tb_font_renderer.h

// ================================================================================
// ==      This file is a part of Turbo Badger. (C) 2011-2014, Emil Segerås      ==
// ==                     See tb_core.h for more information.                    ==
// ================================================================================

#ifndef TB_FONT_RENDERER_H
#define TB_FONT_RENDERER_H

#include "tb_core.h"
#include "tb_bitmap_fragment.h"
#include "tb_renderer.h"
#include "tb_tempbuffer.h"
#include "tb_linklist.h"
#include "tb_font_desc.h"
#include "utf8/utf8.h"

namespace tb {

class TBBitmap;
class TBFontFace;

class TBFontGlyphData
{
public:
    TBFontGlyphData() : data8(nullptr), data32(nullptr), w(0), h(0), stride(0), rgb(false) {}
    ~TBFontGlyphData() {}

    uint8_t *data8;
    uint32_t *data32;
    int w, h, stride;
    bool rgb;
};

class TBGlyphMetrics
{
public:
    TBGlyphMetrics() : advance(0), x(0), y(0) {}
    int16_t advance, x, y;
};

class TBFontMetrics
{
public:
    TBFontMetrics() : ascent(0), descent(0), height(0) {}
    int16_t ascent; 
    int16_t descent;    
    int16_t height; 
};

class TBFontRenderer : public TBLinkOf<TBFontRenderer>
{
public:
    virtual ~TBFontRenderer() {}

    virtual TBFontFace *Create(TBFontManager *font_manager, const TBStr & filename,
                                const TBFontDescription &font_desc) = 0;

    virtual bool RenderGlyph(TBFontGlyphData *data, UCS4 cp) = 0;
    virtual void GetGlyphMetrics(TBGlyphMetrics *metrics, UCS4 cp) = 0;
    virtual TBFontMetrics GetMetrics() = 0;
    //virtual int GetKernAdvance(UCS4 cp1, UCS4 cp2) = 0;
};

class TBFontGlyph : public TBLinkOf<TBFontGlyph>
{
public:
    TBFontGlyph(const TBID &hash_id, UCS4 cp);
    TBID hash_id;
    UCS4 cp;
    TBGlyphMetrics metrics;     
    TBBitmapFragment *frag;     
    bool has_rgb;               
};

class TBFontGlyphCache : private TBRendererListener
{
public:
    TBFontGlyphCache();
    ~TBFontGlyphCache();

    TBFontGlyph *GetGlyph(const TBID &hash_id, UCS4 cp);

    TBFontGlyph *CreateAndCacheGlyph(const TBID &hash_id, UCS4 cp);

    TBBitmapFragment *CreateFragment(TBFontGlyph *glyph, int w, int h, int stride, uint32_t *data);

#ifdef TB_RUNTIME_DEBUG_INFO

    void Debug();
#endif

    // Implementing TBRendererListener
    virtual void OnContextLost();
    virtual void OnContextRestored();
private:
    void DropGlyphFragment(TBFontGlyph *glyph);
    TBBitmapFragmentManager m_frag_manager;
    TBHashTableAutoDeleteOf<TBFontGlyph> m_glyphs;
    TBLinkListOf<TBFontGlyph> m_all_rendered_glyphs;
};

class TBFontEffect
{
public:
    TBFontEffect() : m_blur_radius(0) {}
    ~TBFontEffect() {}

    void SetBlurRadius(int blur_radius);

    bool RendersInRGB() const { return false; }

    TBFontGlyphData *Render(TBGlyphMetrics *metrics, const TBFontGlyphData *src);
private:
    // Blur data
    int m_blur_radius;
    TBTempBuffer m_kernel;
    TBTempBuffer m_blur_temp;
    TBTempBuffer m_data_dst;
};

class TBFontFace
{
public:
    TBFontFace(TBFontGlyphCache *glyph_cache, TBFontRenderer *renderer, const TBFontDescription &font_desc);
    ~TBFontFace();

    bool RenderGlyphs(const char *glyph_str, int glyph_str_len = TB_ALL_TO_TERMINATION);

    int GetAscent() const { return m_metrics.ascent; }

    int GetDescent() const { return m_metrics.descent; }

    int GetHeight() const { return m_metrics.height; }

    TBFontDescription GetFontDescription() const { return m_font_desc; }

    TBFontEffect *GetEffect() { return &m_effect; }

    void DrawString(int x, int y, const TBColor &color, const char *str, int len = TB_ALL_TO_TERMINATION);

    int GetStringWidth(const char *str, int len = TB_ALL_TO_TERMINATION);

#ifdef TB_RUNTIME_DEBUG_INFO

    void Debug();
#endif

    void SetBackgroundFont(TBFontFace *font, const TBColor &col, int xofs, int yofs);
private:
    TBID GetHashId(UCS4 cp) const;
    TBFontGlyph *GetGlyph(UCS4 cp, bool render_if_needed);
    TBFontGlyph *CreateAndCacheGlyph(UCS4 cp);
    void RenderGlyph(TBFontGlyph *glyph);
    TBFontGlyphCache *m_glyph_cache;
    TBFontRenderer *m_font_renderer;
    TBFontDescription m_font_desc;
    TBFontMetrics m_metrics;
    TBFontEffect m_effect;
    TBTempBuffer m_temp_buffer;

    TBFontFace *m_bgFont;
    int m_bgX;
    int m_bgY;
    TBColor m_bgColor;
};

class TBFontInfo
{
public:
    const TBStr & GetFilename() const { return m_filename; }

    const TBStr & GetName() const { return m_name; }

    TBID GetID() const { return m_id; }

private:
    friend class TBFontManager;
    TBFontInfo(const TBStr & filename, const TBStr & name) : m_filename(filename), m_name(name), m_id(name) {}
    TBStr m_filename;
    TBStr m_name;
    TBID m_id;
};

class TBFontManager
{
public:
    TBFontManager();
    ~TBFontManager();

    void AddRenderer(TBFontRenderer *renderer) { m_font_renderers.AddLast(renderer); }
    void RemoveRenderer(TBFontRenderer *renderer) { m_font_renderers.Remove(renderer); }

    TBFontInfo *AddFontInfo(const char *filename, const char *name);

    TBFontInfo *GetFontInfo(const TBID &id) const;

    bool HasFontFace(const TBFontDescription &font_desc) const;

    TBFontFace *GetFontFace(const TBFontDescription &font_desc);

    TBFontFace *CreateFontFace(const TBFontDescription &font_desc);

    void SetDefaultFontDescription(const TBFontDescription &font_desc) { m_default_font_desc = font_desc; }
    TBFontDescription GetDefaultFontDescription() const { return m_default_font_desc; }

    TBFontGlyphCache *GetGlyphCache() { return &m_glyph_cache; }
private:
    TBHashTableAutoDeleteOf<TBFontInfo> m_font_info;
    TBHashTableAutoDeleteOf<TBFontFace> m_fonts;
    TBLinkListAutoDeleteOf<TBFontRenderer> m_font_renderers;
    TBFontGlyphCache m_glyph_cache;
    TBFontDescription m_default_font_desc;
    TBFontDescription m_test_font_desc;
};

} // namespace tb

#endif // TB_FONT_RENDERER_H