1 files changed, 86 insertions, 0 deletions
diff --git a/backends/dc/audio.cpp b/backends/dc/audio.cpp
new file mode 100644
index 0000000000..863c1e97ac
--- /dev/null
+++ b/backends/dc/audio.cpp
@@ -0,0 +1,86 @@
+/* ScummVM - Scumm Interpreter
+ * Dreamcast port
+ * Copyright (C) 2002  Marcus Comstedt
+ *
+ * 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.
+ *
+ * $Header$
+ *
+ */
+
+#include "stdafx.h"
+#include "scumm.h"
+#include "dc.h"
+
+EXTERN_C void *memcpy4(void *s1, const void *s2, unsigned int n);
+
+void initSound()
+{
+  stop_sound();
+  do_sound_command(CMD_SET_FREQ_EXP(FREQ_22050_EXP));
+  do_sound_command(CMD_SET_BUFFER(3));
+}
+
+bool OSystem_Dreamcast::set_sound_proc(void *param, SoundProc *proc,
+				       byte format)
+{
+#if SAMPLE_MODE == 0
+  assert(format == SOUND_16BIT);
+#elif SAMPLE_MODE == 1
+  assert(format == SOUND_8BIT);
+#else
+#error Invalid SAMPLE_MODE
+#endif
+  _sound_proc_param = param;
+  _sound_proc = proc;
+
+  return true;
+}
+
+void OSystem_Dreamcast::checkSound()
+{
+  int n;
+  int curr_ring_buffer_samples;
+
+  if(read_sound_int(&SOUNDSTATUS->mode) != MODE_PLAY)
+    start_sound();
+
+  curr_ring_buffer_samples = read_sound_int(&SOUNDSTATUS->ring_length);
+
+  n = read_sound_int(&SOUNDSTATUS->samplepos);
+
+  if((n-=fillpos)<0)
+    n += curr_ring_buffer_samples;
+
+  n = ADJUST_BUFFER_SIZE(n-10);
+
+  if(n<100)
+    return;
+
+  _sound_proc(_sound_proc_param, (byte*)temp_sound_buffer,
+	      SAMPLES_TO_BYTES(n));
+
+  if(fillpos+n > curr_ring_buffer_samples) {
+    int r = curr_ring_buffer_samples - fillpos;
+    memcpy4(RING_BUF+fillpos, temp_sound_buffer, SAMPLES_TO_BYTES(r));
+    fillpos = 0;
+    n -= r;
+    memcpy4(RING_BUF, temp_sound_buffer+r, SAMPLES_TO_BYTES(n));
+  } else {
+    memcpy4(RING_BUF+fillpos, temp_sound_buffer, SAMPLES_TO_BYTES(n));
+  }
+  if((fillpos += n) >= curr_ring_buffer_samples)
+    fillpos = 0;
+}