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The PSL1GHT font library provides functions for loading and rendering TrueType fonts using the system’s font rendering engine. It supports both system fonts and custom font files.

​
Font System Overview

The font library consists of several components:
  • Font Library: Manages font resources and rendering
  • Font Renderer: Performs glyph rasterization
  • Font Sets: Collections of fonts for different character sets
  • Glyphs: Individual character bitmaps
┌────────────────┐
│  Font Library   │
└────────┬───────┘
         │
    ┌────┼────┐
    │         │
┌───┴───┐ ┌─┴──────────┐
│  Font  │ │  Renderer  │
│ Object │ │   Engine   │
└───┬────┘ └─────┬─────┘
    │              │
    │              │
    ▼              ▼
┌────────┐  ┌────────┐
│ Glyphs │  │ Surface │
└────────┘  └────────┘

​
Initialization

1

Initialize Font System

Set up the font library:
#include <font/font.h>
#include <font/fontFT.h>

fontConfig config;
fontConfig_initialize(&config);

s32 ret = fontInit(&config);
if (ret != 0) {
    printf("Failed to initialize font library: %d\n", ret);
    return ret;
}
The fontConfig structure from font/font.h:36-46 contains:
typedef struct _font_config {
    struct {
        u32 *buffer;  // File cache buffer
        u32 size;     // Cache size
    } fileCache;
    
    u32 userFontEntryMax;      // Max user fonts
    fontEntry *userFontEntries; // User font array
    u32 flags;                  // Configuration flags
} fontConfig;
2

Create Font Library

Initialize a font library instance:
fontLibrary *lib;

ret = fontCreateLibrary(NULL, &lib);
if (ret != 0) {
    printf("Failed to create font library: %d\n", ret);
    return ret;
}
3

Create Font Renderer

Set up the rendering engine:
fontRenderer *renderer;
fontRendererConfig rconfig;

// Configure renderer buffer
rconfig.bufferingPolicy.buffer = NULL;
rconfig.bufferingPolicy.initSize = 1024 * 1024;   // 1MB
rconfig.bufferingPolicy.maxSize = 4 * 1024 * 1024; // 4MB
rconfig.bufferingPolicy.expandSize = 512 * 1024;  // 512KB
rconfig.bufferingPolicy.resetSize = 2 * 1024 * 1024; // 2MB

ret = fontCreateRenderer(lib, &rconfig, &renderer);
if (ret != 0) {
    printf("Failed to create renderer: %d\n", ret);
    return ret;
}

​
Opening Fonts

You can open fonts from system font sets or from files.

​
System Fonts

#include <font/fontset.h>

font f;
fontType type;

// Set font type (Japanese, Latin, etc.)
type.type = FONT_TYPE_DEFAULT;
type.map = FONT_MAP_UNICODE;

// Open from system font set
ret = fontOpenFontset(lib, &type, &f);
if (ret != 0) {
    printf("Failed to open font set: %d\n", ret);
    return ret;
}

// Bind renderer to font
fontBindRenderer(&f, renderer);

​
Font Types

Common font types from font/fontset.h: 
FONT_TYPE_DEFAULT      // Default system font
FONT_TYPE_LATIN        // Latin character set
FONT_TYPE_JAPANESE     // Japanese characters
FONT_TYPE_KOREAN       // Korean characters
FONT_TYPE_CHINESE_S    // Simplified Chinese
FONT_TYPE_CHINESE_T    // Traditional Chinese

​
Custom Font Files

Load fonts from TTF files: 
font f;
const char *fontPath = "/dev_hdd0/game/fonts/myfont.ttf";
u32 subNum = 0;      // Font index in collection (0 for single fonts)
s32 uniqueID = -1;   // Unique ID (-1 for automatic)

ret = fontOpenFontFile(lib, fontPath, subNum, uniqueID, &f);
if (ret != 0) {
    printf("Failed to open font file: %d\n", ret);
    return ret;
}

fontBindRenderer(&f, renderer);

​
Font from Memory

Load a font from memory: 
void *fontData = /* ... loaded font data ... */;
u32 fontSize = /* ... size in bytes ... */;

ret = fontOpenFontMemory(lib, fontData, fontSize, subNum, uniqueID, &f);
if (ret != 0) {
    printf("Failed to open font from memory: %d\n", ret);
    return ret;
}

fontBindRenderer(&f, renderer);

