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-rw-r--r--src/Makefile.am8
-rw-r--r--src/i_oplmusic.c1457
-rw-r--r--src/i_sdlmusic.c2
-rw-r--r--src/midifile.c815
-rw-r--r--src/midifile.h175
-rw-r--r--src/s_sound.c11
6 files changed, 2465 insertions, 3 deletions
diff --git a/src/Makefile.am b/src/Makefile.am
index 378ad053..8b827131 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -3,7 +3,7 @@ gamesdir = $(prefix)/games
games_PROGRAMS = chocolate-doom chocolate-server
-AM_CFLAGS = -I../textscreen -I../pcsound @SDLMIXER_CFLAGS@ @SDLNET_CFLAGS@
+AM_CFLAGS = -I../opl -I../textscreen -I../pcsound @SDLMIXER_CFLAGS@ @SDLNET_CFLAGS@
DEDSERV_FILES=\
d_dedicated.c \
@@ -155,6 +155,8 @@ FEATURE_SOUND_SOURCE_FILES = \
i_pcsound.c \
i_sdlsound.c \
i_sdlmusic.c \
+i_oplmusic.c \
+midifile.c midifile.h \
mus2mid.c mus2mid.h
SOURCE_FILES = $(MAIN_SOURCE_FILES) \
@@ -173,6 +175,7 @@ chocolate_doom_LDADD = \
../wince/libc_wince.a \
../textscreen/libtextscreen.a \
../pcsound/libpcsound.a \
+ ../opl/libopl.a \
@LDFLAGS@ \
@SDLMIXER_LIBS@ \
@SDLNET_LIBS@
@@ -193,3 +196,6 @@ icon.c : ../data/doom8.ico
endif
+midiread : midifile.c
+ $(CC) -DTEST $(CFLAGS) @LDFLAGS@ $^ -o $@
+
diff --git a/src/i_oplmusic.c b/src/i_oplmusic.c
new file mode 100644
index 00000000..9501d51d
--- /dev/null
+++ b/src/i_oplmusic.c
@@ -0,0 +1,1457 @@
+// Emacs style mode select -*- C++ -*-
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 1993-1996 Id Software, Inc.
+// Copyright(C) 2005 Simon Howard
+//
+// 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.
+//
+// DESCRIPTION:
+// System interface for music.
+//
+//-----------------------------------------------------------------------------
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "doomdef.h"
+#include "memio.h"
+#include "mus2mid.h"
+
+#include "deh_main.h"
+#include "i_swap.h"
+#include "m_misc.h"
+#include "s_sound.h"
+#include "w_wad.h"
+#include "z_zone.h"
+
+#include "opl.h"
+#include "midifile.h"
+
+#define MAXMIDLENGTH (96 * 1024)
+#define GENMIDI_NUM_INSTRS 128
+
+#define GENMIDI_HEADER "#OPL_II#"
+#define GENMIDI_FLAG_FIXED 0x0001 /* fixed pitch */
+#define GENMIDI_FLAG_2VOICE 0x0004 /* double voice (OPL3) */
+
+typedef struct
+{
+ byte tremolo;
+ byte attack;
+ byte sustain;
+ byte waveform;
+ byte scale;
+ byte level;
+} PACKEDATTR genmidi_op_t;
+
+typedef struct
+{
+ genmidi_op_t modulator;
+ byte feedback;
+ genmidi_op_t carrier;
+ byte unused;
+ short base_note_offset;
+} PACKEDATTR genmidi_voice_t;
+
+typedef struct
+{
+ unsigned short flags;
+ byte fine_tuning;
+ byte fixed_note;
+
+ genmidi_voice_t voices[2];
+} PACKEDATTR genmidi_instr_t;
+
+// Data associated with a channel of a track that is currently playing.
+
+typedef struct
+{
+ // The instrument currently used for this track.
+
+ genmidi_instr_t *instrument;
+
+ // Volume level
+
+ int volume;
+
+ // Pitch bend value:
+
+ int bend;
+
+} opl_channel_data_t;
+
+// Data associated with a track that is currently playing.
+
+typedef struct
+{
+ // Data for each channel.
+
+ opl_channel_data_t channels[MIDI_CHANNELS_PER_TRACK];
+
+ // Track iterator used to read new events.
+
+ midi_track_iter_t *iter;
+
+ // Tempo control variables
+
+ unsigned int ticks_per_beat;
+ unsigned int ms_per_beat;
+} opl_track_data_t;
+
+typedef struct opl_voice_s opl_voice_t;
+
+struct opl_voice_s
+{
+ // Index of this voice:
+ int index;
+
+ // The operators used by this voice:
+ int op1, op2;
+
+ // Currently-loaded instrument data
+ genmidi_instr_t *current_instr;
+
+ // The voice number in the instrument to use.
+ // This is normally set to zero; if this is a double voice
+ // instrument, it may be one.
+ unsigned int current_instr_voice;
+
+ // The channel currently using this voice.
+ opl_channel_data_t *channel;
+
+ // The midi key that this voice is playing.
+ unsigned int key;
+
+ // The note being played. This is normally the same as
+ // the key, but if the instrument is a fixed pitch
+ // instrument, it is different.
+ unsigned int note;
+
+ // The frequency value being used.
+ unsigned int freq;
+
+ // The volume of the note being played on this channel.
+ unsigned int note_volume;
+
+ // The current volume (register value) that has been set for this channel.
+ unsigned int reg_volume;
+
+ // Next in linked list; a voice is always either in the
+ // free list or the allocated list.
+ opl_voice_t *next;
+};
+
+// Operators used by the different voices.
+
+static const int voice_operators[2][OPL_NUM_VOICES] = {
+ { 0x00, 0x01, 0x02, 0x08, 0x09, 0x0a, 0x10, 0x11, 0x12 },
+ { 0x03, 0x04, 0x05, 0x0b, 0x0c, 0x0d, 0x13, 0x14, 0x15 }
+};
+
+// Frequency values to use for each note.
