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Diffstat (limited to 'trunk/src/emu/sound/flt_vol.c')
-rw-r--r--trunk/src/emu/sound/flt_vol.c75
1 files changed, 75 insertions, 0 deletions
diff --git a/trunk/src/emu/sound/flt_vol.c b/trunk/src/emu/sound/flt_vol.c
new file mode 100644
index 00000000000..27b354be948
--- /dev/null
+++ b/trunk/src/emu/sound/flt_vol.c
@@ -0,0 +1,75 @@
+#include "emu.h"
+#include "flt_vol.h"
+
+
+typedef struct _filter_volume_state filter_volume_state;
+struct _filter_volume_state
+{
+ sound_stream * stream;
+ int gain;
+};
+
+INLINE filter_volume_state *get_safe_token(device_t *device)
+{
+ assert(device != NULL);
+ assert(device->type() == FILTER_VOLUME);
+ return (filter_volume_state *)downcast<legacy_device_base *>(device)->token();
+}
+
+
+
+static STREAM_UPDATE( filter_volume_update )
+{
+ stream_sample_t *src = inputs[0];
+ stream_sample_t *dst = outputs[0];
+ filter_volume_state *info = (filter_volume_state *)param;
+
+ while (samples--)
+ *dst++ = (*src++ * info->gain) >> 8;
+}
+
+
+static DEVICE_START( filter_volume )
+{
+ filter_volume_state *info = get_safe_token(device);
+
+ info->gain = 0x100;
+ info->stream = device->machine().sound().stream_alloc(*device, 1, 1, device->machine().sample_rate(), info, filter_volume_update);
+}
+
+
+void flt_volume_set_volume(device_t *device, float volume)
+{
+ filter_volume_state *info = get_safe_token(device);
+ info->gain = (int)(volume * 256);
+}
+
+
+
+/**************************************************************************
+ * Generic get_info
+ **************************************************************************/
+
+DEVICE_GET_INFO( filter_volume )
+{
+ switch (state)
+ {
+ /* --- the following bits of info are returned as 64-bit signed integers --- */
+ case DEVINFO_INT_TOKEN_BYTES: info->i = sizeof(filter_volume_state); break;
+
+ /* --- the following bits of info are returned as pointers to data or functions --- */
+ case DEVINFO_FCT_START: info->start = DEVICE_START_NAME( filter_volume ); break;
+ case DEVINFO_FCT_STOP: /* Nothing */ break;
+ case DEVINFO_FCT_RESET: /* Nothing */ break;
+
+ /* --- the following bits of info are returned as NULL-terminated strings --- */
+ case DEVINFO_STR_NAME: strcpy(info->s, "Volume Filter"); break;
+ case DEVINFO_STR_FAMILY: strcpy(info->s, "Filters"); break;
+ case DEVINFO_STR_VERSION: strcpy(info->s, "1.0"); break;
+ case DEVINFO_STR_SOURCE_FILE: strcpy(info->s, __FILE__); break;
+ case DEVINFO_STR_CREDITS: strcpy(info->s, "Copyright Nicola Salmoria and the MAME Team"); break;
+ }
+}
+
+
+DEFINE_LEGACY_SOUND_DEVICE(FILTER_VOLUME, filter_volume);