​
Configuring Font Size

Set the font size before rendering:

​
Point Size

f32 width = 24.0f;   // Point size
f32 height = 24.0f;

// Set size in points
fontSetScalePoint(&f, width, height);

// Or for rendering (temporary override)
fontSetupRenderScalePoint(&f, width, height);

​
Pixel Size

f32 width = 32.0f;   // Pixel size
f32 height = 32.0f;

// Set size in pixels
fontSetScalePixel(&f, width, height);

// Or for rendering
fontSetupRenderScalePixel(&f, width, height);

​
DPI Resolution

Set resolution for point-to-pixel conversion: 
u32 hDpi = 72;  // Horizontal DPI
u32 vDpi = 72;  // Vertical DPI

fontSetResolutionDpi(&f, hDpi, vDpi);

​
Rendering Text

​
Creating a Render Surface

Define where glyphs will be rendered: 
fontRenderSurface surface;

// Surface buffer (ARGB or grayscale)
u32 width = 1920;
u32 height = 1080;
u32 pitch = width * 4;  // 4 bytes per pixel for ARGB
void *buffer = malloc(pitch * height);

// Initialize surface
fontRenderSurfaceInit(&surface,
                     buffer,           // Buffer pointer
                     pitch,            // Pitch in bytes
                     4,                // Bytes per pixel
                     width, height);   // Dimensions

// Set scissor rectangle (optional)
fontRenderSurfaceSetScissor(&surface, 0, 0, width, height);

​
Rendering a Character

Render a single character glyph: 
u32 code = 'A';  // Character code (Unicode)
f32 x = 100.0f;  // X position
f32 y = 100.0f;  // Y position
fontGlyphMetrics metrics;

ret = fontRenderCharGlyphImage(&f, code, &surface, x, y,
                               &metrics, NULL);
if (ret != 0) {
    printf("Failed to render character: %d\n", ret);
}

​
Rendering a String

Render multiple characters: 
void renderString(font *f, fontRenderSurface *surface,
                 const char *text, f32 x, f32 y) {
    f32 pen_x = x;
    f32 pen_y = y;
    
    while (*text) {
        u32 code = (u32)*text++;
        fontGlyphMetrics metrics;
        
        // Render character
        s32 ret = fontRenderCharGlyphImage(f, code, surface,
                                           pen_x, pen_y,
                                           &metrics, NULL);
        if (ret == 0) {
            // Advance pen position
            pen_x += metrics.horizontal.advance;
        }
    }
}

​
Glyph Metrics

The fontGlyphMetrics structure provides glyph dimensions: 
// From font/font.h:95-110
typedef struct _font_glyph_metrics {
    f32 width;   // Glyph width
    f32 height;  // Glyph height
    
    struct {
        f32 bearingX;  // Horizontal bearing X
        f32 bearingY;  // Horizontal bearing Y
        f32 advance;   // Horizontal advance
    } horizontal;
    
    struct {
        f32 bearingX;  // Vertical bearing X
        f32 bearingY;  // Vertical bearing Y
        f32 advance;   // Vertical advance
    } vertical;
} fontGlyphMetrics;

​
Getting Metrics Without Rendering

u32 code = 'A';
fontGlyphMetrics metrics;

// Get horizontal metrics
ret = fontGetCharGlyphMetrics(&f, code, &metrics);

// Get vertical metrics (for vertical text)
ret = fontGetCharGlyphMetricsVertical(&f, code, &metrics);

printf("Width: %.2f, Height: %.2f\n", metrics.width, metrics.height);
printf("Advance: %.2f\n", metrics.horizontal.advance);

​
Measuring Text Width

f32 measureText(font *f, const char *text) {
    f32 width = 0.0f;
    
    while (*text) {
        u32 code = (u32)*text++;
        fontGlyphMetrics metrics;
        
        if (fontGetRenderCharGlyphMetrics(f, code, &metrics) == 0) {
            width += metrics.horizontal.advance;
        }
    }
    
    return width;
}

​
Layout Information

Get font layout properties:

