Use ACN ordering for ambisonics coefficients arrays

Note that it still uses FuMa scalings internally. Coefficients loaded from
config files specify if they're FuMa (in both ordering and scaling) or N3D,
and will get reordered or rescaled as needed.

1 files changed, 8 insertions, 4 deletions

diff --git a/Alc/ALu.c b/Alc/ALu.c
index 822189f8..14b4d134 100644
--- a/Alc/ALu.c
+++ b/Alc/ALu.c
@@ -492,6 +492,7 @@ ALvoid CalcNonAttnSourceParams(ALvoice *voice, const ALsource *ALSource, const A
     {
         ALfloat N[3], V[3], U[3];
         aluMatrix matrix;
+        ALfloat scale;
 
         /* AT then UP */
         N[0] = ALSource->Orientation[0][0];
@@ -512,11 +513,14 @@ ALvoid CalcNonAttnSourceParams(ALvoice *voice, const ALsource *ALSource, const A
         aluCrossproduct(N, V, U);
         aluNormalize(U);
 
+        /* Build a rotate + channel reorder matrix (B-Format -> ACN), and
+         * include scaling for first-order content. */
+        scale = Device->AmbiScale;
         aluMatrixSet(&matrix,
-            1.0f,  0.0f,  0.0f,  0.0f,
-            0.0f, -N[2], -N[0],  N[1],
-            0.0f,  U[2],  U[0], -U[1],
-            0.0f, -V[2], -V[0],  V[1]
+            1.0f,        0.0f,        0.0f,        0.0f,
+            0.0f, -N[0]*scale,  N[1]*scale, -N[2]*scale,
+            0.0f,  U[0]*scale, -U[1]*scale,  U[2]*scale,
+            0.0f, -V[0]*scale,  V[1]*scale, -V[2]*scale
         );
 
         for(c = 0;c < num_channels;c++)