add fb_fill()

src/fb.c

@@ -95,3 +95,18 @@ void fb_blend_alpha8(const uint8_t * bitmap, int width, int height, int pitch, i
         target += (fb_pitch / 4u);
     }
 }
+
+void fb_fill(int x, int y, int width, int height, uint8_t r, uint8_t g, uint8_t b)
+{
+    uint32_t * target = &fb[fb_pitch * y / 4u + x];
+    uint32_t pixel = build_pixel(r, g, b);
+    /* TODO: use memset32() */
+    for (int row = 0; row < height; row++)
+    {
+        for (int col = 0; col < width; col++)
+        {
+            target[col] = pixel;
+        }
+        target += fb_pitch / 4u;
+    }
+}

src/fb.h

@@ -7,5 +7,6 @@
 void fb_init(uint32_t * addr, uint32_t width, uint32_t height, uint32_t pitch);
 bool fb_ready(void);
 void fb_blend_alpha8(const uint8_t * bitmap, int width, int height, int pitch, int x, int y, uint8_t r, uint8_t g, uint8_t b);
+void fb_fill(int x, int y, int width, int height, uint8_t r, uint8_t g, uint8_t b);
 
 #endif

src/fb_text.c

@@ -0,0 +1,11 @@
+#include "fb_text.h"
+#include "kfont.h"
+#include "fb.h"
+
+void fb_text_render_char(int c, int x, int y, uint8_t r, uint8_t g, uint8_t b)
+{
+    const fontgen_char_info_t * char_info = kfont.char_infos[c];
+    y += kfont.line_height - kfont.baseline_offset - char_info->top;
+    x += char_info->left;
+    fb_blend_alpha8(char_info->bitmap, char_info->width, char_info->height, char_info->width, x, y, 0xFFu, 0x88u, 0u);
+}

src/fb_text.h

@@ -0,0 +1,8 @@
+#ifndef FB_TEXT_H
+#define FB_TEXT_H
+
+#include <stdint.h>
+
+void fb_text_render_char(int c, int x, int y, uint8_t r, uint8_t g, uint8_t b);
+
+#endif

src/hos_main.c

@@ -1,5 +1,6 @@
 #include <stdint.h>
 #include "fb.h"
+#include "fb_text.h"
 #include "mbinfo.h"
 #include "kfont.h"
 
@@ -10,6 +11,5 @@ void hos_main(uint32_t mbinfo_addr)
     {
         return;
     }
-    const fontgen_char_info_t * char_info = kfont.char_infos['H'];
-    fb_blend_alpha8(char_info->bitmap, char_info->width, char_info->height, char_info->width, 10, 10, 0xFFu, 0x88u, 0u);
+    fb_text_render_char('H', 10, 10, 0xFFu, 0x88u, 0u);
 }