Calculate HRTF stepping params right before mixing

This means we track the current params and the target params, rather than the
target params and the stepping. This closer matches the non-HRTF mixers.

1 files changed, 17 insertions, 76 deletions

diff --git a/Alc/ALu.c b/Alc/ALu.c
index 4b1f0164..b36e2248 100644
--- a/Alc/ALu.c
+++ b/Alc/ALu.c
@@ -287,42 +287,6 @@ static ALboolean BsincPrepare(const ALuint increment, BsincState *state)
 }
 
 
-/* Calculates the fade time from the changes in gain and listener to source
- * angle between updates. The result is a the time, in seconds, for the
- * transition to complete.
- */
-static ALfloat CalcFadeTime(ALfloat oldGain, ALfloat newGain, const aluVector *olddir, const aluVector *newdir)
-{
-    ALfloat gainChange, angleChange, change;
-
-    /* Calculate the normalized dB gain change. */
-    newGain = maxf(newGain, 0.0001f);
-    oldGain = maxf(oldGain, 0.0001f);
-    gainChange = fabsf(log10f(newGain / oldGain) / log10f(0.0001f));
-
-    /* Calculate the angle change only when there is enough gain to notice it. */
-    angleChange = 0.0f;
-    if(gainChange > 0.0001f || newGain > 0.0001f)
-    {
-        /* No angle change when the directions are equal or degenerate (when
-         * both have zero length).
-         */
-        if(newdir->v[0] != olddir->v[0] || newdir->v[1] != olddir->v[1] || newdir->v[2] != olddir->v[2])
-        {
-            ALfloat dotp = aluDotproduct(olddir, newdir);
-            angleChange = acosf(clampf(dotp, -1.0f, 1.0f)) / F_PI;
-        }
-    }
-
-    /* Use the largest of the two changes, and apply a significance shaping
-     * function to it. The result is then scaled to cover a 15ms transition
-     * range.
-     */
-    change = maxf(angleChange * 25.0f, gainChange) * 2.0f;
-    return minf(change, 1.0f) * 0.015f;
-}
-
-
 static ALvoid CalcListenerParams(ALlistener *Listener)
 {
     ALdouble N[3], V[3], U[3], P[3];
@@ -684,12 +648,12 @@ ALvoid CalcNonAttnSourceParams(ALvoice *voice, const ALsource *ALSource, const A
                 if(chans[c].channel == LFE)
                 {
                     /* Skip LFE */
-                    voice->Direct.Hrtf[c].Params.Delay[0] = 0;
-                    voice->Direct.Hrtf[c].Params.Delay[1] = 0;
+                    voice->Direct.Hrtf[c].Target.Delay[0] = 0;
+                    voice->Direct.Hrtf[c].Target.Delay[1] = 0;
                     for(i = 0;i < HRIR_LENGTH;i++)
                     {
-                        voice->Direct.Hrtf[c].Params.Coeffs[i][0] = 0.0f;
-                        voice->Direct.Hrtf[c].Params.Coeffs[i][1] = 0.0f;
+                        voice->Direct.Hrtf[c].Target.Coeffs[i][0] = 0.0f;
+                        voice->Direct.Hrtf[c].Target.Coeffs[i][1] = 0.0f;
                     }
 
                     for(i = 0;i < NumSends;i++)
@@ -704,8 +668,8 @@ ALvoid CalcNonAttnSourceParams(ALvoice *voice, const ALsource *ALSource, const A
                 /* Get the static HRIR coefficients and delays for this channel. */
                 GetLerpedHrtfCoeffs(Device->Hrtf,
                     chans[c].elevation, chans[c].angle, 1.0f, DryGain,
-                    voice->Direct.Hrtf[c].Params.Coeffs,
-                    voice->Direct.Hrtf[c].Params.Delay
+                    voice->Direct.Hrtf[c].Target.Coeffs,
+                    voice->Direct.Hrtf[c].Target.Delay
                 );
 
                 /* Normal panning for auxiliary sends. */
@@ -726,7 +690,6 @@ ALvoid CalcNonAttnSourceParams(ALvoice *voice, const ALsource *ALSource, const A
                     }
                 }
             }
-            voice->Direct.HrtfCounter = 0;
 
             voice->IsHrtf = AL_TRUE;
         }
@@ -1186,37 +1149,10 @@ ALvoid CalcSourceParams(ALvoice *voice, const ALsource *ALSource, const ALCconte
                 dirfact *= 1.0f - (asinf(radius / Distance) / F_PI);
         }
 
-        /* Check to see if the HRIR is already moving. */
-        if(voice->Moving)
-        {
-            ALfloat delta;
-            delta = CalcFadeTime(voice->Direct.LastGain, DryGain,
-                                 &voice->Direct.LastDir, &dir);
-            /* If the delta is large enough, get the moving HRIR target
-             * coefficients, target delays, steppping values, and counter.
-             */
-            if(delta > 0.000015f)
-            {
-                ALuint counter = GetMovingHrtfCoeffs(Device->Hrtf,
-                    ev, az, dirfact, DryGain, delta, voice->Direct.HrtfCounter,
-                    voice->Direct.Hrtf[0].Params.Coeffs, voice->Direct.Hrtf[0].Params.Delay,
-                    voice->Direct.Hrtf[0].Params.CoeffStep, voice->Direct.Hrtf[0].Params.DelayStep
-                );
-                voice->Direct.HrtfCounter = counter;
-                voice->Direct.LastGain = DryGain;
-                voice->Direct.LastDir = dir;
-            }
-        }
-        else
-        {
-            /* Get the initial (static) HRIR coefficients and delays. */
-            GetLerpedHrtfCoeffs(Device->Hrtf, ev, az, dirfact, DryGain,
-                                voice->Direct.Hrtf[0].Params.Coeffs,
-                                voice->Direct.Hrtf[0].Params.Delay);
-            voice->Direct.HrtfCounter = 0;
-            voice->Direct.LastGain = DryGain;
-            voice->Direct.LastDir = dir;
-        }
+        /* Get the HRIR coefficients and delays. */
+        GetLerpedHrtfCoeffs(Device->Hrtf, ev, az, dirfact, DryGain,
+                            voice->Direct.Hrtf[0].Target.Coeffs,
+                            voice->Direct.Hrtf[0].Target.Delay);
 
         dir.v[0] *= dirfact;
         dir.v[1] *= dirfact;
@@ -1537,11 +1473,16 @@ ALvoid aluMixData(ALCdevice *device, ALvoid *buffer, ALsizei size)
         {
             HrtfMixerFunc HrtfMix = SelectHrtfMixer();
             ALuint irsize = GetHrtfIrSize(device->Hrtf);
+            MixHrtfParams hrtfparams;
+            memset(&hrtfparams, 0, sizeof(hrtfparams));
             for(c = 0;c < device->NumChannels;c++)
+            {
+                hrtfparams.Current = &device->Hrtf_Params[c];
+                hrtfparams.Target = &device->Hrtf_Params[c];
                 HrtfMix(OutBuffer, device->DryBuffer[c], 0, device->Hrtf_Offset,
-                    0, irsize, &device->Hrtf_Params[c], &device->Hrtf_State[c],
-                    SamplesToDo
+                    0, irsize, &hrtfparams, &device->Hrtf_State[c], SamplesToDo
                 );
+            }
             device->Hrtf_Offset += SamplesToDo;
         }
         else if(device->Bs2b)