font: implement font_dim

2 files changed, 46 insertions, 16 deletions

diff --git a/src/font/inc/font.h b/src/font/inc/font.h
index 524355d..b074089 100644
--- a/src/font/inc/font.h
+++ b/src/font/inc/font.h
@@ -12,6 +12,7 @@ enum font
 };
 
 int font_puts(enum font, short x, short y, const char *s);
+int font_dim(enum font f, const char *str, short *x, short *y);
 
 extern struct sprite font_sprite;
 
diff --git a/src/font/src/font.c b/src/font/src/font.c
index 765151b..1e1bb6c 100644
--- a/src/font/src/font.c
+++ b/src/font/src/font.c
@@ -5,7 +5,9 @@
 
 struct sprite font_sprite;
 
-static int renderstr(const enum font f, const short x, short y, const char *str)
+static int renderstr(const enum font f, const short x, short y,
+    const char *str, const bool render, short *const max_x,
+    short *const max_y)
 {
     static const struct cfg
     {
@@ -26,46 +28,73 @@ static int renderstr(const enum font f, const short x, short y, const char *str)
     char c;
     short rx = x;
 
+    if (max_x)
+        *max_x = rx;
+
+    if (max_y)
+        *max_y = y + cfg->fh;
+
     while ((c = *str++))
     {
         if (c == ' ')
         {
             rx += cfg->fs;
+
+            if (max_x && rx >= *max_x)
+                *max_x = rx;
+
             continue;
         }
         else if (c == '\n' || c == '\r')
         {
             rx = x;
             y += cfg->fh;
+
+            if (max_y)
+                *max_y = y;
+
             continue;
         }
 
-        sprite_get_or_ret(s, -1);
+        if (render)
+        {
+            sprite_get_or_ret(s, -1);
 
-        if (sprite_clone(cfg->s, s))
-            return -1;
+            if (sprite_clone(cfg->s, s))
+                return -1;
 
-        s->w = cfg->fw;
-        s->h = cfg->fh;
+            s->w = cfg->fw;
+            s->h = cfg->fh;
 
-        /* Substract non-printable characters (NUL to SP). */
-        const char ch = c - '!';
-        const short u = (cfg->fw * ch) % cfg->s->w;
-        const short v = cfg->fh * ((cfg->fw * ch) / cfg->s->w);
+            /* Substract non-printable characters (NUL to SP). */
+            const char ch = c - '!';
+            const short u = (cfg->fw * ch) % cfg->s->w;
+            const short v = cfg->fh * ((cfg->fw * ch) / cfg->s->w);
+
+            s->u += u;
+            s->v += v;
+            s->x = rx;
+            s->y = y;
+            sprite_sort(s);
+        }
 
-        s->u += u;
-        s->v += v;
-        s->x = rx;
-        s->y = y;
-        sprite_sort(s);
         rx += cfg->fs;
+
+        if (max_x && rx >= *max_x)
+            *max_x = rx;
     }
 
     return 0;
 }
 
+int font_dim(const enum font f, const char *const str, short *const x,
+    short *const y)
+{
+    return renderstr(f, 0, 0, str, false, x, y);
+}
+
 int font_puts(const enum font f, const short x, const short y,
     const char *const str)
 {
-    return renderstr(f, x, y, str) ? EOF : 0;
+    return renderstr(f, x, y, str, true, NULL, NULL) ? EOF : 0;
 }