1 files changed, 18 insertions, 0 deletions
diff --git a/OpenAL32/Include/alu.h b/OpenAL32/Include/alu.h
index 62350c3f..978527e5 100644
--- a/OpenAL32/Include/alu.h
+++ b/OpenAL32/Include/alu.h
@@ -5,6 +5,7 @@
 #include "AL/alc.h"
 #include "AL/alext.h"
 
+#include <math.h>
 #ifdef HAVE_FLOAT_H
 #include <float.h>
 #endif
@@ -46,6 +47,9 @@
 #define __min min
 #endif
 
+#define QUADRANT_NUM  128
+#define LUT_NUM       (4 * QUADRANT_NUM)
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -145,6 +149,20 @@ static __inline ALuint aluChannelsFromFormat(ALenum format)
     }
 }
 
+static __inline ALint aluCart2LUTpos(ALfloat re, ALfloat im)
+{
+    ALint pos = 0;
+    ALfloat denom = aluFabs(re) + aluFabs(im);
+    if(denom > 0.0f)
+        pos = (ALint)(QUADRANT_NUM*aluFabs(im) / denom + 0.5);
+
+    if(re < 0.0)
+        pos = 2 * QUADRANT_NUM - pos;
+    if(im < 0.0)
+        pos = LUT_NUM - pos;
+    return pos%LUT_NUM;
+}
+
 ALvoid aluInitPanning(ALCcontext *Context);
 ALvoid aluMixData(ALCdevice *device, ALvoid *buffer, ALsizei size);
 ALvoid aluHandleDisconnect(ALCdevice *device);