text rendering

3 files changed, 147 insertions, 8 deletions

diff --git a/dc/dc.c b/dc/dc.c
index 0d69710..bccc82f 100644
--- a/dc/dc.c
+++ b/dc/dc.c
@@ -13,6 +13,7 @@
 #define TILE_SIZE 16
 
 struct ty_image img;
+struct ty_font font;
 
 void tick(void)
 {
@@ -59,10 +60,57 @@ void tick(void)
         ty_color(0xFF, 0xF0, 0x80)
     );
 
-    ty_draw_end();
+    ty_draw_text(&font, ty_vec2i(5, SCREEN_HEIGHT - 5 - 8), "hello, world!");
 
     double frame_time = ty_get_time() - start;
-    ty_log_debug("%g ms, %g FPS", frame_time * 1000, 1.0 / frame_time);
+
+    char ms_fmt[] = "%.2g ms";
+    int ms_width = ty_font_width(&font, ms_fmt, frame_time * 1000);
+
+    ty_draw_rect(
+        (struct ty_recti){
+            5, 5,
+            ms_width, 8,
+        },
+        TY_COLOR_BLACK
+    );
+    ty_draw_text_fmt(
+        &font,
+        ty_vec2i(5, 5),
+        ms_fmt,
+        frame_time * 1000
+    );
+
+    char fps_fmt[] = "%4d fps";
+    int fps_width = ty_font_width(&font, fps_fmt, (int)(1.0 / frame_time));
+
+    ty_draw_rect(
+        (struct ty_recti){
+            5, 5 + 8,
+            fps_width, 8,
+        },
+        TY_COLOR_BLACK
+    );
+    ty_draw_text_fmt(
+        &font,
+        ty_vec2i(5, 5 + 8),
+        fps_fmt,
+        (int)(1.0 / frame_time)
+    );
+
+    ty_draw_end();
+}
+
+struct ty_image load_qoi_image(const char *path)
+{
+    qoi_desc desc;
+    void *data = qoi_read(path, &desc, 3);
+    if (!data)
+        ty_log_fatal(TY_ERR_IO, "failed to read image");
+    struct ty_image img = ty_create_image(desc.width, desc.height, data);
+    free(data);
+
+    return img;
 }
 
 int main(void)
@@ -75,21 +123,42 @@ int main(void)
     };
     ty_init(hints);
 
-    qoi_desc desc;
-    void *data = qoi_read("test_img.qoi", &desc, 3);
-    if (!data)
-        ty_log_fatal(TY_ERR_IO, "failed to read image");
-    img = ty_create_image(desc.width, desc.height, data);
-    free(data);
+    img = load_qoi_image("test_img.qoi");
+
+    char font_chars[] = 
+        "abcdefghijklmnopqrstuvwxyz0123456789"
+        "!\"'#$%&()*+,-./@[]\\^_`{}|~:;<>=? "
+    ;
+    struct ty_image font_img = load_qoi_image("font.qoi");
+
+    int glyph_height = 8;
+
+    for (int i = 0; font_chars[i] != '\0'; i++) {
+        struct ty_image glyph = ty_create_image(
+            font_img.width,
+            glyph_height,
+            font_img.data + font_img.width * glyph_height * i
+        );
+
+
+        ty_font_add_glyph(
+            &font,
+            *(uint8_t*)&font_chars[i],
+            glyph
+        );
+    }
 
     while (ty_is_game_running()) {
         int ticks = ty_tick();
         for (int i = 0; i < ticks; i++)
             tick();
+
+        ty_free_temp_allocs();
         // ty_sleep(1000 / hints.ticrate);
     }
 
     ty_free_image(img);
+    ty_free_image(font_img);
 
     ty_deinit();
     return 0;
diff --git a/teensy/teensy.h b/teensy/teensy.h
index 1f082f9..0b7829c 100644
--- a/teensy/teensy.h
+++ b/teensy/teensy.h
@@ -1,6 +1,8 @@
 #ifndef TEENSY_H_
 #define TEENSY_H_
 
