1 files changed, 132 insertions, 0 deletions

diff --git a/apps/plugins/sdl/progs/quake/snd_mix.c b/apps/plugins/sdl/progs/quake/snd_mix.c
new file mode 100644
index 0000000000..3f254552b9
--- /dev/null
+++ b/apps/plugins/sdl/progs/quake/snd_mix.c
@@ -0,0 +1,132 @@
+/*
+Copyright (C) 1996-1997 Id Software, Inc.
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  
+
+See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+*/
+// snd_mix.c -- portable code to mix sounds for snd_dma.c
+
+#include "quakedef.h"
+
+#define DWORD   unsigned long
+
+// why not write straight to SHM buffer?!?
+//portable_samplepair_t paintbuffer[PAINTBUFFER_SIZE];
+int16_t *paintbuffer; // stereo interleaved samples
+
+/*
+===============================================================================
+
+CHANNEL MIXING
+
+===============================================================================
+*/
+
+// in snd_mix_*
+
+void SND_PaintChannelFrom8 (int true_lvol, int true_rvol, signed char *sfx, int count);
+void SND_PaintChannelFrom16 (int true_lvol, int true_rvol, signed short *sfx, int count);
+
+void S_PaintChannels(int endtime)
+{
+    int         i;
+    int         end;
+    channel_t *ch;
+    sfxcache_t  *sc;
+    int         ltime, count;
+
+    paintbuffer = shm->buffer;
+        
+    //while (paintedtime < endtime)
+    //{
+    // if paintbuffer is smaller than DMA buffer
+        
+    end = endtime;
+    //if (endtime - paintedtime > PAINTBUFFER_SIZE)
+    //end = paintedtime + PAINTBUFFER_SIZE;
+        
+    // clear the paint buffer
+    memset(paintbuffer, 0, (end - paintedtime) * sizeof(int16_t));
+
+    // 0-255
+    int volume_fp = volume.value * 255;
+    
+    // paint in the channels.
+    ch = channels;
+    for (i=0; i<total_channels ; i++, ch++)
+    {
+        if (!ch->sfx)
+            continue;
+        if (!ch->leftvol && !ch->rightvol)
+            continue;
+        sc = S_LoadSound (ch->sfx); // sound fx cache
+        if (!sc)
+            continue;
+
+        ltime = paintedtime;
+
+        while (ltime < end)
+        {       // paint up to end of sound channel, or end of buffer, whichever is greatest
+            if (ch->end < end)
+                count = ch->end - ltime;
+            else
+                count = end - ltime;
+
+            //if(count == 1)
+            //    rb->splashf(HZ, "Potential problem");
+            
+            if (count > 0)
+            {
+                int true_lvol, true_rvol;
+                true_lvol = (volume_fp * ch->leftvol) / 256;
+                true_rvol = (volume_fp * ch->rightvol) / 256;
+
+                if (sc->width == 1)
+                {
+                    signed char *sfx = (char*)sc->data + ch->pos;
+                    SND_PaintChannelFrom8(true_lvol, true_rvol, sfx, count);
+                }
+                else
+                {
+                    signed short *sfx = (short*)sc->data + ch->pos;
+                    SND_PaintChannelFrom16(true_lvol, true_rvol, sfx, count);
+                }
+
+                ch->pos += count;
+                ltime += count;
+            }
+
+            // if at end of loop, restart
+            if (ltime >= ch->end)
+            {
+                if (sc->loopstart >= 0)
+                {
+                    ch->pos = sc->loopstart;
+                    ch->end = ltime + sc->length - ch->pos;
+                }
+                else                            
+                {       // channel just stopped
+                    ch->sfx = NULL;
+                    break;
+                }
+            }
+        }
+    }
+
+    // transfer out according to DMA format
+    //S_TransferPaintBuffer(end);
+    paintedtime = end;
+}