1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
/*
* 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/GrContext.h"
#include "src/gpu/GrContextPriv.h"
#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);
paint.setFilterQuality(kMedium_SkFilterQuality);
canvas->save();
#if SK_SUPPORT_GPU
GrContext* grContext = canvas->getGrContext();
if (grContext) {
sk_sp<SkImage> image = grContext->priv().testingOnly_getFontAtlasImage(
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++) {
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(); )
|