+#include <limits.h>
+
 #include "teensy_common.h"
 #include "teensy_context.h"
 #include "teensy_list.h"
@@ -68,6 +70,10 @@ struct ty_image {
     int height;
 };
 
+struct ty_font {
+    struct ty_image glyphs[CHAR_MAX];
+};
+
 struct ty_renderer {
     struct ty_image screen;
 };
@@ -92,6 +98,9 @@ void ty_img_set_pixel(
     struct ty_color color
 );
 
+void ty_font_add_glyph(struct ty_font *font, uint8_t c, struct ty_image img);
+int ty_font_width(struct ty_font *font, const char *fmt, ...);
+
 void ty_draw_clear(struct ty_color col);
 void ty_draw_image(struct ty_image img, struct ty_vec2i pos);
 void ty_draw_image_ex(
@@ -105,6 +114,13 @@ void ty_draw_line(
     struct ty_vec2i end,
     struct ty_color color
 );
+void ty_draw_text(struct ty_font *font, struct ty_vec2i pos, const char *text);
+void ty_draw_text_fmt(
+    struct ty_font *font,
+    struct ty_vec2i pos,
+    const char *fmt,
+    ...
+);
 void ty_draw_end(void);
 
 void ty_sleep(uint64_t ms);
diff --git a/teensy/teensy_renderer.c b/teensy/teensy_renderer.c
index b29e485..b51d2a9 100644
--- a/teensy/teensy_renderer.c
+++ b/teensy/teensy_renderer.c
@@ -3,6 +3,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <math.h>
+#include <stdarg.h>
 
 #include "teensy_context.h"
 #include "teensy_list.h"
@@ -91,6 +92,31 @@ void ty_img_set_pixel(
     img.data[pos.y * img.width + pos.x] = color;
 }
 
+// This function technically is not needed, but I may want unicode support in
+// the future, when an abstraction like this is needed.
+void ty_font_add_glyph(struct ty_font *font, uint8_t c, struct ty_image img)
+{
+    font->glyphs[c] = img;
+}
+
+int ty_font_width(struct ty_font *font, const char *fmt, ...)
+{
+    va_list args;
+    va_start(args, fmt);
+    int len = vsnprintf(NULL, 0, fmt, args);
+    char *text = ty_talloc(sizeof(char) * (len + 1));
+    va_end(args);
+
+    va_start(args, fmt);
+    vsnprintf(text, len + 1, fmt, args);
+    va_end(args);
+
+    int width = 0;
+    for (uint8_t *c = (uint8_t*)text; *c != '\0'; c++)
+        width += font->glyphs[*c].width;
+    return width;
+}
+
 void ty_draw_clear(struct ty_color col)
 {
     assert(is_renderer_init());
@@ -211,6 +237,34 @@ void ty_draw_line(
     }
 }
 
+void ty_draw_text(struct ty_font *font, struct ty_vec2i pos, const char *text)
+{
+    for (const uint8_t *c = (const uint8_t*)text; *c != '\0'; c++) {
+        struct ty_image glyph = font->glyphs[*c];
+        ty_draw_image(glyph, pos);
+        pos.x += glyph.width;
+    }
+}
+
+void ty_draw_text_fmt(
+    struct ty_font *font,
+    struct ty_vec2i pos,
+    const char *fmt,
+    ...
+) {
+    va_list args;
+    va_start(args, fmt);
+    int len = vsnprintf(NULL, 0, fmt, args);
+    char *text = ty_talloc(sizeof(char) * (len + 1));
+    va_end(args);
+
+    va_start(args, fmt);
+    vsnprintf(text, len + 1, fmt, args);
+    va_end(args);
+
+    ty_draw_text(font, pos, text);
+}
+
 void ty_draw_end(void)
 {
     assert(is_renderer_init());