1 files changed, 18 insertions, 0 deletions
diff --git a/Src/Wasabi/bfc/std_math.cpp b/Src/Wasabi/bfc/std_math.cpp
new file mode 100644
index 00000000..9bbfe112
--- /dev/null
+++ b/Src/Wasabi/bfc/std_math.cpp
@@ -0,0 +1,18 @@
+#include "precomp_wasabi_bfc.h"
+
+#include "std_math.h"
+
+
+void premultiplyARGB32(ARGB32 *words, int nwords) 
+{
+  for (; nwords > 0; nwords--, words++) 
+	{
+    unsigned char *pixel = (unsigned char *)words;
+    unsigned int alpha = pixel[3];
+    if (alpha == 255) continue;
+    pixel[0] = (pixel[0] * alpha) >> 8;	// blue
+    pixel[1] = (pixel[1] * alpha) >> 8;	// green
+    pixel[2] = (pixel[2] * alpha) >> 8;	// red
+  }
+}
+