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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 "SkView.h"
#include "SkCanvas.h"
#include "SkUtils.h"
#include "SkColorPriv.h"
#include "SkColorFilter.h"
#include "SkImage.h"
#include "SkRandom.h"
#include "SkTime.h"
#include "SkTypeface.h"
#include "Timer.h"
#if SK_SUPPORT_GPU
#include "GrContext.h"
#include "GrContextPriv.h"
#endif
SkRandom gRand;
static void DrawTheText(SkCanvas* canvas, const char text[], size_t length, SkScalar x, SkScalar y,
const SkPaint& paint) {
SkPaint p(paint);
p.setSubpixelText(true);
canvas->drawText(text, length, x, y, p);
}
// This sample demonstrates the cache behavior of bitmap vs. distance field text
// It renders variously sized text with an animated scale and rotation.
// Specifically one should:
// use 'D' to toggle between bitmap and distance field fonts
// use '2' to toggle between scaling the image by 2x
// -- this feature boosts the rendering out of the small point-size
// SDF-text special case (which falls back to bitmap fonts for small points)
class AnimatedTextView : public SampleView {
public:
AnimatedTextView() : fScale(1.0f), fScaleInc(0.1f), fRotation(0.0f), fSizeScale(1) {
fCurrentTime = 0;
fTimer.start();
memset(fTimes, 0, sizeof(fTimes));
}
protected:
// overrides from SkEventSink
bool onQuery(SkEvent* evt) override {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "AnimatedText");
return true;
}
SkUnichar uni;
if (SampleCode::CharQ(*evt, &uni)) {
if ('2' == uni) {
if (fSizeScale == 2) {
fSizeScale = 1;
} else {
fSizeScale = 2;
}
return true;
}
}
return this->INHERITED::onQuery(evt);
}
void onDrawContent(SkCanvas* canvas) override {
SkPaint paint;
paint.setTypeface(SkTypeface::MakeFromFile("/skimages/samplefont.ttf"));
paint.setAntiAlias(true);
paint.setFilterQuality(kMedium_SkFilterQuality);
SkString outString("fps: ");
fTimer.end();
// TODO: generalize this timing code in utils
fTimes[fCurrentTime] = (float)(fTimer.fWall);
fCurrentTime = (fCurrentTime + 1) & 0x1f;
float meanTime = 0.0f;
for (int i = 0; i < 32; ++i) {
meanTime += fTimes[i];
}
meanTime /= 32.f;
SkScalar fps = 1000.f / meanTime;
outString.appendScalar(fps);
outString.append(" ms: ");
outString.appendScalar(meanTime);
SkString modeString("Text scale: ");
modeString.appendU32(fSizeScale);
modeString.append("x");
fTimer.start();
canvas->save();
#if SK_SUPPORT_GPU
GrContext* grContext = canvas->getGrContext();
if (grContext) {
sk_sp<SkImage> image = grContext->contextPriv().getFontAtlasImage_ForTesting(
GrMaskFormat::kA8_GrMaskFormat);
canvas->drawImageRect(image,
SkRect::MakeXYWH(512.0f, 10.0f, 512.0f, 512.0f), &paint);
}
#endif
canvas->translate(180, 180);
canvas->rotate(fRotation);
canvas->scale(fScale, fScale);
canvas->translate(-180, -180);
const char* text = "Hamburgefons";
size_t length = strlen(text);
SkScalar y = SkIntToScalar(0);
for (int i = 12; i <= 26; i++) {
paint.setTextSize(SkIntToScalar(i*fSizeScale));
y += paint.getFontSpacing();
DrawTheText(canvas, text, length, SkIntToScalar(110), y, paint);
}
canvas->restore();
paint.setTextSize(16);
// canvas->drawString(outString, 512.f, 540.f, paint);
canvas->drawString(modeString, 768.f, 540.f, paint);
}
bool onAnimate(const SkAnimTimer& timer) override {
// We add noise to the scale and rotation animations to
// keep the font atlas from falling into a steady state
fRotation += (1.0f + gRand.nextRangeF(-0.1f, 0.1f));
fScale += (fScaleInc + gRand.nextRangeF(-0.025f, 0.025f));
if (fScale >= 2.0f) {
fScaleInc = -0.1f;
} else if (fScale <= 1.0f) {
fScaleInc = 0.1f;
}
return true;
}
private:
float fScale;
float fScaleInc;
float fRotation;
int fSizeScale;
WallTimer fTimer;
float fTimes[32];
int fCurrentTime;
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new AnimatedTextView; }
static SkViewRegister reg(MyFactory);
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