Be context-agnostic in the effect Create functions

This allows the effect Update functions to handle the playback frequency being
changed. By default the effects assume a maximum frequency of 192khz, however,
it can go higher at the cost of the sample buffers being cleared and the risk
of an abort() if reallocation fails

2 files changed, 164 insertions, 89 deletions

diff --git a/Alc/alcEcho.c b/Alc/alcEcho.c
index deaae622..8aa4d2ce 100644
--- a/Alc/alcEcho.c
+++ b/Alc/alcEcho.c
@@ -29,6 +29,10 @@
 #include "alError.h"
 #include "alu.h"
 
+// Just a soft maximum. Being higher will cause EchoUpdate to reallocate the
+// sample buffer which may cause an abort if realloc fails
+#define MAX_ECHO_FREQ  192000
+
 typedef struct ALechoState {
     // Must be first in all effects!
     ALeffectState state;
@@ -36,11 +40,12 @@ typedef struct ALechoState {
     ALfloat *SampleBuffer;
     ALuint BufferLength;
 
-    // The echo is two tap. The third tap is the offset to write the feedback
-    // and input sample to
+    // The echo is two tap. The delay is the number of samples from before the
+    // current offset
     struct {
-        ALuint offset;
-    } Tap[3];
+        ALuint delay;
+    } Tap[2];
+    ALuint Offset;
     // The LR gains for the first tap. The second tap uses the reverse
     ALfloat GainL;
     ALfloat GainR;
@@ -80,19 +85,35 @@ ALvoid EchoDestroy(ALeffectState *effect)
     }
 }
 
-ALvoid EchoUpdate(ALeffectState *effect, ALCcontext *Context, ALeffect *Effect)
+ALvoid EchoUpdate(ALeffectState *effect, ALCcontext *Context, const ALeffect *Effect)
 {
     ALechoState *state = (ALechoState*)effect;
-    ALuint newdelay1, newdelay2;
     ALfloat lrpan, cw, a, g;
+    ALuint maxlen;
 
-    newdelay1 = (ALuint)(Effect->Echo.Delay * Context->Frequency);
-    newdelay2 = (ALuint)(Effect->Echo.LRDelay * Context->Frequency);
+    maxlen  = (ALuint)(AL_ECHO_MAX_DELAY * Context->Frequency);
+    maxlen += (ALuint)(AL_ECHO_MAX_LRDELAY * Context->Frequency);
+    maxlen  = NextPowerOf2(maxlen+1);
+
+    if(maxlen > state->BufferLength)
+    {
+        void *temp;
+        ALuint i;
+
+        state->BufferLength = maxlen;
+        temp = realloc(state->SampleBuffer, state->BufferLength * sizeof(ALfloat));
+        if(!temp)
+        {
+            AL_PRINT("Failed reallocation!");
+            abort();
+        }
+        for(i = 0;i < state->BufferLength;i++)
+            state->SampleBuffer[i] = 0.0f;
+    }
 
-    state->Tap[0].offset = (state->BufferLength - newdelay1 - 1 +
-                            state->Tap[2].offset)%state->BufferLength;
-    state->Tap[1].offset = (state->BufferLength - newdelay1 - newdelay2 - 1 +
-                            state->Tap[2].offset)%state->BufferLength;
+    state->Tap[0].delay = (ALuint)(Effect->Echo.Delay * Context->Frequency);
+    state->Tap[1].delay = (ALuint)(Effect->Echo.LRDelay * Context->Frequency);
+    state->Tap[1].delay += state->Tap[0].delay;
 
     lrpan = Effect->Echo.Spread*0.5f + 0.5f;
     state->GainL = aluSqrt(     lrpan);
@@ -111,32 +132,30 @@ ALvoid EchoUpdate(ALeffectState *effect, ALCcontext *Context, ALeffect *Effect)
 ALvoid EchoProcess(ALeffectState *effect, const ALeffectslot *Slot, ALuint SamplesToDo, const ALfloat *SamplesIn, ALfloat (*SamplesOut)[OUTPUTCHANNELS])
 {
     ALechoState *state = (ALechoState*)effect;
-    const ALuint delay = state->BufferLength-1;
-    ALuint tap1off = state->Tap[0].offset;
-    ALuint tap2off = state->Tap[1].offset;
-    ALuint fboff = state->Tap[2].offset;
-    ALfloat gain = Slot->Gain;
-    ALfloat samp[2];
+    const ALuint mask = state->BufferLength-1;
+    const ALuint tap1 = state->Tap[0].delay;
+    const ALuint tap2 = state->Tap[1].delay;
+    ALuint offset = state->Offset;
+    const ALfloat gain = Slot->Gain;
+    ALfloat samp[2], smp;
     ALuint i;
 