+
+static const unsigned short frequency_curve[] = {
+
+ 0x133, 0x133, 0x134, 0x134, 0x135, 0x136, 0x136, 0x137, // -1
+ 0x137, 0x138, 0x138, 0x139, 0x139, 0x13a, 0x13b, 0x13b,
+ 0x13c, 0x13c, 0x13d, 0x13d, 0x13e, 0x13f, 0x13f, 0x140,
+ 0x140, 0x141, 0x142, 0x142, 0x143, 0x143, 0x144, 0x144,
+
+ 0x145, 0x146, 0x146, 0x147, 0x147, 0x148, 0x149, 0x149, // -2
+ 0x14a, 0x14a, 0x14b, 0x14c, 0x14c, 0x14d, 0x14d, 0x14e,
+ 0x14f, 0x14f, 0x150, 0x150, 0x151, 0x152, 0x152, 0x153,
+ 0x153, 0x154, 0x155, 0x155, 0x156, 0x157, 0x157, 0x158,
+
+ // These are used for the first seven MIDI note values:
+
+ 0x158, 0x159, 0x15a, 0x15a, 0x15b, 0x15b, 0x15c, 0x15d, // 0
+ 0x15d, 0x15e, 0x15f, 0x15f, 0x160, 0x161, 0x161, 0x162,
+ 0x162, 0x163, 0x164, 0x164, 0x165, 0x166, 0x166, 0x167,
+ 0x168, 0x168, 0x169, 0x16a, 0x16a, 0x16b, 0x16c, 0x16c,
+
+ 0x16d, 0x16e, 0x16e, 0x16f, 0x170, 0x170, 0x171, 0x172, // 1
+ 0x172, 0x173, 0x174, 0x174, 0x175, 0x176, 0x176, 0x177,
+ 0x178, 0x178, 0x179, 0x17a, 0x17a, 0x17b, 0x17c, 0x17c,
+ 0x17d, 0x17e, 0x17e, 0x17f, 0x180, 0x181, 0x181, 0x182,
+
+ 0x183, 0x183, 0x184, 0x185, 0x185, 0x186, 0x187, 0x188, // 2
+ 0x188, 0x189, 0x18a, 0x18a, 0x18b, 0x18c, 0x18d, 0x18d,
+ 0x18e, 0x18f, 0x18f, 0x190, 0x191, 0x192, 0x192, 0x193,
+ 0x194, 0x194, 0x195, 0x196, 0x197, 0x197, 0x198, 0x199,
+
+ 0x19a, 0x19a, 0x19b, 0x19c, 0x19d, 0x19d, 0x19e, 0x19f, // 3
+ 0x1a0, 0x1a0, 0x1a1, 0x1a2, 0x1a3, 0x1a3, 0x1a4, 0x1a5,
+ 0x1a6, 0x1a6, 0x1a7, 0x1a8, 0x1a9, 0x1a9, 0x1aa, 0x1ab,
+ 0x1ac, 0x1ad, 0x1ad, 0x1ae, 0x1af, 0x1b0, 0x1b0, 0x1b1,
+
+ 0x1b2, 0x1b3, 0x1b4, 0x1b4, 0x1b5, 0x1b6, 0x1b7, 0x1b8, // 4
+ 0x1b8, 0x1b9, 0x1ba, 0x1bb, 0x1bc, 0x1bc, 0x1bd, 0x1be,
+ 0x1bf, 0x1c0, 0x1c0, 0x1c1, 0x1c2, 0x1c3, 0x1c4, 0x1c4,
+ 0x1c5, 0x1c6, 0x1c7, 0x1c8, 0x1c9, 0x1c9, 0x1ca, 0x1cb,
+
+ 0x1cc, 0x1cd, 0x1ce, 0x1ce, 0x1cf, 0x1d0, 0x1d1, 0x1d2, // 5
+ 0x1d3, 0x1d3, 0x1d4, 0x1d5, 0x1d6, 0x1d7, 0x1d8, 0x1d8,
+ 0x1d9, 0x1da, 0x1db, 0x1dc, 0x1dd, 0x1de, 0x1de, 0x1df,
+ 0x1e0, 0x1e1, 0x1e2, 0x1e3, 0x1e4, 0x1e5, 0x1e5, 0x1e6,
+
+ 0x1e7, 0x1e8, 0x1e9, 0x1ea, 0x1eb, 0x1ec, 0x1ed, 0x1ed, // 6
+ 0x1ee, 0x1ef, 0x1f0, 0x1f1, 0x1f2, 0x1f3, 0x1f4, 0x1f5,
+ 0x1f6, 0x1f6, 0x1f7, 0x1f8, 0x1f9, 0x1fa, 0x1fb, 0x1fc,
+ 0x1fd, 0x1fe, 0x1ff, 0x200, 0x201, 0x201, 0x202, 0x203,
+
+ // First note of looped range used for all octaves:
+
+ 0x204, 0x205, 0x206, 0x207, 0x208, 0x209, 0x20a, 0x20b, // 7
+ 0x20c, 0x20d, 0x20e, 0x20f, 0x210, 0x210, 0x211, 0x212,
+ 0x213, 0x214, 0x215, 0x216, 0x217, 0x218, 0x219, 0x21a,
+ 0x21b, 0x21c, 0x21d, 0x21e, 0x21f, 0x220, 0x221, 0x222,
+
+ 0x223, 0x224, 0x225, 0x226, 0x227, 0x228, 0x229, 0x22a, // 8
+ 0x22b, 0x22c, 0x22d, 0x22e, 0x22f, 0x230, 0x231, 0x232,
+ 0x233, 0x234, 0x235, 0x236, 0x237, 0x238, 0x239, 0x23a,
+ 0x23b, 0x23c, 0x23d, 0x23e, 0x23f, 0x240, 0x241, 0x242,
+
+ 0x244, 0x245, 0x246, 0x247, 0x248, 0x249, 0x24a, 0x24b, // 9
+ 0x24c, 0x24d, 0x24e, 0x24f, 0x250, 0x251, 0x252, 0x253,
+ 0x254, 0x256, 0x257, 0x258, 0x259, 0x25a, 0x25b, 0x25c,
+ 0x25d, 0x25e, 0x25f, 0x260, 0x262, 0x263, 0x264, 0x265,
+
+ 0x266, 0x267, 0x268, 0x269, 0x26a, 0x26c, 0x26d, 0x26e, // 10
+ 0x26f, 0x270, 0x271, 0x272, 0x273, 0x275, 0x276, 0x277,
+ 0x278, 0x279, 0x27a, 0x27b, 0x27d, 0x27e, 0x27f, 0x280,
+ 0x281, 0x282, 0x284, 0x285, 0x286, 0x287, 0x288, 0x289,
+
+ 0x28b, 0x28c, 0x28d, 0x28e, 0x28f, 0x290, 0x292, 0x293, // 11
+ 0x294, 0x295, 0x296, 0x298, 0x299, 0x29a, 0x29b, 0x29c,
+ 0x29e, 0x29f, 0x2a0, 0x2a1, 0x2a2, 0x2a4, 0x2a5, 0x2a6,
+ 0x2a7, 0x2a9, 0x2aa, 0x2ab, 0x2ac, 0x2ae, 0x2af, 0x2b0,
+
+ 0x2b1, 0x2b2, 0x2b4, 0x2b5, 0x2b6, 0x2b7, 0x2b9, 0x2ba, // 12
+ 0x2bb, 0x2bd, 0x2be, 0x2bf, 0x2c0, 0x2c2, 0x2c3, 0x2c4,
