1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef MINIKIN_FONT_H
18#define MINIKIN_FONT_H
19
20#include <memory>
21#include <string>
22
23#include <minikin/FontFamily.h>
24#include <minikin/Hyphenator.h>
25
26// An abstraction for platform fonts, allowing Minikin to be used with
27// multiple actual implementations of fonts.
28
29namespace minikin {
30
31class MinikinFont;
32
33// Possibly move into own .h file?
34// Note: if you add a field here, either add it to LayoutCacheKey or to
35// skipCache()
36struct MinikinPaint {
37 MinikinPaint()
38 : font(nullptr),
39 size(0),
40 scaleX(0),
41 skewX(0),
42 letterSpacing(0),
43 wordSpacing(0),
44 paintFlags(0),
45 fakery(),
46 hyphenEdit(),
47 fontFeatureSettings() {}
48
49 bool skipCache() const { return !fontFeatureSettings.empty(); }
50
51 MinikinFont* font;
52 float size;
53 float scaleX;
54 float skewX;
55 float letterSpacing;
56 float wordSpacing;
57 uint32_t paintFlags;
58 FontFakery fakery;
59 HyphenEdit hyphenEdit;
60 std::string fontFeatureSettings;
61};
62
63// Only a few flags affect layout, but those that do should have values
64// consistent with Android's paint flags.
65enum MinikinPaintFlags {
66 LinearTextFlag = 0x40,
67};
68
69struct MinikinRect {
70 float mLeft, mTop, mRight, mBottom;
71 bool isEmpty() const { return mLeft == mRight || mTop == mBottom; }
72 void set(const MinikinRect& r) {
73 mLeft = r.mLeft;
74 mTop = r.mTop;
75 mRight = r.mRight;
76 mBottom = r.mBottom;
77 }
78 void offset(float dx, float dy) {
79 mLeft += dx;
80 mTop += dy;
81 mRight += dx;
82 mBottom += dy;
83 }
84 void setEmpty() { mLeft = mTop = mRight = mBottom = 0; }
85 void join(const MinikinRect& r);
86};
87
88// Callback for freeing data
89typedef void (*MinikinDestroyFunc)(void* data);
90
91class MinikinFont {
92 public:
93 explicit MinikinFont(int32_t uniqueId) : mUniqueId(uniqueId) {}
94
95 virtual ~MinikinFont();
96
97 virtual float GetHorizontalAdvance(uint32_t glyph_id,
98 const MinikinPaint& paint) const = 0;
99
100 virtual void GetBounds(MinikinRect* bounds,
101 uint32_t glyph_id,
102 const MinikinPaint& paint) const = 0;
103
104 virtual hb_face_t* CreateHarfBuzzFace() const { return nullptr; }
105
106 virtual const std::vector<minikin::FontVariation>& GetAxes() const = 0;
107
108 virtual std::shared_ptr<MinikinFont> createFontWithVariation(
109 const std::vector<FontVariation>&) const {
110 return nullptr;
111 }
112
113 static uint32_t MakeTag(char c1, char c2, char c3, char c4) {
114 return ((uint32_t)c1 << 24) | ((uint32_t)c2 << 16) | ((uint32_t)c3 << 8) |
115 (uint32_t)c4;
116 }
117
118 int32_t GetUniqueId() const { return mUniqueId; }
119
120 private:
121 const int32_t mUniqueId;
122};
123
124} // namespace minikin
125
126#endif // MINIKIN_FONT_H
127