#if !defined(_GHB_PREVIEW_H_)
#define _GHB_PREVIEW_H_
-#define MOD_ROUND(v,m) (m * ((v + (m>>1) - 1) / m))
+#define MOD_ROUND(v,m) ((m==1)?v:(m * ((v + (m>>1) - 1) / m)))
#define MOD_DOWN(v,m) (m * (v / m))
#define MOD_UP(v,m) (m * ((v + m - 1) / m))