+ 0x2c5, 0x2c7, 0x2c8, 0x2c9, 0x2cb, 0x2cc, 0x2cd, 0x2ce,
+ 0x2d0, 0x2d1, 0x2d2, 0x2d4, 0x2d5, 0x2d6, 0x2d8, 0x2d9,
+
+ 0x2da, 0x2dc, 0x2dd, 0x2de, 0x2e0, 0x2e1, 0x2e2, 0x2e4, // 13
+ 0x2e5, 0x2e6, 0x2e8, 0x2e9, 0x2ea, 0x2ec, 0x2ed, 0x2ee,
+ 0x2f0, 0x2f1, 0x2f2, 0x2f4, 0x2f5, 0x2f6, 0x2f8, 0x2f9,
+ 0x2fb, 0x2fc, 0x2fd, 0x2ff, 0x300, 0x302, 0x303, 0x304,
+
+ 0x306, 0x307, 0x309, 0x30a, 0x30b, 0x30d, 0x30e, 0x310, // 14
+ 0x311, 0x312, 0x314, 0x315, 0x317, 0x318, 0x31a, 0x31b,
+ 0x31c, 0x31e, 0x31f, 0x321, 0x322, 0x324, 0x325, 0x327,
+ 0x328, 0x329, 0x32b, 0x32c, 0x32e, 0x32f, 0x331, 0x332,
+
+ 0x334, 0x335, 0x337, 0x338, 0x33a, 0x33b, 0x33d, 0x33e, // 15
+ 0x340, 0x341, 0x343, 0x344, 0x346, 0x347, 0x349, 0x34a,
+ 0x34c, 0x34d, 0x34f, 0x350, 0x352, 0x353, 0x355, 0x357,
+ 0x358, 0x35a, 0x35b, 0x35d, 0x35e, 0x360, 0x361, 0x363,
+
+ 0x365, 0x366, 0x368, 0x369, 0x36b, 0x36c, 0x36e, 0x370, // 16
+ 0x371, 0x373, 0x374, 0x376, 0x378, 0x379, 0x37b, 0x37c,
+ 0x37e, 0x380, 0x381, 0x383, 0x384, 0x386, 0x388, 0x389,
+ 0x38b, 0x38d, 0x38e, 0x390, 0x392, 0x393, 0x395, 0x397,
+
+ 0x398, 0x39a, 0x39c, 0x39d, 0x39f, 0x3a1, 0x3a2, 0x3a4, // 17
+ 0x3a6, 0x3a7, 0x3a9, 0x3ab, 0x3ac, 0x3ae, 0x3b0, 0x3b1,
+ 0x3b3, 0x3b5, 0x3b7, 0x3b8, 0x3ba, 0x3bc, 0x3bd, 0x3bf,
+ 0x3c1, 0x3c3, 0x3c4, 0x3c6, 0x3c8, 0x3ca, 0x3cb, 0x3cd,
+
+ // The last note has an incomplete range, and loops round back to
+ // the start. Note that the last value is actually a buffer overrun
+ // and does not fit with the other values.
+
+ 0x3cf, 0x3d1, 0x3d2, 0x3d4, 0x3d6, 0x3d8, 0x3da, 0x3db, // 18
+ 0x3dd, 0x3df, 0x3e1, 0x3e3, 0x3e4, 0x3e6, 0x3e8, 0x3ea,
+ 0x3ec, 0x3ed, 0x3ef, 0x3f1, 0x3f3, 0x3f5, 0x3f6, 0x3f8,
+ 0x3fa, 0x3fc, 0x3fe, 0x36c,
+};
+
+// Mapping from MIDI volume level to OPL level value.
+
+static const unsigned int volume_mapping_table[] = {
+ 0, 1, 3, 5, 6, 8, 10, 11,
+ 13, 14, 16, 17, 19, 20, 22, 23,
+ 25, 26, 27, 29, 30, 32, 33, 34,
+ 36, 37, 39, 41, 43, 45, 47, 49,
+ 50, 52, 54, 55, 57, 59, 60, 61,
+ 63, 64, 66, 67, 68, 69, 71, 72,
+ 73, 74, 75, 76, 77, 79, 80, 81,
+ 82, 83, 84, 84, 85, 86, 87, 88,
+ 89, 90, 91, 92, 92, 93, 94, 95,
+ 96, 96, 97, 98, 99, 99, 100, 101,
+ 101, 102, 103, 103, 104, 105, 105, 106,
+ 107, 107, 108, 109, 109, 110, 110, 111,
+ 112, 112, 113, 113, 114, 114, 115, 115,
+ 116, 117, 117, 118, 118, 119, 119, 120,
+ 120, 121, 121, 122, 122, 123, 123, 123,
+ 124, 124, 125, 125, 126, 126, 127, 127
+};
+
+static boolean music_initialized = false;
+
+//static boolean musicpaused = false;
+static int current_music_volume;
+
+// GENMIDI lump instrument data:
+
+static genmidi_instr_t *main_instrs;
+static genmidi_instr_t *percussion_instrs;
+
+// Voices:
+
+static opl_voice_t voices[OPL_NUM_VOICES];
+static opl_voice_t *voice_free_list;
+static opl_voice_t *voice_alloced_list;
+
+// Track data for playing tracks:
+
+static opl_track_data_t *tracks;
+static unsigned int num_tracks = 0;
+static unsigned int running_tracks = 0;
+static boolean song_looping;
+
+// Configuration file variable, containing the port number for the
+// adlib chip.
+
+int opl_io_port = 0x388;
+
+// Load instrument table from GENMIDI lump:
+
+static boolean LoadInstrumentTable(void)
+{
+ byte *lump;
+
+ lump = W_CacheLumpName("GENMIDI", PU_STATIC);
+
+ // Check header
+
+ if (strncmp((char *) lump, GENMIDI_HEADER, strlen(GENMIDI_HEADER)) != 0)
+ {
+ W_ReleaseLumpName("GENMIDI");
+
+ return false;
+ }
+
+ main_instrs = (genmidi_instr_t *) (lump + strlen(GENMIDI_HEADER));
+ percussion_instrs = main_instrs + GENMIDI_NUM_INSTRS;
+
+ return true;
+}
+
+// Get the next available voice from the freelist.
