| /* |
| * 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 "include/core/SkCanvas.h" |
| #include "include/core/SkColorFilter.h" |
| #include "include/core/SkColorPriv.h" |
| #include "include/core/SkFont.h" |
| #include "include/core/SkImage.h" |
| #include "include/core/SkTime.h" |
| #include "include/core/SkTypeface.h" |
| #include "include/utils/SkRandom.h" |
| #include "samplecode/Sample.h" |
| #include "src/utils/SkUTF.h" |
| |
| #if SK_SUPPORT_GPU |
| #include "include/gpu/GrDirectContext.h" |
| #include "src/gpu/ganesh/GrDirectContextPriv.h" |
| |
| using MaskFormat = skgpu::MaskFormat; |
| #endif |
| |
| SkRandom gRand; |
| |
| static void DrawTheText(SkCanvas* canvas, const char text[], size_t length, SkScalar x, SkScalar y, |
| const SkFont& font, const SkPaint& paint) { |
| SkFont f(font); |
| f.setSubpixel(true); |
| canvas->drawSimpleText(text, length, SkTextEncoding::kUTF8, x, y, f, paint); |
| } |
| |
| // 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 Sample { |
| float fScale = 1; |
| float fScaleInc = 0.1f; |
| float fRotation = 0; |
| int fSizeScale = 1; |
| |
| SkString name() override { return SkString("AnimatedText"); } |
| |
| bool onChar(SkUnichar uni) override { |
| if ('2' == uni) { |
| if (fSizeScale == 2) { |
| fSizeScale = 1; |
| } else { |
| fSizeScale = 2; |
| } |
| return true; |
| } |
| return false; |
| } |
| |
| void onDrawContent(SkCanvas* canvas) override { |
| SkFont font(SkTypeface::MakeFromFile("/skimages/samplefont.ttf")); |
| |
| SkPaint paint; |
| paint.setAntiAlias(true); |
| |
| canvas->save(); |
| |
| #if SK_SUPPORT_GPU |
| auto direct = GrAsDirectContext(canvas->recordingContext()); |
| if (direct) { |
| SkSamplingOptions sampling(SkFilterMode::kLinear, SkMipmapMode::kNearest); |
| sk_sp<SkImage> image = direct->priv().testingOnly_getFontAtlasImage(MaskFormat::kA8); |
| const SkRect rect = SkRect::MakeXYWH(512.0f, 10.0f, 512.0f, 512.0f); |
| canvas->drawImageRect(image.get(), rect, rect, sampling, &paint, |
| SkCanvas::kFast_SrcRectConstraint); |
| } |
| #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++) { |
| font.setSize(SkIntToScalar(i*fSizeScale)); |
| y += font.getSpacing(); |
| DrawTheText(canvas, text, length, SkIntToScalar(110), y, font, paint); |
| } |
| canvas->restore(); |
| |
| font.setSize(16); |
| } |
| |
| bool onAnimate(double nanos) override { |
| // TODO: use nanos |
| // 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; |
| } |
| }; |
| |
| DEF_SAMPLE( return new AnimatedTextView(); ) |