Update mixing code

cli/vgmstream_cli.c

@@ -340,7 +340,7 @@ int main(int argc, char ** argv) {
     char outfilename_temp[PATH_LIMIT];
 
     sample_t * buf = NULL;
-    int channels;
+    int channels, input_channels;
     int32_t len_samples;
     int32_t fade_samples;
     int i, j;
@@ -458,8 +458,19 @@ int main(int argc, char ** argv) {
 
     /* last init */
     channels = vgmstream->channels;
+    input_channels = vgmstream->channels;
 
-    buf = malloc(BUFFER_SAMPLES * sizeof(sample_t) * channels);
+#ifdef VGMSTREAM_MIXING
+    /* enable after all config but before outbuf */
+    {
+        vgmstream_enable_mixing(vgmstream, BUFFER_SAMPLES);
+
+        channels = vgmstream->output_channels;
+        input_channels = vgmstream->input_channels;
+    }
+#endif
+
+    buf = malloc(BUFFER_SAMPLES * sizeof(sample_t) * input_channels);
     if (!buf) {
         fprintf(stderr,"failed allocating output buffer\n");
         goto fail;

src/vgmstream.c

@@ -569,6 +569,16 @@ static VGMSTREAM * init_vgmstream_internal(STREAMFILE *streamFile) {
 }
 
 void setup_vgmstream(VGMSTREAM * vgmstream) {
+
+#ifdef VGMSTREAM_MIXING
+    /* fill default config to simplify external code (mixing off will always happen
+     * initially, and if they contain values it means mixing must be enabled) */
+    if (!vgmstream->mixing_on || vgmstream->input_channels <= 0)
+        vgmstream->input_channels = vgmstream->channels;
+    if (!vgmstream->mixing_on || vgmstream->output_channels <= 0)
+        vgmstream->output_channels = vgmstream->channels;
+#endif
+
     /* save start things so we can restart when seeking */
     memcpy(vgmstream->start_ch, vgmstream->ch, sizeof(VGMSTREAMCHANNEL)*vgmstream->channels);
     memcpy(vgmstream->start_vgmstream, vgmstream, sizeof(VGMSTREAM));
@@ -747,9 +757,9 @@ VGMSTREAM * allocate_vgmstream(int channel_count, int loop_flag) {
 
 #ifdef VGMSTREAM_MIXING
     /* fixed arrays, for now */
-    vgmstream->mixing_size = 64;
-    vgmstream->stream_name_size = STREAM_NAME_SIZE;
+    vgmstream->mixing_size = VGMSTREAM_MAX_MIXING;
 #endif
+    //vgmstream->stream_name_size = STREAM_NAME_SIZE;
     return vgmstream;
 fail:
     if (vgmstream) {
@@ -980,6 +990,9 @@ void vgmstream_set_loop_target(VGMSTREAM* vgmstream, int loop_target) {
             vgmstream_set_loop_target(data->layers[i], loop_target);
         }
     }
+
+    /* notify of new initial state */
+    setup_vgmstream(vgmstream);
 }
 
 
@@ -1042,7 +1055,7 @@ void render_vgmstream(sample * buffer, int32_t sample_count, VGMSTREAM * vgmstre
             break;
     }
 
-
+#ifndef VGMSTREAM_MIXING
     /* swap channels if set, to create custom channel mappings */
     if (vgmstream->channel_mappings_on) {
         int ch_from,ch_to,s;
@@ -1075,6 +1088,11 @@ void render_vgmstream(sample * buffer, int32_t sample_count, VGMSTREAM * vgmstre
             }
         }
     }
+#endif
+
+#ifdef VGMSTREAM_MIXING
+    mix_vgmstream(buffer, sample_count, vgmstream);
+#endif
 }
 
 /* Get the number of samples of a single frame (smallest self-contained sample group, 1/N channels) */
@@ -2529,7 +2547,7 @@ static void try_dual_file_stereo(VGMSTREAM * opened_vgmstream, STREAMFILE *strea
     }
 