​
Horizontal Layout

fontHorizontalLayout layout;

ret = fontGetHorizontalLayout(&f, &layout);
if (ret == 0) {
    printf("Baseline Y: %.2f\n", layout.baseLineY);
    printf("Line height: %.2f\n", layout.lineHeight);
    printf("Effect height: %.2f\n", layout.effectHeight);
}

​
Vertical Layout

fontVerticalLayout layout;

ret = fontGetVerticalLayout(&f, &layout);
if (ret == 0) {
    printf("Baseline X: %.2f\n", layout.baseLineX);
    printf("Line width: %.2f\n", layout.lineWidth);
    printf("Effect width: %.2f\n", layout.effectWidth);
}

​
Kerning

Kerning adjusts spacing between specific character pairs: 
u32 prevCode = 'A';
u32 currCode = 'V';
fontKerning kerning;

ret = fontGetKerning(&f, prevCode, currCode, &kerning);
if (ret == 0) {
    printf("Kerning offset X: %.2f\n", kerning.offsetX);
    printf("Kerning offset Y: %.2f\n", kerning.offsetY);
}

​
Rendering with Kerning

void renderStringWithKerning(font *f, fontRenderSurface *surface,
                             const char *text, f32 x, f32 y) {
    f32 pen_x = x;
    f32 pen_y = y;
    u32 prevCode = 0;
    
    while (*text) {
        u32 code = (u32)*text++;
        
        // Apply kerning
        if (prevCode != 0) {
            fontKerning kerning;
            if (fontGetRenderScaledKerning(f, prevCode, code,
                                          &kerning) == 0) {
                pen_x += kerning.offsetX;
                pen_y += kerning.offsetY;
            }
        }
        
        // Render character
        fontGlyphMetrics metrics;
        fontRenderCharGlyphImage(f, code, surface, pen_x, pen_y,
                                &metrics, NULL);
        
        // Advance
        pen_x += metrics.horizontal.advance;
        prevCode = code;
    }
}

​
Font Effects

Apply weight and slant effects:

​
Weight (Bold)

f32 weight = 0.5f;  // Additional weight (0.0 = normal)

// Set permanently
fontSetEffectWeight(&f, weight);

// Or for rendering only
fontSetupRenderEffectWeight(&f, weight);

​
Slant (Italic)

f32 slant = 0.3f;  // Slant factor (0.0 = no slant)

// Set permanently
fontSetEffectSlant(&f, slant);

// Or for rendering only
fontSetupRenderEffectSlant(&f, slant);

​
Advanced Rendering

​
Generating Glyph Outlines

Get vector outline data: 
u32 code = 'A';
fontGlyph *glyph;

// Generate glyph with outline
ret = fontGenerateCharGlyph(&f, code, &glyph);
if (ret == 0) {
    fontGlyphOutline *outline = &glyph->outline;
    
    printf("Contours: %d\n", outline->contoursCount);
    printf("Points: %d\n", outline->pointsCount);
    
    // Access outline points
    for (int i = 0; i < outline->pointsCount; i++) {
        printf("Point %d: (%.2f, %.2f) tag=%d\n",
               i, outline->Points[i].x, outline->Points[i].y,
               outline->pointTags[i]);
    }
    
    // Free glyph when done
    fontDeleteGlyph(&f, glyph);
}

​
Custom Glyph Rendering

Render with custom style: 
fontGlyph *glyph;
fontGlyphStyle style;

// Configure style
style.Scale.widthPixel = 32.0f;
style.Scale.heightPixel = 32.0f;
style.Effect.weight = 0.0f;
style.Effect.slant = 0.0f;

// Generate glyph
fontGenerateCharGlyph(&f, 'A', &glyph);

// Render with custom style
fontGlyphMetrics metrics;
fontGlyphRenderImage(glyph, &style, renderer, &surface,
                    x, y, &metrics, NULL);

// Cleanup
fontDeleteGlyph(&f, glyph);

​
Complete Example

#include <font/font.h>
#include <font/fontFT.h>
#include <font/fontset.h>

font f;
fontRenderer *renderer;
fontLibrary *lib;

int initFonts() {
    // Initialize font system
    fontConfig config;
    fontConfig_initialize(&config);
    
    if (fontInit(&config) != 0) return -1;
    
