xref: /aosp_15_r20/external/skia/gm/textblobtransforms.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2015 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #include "gm/gm.h"
9 #include "include/core/SkCanvas.h"
10 #include "include/core/SkColor.h"
11 #include "include/core/SkFont.h"
12 #include "include/core/SkFontTypes.h"
13 #include "include/core/SkPaint.h"
14 #include "include/core/SkRect.h"
15 #include "include/core/SkRefCnt.h"
16 #include "include/core/SkScalar.h"
17 #include "include/core/SkSize.h"
18 #include "include/core/SkString.h"
19 #include "include/core/SkTextBlob.h"
20 #include "include/core/SkTypeface.h"
21 #include "tools/ToolUtils.h"
22 #include "tools/fonts/FontToolUtils.h"
23 
24 #include <string.h>
25 
26 namespace skiagm {
27 class TextBlobTransforms : public GM {
28 public:
29     // This gm tests that textblobs can be translated, rotated, and scaled
TextBlobTransforms()30     TextBlobTransforms() {}
31 
32 protected:
onOnceBeforeDraw()33     void onOnceBeforeDraw() override {
34         SkTextBlobBuilder builder;
35 
36         // make textblob.  To stress distance fields, we choose sizes appropriately
37         SkFont font(ToolUtils::DefaultPortableTypeface(), 162);
38         font.setEdging(SkFont::Edging::kAlias);
39         const char* text = "A";
40 
41         SkRect bounds;
42         font.measureText(text, strlen(text), SkTextEncoding::kUTF8, &bounds);
43         ToolUtils::add_to_text_blob(&builder, text, font, 0, 0);
44 
45         // Medium
46         SkScalar xOffset = bounds.width() + 5;
47         font.setSize(72);
48         text = "B";
49         ToolUtils::add_to_text_blob(&builder, text, font, xOffset, 0);
50 
51         font.measureText(text, strlen(text), SkTextEncoding::kUTF8, &bounds);
52         SkScalar yOffset = bounds.height();
53 
54         // Small
55         font.setSize(32);
56         text = "C";
57         ToolUtils::add_to_text_blob(&builder, text, font, xOffset, -yOffset - 10);
58 
59         // build
60         fBlob = builder.make();
61     }
62 
getName() const63     SkString getName() const override { return SkString("textblobtransforms"); }
64 
getISize()65     SkISize getISize() override { return SkISize::Make(kWidth, kHeight); }
66 
onDraw(SkCanvas * canvas)67     void onDraw(SkCanvas* canvas) override {
68 
69         canvas->drawColor(SK_ColorGRAY);
70 
71         SkPaint paint;
72 
73         SkRect bounds = fBlob->bounds();
74         canvas->translate(20, 20);
75 
76         // Colors were chosen to map to pairs of canonical colors.  The GPU Backend will cache A8
77         // Texture Blobs based on the canonical color they map to.  Canonical colors are used to
78         // create masks.  For A8 there are 8 of them.
79         //SkColor colors[] = {SK_ColorCYAN, SK_ColorLTGRAY, SK_ColorYELLOW, SK_ColorWHITE};
80 
81         SkScalar xOffset = SkScalarCeilToScalar(bounds.width());
82         SkScalar yOffset = SkScalarCeilToScalar(bounds.height());
83         // first translate
84         canvas->translate(xOffset, 2 * yOffset);
85         canvas->drawTextBlob(fBlob, 0, 0, paint);
86         canvas->translate(-xOffset, 0);
87         canvas->drawTextBlob(fBlob, 0, 0, paint);
88         canvas->translate(2 * xOffset, 0);
89         canvas->drawTextBlob(fBlob, 0, 0, paint);
90         canvas->translate(-xOffset, -yOffset);
91         canvas->drawTextBlob(fBlob, 0, 0, paint);
92         canvas->translate(0, 2 * yOffset);
93         canvas->drawTextBlob(fBlob, 0, 0, paint);
94 
95         // now rotate
96         canvas->translate(4 * xOffset, -yOffset);
97         canvas->rotate(180.f);
98         canvas->drawTextBlob(fBlob, 0, 0, paint);
99         canvas->rotate(-180.f);
100         canvas->translate(0, -yOffset);
101         canvas->rotate(-180.f);
102         canvas->drawTextBlob(fBlob, 0, 0, paint);
103         canvas->rotate(270.f);
104         canvas->drawTextBlob(fBlob, 0, 0, paint);
105         canvas->rotate(-90.f);
106         canvas->translate(-xOffset, yOffset);
107         canvas->rotate(-90.f);
108         canvas->drawTextBlob(fBlob, 0, 0, paint);
109         canvas->rotate(90.f);
110 
111         // and scales
112         canvas->translate(- 3 * xOffset, 3 * yOffset);
113         canvas->scale(1.5f, 1.5f);
114         canvas->drawTextBlob(fBlob, 0, 0, paint);
115         canvas->translate(xOffset, 0);
116         canvas->scale(.25f, .25f);
117         canvas->drawTextBlob(fBlob, 0, 0, paint);
118         canvas->translate(xOffset, 0);
119         canvas->scale(3.f, 2.f);
120         canvas->drawTextBlob(fBlob, 0, 0, paint);
121 
122         // finally rotates, scales, and translates together
123         canvas->translate(xOffset, 0);
124         canvas->rotate(23.f);
125         canvas->scale(.33f, .5f);
126         canvas->drawTextBlob(fBlob, 0, 0, paint);
127 
128         canvas->rotate(-46.f);
129         canvas->translate(xOffset, 0);
130         canvas->scale(1.2f, 1.1f);
131         canvas->drawTextBlob(fBlob, 0, 0, paint);
132 
133         canvas->rotate(46.f);
134         canvas->translate(xOffset, 0);
135         canvas->scale(1.1f, 1.2f);
136         canvas->drawTextBlob(fBlob, 0, 0, paint);
137 
138         canvas->rotate(46.f);
139         canvas->translate(xOffset, 0);
140         canvas->scale(.95f, 1.1f);
141         canvas->drawTextBlob(fBlob, 0, 0, paint);
142 
143         canvas->rotate(46.f);
144         canvas->translate(xOffset, 0);
145         canvas->scale(1.3f, .7f);
146         canvas->drawTextBlob(fBlob, 0, 0, paint);
147 
148         canvas->rotate(46.f);
149         canvas->translate(xOffset, 0);
150         canvas->scale(.8f, 1.1f);
151         canvas->drawTextBlob(fBlob, 0, 0, paint);
152 
153         canvas->rotate(10.f);
154         canvas->translate(xOffset, 0);
155         canvas->scale(1.f, 5.f);
156         canvas->drawTextBlob(fBlob, 0, 0, paint);
157 
158         canvas->rotate(5.f);
159         canvas->translate(xOffset, 0);
160         canvas->scale(5.f, 1.f);
161         canvas->drawTextBlob(fBlob, 0, 0, paint);
162     }
163 
164 private:
165     sk_sp<SkTextBlob> fBlob;
166 
167     inline static constexpr int kWidth = 1000;
168     inline static constexpr int kHeight = 1200;
169 
170     using INHERITED = GM;
171 };
172 
173 //////////////////////////////////////////////////////////////////////////////
174 
175 DEF_GM(return new TextBlobTransforms;)
176 }  // namespace skiagm
177