPath fRectPath;
int fZIndex;
bool fShowAmbient;
bool fShowSpot;
bool fUseAlt;
bool fShowObject;
bool fTwoPassColor;
bool fDarkBackground;
public:
ShadowColorView()
: fZIndex(8)
, fShowAmbient(true)
, fShowSpot(true)
, fUseAlt(false)
, fShowObject(true)
, fTwoPassColor(false)
, fDarkBackground(false) {}
protected:
void onOnceBeforeDraw() override {
fRectPath.addRect(SkRect::MakeXYWH(-50, -50, 100, 100));
}
// overrides from SkEventSink
bool onQuery(SkEvent* evt) override {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "ShadowColor");
return true;
}
SkUnichar uni;
if (SampleCode::CharQ(*evt, &uni)) {
bool handled = false;
switch (uni) {
case 'W':
fShowAmbient = !fShowAmbient;
handled = true;
break;
case 'S':
fShowSpot = !fShowSpot;
handled = true;
break;
case 'T':
fUseAlt = !fUseAlt;
handled = true;
break;
case 'O':
fShowObject = !fShowObject;
handled = true;
break;
case 'X':
fTwoPassColor = !fTwoPassColor;
handled = true;
break;
case 'Z':
fDarkBackground = !fDarkBackground;
handled = true;
break;
case '>':
fZIndex = SkTMin(9, fZIndex+1);
handled = true;
break;
case '<':
fZIndex = SkTMax(0, fZIndex-1);
handled = true;
break;
default:
break;
}
if (handled) {
return true;
}
}
return this->INHERITED::onQuery(evt);
}
void drawShadowedPath(SkCanvas* canvas, const SkPath& path,
const SkPoint3& zPlaneParams,
const SkPaint& paint, SkScalar ambientAlpha,
const SkPoint3& lightPos, SkScalar lightWidth, SkScalar spotAlpha) {
if (!fShowAmbient) {
ambientAlpha = 0;
}
if (!fShowSpot) {
spotAlpha = 0;
}
uint32_t flags = 0;
if (fUseAlt) {
flags |= SkShadowFlags::kGeometricOnly_ShadowFlag;
}
if (fTwoPassColor) {
SkColor ambientColor = SkColorSetARGB(ambientAlpha*255, 0, 0, 0);
SkShadowUtils::DrawShadow(canvas, path, zPlaneParams,
lightPos, lightWidth,
ambientColor, SK_ColorTRANSPARENT, flags);
if (paint.getColor() != SK_ColorBLACK) {
SkColor color = paint.getColor();
uint8_t max = SkTMax(SkTMax(SkColorGetR(color), SkColorGetG(color)),
SkColorGetB(color));
uint8_t min = SkTMin(SkTMin(SkColorGetR(color), SkColorGetG(color)),
SkColorGetB(color));
SkScalar luminance = 0.5f*(max + min) / 255.f;
SkScalar alpha = (.6 - .4*luminance)*luminance*luminance + 0.3f;
spotAlpha -= (alpha - 0.3f)*.5f;
SkColor spotColor = SkColorSetARGB(alpha*SkColorGetA(color), SkColorGetR(color),
SkColorGetG(color), SkColorGetB(color));
SkShadowUtils::DrawShadow(canvas, path, zPlaneParams,
lightPos, lightWidth,
SK_ColorTRANSPARENT, spotColor, flags);
}
SkColor spotGreyscale = SkColorSetARGB(spotAlpha * 255, 0, 0, 0);
SkShadowUtils::DrawShadow(canvas, path, zPlaneParams,
lightPos, lightWidth,
SK_ColorTRANSPARENT, spotGreyscale, flags);
} else {
SkColor color = paint.getColor();
SkColor baseAmbient = SkColorSetARGB(ambientAlpha*SkColorGetA(color),
SkColorGetR(color), SkColorGetG(color),
SkColorGetB(color));
SkColor baseSpot = SkColorSetARGB(spotAlpha*SkColorGetA(color),
SkColorGetR(color), SkColorGetG(color),
SkColorGetB(color));
SkColor tonalAmbient, tonalSpot;
SkShadowUtils::ComputeTonalColors(baseAmbient, baseSpot, &tonalAmbient, &tonalSpot);
SkShadowUtils::DrawShadow(canvas, path, zPlaneParams,
lightPos, lightWidth,
tonalAmbient, tonalSpot, flags);
}
if (fShowObject) {
canvas->drawPath(path, paint);
} else {
SkPaint strokePaint;
strokePaint.setColor(paint.getColor());
strokePaint.setStyle(SkPaint::kStroke_Style);
canvas->drawPath(path, strokePaint);
}
}
void onDrawContent(SkCanvas* canvas) override {
const SkScalar kLightWidth = 600;
const SkScalar kAmbientAlpha = 0.03f;
const SkScalar kSpotAlpha = 0.25f;
const SkScalar kZValues[10] = { 1, 2, 3, 4, 6, 8, 9, 12, 16, 24 };
const SkColor kColors[30] = {
// purples
0xFF3A0072, 0xFF5D0099, 0xFF7F12B2, 0xFFA02AD1, 0xFFC245E5,
0xFFE95AF9, 0xFFFC79F0, 0xFFFDA6F0, 0xFFFFCCF8, 0xFFFFE1F9,
// oranges
0xFFEA3200, 0xFFFF4E00, 0xFFFF7300, 0xFFFF9100, 0xFFFFB000,
0xFFFFCE00, 0xFFFFE000, 0xFFFFF64D, 0xFFFFF98F, 0xFFFFFBCC,
// teals
0xFF004D51, 0xFF066266, 0xFF057F7F, 0xFF009999, 0xFF00B2B2,
0xFF15CCBE, 0xFF25E5CE, 0xFF2CFFE0, 0xFF80FFEA, 0xFFB3FFF0
};
SkPaint paint;
paint.setAntiAlias(true);
if (fDarkBackground) {
canvas->drawColor(0xFF111111);
paint.setColor(SK_ColorWHITE);
} else {
canvas->drawColor(0xFFEAEAEA);
paint.setColor(SK_ColorBLACK);
}
if (fTwoPassColor) {
canvas->drawText("Two pass", 8, 10, 15, paint);
} else {
canvas->drawText("One pass", 8, 10, 15, paint);
}
SkPoint3 lightPos = { 75, -400, 600 };
SkPoint3 zPlaneParams = SkPoint3::Make(0, 0, kZValues[fZIndex]);
SkScalar yPos = 75;
for (int row = 0; row < 3; ++row) {
lightPos.fX = 75;
SkScalar xPos = 75;
for (int col = 0; col < 10; ++col) {
paint.setColor(kColors[10*row + col]);
canvas->save();
canvas->translate(xPos, yPos);
this->drawShadowedPath(canvas, fRectPath, zPlaneParams, paint, kAmbientAlpha,
lightPos, kLightWidth, kSpotAlpha);
canvas->restore();
lightPos.fX += 120;
xPos += 120;
}
lightPos.fY += 200;
yPos += 200;
}
}
private:
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new ShadowColorView; }
static SkViewRegister reg(MyFactory);
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