TGUI  1.0-alpha
BackendFontSDLttf.hpp
1
2//
3// TGUI - Texus' Graphical User Interface
4// Copyright (C) 2012-2022 Bruno Van de Velde (vdv_b@tgui.eu)
5//
6// This software is provided 'as-is', without any express or implied warranty.
7// In no event will the authors be held liable for any damages arising from the use of this software.
8//
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10// including commercial applications, and to alter it and redistribute it freely,
11// subject to the following restrictions:
12//
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14// you must not claim that you wrote the original software.
15// If you use this software in a product, an acknowledgment
16// in the product documentation would be appreciated but is not required.
17//
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19// and must not be misrepresented as being the original software.
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22//
24
25
26#ifndef TGUI_BACKEND_FONT_SDL_TTF_HPP
27#define TGUI_BACKEND_FONT_SDL_TTF_HPP
28
29#include <TGUI/Backend/Font/BackendFont.hpp>
30#include <TGUI/extlibs/IncludeSDL.hpp>
31#include <SDL_ttf.h>
32#include <unordered_map>
33
35
36namespace tgui
37{
42 {
43 public:
44
49
50
59 virtual bool loadFromMemory(std::unique_ptr<std::uint8_t[]> data, std::size_t sizeInBytes) override;
61
62
70 bool hasGlyph(char32_t codePoint) const override;
71
72
86 virtual FontGlyph getGlyph(char32_t codePoint, unsigned int characterSize, bool bold, float outlineThickness = 0) override;
87
88
103 virtual float getKerning(char32_t first, char32_t second, unsigned int characterSize, bool bold) override;
104
105
115 virtual float getLineSpacing(unsigned int characterSize) override;
116
117
127 float getUnderlinePosition(unsigned int characterSize) override;
128
129
139 float getUnderlineThickness(unsigned int characterSize) override;
140
141
149 std::shared_ptr<BackendTexture> getTexture(unsigned int characterSize) override;
150
151
161 void setSmooth(bool smooth) override;
162
163
170 TTF_Font* getInternalFont(unsigned int characterSize);
171
172
174 private:
175
177 // Finds the location and thickness of the underline, for the getUnderlinePosition and getUnderlineThickness functions
179 std::pair<int, int> getUnderlineInfo(unsigned int characterSize);
180
181
183 // Reserves space in the texture to place the glyph
185 IntRect findAvailableGlyphRect(unsigned int width, unsigned int height);
186
187
189 private:
190
191 struct Row
192 {
193 Row(unsigned int rowTop, unsigned int rowHeight) : width(0), top(rowTop), height(rowHeight) {}
194
195 unsigned int width;
196 unsigned int top;
197 unsigned int height;
198 };
199
200 std::unique_ptr<std::uint8_t[]> m_fileContents;
201 std::size_t m_fileSize = 0;
202
203 // TTF_Font needs a character size, so we store one font per character size
204 std::unordered_map<unsigned int, TTF_Font*> m_fonts;
205 std::unordered_map<unsigned int, bool> m_lastBoldFlag;
206 std::unordered_map<unsigned int, float> m_lastOutlineThickness;
207
208 std::unordered_map<unsigned int, std::pair<int, int>> m_cachedUnderlineInfo; // character size -> (underline vertical offset, underline thickness)
209
210 std::unordered_map<std::uint64_t, FontGlyph> m_glyphs;
211 unsigned int m_nextRow = 3;
212 std::vector<Row> m_rows;
213
214 std::unique_ptr<std::uint8_t[]> m_pixels;
215 std::shared_ptr<BackendTexture> m_texture;
216 unsigned int m_textureSize = 0;
217 bool m_textureUpToDate = false;
218 };
219}
220
222
223#endif // TGUI_BACKEND_FONT_SDL_TTF_HPP
Font implementations that uses SDL_ttf to load glyphs.
Definition: BackendFontSDLttf.hpp:42
float getUnderlinePosition(unsigned int characterSize) override
Get the position of the underline.
float getUnderlineThickness(unsigned int characterSize) override
Get the thickness of the underline.
virtual float getLineSpacing(unsigned int characterSize) override
Returns the line spacing.
std::shared_ptr< BackendTexture > getTexture(unsigned int characterSize) override
Returns the texture that is used to store glyphs of the given character size.
virtual bool loadFromMemory(std::unique_ptr< std::uint8_t[]> data, std::size_t sizeInBytes) override
Loads a font from memory.
void setSmooth(bool smooth) override
Enable or disable the smooth filter.
virtual float getKerning(char32_t first, char32_t second, unsigned int characterSize, bool bold) override
Returns the kerning offset of two glyphs.
virtual FontGlyph getGlyph(char32_t codePoint, unsigned int characterSize, bool bold, float outlineThickness=0) override
Retrieve a glyph of the font.
bool hasGlyph(char32_t codePoint) const override
Returns whether a font contains a certain glyph.
~BackendFontSDLttf()
Destructor that cleans up the SDL resources.
Base class for font implementations that depend on the backend.
Definition: BackendFont.hpp:43
virtual bool loadFromMemory(std::unique_ptr< std::uint8_t[]> data, std::size_t sizeInBytes)=0
Loads a font from memory.
Namespace that contains all TGUI functions and classes.
Definition: AbsoluteOrRelativeValue.hpp:36
Information about a glyph in the font.
Definition: Font.hpp:47