Use ALfilterState for the source direct and send filters

1 files changed, 11 insertions, 0 deletions

diff --git a/OpenAL32/alFilter.c b/OpenAL32/alFilter.c
index 5bef87fd..550c99f5 100644
--- a/OpenAL32/alFilter.c
+++ b/OpenAL32/alFilter.c
@@ -343,6 +343,17 @@ void ALfilterState_setParams(ALfilterState *filter, ALfilterType type, ALfloat g
     /* Calculate filter coefficients depending on filter type */
     switch(type)
     {
+        case ALfilterType_LowPass:
+            alpha = sinf(w0) / 2.0f * sqrtf((gain + 1.0f/gain) *
+                                            (1.0f/0.75f - 1.0f) + 2.0f);
+            filter->b[0] = (1.0f - cosf(w0)) * 0.5f;
+            filter->b[1] =  1.0f - cosf(w0);
+            filter->b[2] = (1.0f - cosf(w0)) * 0.5f;
+            filter->a[0] =  1.0f + alpha;
+            filter->a[1] = -2.0f*cosf(w0);
+            filter->a[2] =  1.0f - alpha;
+            break;
+
         case ALfilterType_HighShelf:
             alpha = sinf(w0) / 2.0f * sqrtf((gain + 1.0f/gain) *
                                             (1.0f/0.75f - 1.0f) + 2.0f);