1 files changed, 11 insertions, 0 deletions
diff --git a/js/blit.js b/js/blit.js
index 2e41f5c..b434742 100644
--- a/js/blit.js
+++ b/js/blit.js
@@ -78,6 +78,17 @@ var blit = (function(){
       }
     })
   }
+  blit.inverted_cross = function(A, lex){
+    // 1x1 brush should still draw something
+    if (A.w == 1 && A.h == 1) {
+      return
+    }
+    A.forEach(function(lex,x,y) {
+      if (!((x+y)%2)) {
+        lex.clear()
+      }
+    })
+  }
   blit.square = function(A, lex){
   	// i.e. no transparency
   }