     /* check these even if there is no loop, because they should then be zero in both
-     * Homura PS2 right channel doesn't have loop points so it's ignored */
+     * (Homura PS2 right channel doesn't have loop points so this check is ignored) */
     if (new_vgmstream->meta_type != meta_PS2_SMPL &&
             !(new_vgmstream->loop_flag      == opened_vgmstream->loop_flag &&
             new_vgmstream->loop_start_sample== opened_vgmstream->loop_start_sample &&

src/vgmstream.h

@@ -9,6 +9,9 @@
 enum { PATH_LIMIT = 32768 };
 enum { STREAM_NAME_SIZE = 255 };
 enum { VGMSTREAM_MAX_CHANNELS = 64 };
+#ifdef VGMSTREAM_MIXING
+enum { VGMSTREAM_MAX_MIXING = 64 };
+#endif
 
 #include "streamfile.h"
 
@@ -731,20 +734,28 @@ typedef enum {
     MIX_ADD,
     MIX_ADD_VOLUME,
     MIX_VOLUME,
-    MIX_CROSSFADE,
+    MIX_LIMIT,
     MIX_DOWNMIX,
     MIX_DOWNMIX_REST,
-    MIX_UPMIX
+    MIX_UPMIX,
+    MIX_FADE
 } mix_command_t;
 
 typedef struct {
     mix_command_t command;
-    int ch_a;
-    int ch_b;
-    float vol_a;
-    float vol_b;
-    float pos_a;
-    float pos_b;
+    /* common */
+    int ch_dst;
+    int ch_src;
+    float vol;
+
+    /* fade envelope */
+    float vol_start;    /* volume from pre to start */
+    float vol_end;      /* volume from end to post */
+    char shape;         /* curve type */
+    float time_pre;     /* position before curve where vol_str applies (-1 = beginning) */
+    float time_start;   /* curve start position where vol changes from src to dst */
+    float time_end;     /* curve end position where vol changes from src to dst */
+    float time_post;    /* position after curve where vol_dst applies (-1 = end) */
 } mix_config_data;
 #endif
 
@@ -823,15 +834,19 @@ typedef struct {
 
     /* other config */
     int allow_dual_stereo;          /* search for dual stereo (file_L.ext + file_R.ext = single stereo file) */
+#ifndef VGMSTREAM_MIXING
     uint32_t channel_mask;          /* to silence crossfading subsongs/layers */
     int channel_mappings_on;        /* channel mappings are active */
     int channel_mappings[32];       /* swap channel "i" with "[i]" */
+#endif
 #ifdef VGMSTREAM_MIXING
-    int output_channels;            /* resulting channels after mixing (may be ignored if plugin doesn't support it) */
+    /* may be ignored if plugin doesn't support it, but fields will be always set to simplify plugin's code */
+    int input_channels;             /* starting channels before mixing (outbuf must be this big) */
+    int output_channels;            /* resulting channels after mixing */
     int mixing_on;                  /* mixing allowed */
     int mixing_count;               /* mixing number */
-    mix_config_data mixing[64];     /* applies transformation to output samples (could be alloc'ed but to simplify...) */
     size_t mixing_size;             /* mixing max */
+    mix_config_data mixing_chain[VGMSTREAM_MAX_MIXING]; /* effects to apply (could be alloc'ed but to simplify...) */
 #endif
     /* config requests, players must read and honor these values */
     /* (ideally internally would work as a player, but for now player must do it manually) */
@@ -1317,6 +1332,15 @@ VGMSTREAM * allocate_vgmstream(int channel_count, int looped);
 /* Prepare the VGMSTREAM's initial state once parsed and ready, but before playing. */
 void setup_vgmstream(VGMSTREAM * vgmstream);
 
+#ifdef VGMSTREAM_MIXING
+/* Applies mixing commands to the vgmstream to the sample buffer.
+ * Mixing must be enabled and outbuf must be big enough for output_channels*samples_to_do big. */
+void mix_vgmstream(sample_t *outbuf, int32_t sample_count, VGMSTREAM* vgmstream);
+
+/* Add a new internal mix. Always use this as it validates mixes. */
+void vgmstream_add_mixing(VGMSTREAM* vgmstream, mix_config_data mix);
+#endif
+
 /* Get the number of samples of a single frame (smallest self-contained sample group, 1/N channels) */
 int get_vgmstream_samples_per_frame(VGMSTREAM * vgmstream);
 /* Get the number of bytes of a single frame (smallest self-contained byte group, 1/N channels) */