FontCache::FontCacheManager Class Reference

#include <FontCache.h>

Public Member Functions
TTF_Font *	GetFont (const FontCacheKey &key, const std::string &full_path)
void	ReleaseFont (const FontCacheKey &key)
void	GetStats (int &unique_fonts, int &total_refs, int &cache_hits, int &cache_misses)
void	PrintCache ()
	Print cache contents to stdout (for debugging)

Static Public Member Functions
static FontCacheManager &	GetInstance ()
	Get singleton instance.

Detailed Description

Singleton font cache manager Eliminates duplicate TTF_Font objects for fonts that differ only in color

Example: font_red = MakeFont("DejaVuSans.ttf", normal, 24, red, white) font_blue = MakeFont("DejaVuSans.ttf", normal, 24, blue, white)

Without cache: 2 separate TTF_Font objects (~66KB) With cache: 1 shared TTF_Font object (~33KB) - 50% memory savings

The cache automatically manages TTF_Font lifecycle via reference counting.

Definition at line 46 of file FontCache.h.

Member Function Documentation

GetFont()

TTF_Font * FontCache::FontCacheManager::GetFont	(	const FontCacheKey &	key,
		const std::string &	full_path
	)

Get or create TTF_Font for given key

Parameters

key	Font cache key (filename, style, size)
full_path	Full filesystem path to font file

Returns

TTF_Font pointer (may be shared), or nullptr on error

If font already in cache, increments ref count and returns existing font. Otherwise, loads font from disk, adds to cache, and returns new font.

Definition at line 42 of file FontCache.cpp.

                                                                                       {
    // Look for font in cache
    auto it = mCache.find(key);
 
    if (it != mCache.end()) {
        // Cache hit - font already loaded, increment ref count
        it->second.ref_count++;
        mCacheHits++;
        return it->second.ttf_font;
    }
 
    // Cache miss - need to load font from disk
    mCacheMisses++;
 
    // Load font directly using TTF_OpenFont (no RWops/buffer needed)
    // Modern systems can handle many open file descriptors
    TTF_Font* new_font = TTF_OpenFont(full_path.c_str(), key.size);
 
    if (!new_font) {
        std::cerr << "[FontCache] ERROR: Failed to load font: " << full_path
                  << " - " << TTF_GetError() << std::endl;
        return nullptr;
    }
 
    // Set font style (bold, italic, etc.)
    TTF_SetFontStyle(new_font, key.style);
 
    // Add to cache with ref count = 1
    mCache.insert(std::make_pair(key, CachedTTFFont(new_font)));
 
    return new_font;
}

References FontCache::FontCacheKey::size, and FontCache::FontCacheKey::style.

Referenced by PlatformFont::PlatformFont(), PlatformFont::PlatformFont(), PlatformFont::SetFontSize(), and PlatformFont::SetFontStyle().

GetInstance()

FontCacheManager & FontCache::FontCacheManager::GetInstance ( )

static

Get singleton instance.

Definition at line 33 of file FontCache.cpp.

                                                {
    static FontCacheManager instance;
    return instance;
}

Referenced by PlatformFont::PlatformFont(), PlatformFont::PlatformFont(), PlatformFont::SetFontSize(), PlatformFont::SetFontStyle(), and PlatformFont::~PlatformFont().

GetStats()

void FontCache::FontCacheManager::GetStats	(	int &	unique_fonts,
		int &	total_refs,
		int &	cache_hits,
		int &	cache_misses
	)

Get cache statistics for debugging

Parameters

unique_fonts	Number of unique TTF_Font objects in cache
total_refs	Total reference count across all fonts
cache_hits	Number of cache hits since program start
cache_misses	Number of cache misses since program start

Definition at line 119 of file FontCache.cpp.

                                                                     {
    unique_fonts = mCache.size();
    total_refs = 0;
 
    // Sum up all reference counts
    for (const auto& pair : mCache) {
        total_refs += pair.second.ref_count;
    }
 
    cache_hits = mCacheHits;
    cache_misses = mCacheMisses;
}

PrintCache()

void FontCache::FontCacheManager::PrintCache

(

)

Print cache contents to stdout (for debugging)

Definition at line 137 of file FontCache.cpp.

                                  {
    std::cout << "\n=== Font Cache Contents ===" << std::endl;
    std::cout << "Unique fonts in cache: " << mCache.size() << std::endl;
    std::cout << "Total cache hits: " << mCacheHits << std::endl;
    std::cout << "Total cache misses: " << mCacheMisses << std::endl;
 
    if (mCache.empty()) {
        std::cout << "(cache is empty)" << std::endl;
    } else {
        std::cout << "\nCached fonts:" << std::endl;
        for (const auto& pair : mCache) {
            std::cout << "  " << pair.first.filename
                      << " (style=" << pair.first.style
                      << ", size=" << pair.first.size
                      << ") refs=" << pair.second.ref_count << std::endl;
        }
    }
    std::cout << "==========================\n" << std::endl;
}

ReleaseFont()

void FontCache::FontCacheManager::ReleaseFont

(

const FontCacheKey &

key

)

Release font reference

Parameters

key	Font cache key

Decrements ref count. If ref count reaches 0, closes TTF_Font and removes from cache. Should be called from PlatformFont destructor.

Definition at line 79 of file FontCache.cpp.

                                                          {
    auto it = mCache.find(key);
 
    if (it == mCache.end()) {
        // This shouldn't happen if PlatformFont is correctly managing keys
        std::cerr << "[FontCache] WARNING: Attempted to release non-cached font: "
                  << key.filename << " (style=" << key.style << ", size=" << key.size << ")"
                  << std::endl;
        return;
    }
 
    // Decrement ref count
    it->second.ref_count--;
 
    #ifdef FONT_CACHE_DEBUG
    std::cout << "[FontCache] RELEASE: " << key.filename
              << " (style=" << key.style << ", size=" << key.size << ")"
              << " refs=" << it->second.ref_count << std::endl;
    #endif
 
    // If no more references, close font and remove from cache
    if (it->second.ref_count <= 0) {
        if (it->second.ttf_font) {
            TTF_CloseFont(it->second.ttf_font);
        }
 
        #ifdef FONT_CACHE_DEBUG
        std::cout << "[FontCache] DELETED: " << key.filename
                  << " (style=" << key.style << ", size=" << key.size << ")"
                  << " cache_size=" << (mCache.size() - 1) << std::endl;
        #endif
 
        mCache.erase(it);
    }
}

References FontCache::FontCacheKey::filename, FontCache::FontCacheKey::size, and FontCache::FontCacheKey::style.

Referenced by PlatformFont::SetFontSize(), PlatformFont::SetFontStyle(), and PlatformFont::~PlatformFont().

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The documentation for this class was generated from the following files:

• FontCache.h
• FontCache.cpp