    // Create library
    if (fontCreateLibrary(NULL, &lib) != 0) return -1;
    
    // Create renderer
    fontRendererConfig rconfig;
    rconfig.bufferingPolicy.buffer = NULL;
    rconfig.bufferingPolicy.initSize = 1024 * 1024;
    rconfig.bufferingPolicy.maxSize = 4 * 1024 * 1024;
    rconfig.bufferingPolicy.expandSize = 512 * 1024;
    rconfig.bufferingPolicy.resetSize = 2 * 1024 * 1024;
    
    if (fontCreateRenderer(lib, &rconfig, &renderer) != 0) return -1;
    
    // Open system font
    fontType type;
    type.type = FONT_TYPE_DEFAULT;
    type.map = FONT_MAP_UNICODE;
    
    if (fontOpenFontset(lib, &type, &f) != 0) return -1;
    
    // Bind renderer
    fontBindRenderer(&f, renderer);
    
    // Set font size
    fontSetScalePixel(&f, 24.0f, 24.0f);
    
    return 0;
}

void renderText(void *framebuffer, u32 width, u32 height,
               const char *text, f32 x, f32 y) {
    // Create surface
    fontRenderSurface surface;
    fontRenderSurfaceInit(&surface, framebuffer, width * 4, 4,
                         width, height);
    
    // Render string
    f32 pen_x = x;
    f32 pen_y = y;
    u32 prevCode = 0;
    
    while (*text) {
        u32 code = (u32)*text++;
        
        // Apply kerning
        if (prevCode) {
            fontKerning kerning;
            fontGetRenderScaledKerning(&f, prevCode, code, &kerning);
            pen_x += kerning.offsetX;
        }
        
        // Render
        fontGlyphMetrics metrics;
        fontRenderCharGlyphImage(&f, code, &surface,
                                pen_x, pen_y, &metrics, NULL);
        
        pen_x += metrics.horizontal.advance;
        prevCode = code;
    }
}

void shutdownFonts() {
    fontUnbindRenderer(&f);
    fontCloseFont(&f);
    fontDestroyRenderer(renderer);
    fontEndLibrary(lib);
    fontEnd();
}

​
Integrating with RSX

To display font-rendered text on screen: 
// 1. Create texture from font surface
u32 *text_texture = (u32*)rsxMemalign(128, width * height * 4);

// 2. Render text to CPU buffer
void *cpu_buffer = malloc(width * height * 4);
fontRenderSurface surface;
fontRenderSurfaceInit(&surface, cpu_buffer, width * 4, 4,
                     width, height);
renderText(&surface, "Hello World", 0, 0);

// 3. Copy to RSX texture
memcpy(text_texture, cpu_buffer, width * height * 4);
free(cpu_buffer);

// 4. Use as texture in rendering
u32 tex_offset;
rsxAddressToOffset(text_texture, &tex_offset);

gcmTexture texture;
texture.format = GCM_TEXTURE_FORMAT_A8R8G8B8 | GCM_TEXTURE_FORMAT_LIN;
texture.width = width;
texture.height = height;
texture.offset = tex_offset;
// ... configure texture and render

​
Memory Management

Cleanup when done: 
// Unbind renderer
fontUnbindRenderer(&f);

// Close font
fontCloseFont(&f);

// Destroy renderer
fontDestroyRenderer(renderer);

// End library
fontEndLibrary(lib);

// Shutdown font system
fontEnd();

​
API Reference

Initialize the font system.
s32 fontInit(fontConfig *config);
Open a font from file.
s32 fontOpenFontFile(const fontLibrary *lib,
                    const char *fontPath,
                    u32 subNum, s32 uniqueID, font *f);
Render a character glyph.
s32 fontRenderCharGlyphImage(font *f, u32 code,
                            fontRenderSurface *surface,
                            f32 x, f32 y,
                            fontGlyphMetrics *metrics,
                            fontImageTransInfo *transInfo);
Get glyph metrics without rendering.
s32 fontGetCharGlyphMetrics(font *f, u32 code,
                           fontGlyphMetrics *metrics);
Set font size in pixels.
s32 fontSetScalePixel(font *f, f32 w, f32 h);

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