Import the SCI engine sources from the FreeSCI Glutton branch (it doesn't compile yet)

svn-id: r38192

1 files changed, 184 insertions, 0 deletions

diff --git a/engines/sci/sfx/softseq/pcspeaker.c b/engines/sci/sfx/softseq/pcspeaker.c
new file mode 100644
index 0000000000..771c8f0da5
--- /dev/null
+++ b/engines/sci/sfx/softseq/pcspeaker.c
@@ -0,0 +1,184 @@
+/***************************************************************************
+ soft-pcspeaker.c  Copyright (C) 2004 Christoph Reichenbach
+
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public Licence as
+ published by the Free Software Foundaton; either version 2 of the
+ Licence, or (at your option) any later version.
+
+ It is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ merchantibility or fitness for a particular purpose. See the
+ GNU General Public Licence for more details.
+
+ You should have received a copy of the GNU General Public Licence
+ along with this program; see the file COPYING. If not, write to
+ the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+
+
+ Please contact the maintainer for any program-related bug reports or
+ inquiries.
+
+ Current Maintainer:
+
+    Christoph Reichenbach (CR) <jameson@linuxgames.com>
+
+***************************************************************************/
+/* PC speaker software sequencer for FreeSCI */
+
+#include "../softseq.h"
+#include <sci_midi.h>
+
+#define FREQUENCY 94020
+
+static int volume = 0x0600;
+static int note = 0; /* Current halftone, or 0 if off */
+static int freq_count = 0; 
+
+extern sfx_softseq_t sfx_softseq_pcspeaker;
+/* Forward-declare the sequencer we are defining here */
+
+
+static int
+sps_set_option(sfx_softseq_t *self, char *name, char *value)
+{
+	return SFX_ERROR;
+}
+
+static int
+sps_init(sfx_softseq_t *self, byte *patch, int patch_len, byte *patch2,
+	 int patch2_len)
+{
+	return SFX_OK;
+}
+
+static void
+sps_exit(sfx_softseq_t *self)
+{
+}
+
+static void
+sps_event(sfx_softseq_t *self, byte command, int argc, byte *argv)
+{
+#if 0
+	fprintf(stderr, "Note [%02x : %02x %02x]\n", command,  argc?argv[0] : 0, (argc > 1)? argv[1] : 0);
+#endif
+
+	switch (command & 0xf0) {
+
+	case 0x80:
+		if (argv[0] == note)
+			note = 0;
+		break;
+
+	case 0x90:
+		if (!argv[1]) {
+			if (argv[0] == note)
+				note = 0;
+		} else
+			note = argv[0];
+		/* Ignore velocity otherwise; we just use the global one */
+		break;
+
+	case 0xb0:
+		if (argv[1] == SCI_MIDI_CHANNEL_NOTES_OFF)
+			note = 0;
+		break;
+
+	default:
+#if DEBUG
+		fprintf(stderr, "[SFX:PCM-PC] Unused MIDI command %02x %02x %02x\n", command, argc?argv[0] : 0, (argc > 1)? argv[1] : 0);
+#endif
+		break; /* ignore */
+	}
+}
+
+#define BASE_NOTE 129	/* A10 */
+#define BASE_OCTAVE 10	/* A10, as I said */
+
+static int
+freq_table[12] = { /* A4 is 440Hz, halftone map is x |-> ** 2^(x/12) */
+	28160, /* A10 */
+	29834,
+	31608,
+	33488,
+	35479,
+	37589,
+	39824,
+	42192,
+	44701,
+	47359,
+	50175,
+	53159
+};
+
+
+void
+sps_poll(sfx_softseq_t *self, byte *dest, int len)
+{
+	int halftone_delta = note - BASE_NOTE;
+	int oct_diff = ((halftone_delta + BASE_OCTAVE * 12) / 12) - BASE_OCTAVE;
+	int halftone_index = (halftone_delta + (12*100)) % 12 ;
+	int freq = (!note)? 0 : freq_table[halftone_index] / (1 << (-oct_diff));
+	gint16 *buf = (gint16 *) dest;
+
+	int i;
+	for (i = 0; i < len; i++) {
+		if (note) {
+			freq_count += freq;
+			while (freq_count >= (FREQUENCY << 1))
+				freq_count -= (FREQUENCY << 1);
+
+			if (freq_count - freq < 0) {
+				/* Unclean rising edge */
+				int l = volume << 1;
+				buf[i] = -volume + (l*freq_count)/freq;
+			} else if (freq_count >= FREQUENCY
+				   && freq_count - freq < FREQUENCY) {
+				/* Unclean falling edge */
+				int l = volume << 1;
+				buf[i] = volume - (l*(freq_count - FREQUENCY))/freq;
+			} else {
+				if (freq_count < FREQUENCY)
+					buf[i] = volume;
+				else
+					buf[i] = -volume;
+			}
+		} else
+			buf[i] = 0;
+	}
+
+}
+
+void
+sps_volume(sfx_softseq_t *self, int new_volume)
+{
+	volume = new_volume << 4;
+}
+
+void
+sps_allstop(sfx_softseq_t *self)
+{
+	note = 0;
+}
+
+sfx_softseq_t sfx_softseq_pcspeaker = {
+	"pc-speaker",
+	"0.3",
+	sps_set_option,
+	sps_init,
+	sps_exit,
+	sps_volume,
+	sps_event,
+	sps_poll,
+	sps_allstop,
+	NULL,
+	SFX_SEQ_PATCHFILE_NONE,
+	SFX_SEQ_PATCHFILE_NONE,
+	0x20,  /* PC speaker channel only */
+	0, /* No rhythm channel */
+	1, /* # of voices */
+	{FREQUENCY, SFX_PCM_MONO, SFX_PCM_FORMAT_S16_NATIVE}
+};