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/*
* 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 "SampleCode.h"
#include "SkAnimTimer.h"
#include "SkView.h"
#include "SkCanvas.h"
#include "SkDrawable.h"
#include "SkPath.h"
#include "SkRandom.h"
#include "SkRSXform.h"
#include "SkSurface.h"
static SkImage* make_atlas(int atlasSize, int cellSize) {
SkImageInfo info = SkImageInfo::MakeN32Premul(atlasSize, atlasSize);
SkAutoTUnref<SkSurface> surface(SkSurface::NewRaster(info));
SkCanvas* canvas = surface->getCanvas();
SkPaint paint;
paint.setAntiAlias(true);
SkRandom rand;
const SkScalar half = cellSize * SK_ScalarHalf;
const char* s = "01234567890!@#$%^&*=+<>?abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
paint.setTextSize(28);
paint.setTextAlign(SkPaint::kCenter_Align);
int i = 0;
for (int y = 0; y < atlasSize; y += cellSize) {
for (int x = 0; x < atlasSize; x += cellSize) {
paint.setColor(rand.nextU());
paint.setAlpha(0xFF);
int index = i % strlen(s);
canvas->drawText(&s[index], 1, x + half, y + half + half/2, paint);
i += 1;
}
}
return surface->newImageSnapshot();
}
class DrawAtlasDrawable : public SkDrawable {
enum {
kMaxScale = 2,
kCellSize = 32,
kAtlasSize = 512,
};
struct Rec {
SkPoint fCenter;
SkVector fVelocity;
SkScalar fScale;
SkScalar fDScale;
SkScalar fRadian;
SkScalar fDRadian;
SkScalar fAlpha;
SkScalar fDAlpha;
void advance(const SkRect& bounds) {
fCenter += fVelocity;
if (fCenter.fX > bounds.right()) {
SkASSERT(fVelocity.fX > 0);
fVelocity.fX = -fVelocity.fX;
} else if (fCenter.fX < bounds.left()) {
SkASSERT(fVelocity.fX < 0);
fVelocity.fX = -fVelocity.fX;
}
if (fCenter.fY > bounds.bottom()) {
if (fVelocity.fY > 0) {
fVelocity.fY = -fVelocity.fY;
}
} else if (fCenter.fY < bounds.top()) {
if (fVelocity.fY < 0) {
fVelocity.fY = -fVelocity.fY;
}
}
fScale += fDScale;
if (fScale > 2 || fScale < SK_Scalar1/2) {
fDScale = -fDScale;
}
fRadian += fDRadian;
fRadian = SkScalarMod(fRadian, 2 * SK_ScalarPI);
fAlpha += fDAlpha;
if (fAlpha > 1) {
fAlpha = 1;
fDAlpha = -fDAlpha;
} else if (fAlpha < 0) {
fAlpha = 0;
fDAlpha = -fDAlpha;
}
}
SkRSXform asRSXform() const {
SkMatrix m;
m.setTranslate(-8, -8);
m.postScale(fScale, fScale);
m.postRotate(SkRadiansToDegrees(fRadian));
m.postTranslate(fCenter.fX, fCenter.fY);
SkRSXform x;
x.fSCos = m.getScaleX();
x.fSSin = m.getSkewY();
x.fTx = m.getTranslateX();
x.fTy = m.getTranslateY();
return x;
}
};
enum {
N = 256,
};
SkAutoTUnref<SkImage> fAtlas;
Rec fRec[N];
SkRect fTex[N];
SkRect fBounds;
bool fUseColors;
public:
DrawAtlasDrawable(const SkRect& r) : fBounds(r), fUseColors(false) {
SkRandom rand;
fAtlas.reset(make_atlas(kAtlasSize, kCellSize));
const SkScalar kMaxSpeed = 5;
const SkScalar cell = SkIntToScalar(kCellSize);
int i = 0;
for (int y = 0; y < kAtlasSize; y += kCellSize) {
for (int x = 0; x < kAtlasSize; x += kCellSize) {
const SkScalar sx = SkIntToScalar(x);
const SkScalar sy = SkIntToScalar(y);
fTex[i].setXYWH(sx, sy, cell, cell);
fRec[i].fCenter.set(sx + cell/2, sy + 3*cell/4);
fRec[i].fVelocity.fX = rand.nextSScalar1() * kMaxSpeed;
fRec[i].fVelocity.fY = rand.nextSScalar1() * kMaxSpeed;
fRec[i].fScale = 1;
fRec[i].fDScale = rand.nextSScalar1() / 4;
fRec[i].fRadian = 0;
fRec[i].fDRadian = rand.nextSScalar1() / 8;
fRec[i].fAlpha = rand.nextUScalar1();
fRec[i].fDAlpha = rand.nextSScalar1() / 10;
i += 1;
}
}
}
void toggleUseColors() {
fUseColors = !fUseColors;
}
protected:
void onDraw(SkCanvas* canvas) override {
SkRSXform xform[N];
SkColor colors[N];
for (int i = 0; i < N; ++i) {
fRec[i].advance(fBounds);
xform[i] = fRec[i].asRSXform();
if (fUseColors) {
colors[i] = SkColorSetARGB((int)(fRec[i].fAlpha * 0xFF), 0xFF, 0xFF, 0xFF);
}
}
SkPaint paint;
paint.setFilterQuality(kLow_SkFilterQuality);
const SkRect cull = this->getBounds();
const SkColor* colorsPtr = fUseColors ? colors : NULL;
canvas->drawAtlas(fAtlas, xform, fTex, colorsPtr, N, SkXfermode::kModulate_Mode,
&cull, &paint);
}
SkRect onGetBounds() override {
const SkScalar border = kMaxScale * kCellSize;
SkRect r = fBounds;
r.outset(border, border);
return r;
}
private:
typedef SkDrawable INHERITED;
};
class DrawAtlasView : public SampleView {
DrawAtlasDrawable* fDrawable;
public:
DrawAtlasView() {
fDrawable = new DrawAtlasDrawable(SkRect::MakeWH(640, 480));
}
~DrawAtlasView() override {
fDrawable->unref();
}
protected:
bool onQuery(SkEvent* evt) override {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "DrawAtlas");
return true;
}
SkUnichar uni;
if (SampleCode::CharQ(*evt, &uni)) {
switch (uni) {
case 'C': fDrawable->toggleUseColors(); this->inval(NULL); return true;
default: break;
}
}
return this->INHERITED::onQuery(evt);
}
void onDrawContent(SkCanvas* canvas) override {
canvas->drawDrawable(fDrawable);
this->inval(NULL);
}
#if 0
// TODO: switch over to use this for our animation
bool onAnimate(const SkAnimTimer& timer) override {
SkScalar angle = SkDoubleToScalar(fmod(timer.secs() * 360 / 24, 360));
fAnimatingDrawable->setSweep(angle);
return true;
}
#endif
private:
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new DrawAtlasView; }
static SkViewRegister reg(MyFactory);
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