I'm kind of sad and scared right now

2 files changed, 39 insertions, 24 deletions

diff --git a/examples/spatial.c b/examples/spatial.c
index 9985ffe..016eeee 100644
--- a/examples/spatial.c
+++ b/examples/spatial.c
@@ -69,8 +69,8 @@ int main(int argc, char **argv) {
                        *wave;
 
     synth_sine sine_channels[2] = {
-        { SYNTH_STATUS_ON, 0.0f, 220 },
-        { SYNTH_STATUS_ON, 0.0f, 420 },
+        { SYNTH_STATUS_ON, 0.0f, 2600 },
+        { SYNTH_STATUS_ON, 0.0f,  420 },
     };
 
     xas_audio_format format = {
@@ -118,7 +118,7 @@ int main(int argc, char **argv) {
     }
 
     if (xas_spatial_scene_add_object(scene,
-                                       (xas_spatial_coord){ 0.0, 0.0, 20.0 },
+                                       (xas_spatial_coord){ 0.0, 0.0, 1.0 },
                                        synth) == NULL) {
         goto error_spatial_scene_add_object;
     }
diff --git a/src/spatial.c b/src/spatial.c
index 18173aa..710726f 100644
--- a/src/spatial.c
+++ b/src/spatial.c
@@ -1,3 +1,4 @@
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>
@@ -35,10 +36,8 @@ error_realloc_buffer:
     return -1;
 }
 
-static inline size_t sample_index(xas_spatial_scene *scene, float distance) {
-    size_t index = floorf(distance / scene->speed / scene->format.sample_rate);
-
-    return (scene->buffer->index + index) % scene->buffer->size;
+static inline size_t sample_delta(xas_spatial_scene *scene, float distance) {
+    return floorf(distance / scene->speed / scene->format.sample_rate);
 }
 
 static inline int16_t sample_scale(int16_t value, float distance) {
@@ -46,7 +45,7 @@ static inline int16_t sample_scale(int16_t value, float distance) {
 }
 
 static void buffer_zero(xas_spatial_buffer *buffer, size_t count) {
-    int16_t *dest = (int16_t *)buffer + 1;
+    int16_t *dest = (int16_t *)(buffer + 1);
     size_t i = buffer->index;
 
     if (count > buffer->size) {
@@ -58,8 +57,8 @@ static void buffer_zero(xas_spatial_buffer *buffer, size_t count) {
             i = 0;
         }
 
-        dest[i*XAS_AUDIO_STEREO]   = 0;
-        dest[i*XAS_AUDIO_STEREO+1] = 0;
+        dest[XAS_AUDIO_STEREO*i]   = 0;
+        dest[XAS_AUDIO_STEREO*i+1] = 0;
 
         i++;
     }
@@ -68,20 +67,22 @@ static void buffer_zero(xas_spatial_buffer *buffer, size_t count) {
 static void buffer_copy(xas_spatial_buffer *buffer,
                         int16_t *dest,
                         size_t count) {
-    int16_t *src = (int16_t *)buffer + 1;
-    size_t i = buffer->index;
+    int16_t *src = (int16_t *)(buffer + 1);
+
+    size_t index_i = buffer->index,
+           index_o;
 
     if (count > buffer->size) {
         count = buffer->size;
     }
 
-    while (count--) {
-        if (i == buffer->size) {
-            i = 0;
+    for (index_o=0; index_o<count; index_o++) {
+        if (index_i == buffer->size) {
+            index_i = 0;
         }
 
-        dest[i*XAS_AUDIO_STEREO]   = src[i*XAS_AUDIO_STEREO];
-        dest[i*XAS_AUDIO_STEREO+1] = src[i*XAS_AUDIO_STEREO+1];
+        dest[XAS_AUDIO_STEREO*index_o]   = src[XAS_AUDIO_STEREO*index_i];
+        dest[XAS_AUDIO_STEREO*index_o+1] = src[XAS_AUDIO_STEREO*index_i+1];
     }
 }
 
@@ -104,14 +105,14 @@ ssize_t scene_fill(xas_spatial_scene *scene,
         float distance_l = dist(scene->speaker_l, obj->coord),
               distance_r = dist(scene->speaker_r, obj->coord);
 
-        size_t index_l,
-               index_r;
+        size_t delta_l,
+               delta_r;
 
         ssize_t readlen,
                 i;
 
         if (distance_l > scene->radius || distance_r > scene->radius) {
-            continue;
+            goto next;
         }
 
         if ((readlen = xas_audio_stream_read(obj->source,
@@ -124,29 +125,42 @@ ssize_t scene_fill(xas_spatial_scene *scene,
             readlen = buffer->size;
         }
 
-        index_l = sample_index(scene, distance_l);
-        index_r = sample_index(scene, distance_r);
+        delta_l = sample_delta(scene, distance_l);
+        delta_r = sample_delta(scene, distance_r);
 
         for (i=0; i<readlen; i++) {
             int16_t value_l = sample_scale(src[i], distance_l),
                     value_r = sample_scale(src[i], distance_r);
 
+            size_t index_l,
+                   index_r;
+
             if (buffer->index == buffer->size) {
                 buffer->index = 0;
             }
 
-            dest[XAS_AUDIO_STEREO*index_l+i]   += value_l;
-            dest[XAS_AUDIO_STEREO*index_r+i+1] += value_r;
+            index_l = buffer->index + delta_l;
+            index_r = buffer->index + delta_r;
+
+            dest[XAS_AUDIO_STEREO*index_l]   += value_l;
+            dest[XAS_AUDIO_STEREO*index_r+1] += value_r;
 
             buffer->index++;
         }
 
+next:
         buffer->index = index_old;
         obj           = obj->next;
     }
 
     buffer_copy(buffer, output, count);
 
+    buffer->index += count;
+
+    if (buffer->index == buffer->size) {
+        buffer->index = 0;
+    }
+
     return count;
 
 error_audio_stream_read:
@@ -167,6 +181,7 @@ xas_spatial_scene *xas_spatial_scene_new(xas_audio_format format,
     scene->format    = format;
     scene->speaker_l = speaker_l;
     scene->speaker_r = speaker_r;
+    scene->radius    = XAS_SPATIAL_DEFAULT_RADIUS;
     scene->speed     = XAS_SPATIAL_DEFAULT_SPEED;
 
     if (buffer_realloc(scene, NULL) < 0) {