+
+static opl_voice_t *GetFreeVoice(void)
+{
+ opl_voice_t *result;
+
+ // None available?
+
+ if (voice_free_list == NULL)
+ {
+ return NULL;
+ }
+
+ // Remove from free list
+
+ result = voice_free_list;
+ voice_free_list = voice_free_list->next;
+
+ // Add to allocated list
+
+ result->next = voice_alloced_list;
+ voice_alloced_list = result;
+
+ return result;
+}
+
+// Remove a voice from the allocated voices list.
+
+static void RemoveVoiceFromAllocedList(opl_voice_t *voice)
+{
+ opl_voice_t **rover;
+
+ rover = &voice_alloced_list;
+
+ // Search the list until we find the voice, then remove it.
+
+ while (*rover != NULL)
+ {
+ if (*rover == voice)
+ {
+ *rover = voice->next;
+ voice->next = NULL;
+ break;
+ }
+
+ rover = &(*rover)->next;
+ }
+}
+
+// Release a voice back to the freelist.
+
+static void ReleaseVoice(opl_voice_t *voice)
+{
+ opl_voice_t **rover;
+
+ voice->channel = NULL;
+ voice->note = 0;
+
+ // Remove from alloced list.
+
+ RemoveVoiceFromAllocedList(voice);
+
+ // Search to the end of the freelist (This is how Doom behaves!)
+
+ rover = &voice_free_list;
+
+ while (*rover != NULL)
+ {
+ rover = &(*rover)->next;
+ }
+
+ *rover = voice;
+ voice->next = NULL;
+}
+
+// Load data to the specified operator
+
+static void LoadOperatorData(int operator, genmidi_op_t *data,
+ boolean max_level)
+{
+ int level;
+
+ // The scale and level fields must be combined for the level register.
+ // For the carrier wave we always set the maximum level.
+
+ level = (data->scale & 0xc0) | (data->level & 0x3f);
+
+ if (max_level)
+ {
+ level |= 0x3f;
+ }
+
+ OPL_WriteRegister(OPL_REGS_LEVEL + operator, level);
+ OPL_WriteRegister(OPL_REGS_TREMOLO + operator, data->tremolo);
+ OPL_WriteRegister(OPL_REGS_ATTACK + operator, data->attack);
+ OPL_WriteRegister(OPL_REGS_SUSTAIN + operator, data->sustain);
+ OPL_WriteRegister(OPL_REGS_WAVEFORM + operator, data->waveform);
+}
+
+// Set the instrument for a particular voice.
+
+static void SetVoiceInstrument(opl_voice_t *voice,
+ genmidi_instr_t *instr,
+ unsigned int instr_voice)
+{
+ genmidi_voice_t *data;
+ unsigned int modulating;
+
+ // Instrument already set for this channel?
+
+ if (voice->current_instr == instr
+ && voice->current_instr_voice == instr_voice)
+ {
+ return;
+ }
+
+ voice->current_instr = instr;
+ voice->current_instr_voice = instr_voice;
+
+ data = &instr->voices[instr_voice];
+
+ // Are we usind modulated feedback mode?
+
+ modulating = (data->feedback & 0x01) == 0;
+
+ // Doom loads the second operator first, then the first.
+ // The carrier is set to minimum volume until the voice volume
+ // is set in SetVoiceVolume (below). If we are not using
+ // modulating mode, we must set both to minimum volume.
+
+ LoadOperatorData(voice->op2, &data->carrier, true);
+ LoadOperatorData(voice->op1, &data->modulator, !modulating);
+
+ // Set feedback register that control the connection between the
+ // two operators. Turn on bits in the upper nybble; I think this
+ // is for OPL3, where it turns on channel A/B.
+
+ OPL_WriteRegister(OPL_REGS_FEEDBACK + voice->index,
+ data->feedback | 0x30);
+
+ // Hack to force a volume update.
+
+ voice->reg_volume = 999;
+}
+
+static void SetVoiceVolume(opl_voice_t *voice, unsigned int volume)
+{
+ genmidi_voice_t *opl_voice;
+ unsigned int full_volume;
+ unsigned int op_volume;
+ unsigned int reg_volume;
+
+ voice->note_volume = volume;
+
+ opl_voice = &voice->current_instr->voices[voice->current_instr_voice];
+
+ // Multiply note volume and channel volume to get the actual volume.
+
+ full_volume = (volume_mapping_table[voice->note_volume]
+ * volume_mapping_table[voice->channel->volume]
+ * volume_mapping_table[current_music_volume]) / (127 * 127);
+
+ // The volume of each instrument can be controlled via GENMIDI:
+
+ op_volume = 0x3f - opl_voice->carrier.level;
+
+ // The volume value to use in the register:
+
+ reg_volume = (op_volume * full_volume) / 128;
+ reg_volume = (0x3f - reg_volume) | opl_voice->carrier.scale;
+
+ // Update the volume register(s) if necessary.
+
+ if (reg_volume != voice->reg_volume)
+ {
+ voice->reg_volume = reg_volume;
+
+ OPL_WriteRegister(OPL_REGS_LEVEL + voice->op2, reg_volume);
+
+ // If we are using non-modulated feedback mode, we must set the
+ // volume for both voices.
+ // Note that the same register volume value is written for
+ // both voices, always calculated from the carrier's level
+ // value.
+
+ if ((opl_voice->feedback & 0x01) != 0)
+ {
+ OPL_WriteRegister(OPL_REGS_LEVEL + voice->op1, reg_volume);
+ }
+ }
+}
+
+// Initialize the voice table and freelist
+
+static void InitVoices(void)
+{
+ int i;
+
+ // Start with an empty free list.
+
+ voice_free_list = NULL;
+
+ // Initialize each voice.
+
+ for (i=0; i<OPL_NUM_VOICES; ++i)
+ {
+ voices[i].index = i;
+ voices[i].op1 = voice_operators[0][i];
+ voices[i].op2 = voice_operators[1][i];
+ voices[i].current_instr = NULL;
+
+ // Add this voice to the freelist.
+
+ ReleaseVoice(&voices[i]);
+ }
+}
+
+// Set music volume (0 - 127)
+
+static void I_OPL_SetMusicVolume(int volume)
+{
+ unsigned int i;
+
+ // Internal state variable.
+
+ current_music_volume = volume;
+
+ // Update the volume of all voices.
+
+ for (i=0; i<OPL_NUM_VOICES; ++i)
+ {
+ if (voices[i].channel != NULL)
+ {
+ SetVoiceVolume(&voices[i], voices[i].note_volume);
+ }
+ }
+}
+
+static void VoiceKeyOff(opl_voice_t *voice)
+{
+ OPL_WriteRegister(OPL_REGS_FREQ_2 + voice->index, voice->freq >> 8);
+}
+
+// Get the frequency that we should be using for a voice.