-    for(i = 0;i < SamplesToDo;i++)
+    for(i = 0;i < SamplesToDo;i++,offset++)
     {
-        // Apply damping
-        samp[0] = lpFilter2P(&state->iirFilter, 0, state->SampleBuffer[tap2off]+SamplesIn[i]);
-
-        // Apply feedback gain and mix in the new sample
-        state->SampleBuffer[fboff] = samp[0] * state->FeedGain;
-
-        tap1off = (tap1off+1) & delay;
-        tap2off = (tap2off+1) & delay;
-        fboff = (fboff+1) & delay;
-
         // Sample first tap
-        samp[0] = state->SampleBuffer[tap1off]*state->GainL;
-        samp[1] = state->SampleBuffer[tap1off]*state->GainR;
+        smp = state->SampleBuffer[(offset-tap1) & mask];
+        samp[0] = smp * state->GainL;
+        samp[1] = smp * state->GainR;
         // Sample second tap. Reverse LR panning
-        samp[0] += state->SampleBuffer[tap2off]*state->GainR;
-        samp[1] += state->SampleBuffer[tap2off]*state->GainL;
+        smp = state->SampleBuffer[(offset-tap2) & mask];
+        samp[0] += smp * state->GainR;
+        samp[1] += smp * state->GainL;
+
+        // Apply damping and feedback gain to the second tap, and mix in the
+        // new sample
+        smp = lpFilter2P(&state->iirFilter, 0, smp+SamplesIn[i]);
+        state->SampleBuffer[offset&mask] = smp * state->FeedGain;
+
         // Apply slot gain
         samp[0] *= gain;
         samp[1] *= gain;
@@ -148,13 +167,10 @@ ALvoid EchoProcess(ALeffectState *effect, const ALeffectslot *Slot, ALuint Sampl
         SamplesOut[i][BACK_LEFT]   += samp[0];
         SamplesOut[i][BACK_RIGHT]  += samp[1];
     }
-
-    state->Tap[0].offset = tap1off;
-    state->Tap[1].offset = tap2off;
-    state->Tap[2].offset = fboff;
+    state->Offset = offset;
 }
 
-ALeffectState *EchoCreate(ALCcontext *Context)
+ALeffectState *EchoCreate(void)
 {
     ALechoState *state;
     ALuint i, maxlen;
@@ -170,8 +186,8 @@ ALeffectState *EchoCreate(ALCcontext *Context)
     state->state.Update = EchoUpdate;
     state->state.Process = EchoProcess;
 
-    maxlen  = (ALuint)(AL_ECHO_MAX_DELAY * Context->Frequency);
-    maxlen += (ALuint)(AL_ECHO_MAX_LRDELAY * Context->Frequency);
+    maxlen  = (ALuint)(AL_ECHO_MAX_DELAY * MAX_ECHO_FREQ);
+    maxlen += (ALuint)(AL_ECHO_MAX_LRDELAY * MAX_ECHO_FREQ);
 
     // Use the next power of 2 for the buffer length, so the tap offsets can be
     // wrapped using a mask instead of a modulo
@@ -187,9 +203,9 @@ ALeffectState *EchoCreate(ALCcontext *Context)
     for(i = 0;i < state->BufferLength;i++)
         state->SampleBuffer[i] = 0.0f;
 
-    state->Tap[0].offset = 0;
-    state->Tap[1].offset = 0;
-    state->Tap[2].offset = 0;
+    state->Tap[0].delay = 0;
+    state->Tap[1].delay = 0;
+    state->Offset = 0;
     state->GainL = 0.0f;
     state->GainR = 0.0f;
 
diff --git a/Alc/alcReverb.c b/Alc/alcReverb.c
index 42c823ce..f0d9e0be 100644
--- a/Alc/alcReverb.c
+++ b/Alc/alcReverb.c
@@ -31,6 +31,10 @@
 #include "alError.h"
 #include "alu.h"
 
+// Just a soft maximum. Being higher will cause VerbUpdate to reallocate the
+// sample buffer which may cause an abort if realloc fails
+#define MAX_REVERB_FREQ  192000
+
 typedef struct DelayLine
 {
     // The delay lines use sample lengths that are powers of 2 to allow
@@ -46,6 +50,7 @@ typedef struct ALverbState {
     // All delay lines are allocated as a single buffer to reduce memory
     // fragmentation and management code.
     ALfloat  *SampleBuffer;
+    ALuint    TotalLength;
     // Master effect low-pass filter (2 chained 1-pole filters).
     FILTER    LpFilter;
     ALfloat   LpHistory[2];
@@ -143,6 +148,46 @@ static ALuint NextPowerOf2(ALuint value)
     return powerOf2;
 }
 
