harris: Just increase convolution output pointer while writing to it

Instead of calculating the index for each step.

1 files changed, 2 insertions, 2 deletions

diff --git a/harris.c b/harris.c
index 1099f61..8602e0a 100644
--- a/harris.c
+++ b/harris.c
@@ -71,11 +71,11 @@ conv(GdkPixbuf *pixbuf, gint *operator, gint block_size)
 					Y += v * operator[j*block_size + i];
 				}
 			}
-			out[y * width + x] = Y/4;
+			*out++ = Y/4;
 		}
 	}
 
-	return out;
+	return out - width*height;
 }
 
 struct mat2 *