+
+static void KeyOffEvent(opl_track_data_t *track, midi_event_t *event)
+{
+ opl_channel_data_t *channel;
+ unsigned int key;
+ unsigned int i;
+
+/*
+ printf("note off: channel %i, %i, %i\n",
+ event->data.channel.channel,
+ event->data.channel.param1,
+ event->data.channel.param2);
+*/
+
+ channel = &track->channels[event->data.channel.channel];
+ key = event->data.channel.param1;
+
+ // Turn off voices being used to play this key.
+ // If it is a double voice instrument there will be two.
+
+ for (i=0; i<OPL_NUM_VOICES; ++i)
+ {
+ if (voices[i].channel == channel && voices[i].key == key)
+ {
+ VoiceKeyOff(&voices[i]);
+
+ // Finished with this voice now.
+
+ ReleaseVoice(&voices[i]);
+ }
+ }
+}
+
+// Compare the priorities of channels, returning either -1, 0 or 1.
+
+static int CompareChannelPriorities(opl_channel_data_t *chan1,
+ opl_channel_data_t *chan2)
+{
+ // TODO ...
+
+ return 1;
+}
+
+// When all voices are in use, we must discard an existing voice to
+// play a new note. Find and free an existing voice. The channel
+// passed to the function is the channel for the new note to be
+// played.
+
+static opl_voice_t *ReplaceExistingVoice(opl_channel_data_t *channel)
+{
+ opl_voice_t *rover;
+ opl_voice_t *result;
+
+ // Check the allocated voices, if we find an instrument that is
+ // of a lower priority to the new instrument, discard it.
+ // If a voice is being used to play the second voice of an instrument,
+ // use that, as second voices are non-essential.
+ // Lower numbered MIDI channels implicitly have a higher priority
+ // than higher-numbered channels, eg. MIDI channel 1 is never
+ // discarded for MIDI channel 2.
+
+ result = NULL;
+
+ for (rover = voice_alloced_list; rover != NULL; rover = rover->next)
+ {
+ if (rover->current_instr_voice != 0
+ || (rover->channel > channel
+ && CompareChannelPriorities(channel, rover->channel) > 0))
+ {
+ result = rover;
+ break;
+ }
+ }
+
+ // If we didn't find a voice, find an existing voice being used to
+ // play a note on the same channel, and use that.
+
+ if (result == NULL)
+ {
+ for (rover = voice_alloced_list; rover != NULL; rover = rover->next)
+ {
+ if (rover->channel == channel)
+ {
+ result = rover;
+ break;
+ }
+ }
+ }
+
+ // Still nothing found? Give up and just use the first voice in
+ // the list.
+
+ if (result == NULL)
+ {
+ result = voice_alloced_list;
+ }
+
+ // Stop playing this voice playing and release it back to the free
+ // list.
+
+ VoiceKeyOff(result);
+ ReleaseVoice(result);
+
+ // Re-allocate the voice again and return it.
+
+ return GetFreeVoice();
+}
+
+
+static unsigned int FrequencyForVoice(opl_voice_t *voice)
+{
+ genmidi_voice_t *gm_voice;
+ unsigned int freq_index;
+ unsigned int octave;
+ unsigned int sub_index;
+ unsigned int note;
+
+ note = voice->note;
+
+ // Apply note offset.
+ // Don't apply offset if the instrument is a fixed note instrument.
+
+ gm_voice = &voice->current_instr->voices[voice->current_instr_voice];
+
+ if ((voice->current_instr->flags & GENMIDI_FLAG_FIXED) == 0)
+ {
+ note += (signed short) SHORT(gm_voice->base_note_offset);
+ }
+
+ // Avoid possible overflow due to base note offset:
+
+ if (note > 0x7f)
+ {
+ note = voice->note;
+ }
+
+ freq_index = 64 + 32 * note + voice->channel->bend;
+
+ // If this is the second voice of a double voice instrument, the
+ // frequency index can be adjusted by the fine tuning field.
+
+ if (voice->current_instr_voice != 0)
+ {
+ freq_index += (voice->current_instr->fine_tuning / 2) - 64;
+ }
+
+ // The first 7 notes use the start of the table, while
+ // consecutive notes loop around the latter part.
+
+ if (freq_index < 284)
+ {
+ return frequency_curve[freq_index];
+ }
+
+ sub_index = (freq_index - 284) % (12 * 32);
+ octave = (freq_index - 284) / (12 * 32);
+
+ // Once the seventh octave is reached, things break down.
+ // We can only go up to octave 7 as a maximum anyway (the OPL
+ // register only has three bits for octave number), but for the
+ // notes in octave 7, the first five bits have octave=7, the
+ // following notes have octave=6. This 7/6 pattern repeats in
+ // following octaves (which are technically impossible to
+ // represent anyway).
+
+ if (octave >= 7)
+ {
+ if (sub_index < 5)
+ {
+ octave = 7;
+ }
+ else
+ {
+ octave = 6;
+ }
+ }
+
+ // Calculate the resulting register value to use for the frequency.
+
+ return frequency_curve[sub_index + 284] | (octave << 10);
+}
+
+// Update the frequency that a voice is programmed to use.
+
+static void UpdateVoiceFrequency(opl_voice_t *voice)
+{
+ unsigned int freq;
+
+ // Calculate the frequency to use for this voice and update it
+ // if neccessary.
+
+ freq = FrequencyForVoice(voice);
+
+ if (voice->freq != freq)
+ {
+ OPL_WriteRegister(OPL_REGS_FREQ_1 + voice->index, freq & 0xff);
+ OPL_WriteRegister(OPL_REGS_FREQ_2 + voice->index, (freq >> 8) | 0x20);
+
+ voice->freq = freq;
+ }
+}
+
+// Program a single voice for an instrument. For a double voice
+// instrument (GENMIDI_FLAG_2VOICE), this is called twice for each
+// key on event.
+
+static void VoiceKeyOn(opl_channel_data_t *channel,
+ genmidi_instr_t *instrument,
+ unsigned int instrument_voice,
+ unsigned int key,
+ unsigned int volume)
+{
+ opl_voice_t *voice;
+
+ // Find a voice to use for this new note.
+
+ voice = GetFreeVoice();
+
+ // If there are no more voices left, we must decide what to do.
+ // If this is the first voice of the instrument, free an existing
+ // voice and use that. Otherwise, if this is the second voice,
+ // it isn't as important; just discard it.