+static ALuint CalcLengths(ALuint length[13], ALuint frequency)
+{
+    ALuint samples, totalLength, index;
+
+    // All line lengths are powers of 2, calculated from their lengths, with
+    // an additional sample in case of rounding errors.
+
+    // See VerbUpdate() for an explanation of the additional calculation
+    // added to the master line length.
+    samples = (ALuint)
+              ((MASTER_LINE_LENGTH +
+                (LATE_LINE_LENGTH[0] * (1.0f + LATE_LINE_MULTIPLIER) *
+                 (DECO_FRACTION * ((DECO_MULTIPLIER * DECO_MULTIPLIER *
+                                    DECO_MULTIPLIER) - 1.0f)))) *
+               frequency) + 1;
+    length[0] = NextPowerOf2(samples);
+    totalLength = length[0];
+    for(index = 0;index < 4;index++)
+    {
+        samples = (ALuint)(EARLY_LINE_LENGTH[index] * frequency) + 1;
+        length[1 + index] = NextPowerOf2(samples);
+        totalLength += length[1 + index];
+    }
+    for(index = 0;index < 4;index++)
+    {
+        samples = (ALuint)(ALLPASS_LINE_LENGTH[index] * frequency) + 1;
+        length[5 + index] = NextPowerOf2(samples);
+        totalLength += length[5 + index];
+    }
+    for(index = 0;index < 4;index++)
+    {
+        samples = (ALuint)(LATE_LINE_LENGTH[index] *
+                           (1.0f + LATE_LINE_MULTIPLIER) * frequency) + 1;
+        length[9 + index] = NextPowerOf2(samples);
+        totalLength += length[9 + index];
+    }
+
+    return totalLength;
+}
+
 // Basic delay line input/output routines.
 static __inline ALfloat DelayLineOut(DelayLine *Delay, ALuint offset)
 {
@@ -369,12 +414,62 @@ static __inline ALint aluCart2LUTpos(ALfloat re, ALfloat im)
 
 // This updates the reverb state.  This is called any time the reverb effect
 // is loaded into a slot.
-ALvoid VerbUpdate(ALeffectState *effect, ALCcontext *Context, ALeffect *Effect)
+ALvoid VerbUpdate(ALeffectState *effect, ALCcontext *Context, const ALeffect *Effect)
 {
     ALverbState *State = (ALverbState*)effect;
     ALuint index;
     ALfloat length, mixCoeff, cw, g, coeff;
     ALfloat hfRatio = Effect->Reverb.DecayHFRatio;
+    ALuint lengths[13], totalLength;
+
+    totalLength = CalcLengths(lengths, Context->Frequency);
+    if(totalLength > State->TotalLength)
+    {
+        void *temp;
+
+        State->TotalLength = totalLength;
+        temp = realloc(State->SampleBuffer, State->TotalLength * sizeof(ALfloat));
+        if(!temp)
+        {
+            AL_PRINT("Failed reallocation!");
+            abort();
+        }
+        State->SampleBuffer = temp;
+
+        for(index = 0; index < totalLength;index++)
+            State->SampleBuffer[index] = 0.0f;
+
+        // All lines share a single sample buffer
+        State->Delay.Mask = lengths[0] - 1;
+        State->Delay.Line = &State->SampleBuffer[0];
+        totalLength = lengths[0];
+        for(index = 0;index < 4;index++)
+        {
+            State->Early.Delay[index].Mask = lengths[1 + index] - 1;
+            State->Early.Delay[index].Line = &State->SampleBuffer[totalLength];
+            totalLength += lengths[1 + index];
+        }
+        for(index = 0;index < 4;index++)
+        {
+            State->Late.ApDelay[index].Mask = lengths[5 + index] - 1;
+            State->Late.ApDelay[index].Line = &State->SampleBuffer[totalLength];
+            totalLength += lengths[5 + index];
+        }
+        for(index = 0;index < 4;index++)
+        {
+            State->Late.Delay[index].Mask = lengths[9 + index] - 1;
+            State->Late.Delay[index].Line = &State->SampleBuffer[totalLength];
+            totalLength += lengths[9 + index];
+        }
+    }
+
+    for(index = 0;index < 4;index++)
+    {
+        State->Early.Offset[index] = (ALuint)(EARLY_LINE_LENGTH[index] *
+                                              Context->Frequency);
+        State->Late.ApOffset[index] = (ALuint)(ALLPASS_LINE_LENGTH[index] *
+                                               Context->Frequency);
+    }
 
