Port cable_car_util from Ruby

src/cable_car_util.c

@@ -0,0 +1,38 @@
+#include "global.h"
+
+void CableCarUtil_FillWrapped(void *dest, u16 value, u8 left, u8 top, u8 width, u8 height)
+{
+    u8 i;
+    u8 j;
+    u8 x;
+    u8 y;
+
+    for (i = 0, y = top; i < height; i++)
+    {
+        for (x = left, j = 0; j < width; j++)
+        {
+            *(u16 *)&((u8 *)dest)[y * 64 + x * 2] = value;
+            x = (x + 1) % 32;
+        }
+        y = (y + 1) % 32;
+    }
+}
+
+void CableCarUtil_CopyWrapped(void *dest, const u16 *src, u8 left, u8 top, u8 width, u8 height)
+{
+    u8 i;
+    u8 j;
+    u8 x;
+    u8 y;
+    const u16 *_src;
+
+    for (i = 0, _src = src, y = top; i < height; i++)
+    {
+        for (x = left, j = 0; j < width; j++)
+        {
+            *(u16 *)&((u8 *)dest)[y * 64 + x * 2] = *_src++;
+            x = (x + 1) % 32;
+        }
+        y = (y + 1) % 32;
+    }
+}