+
+ if (voice == NULL)
+ {
+ if (instrument_voice == 0)
+ {
+ voice = ReplaceExistingVoice(channel);
+ }
+ else
+ {
+ return;
+ }
+ }
+
+ voice->channel = channel;
+ voice->key = key;
+
+ // Work out the note to use. This is normally the same as
+ // the key, unless it is a fixed pitch instrument.
+
+ if ((instrument->flags & GENMIDI_FLAG_FIXED) != 0)
+ {
+ voice->note = instrument->fixed_note;
+ }
+ else
+ {
+ voice->note = key;
+ }
+
+ // Program the voice with the instrument data:
+
+ SetVoiceInstrument(voice, instrument, instrument_voice);
+
+ // Set the volume level.
+
+ SetVoiceVolume(voice, volume);
+
+ // Write the frequency value to turn the note on.
+
+ voice->freq = 0;
+ UpdateVoiceFrequency(voice);
+}
+
+static void KeyOnEvent(opl_track_data_t *track, midi_event_t *event)
+{
+ genmidi_instr_t *instrument;
+ opl_channel_data_t *channel;
+ unsigned int key;
+ unsigned int volume;
+
+/*
+ printf("note on: channel %i, %i, %i\n",
+ event->data.channel.channel,
+ event->data.channel.param1,
+ event->data.channel.param2);
+*/
+
+ // The channel.
+
+ channel = &track->channels[event->data.channel.channel];
+ key = event->data.channel.param1;
+ volume = event->data.channel.param2;
+
+ // Percussion channel (10) is treated differently.
+
+ if (event->data.channel.channel == 9)
+ {
+ if (key < 35 || key > 81)
+ {
+ return;
+ }
+
+ instrument = &percussion_instrs[key - 35];
+ }
+ else
+ {
+ instrument = channel->instrument;
+ }
+
+ // Find and program a voice for this instrument. If this
+ // is a double voice instrument, we must do this twice.
+
+ VoiceKeyOn(channel, instrument, 0, key, volume);
+
+ if ((instrument->flags & GENMIDI_FLAG_2VOICE) != 0)
+ {
+ VoiceKeyOn(channel, instrument, 1, key, volume);
+ }
+}
+
+static void ProgramChangeEvent(opl_track_data_t *track, midi_event_t *event)
+{
+ int channel;
+ int instrument;
+
+ // Set the instrument used on this channel.
+
+ channel = event->data.channel.channel;
+ instrument = event->data.channel.param1;
+ track->channels[channel].instrument = &main_instrs[instrument];
+
+ // TODO: Look through existing voices that are turned on on this
+ // channel, and change the instrument.
+}
+
+static void SetChannelVolume(opl_channel_data_t *channel, unsigned int volume)
+{
+ unsigned int i;
+
+ channel->volume = volume;
+
+ // Update all voices that this channel is using.
+
+ for (i=0; i<OPL_NUM_VOICES; ++i)
+ {
+ if (voices[i].channel == channel)
+ {
+ SetVoiceVolume(&voices[i], voices[i].note_volume);
+ }
+ }
+}
+
+static void ControllerEvent(opl_track_data_t *track, midi_event_t *event)
+{
+ unsigned int controller;
+ unsigned int param;
+ opl_channel_data_t *channel;
+
+/*
+ printf("change controller: channel %i, %i, %i\n",
+ event->data.channel.channel,
+ event->data.channel.param1,
+ event->data.channel.param2);
+*/
+
+ channel = &track->channels[event->data.channel.channel];
+ controller = event->data.channel.param1;
+ param = event->data.channel.param2;
+
+ switch (controller)
+ {
+ case MIDI_CONTROLLER_MAIN_VOLUME:
+ SetChannelVolume(channel, param);
+ break;
+
+ default:
+ fprintf(stderr, "Unknown MIDI controller type: %i\n", controller);
+ break;
+ }
+}
+
+// Process a pitch bend event.
+
+static void PitchBendEvent(opl_track_data_t *track, midi_event_t *event)
+{
+ opl_channel_data_t *channel;
+ unsigned int i;
+
+ // Update the channel bend value. Only the MSB of the pitch bend
+ // value is considered: this is what Doom does.
+
+ channel = &track->channels[event->data.channel.channel];
+ channel->bend = event->data.channel.param2 - 64;
+
+ // Update all voices for this channel.
+
+ for (i=0; i<OPL_NUM_VOICES; ++i)
+ {
+ if (voices[i].channel == channel)
+ {
+ UpdateVoiceFrequency(&voices[i]);
+ }
+ }
+}
+
+// Process a meta event.
+
+static void MetaEvent(opl_track_data_t *track, midi_event_t *event)
+{
+ switch (event->data.meta.type)
+ {
+ // Things we can just ignore.
+
+ case MIDI_META_SEQUENCE_NUMBER:
+ case MIDI_META_TEXT:
+ case MIDI_META_COPYRIGHT:
+ case MIDI_META_TRACK_NAME:
+ case MIDI_META_INSTR_NAME:
+ case MIDI_META_LYRICS:
+ case MIDI_META_MARKER:
+ case MIDI_META_CUE_POINT:
+ case MIDI_META_SEQUENCER_SPECIFIC:
+ break;
+
+ // End of track - actually handled when we run out of events
+ // in the track, see below.
+
+ case MIDI_META_END_OF_TRACK:
+ break;
+
+ default:
+ fprintf(stderr, "Unknown MIDI meta event type: %i\n",
+ event->data.meta.type);
+ break;
+ }
+}
+
+// Process a MIDI event from a track.
+
+static void ProcessEvent(opl_track_data_t *track, midi_event_t *event)
+{
+ switch (event->event_type)
+ {
+ case MIDI_EVENT_NOTE_OFF:
+ KeyOffEvent(track, event);
+ break;
+
+ case MIDI_EVENT_NOTE_ON:
+ KeyOnEvent(track, event);
+ break;
+
+ case MIDI_EVENT_CONTROLLER:
+ ControllerEvent(track, event);
+ break;
+
+ case MIDI_EVENT_PROGRAM_CHANGE:
+ ProgramChangeEvent(track, event);
+ break;
+
+ case MIDI_EVENT_PITCH_BEND:
+ PitchBendEvent(track, event);
+ break;
+
+ case MIDI_EVENT_META:
+ MetaEvent(track, event);
+ break;
+
+ // SysEx events can be ignored.