     // Calculate the master low-pass filter (from the master effect HF gain).
     cw = cos(2.0 * M_PI * Effect->Reverb.HFReference / Context->Frequency);
@@ -659,10 +754,10 @@ ALvoid EAXVerbProcess(ALeffectState *effect, const ALeffectslot *Slot, ALuint Sa
 
 // This creates the reverb state.  It should be called only when the reverb
 // effect is loaded into a slot that doesn't already have a reverb effect.
-ALeffectState *VerbCreate(ALCcontext *Context)
+ALeffectState *VerbCreate(void)
 {
     ALverbState *State = NULL;
-    ALuint samples, length[13], totalLength, index;
+    ALuint length[13], totalLength, index;
 
     State = malloc(sizeof(ALverbState));
     if(!State)
@@ -675,42 +770,10 @@ ALeffectState *VerbCreate(ALCcontext *Context)
     State->state.Update = VerbUpdate;
     State->state.Process = VerbProcess;
 
-    // All line lengths are powers of 2, calculated from their lengths, with
-    // an additional sample in case of rounding errors.
-
-    // See VerbUpdate() for an explanation of the additional calculation
-    // added to the master line length.
-    samples = (ALuint)
-              ((MASTER_LINE_LENGTH +
-                (LATE_LINE_LENGTH[0] * (1.0f + LATE_LINE_MULTIPLIER) *
-                 (DECO_FRACTION * ((DECO_MULTIPLIER * DECO_MULTIPLIER *
-                                    DECO_MULTIPLIER) - 1.0f)))) *
-               Context->Frequency) + 1;
-    length[0] = NextPowerOf2(samples);
-    totalLength = length[0];
-    for(index = 0;index < 4;index++)
-    {
-        samples = (ALuint)(EARLY_LINE_LENGTH[index] * Context->Frequency) + 1;
-        length[1 + index] = NextPowerOf2(samples);
-        totalLength += length[1 + index];
-    }
-    for(index = 0;index < 4;index++)
-    {
-        samples = (ALuint)(ALLPASS_LINE_LENGTH[index] * Context->Frequency) + 1;
-        length[5 + index] = NextPowerOf2(samples);
-        totalLength += length[5 + index];
-    }
-    for(index = 0;index < 4;index++)
-    {
-        samples = (ALuint)(LATE_LINE_LENGTH[index] *
-                           (1.0f + LATE_LINE_MULTIPLIER) * Context->Frequency) + 1;
-        length[9 + index] = NextPowerOf2(samples);
-        totalLength += length[9 + index];
-    }
+    totalLength = CalcLengths(length, MAX_REVERB_FREQ);
 
-    // All lines share a single sample buffer and have their masks and start
-    // addresses calculated once.
-    State->SampleBuffer = malloc(totalLength * sizeof(ALfloat));
+    State->TotalLength = totalLength;
+    State->SampleBuffer = malloc(State->TotalLength * sizeof(ALfloat));
     if(!State->SampleBuffer)
     {
         free(State);
@@ -741,9 +804,7 @@ ALeffectState *VerbCreate(ALCcontext *Context)
         State->Early.Delay[index].Line = &State->SampleBuffer[totalLength];
         totalLength += length[1 + index];
 
-        // The early delay lines have their read offsets calculated once.
-        State->Early.Offset[index] = (ALuint)(EARLY_LINE_LENGTH[index] *
-                                              Context->Frequency);
+        State->Early.Offset[index] = 0;
     }
 
     State->Late.Gain = 0.0f;
@@ -758,9 +819,7 @@ ALeffectState *VerbCreate(ALCcontext *Context)
         State->Late.ApDelay[index].Line = &State->SampleBuffer[totalLength];
         totalLength += length[5 + index];
 
-        // The late all-pass lines have their read offsets calculated once.
-        State->Late.ApOffset[index] = (ALuint)(ALLPASS_LINE_LENGTH[index] *
-                                               Context->Frequency);
+        State->Late.ApOffset[index] = 0;
     }
 
     for(index = 0;index < 4;index++)
@@ -787,9 +846,9 @@ ALeffectState *VerbCreate(ALCcontext *Context)
     return &State->state;
 }
 
-ALeffectState *EAXVerbCreate(ALCcontext *Context)
+ALeffectState *EAXVerbCreate(void)
 {
-    ALeffectState *State = VerbCreate(Context);
+    ALeffectState *State = VerbCreate();
     if(State) State->Process = EAXVerbProcess;
     return State;
 }