feat: TrueType (TTF) font rendering, many new desktop applications and DOOM support, among other improvements

programs/include/gui/font.hpp

@@ -1,12 +1,13 @@
 /*
     * font.hpp
-    * ZenithOS 8x16 VGA bitmap font rendering
+    * ZenithOS text rendering — TrueType with bitmap fallback
     * Copyright (c) 2025 Daniel Hammer
 */
 
 #pragma once
 #include "gui/gui.hpp"
 #include "gui/framebuffer.hpp"
+#include "gui/truetype.hpp"
 
 namespace gui {
 
@@ -16,6 +17,30 @@ static constexpr int FONT_HEIGHT = 16;
 // Defined in font_data.cpp
 extern const uint8_t font_data[256 * 16];
 
+// Dynamic font height: TTF line height or 16 (bitmap fallback)
+inline int system_font_height() {
+    if (fonts::system_font && fonts::system_font->valid)
+        return fonts::system_font->get_line_height(fonts::UI_SIZE);
+    return FONT_HEIGHT;
+}
+
+// Dynamic mono font cell dimensions
+inline int mono_cell_width() {
+    if (fonts::mono && fonts::mono->valid) {
+        // Monospace: all glyphs have the same advance
+        GlyphCache* gc = fonts::mono->get_cache(fonts::TERM_SIZE);
+        CachedGlyph* g = fonts::mono->get_glyph(gc, 'M');
+        if (g) return g->advance;
+    }
+    return FONT_WIDTH;
+}
+
+inline int mono_cell_height() {
+    if (fonts::mono && fonts::mono->valid)
+        return fonts::mono->get_line_height(fonts::TERM_SIZE);
+    return FONT_HEIGHT;
+}
+
 inline void draw_char(Framebuffer& fb, int x, int y, char c, Color fg) {
     const uint8_t* glyph = &font_data[(unsigned char)c * FONT_HEIGHT];
     for (int row = 0; row < FONT_HEIGHT; row++) {
@@ -43,18 +68,29 @@ inline void draw_char_bg(Framebuffer& fb, int x, int y, char c, Color fg, Color
 }
 
 inline void draw_text(Framebuffer& fb, int x, int y, const char* text, Color fg) {
+    if (fonts::system_font && fonts::system_font->valid) {
+        fonts::system_font->draw(fb, x, y, text, fg, fonts::UI_SIZE);
+        return;
+    }
     for (int i = 0; text[i]; i++) {
         draw_char(fb, x + i * FONT_WIDTH, y, text[i], fg);
     }
 }
 
 inline void draw_text_bg(Framebuffer& fb, int x, int y, const char* text, Color fg, Color bg) {
+    if (fonts::system_font && fonts::system_font->valid) {
+        fonts::system_font->draw_bg(fb, x, y, text, fg, bg, fonts::UI_SIZE);
+        return;
+    }
     for (int i = 0; text[i]; i++) {
         draw_char_bg(fb, x + i * FONT_WIDTH, y, text[i], fg, bg);
     }
 }
 
 inline int text_width(const char* text) {
+    if (fonts::system_font && fonts::system_font->valid) {
+        return fonts::system_font->measure_text(text, fonts::UI_SIZE);
+    }
     int len = 0;
     while (text[len]) len++;
     return len * FONT_WIDTH;