+
+ case MIDI_EVENT_SYSEX:
+ case MIDI_EVENT_SYSEX_SPLIT:
+ break;
+
+ default:
+ fprintf(stderr, "Unknown MIDI event type %i\n", event->event_type);
+ break;
+ }
+}
+
+static void ScheduleTrack(opl_track_data_t *track);
+
+// Restart a song from the beginning.
+
+static void RestartSong(void)
+{
+ unsigned int i;
+
+ running_tracks = num_tracks;
+
+ for (i=0; i<num_tracks; ++i)
+ {
+ MIDI_RestartIterator(tracks[i].iter);
+ ScheduleTrack(&tracks[i]);
+ }
+}
+
+// Callback function invoked when another event needs to be read from
+// a track.
+
+static void TrackTimerCallback(void *arg)
+{
+ opl_track_data_t *track = arg;
+ midi_event_t *event;
+
+ // Get the next event and process it.
+
+ if (!MIDI_GetNextEvent(track->iter, &event))
+ {
+ return;
+ }
+
+ ProcessEvent(track, event);
+
+ // End of track?
+
+ if (event->event_type == MIDI_EVENT_META
+ && event->data.meta.type == MIDI_META_END_OF_TRACK)
+ {
+ --running_tracks;
+
+ // When all tracks have finished, restart the song.
+
+ if (running_tracks <= 0 && song_looping)
+ {
+ RestartSong();
+ }
+
+ return;
+ }
+
+ // Reschedule the callback for the next event in the track.
+
+ ScheduleTrack(track);
+}
+
+static void ScheduleTrack(opl_track_data_t *track)
+{
+ unsigned int nticks;
+ unsigned int ms;
+ static int total = 0;
+
+ // Get the number of milliseconds until the next event.
+
+ nticks = MIDI_GetDeltaTime(track->iter);
+ ms = (nticks * track->ms_per_beat) / track->ticks_per_beat;
+ total += ms;
+
+ // Set a timer to be invoked when the next event is
+ // ready to play.
+
+ OPL_SetCallback(ms, TrackTimerCallback, track);
+}
+
+// Initialize a channel.
+
+static void InitChannel(opl_track_data_t *track, opl_channel_data_t *channel)
+{
+ // TODO: Work out sensible defaults?
+
+ channel->instrument = &main_instrs[0];
+ channel->volume = 127;
+ channel->bend = 0;
+}
+
+// Start a MIDI track playing:
+
+static void StartTrack(midi_file_t *file, unsigned int track_num)
+{
+ opl_track_data_t *track;
+ unsigned int i;
+
+ track = &tracks[track_num];
+ track->iter = MIDI_IterateTrack(file, track_num);
+ track->ticks_per_beat = MIDI_GetFileTimeDivision(file);
+
+ // Default is 120 bpm.
+ // TODO: this is wrong
+
+ track->ms_per_beat = 500 * 260;
+
+ for (i=0; i<MIDI_CHANNELS_PER_TRACK; ++i)
+ {
+ InitChannel(track, &track->channels[i]);
+ }
+
+ // Schedule the first event.
+
+ ScheduleTrack(track);
+}
+
+// Start playing a mid
+
+static void I_OPL_PlaySong(void *handle, int looping)
+{
+ midi_file_t *file;
+ unsigned int i;
+
+ if (!music_initialized || handle == NULL)
+ {
+ return;
+ }
+
+ file = handle;
+
+ // Allocate track data.
+
+ tracks = malloc(MIDI_NumTracks(file) * sizeof(opl_track_data_t));
+
+ num_tracks = MIDI_NumTracks(file);
+ running_tracks = num_tracks;
+ song_looping = looping;
+
+ for (i=0; i<num_tracks; ++i)
+ {
+ StartTrack(file, i);
+ }
+}
+
+static void I_OPL_PauseSong(void)
+{
+ unsigned int i;
+
+ if (!music_initialized)
+ {
+ return;
+ }
+
+ // Pause OPL callbacks.
+
+ OPL_SetPaused(1);
+
+ // Turn off all main instrument voices (not percussion).
+ // This is what Vanilla does.
+
+ for (i=0; i<OPL_NUM_VOICES; ++i)
+ {
+ if (voices[i].channel != NULL
+ && voices[i].current_instr < percussion_instrs)
+ {
+ VoiceKeyOff(&voices[i]);
+ }
+ }
+}
+
+static void I_OPL_ResumeSong(void)
+{
+ if (!music_initialized)
+ {
+ return;
+ }
+
+ OPL_SetPaused(0);
+}
+
+static void I_OPL_StopSong(void)
+{
+ unsigned int i;
+
+ if (!music_initialized)
+ {
+ return;
+ }
+
+ OPL_Lock();
+
+ // Stop all playback.
+
+ OPL_ClearCallbacks();
+
+ // Free all voices.
+
+ for (i=0; i<OPL_NUM_VOICES; ++i)
+ {
+ if (voices[i].channel != NULL)
+ {
+ VoiceKeyOff(&voices[i]);
+ ReleaseVoice(&voices[i]);
+ }
+ }
+
+ // Free all track data.
+
+ for (i=0; i<num_tracks; ++i)
+ {
+ MIDI_FreeIterator(tracks[i].iter);
+ }
+
+ free(tracks);
+
+ tracks = NULL;
+ num_tracks = 0;
+
+ OPL_Unlock();
+}
+
+static void I_OPL_UnRegisterSong(void *handle)
+{
+ if (!music_initialized)
+ {
+ return;
+ }
+
+ if (handle != NULL)
+ {
+ MIDI_FreeFile(handle);
+ }
+}
+
+// Determine whether memory block is a .mid file
+
+static boolean IsMid(byte *mem, int len)
+{
+ return len > 4 && !memcmp(mem, "MThd", 4);
+}
+
+static boolean ConvertMus(byte *musdata, int len, char *filename)
+{
+ MEMFILE *instream;
+ MEMFILE *outstream;
+ void *outbuf;
+ size_t outbuf_len;
+ int result;
+
+ instream = mem_fopen_read(musdata, len);
+ outstream = mem_fopen_write();
+
+ result = mus2mid(instream, outstream);
+
+ if (result == 0)
+ {
+ mem_get_buf(outstream, &outbuf, &outbuf_len);
+
+ M_WriteFile(filename, outbuf, outbuf_len);
+ }
+
+ mem_fclose(instream);
+ mem_fclose(outstream);
+
+ return result;
+}
+
+static void *I_OPL_RegisterSong(void *data, int len)
+{
+ midi_file_t *result;
+ char *filename;
+
+ if (!music_initialized)
+ {
+ return NULL;
+ }
+
+ // MUS files begin with "MUS"
+ // Reject anything which doesnt have this signature
+
+ filename = M_TempFile("doom.mid");
+
+ if (IsMid(data, len) && len < MAXMIDLENGTH)
+ {
+ M_WriteFile(filename, data, len);
+ }
+ else
+ {
+ // Assume a MUS file and try to convert
+
+ ConvertMus(data, len, filename);
+ }
+
+ result = MIDI_LoadFile(filename);
+
+ if (result == NULL)
+ {
+ fprintf(stderr, "I_OPL_RegisterSong: Failed to load MID.\n");
+ }
+
+ // remove file now
+
+ remove(filename);
+
+ Z_Free(filename);
+
+ return result;
+}
+
+// Is the song playing?
