Add the Echo effect

3 files changed, 60 insertions, 0 deletions

diff --git a/OpenAL32/Include/alAuxEffectSlot.h b/OpenAL32/Include/alAuxEffectSlot.h
index a818bb47..8dfa9418 100644
--- a/OpenAL32/Include/alAuxEffectSlot.h
+++ b/OpenAL32/Include/alAuxEffectSlot.h
@@ -5,6 +5,7 @@
 #include "alEffect.h"
 #include "alFilter.h"
 #include "alReverb.h"
+#include "alEcho.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -24,6 +25,7 @@ typedef struct ALeffectslot
     ALboolean AuxSendAuto;
 
     ALverbState *ReverbState;
+    ALechoState *EchoState;
 
     ALfloat WetBuffer[BUFFERSIZE];
 
diff --git a/OpenAL32/Include/alEcho.h b/OpenAL32/Include/alEcho.h
new file mode 100644
index 00000000..34896ea7
--- /dev/null
+++ b/OpenAL32/Include/alEcho.h
@@ -0,0 +1,24 @@
+#ifndef AL_ECHO_H
+#define AL_ECHO_H
+
+#include "AL/al.h"
+#include "AL/alc.h"
+#include "alMain.h"
+#include "alEffect.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct ALechoState ALechoState;
+
+ALechoState *EchoCreate(ALCcontext *Context);
+ALvoid EchoDestroy(ALechoState *State);
+ALvoid EchoUpdate(ALCcontext *Context, struct ALeffectslot *Slot, ALeffect *Effect);
+ALvoid EchoProcess(ALechoState *State, ALuint SamplesToDo, const ALfloat *SamplesIn, ALfloat (*SamplesOut)[OUTPUTCHANNELS]);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/OpenAL32/Include/alEffect.h b/OpenAL32/Include/alEffect.h
index 5f6723bc..6dd1b766 100644
--- a/OpenAL32/Include/alEffect.h
+++ b/OpenAL32/Include/alEffect.h
@@ -37,9 +37,33 @@ extern "C" {
 #define AL_REVERB_ROOM_ROLLOFF_FACTOR                      0x000C
 #define AL_REVERB_DECAY_HFLIMIT                            0x000D
 
+#define AL_ECHO_DELAY                                      0x0001
+#define AL_ECHO_LRDELAY                                    0x0002
+#define AL_ECHO_DAMPING                                    0x0003
+#define AL_ECHO_FEEDBACK                                   0x0004
+#define AL_ECHO_SPREAD                                     0x0005
+
+#define AL_ECHO_MIN_DELAY                                  (0.0f)
+#define AL_ECHO_MAX_DELAY                                  (0.207f)
+#define AL_ECHO_DEFAULT_DELAY                              (0.1f)
+#define AL_ECHO_MIN_LRDELAY                                (0.0f)
+#define AL_ECHO_MAX_LRDELAY                                (0.404f)
+#define AL_ECHO_DEFAULT_LRDELAY                            (0.1f)
+#define AL_ECHO_MIN_DAMPING                                (0.0f)
+#define AL_ECHO_MAX_DAMPING                                (0.99f)
+#define AL_ECHO_DEFAULT_DAMPING                            (0.5f)
+#define AL_ECHO_MIN_FEEDBACK                               (0.0f)
+#define AL_ECHO_MAX_FEEDBACK                               (1.0f)
+#define AL_ECHO_DEFAULT_FEEDBACK                           (0.5f)
+#define AL_ECHO_MIN_SPREAD                                 (-1.0f)
+#define AL_ECHO_MAX_SPREAD                                 (1.0f)
+#define AL_ECHO_DEFAULT_SPREAD                             (-1.0f)
+
 
 enum {
     REVERB = 0,
+    ECHO,
+
     MAX_EFFECTS
 };
 extern ALboolean DisabledEffects[MAX_EFFECTS];
@@ -67,6 +91,16 @@ typedef struct ALeffect_struct
         ALboolean DecayHFLimit;
     } Reverb;
 
+    struct {
+        ALfloat Delay;
+        ALfloat LRDelay;
+
+        ALfloat Damping;
+        ALfloat Feedback;
+
+        ALfloat Spread;
+    } Echo;
+
     // Index to itself
     ALuint effect;