Add support for 180/270 degrees rotation.
diff --git a/include/ui/ISurface.h b/include/ui/ISurface.h
index b37a8ac..c7f181c 100644
--- a/include/ui/ISurface.h
+++ b/include/ui/ISurface.h
@@ -55,8 +55,11 @@
     class BufferHeap {
     public:
         enum {
-            /* rotate source image 90 degrees */
+            /* rotate source image */
+            ROT_0     = 0,
             ROT_90    = HAL_TRANSFORM_ROT_90,
+            ROT_180   = HAL_TRANSFORM_ROT_180,
+            ROT_270   = HAL_TRANSFORM_ROT_270,
         };
         BufferHeap();