Use sc_ prefix for size, position and point

app/src/coords.h

@@ -3,22 +3,22 @@
 
 #include <stdint.h>
 
-struct size {
+struct sc_size {
     uint16_t width;
     uint16_t height;
 };
 
-struct point {
+struct sc_point {
     int32_t x;
     int32_t y;
 };
 
-struct position {
+struct sc_position {
     // The video screen size may be different from the real device screen size,
     // so store to which size the absolute position apply, to scale it
     // accordingly.
-    struct size screen_size;
-    struct point point;
+    struct sc_size screen_size;
+    struct sc_point point;
 };
 
 #endif