Add text animation sample; tweak DrawShip sample
Committed: https://skia.googlesource.com/skia/+/3b484a40b3be7f0262afadeaf6b741ba5cedcfe1
Review URL: https://codereview.chromium.org/1410663005
diff --git a/samplecode/SampleAnimatedText.cpp b/samplecode/SampleAnimatedText.cpp
new file mode 100755
index 0000000..415cc9f
--- /dev/null
+++ b/samplecode/SampleAnimatedText.cpp
@@ -0,0 +1,164 @@
+/*
+ * 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"
+#if SK_SUPPORT_GPU
+#include "SkGpuDevice.h"
+#endif
+#include "SkRandom.h"
+#include "SkSystemEventTypes.h"
+#include "SkTime.h"
+#include "SkTypeface.h"
+#include "SkXfermode.h"
+#include "Timer.h"
+
+#include "GrContext.h"
+
+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;
+ SkSafeUnref(paint.setTypeface(SkTypeface::CreateFromFile("/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
+ SkBaseDevice* device = canvas->getDevice_just_for_deprecated_compatibility_testing();
+ GrContext* grContext = canvas->getGrContext();
+ if (grContext) {
+ grContext->drawFontCache(SkRect::MakeXYWH(512, 10, 512, 512), kA8_GrMaskFormat, paint,
+ reinterpret_cast<SkGpuDevice*>(device)->accessRenderTarget());
+ }
+#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->drawText(outString.c_str(), outString.size(), 512.f, 540.f, paint);
+ canvas->drawText(modeString.c_str(), modeString.size(), 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);
