BackendFont.hpp

//
// TGUI - Texus' Graphical User Interface
// Copyright (C) 2012-2026 Bruno Van de Velde (vdv_b@tgui.eu)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
//    you must not claim that you wrote the original software.
//    If you use this software in a product, an acknowledgment
//    in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
//    and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
 
#ifndef TGUI_BACKEND_FONT_HPP
#define TGUI_BACKEND_FONT_HPP
 
#include <TGUI/Global.hpp>
 
#include <TGUI/Backend/Renderer/BackendTexture.hpp>
 
#include <TGUI/Font.hpp>
#include <TGUI/String.hpp>
 
#include <cstdint>

 
namespace tgui
{
    class TGUI_API BackendFont
    {
    public:
        BackendFont();

        BackendFont(const BackendFont& other);

        BackendFont(BackendFont&& other) noexcept;

        virtual ~BackendFont();

        BackendFont& operator=(const BackendFont& other);

        BackendFont& operator=(BackendFont&& other) noexcept;

        [[nodiscard]] virtual bool loadFromFile(const String& filename);

        [[nodiscard]] virtual bool loadFromMemory(std::unique_ptr<std::uint8_t[]> data, std::size_t sizeInBytes) = 0;

        [[nodiscard]] bool loadFromMemory(const void* data, std::size_t sizeInBytes);

        [[nodiscard]] virtual bool hasGlyph(char32_t codePoint) const = 0;

        [[nodiscard]] virtual FontGlyph getGlyph(char32_t codePoint, unsigned int characterSize, bool bold, float outlineThickness = 0) = 0;

        [[nodiscard]] virtual float getKerning(char32_t first, char32_t second, unsigned int characterSize, bool bold) = 0;

        [[nodiscard]] virtual float getLineSpacing(unsigned int characterSize) = 0;

        [[nodiscard]] virtual float getFontHeight(unsigned int characterSize) = 0;

        [[nodiscard]] virtual float getAscent(unsigned int characterSize) = 0;

        [[nodiscard]] virtual float getDescent(unsigned int characterSize) = 0;

        [[nodiscard]] virtual float getUnderlinePosition(unsigned int characterSize) = 0;

        [[nodiscard]] virtual float getUnderlineThickness(unsigned int characterSize) = 0;

        [[nodiscard]] virtual std::shared_ptr<BackendTexture> getTexture(unsigned int characterSize, unsigned int& textureVersion) = 0;

        [[nodiscard]] virtual Vector2u getTextureSize(unsigned int characterSize) = 0;

        virtual void setSmooth(bool smooth);

        [[nodiscard]] bool isSmooth() const;

        virtual void setFontScale(float scale);

        [[nodiscard]] float getFontScale() const;

 
    protected:
        [[nodiscard]] static std::uint64_t constructGlyphKey(char32_t codePoint, unsigned int characterSize, bool bold, float outlineThickness);

 
    protected:
        bool m_isSmooth = true;
        float m_fontScale = 1;
    };
} // namespace tgui
 
#endif // TGUI_BACKEND_FONT_HPP