+
+static boolean I_OPL_MusicIsPlaying(void)
+{
+ if (!music_initialized)
+ {
+ return false;
+ }
+
+ return num_tracks > 0;
+}
+
+// Shutdown music
+
+static void I_OPL_ShutdownMusic(void)
+{
+ if (music_initialized)
+ {
+ // Stop currently-playing track, if there is one:
+
+ I_OPL_StopSong();
+
+ OPL_Shutdown();
+
+ // Release GENMIDI lump
+
+ W_ReleaseLumpName("GENMIDI");
+
+ music_initialized = false;
+ }
+}
+
+// Initialize music subsystem
+
+static boolean I_OPL_InitMusic(void)
+{
+ OPL_SetSampleRate(snd_samplerate);
+
+ if (!OPL_Init(opl_io_port))
+ {
+ printf("Dude. The Adlib isn't responding.\n");
+ return false;
+ }
+
+ // Load instruments from GENMIDI lump:
+
+ if (!LoadInstrumentTable())
+ {
+ OPL_Shutdown();
+ return false;
+ }
+
+ InitVoices();
+
+ tracks = NULL;
+ num_tracks = 0;
+ music_initialized = true;
+
+ return true;
+}
+
+static snddevice_t music_opl_devices[] =
+{
+ SNDDEVICE_ADLIB,
+ SNDDEVICE_SB,
+};
+
+music_module_t music_opl_module =
+{
+ music_opl_devices,
+ arrlen(music_opl_devices),
+ I_OPL_InitMusic,
+ I_OPL_ShutdownMusic,
+ I_OPL_SetMusicVolume,
+ I_OPL_PauseSong,
+ I_OPL_ResumeSong,
+ I_OPL_RegisterSong,
+ I_OPL_UnRegisterSong,
+ I_OPL_PlaySong,
+ I_OPL_StopSong,
+ I_OPL_MusicIsPlaying,
+};
+
diff --git a/src/i_sdlmusic.c b/src/i_sdlmusic.c
index 7f9bd8ec..4aa89add 100644
--- a/src/i_sdlmusic.c
+++ b/src/i_sdlmusic.c
@@ -334,8 +334,6 @@ static boolean I_SDL_MusicIsPlaying(void)
static snddevice_t music_sdl_devices[] =
{
- SNDDEVICE_ADLIB,
- SNDDEVICE_SB,
SNDDEVICE_PAS,
SNDDEVICE_GUS,
SNDDEVICE_WAVEBLASTER,
diff --git a/src/midifile.c b/src/midifile.c
new file mode 100644
index 00000000..bd935ca1
--- /dev/null
+++ b/src/midifile.c
@@ -0,0 +1,815 @@
+// Emacs style mode select -*- C++ -*-
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2009 Simon Howard
+//
+// 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.
+//
+// DESCRIPTION:
+// Reading of MIDI files.
+//
+//-----------------------------------------------------------------------------
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+#include "doomdef.h"
+#include "doomtype.h"
+#include "i_swap.h"
+#include "midifile.h"
+
+#define HEADER_CHUNK_ID "MThd"
+#define TRACK_CHUNK_ID "MTrk"
+#define MAX_BUFFER_SIZE 0x10000
+
+typedef struct
+{
+ byte chunk_id[4];
+ unsigned int chunk_size;
+} PACKEDATTR chunk_header_t;
+
+typedef struct
+{
+ chunk_header_t chunk_header;
+ unsigned short format_type;
+ unsigned short num_tracks;
+ unsigned short time_division;
+} PACKEDATTR midi_header_t;
+
+typedef struct
+{
+ // Length in bytes:
+
+ unsigned int data_len;
+
+ // Events in this track:
+
+ midi_event_t *events;
+ int num_events;
+} midi_track_t;
+
+struct midi_track_iter_s
+{
+ midi_track_t *track;
+ unsigned int position;
+};
+
+struct midi_file_s
+{
+ midi_header_t header;
+
+ // All tracks in this file:
+ midi_track_t *tracks;
+ unsigned int num_tracks;
+
+ // Data buffer used to store data read for SysEx or meta events:
+ byte *buffer;
+ unsigned int buffer_size;
+};
+
+// Check the header of a chunk:
+
+static boolean CheckChunkHeader(chunk_header_t *chunk,
+ char *expected_id)
+{
+ boolean result;
+
+ result = (memcmp((char *) chunk->chunk_id, expected_id, 4) == 0);
+
+ if (!result)
+ {
+ fprintf(stderr, "CheckChunkHeader: Expected '%s' chunk header, "
+ "got '%c%c%c%c'\n",
+ expected_id,
+ chunk->chunk_id[0], chunk->chunk_id[1],
+ chunk->chunk_id[2], chunk->chunk_id[3]);
+ }
+
+ return result;
+}
+
+// Read a single byte. Returns false on error.
+
+static boolean ReadByte(byte *result, FILE *stream)
+{
+ int c;
+
+ c = fgetc(stream);
+
+ if (c == EOF)
+ {
+ fprintf(stderr, "ReadByte: Unexpected end of file\n");
+ return false;
+ }
+ else
+ {
+ *result = (byte) c;
+
+ return true;
+ }
+}
+
+// Read a variable-length value.
+
+static boolean ReadVariableLength(unsigned int *result, FILE *stream)
+{
+ int i;
+ byte b;
+
+ *result = 0;
+
+ for (i=0; i<4; ++i)
+ {
+ if (!ReadByte(&b, stream))
+ {
+ fprintf(stderr, "ReadVariableLength: Error while reading "
+ "variable-length value\n");
+ return false;
+ }
+
+ // Insert the bottom seven bits from this byte.
+
+ *result <<= 7;
+ *result |= b & 0x7f;
+
+ // If the top bit is not set, this is the end.
+
+ if ((b & 0x80) == 0)
+ {
+ return true;
+ }
+ }
+
+ fprintf(stderr, "ReadVariableLength: Variable-length value too "
+ "long: maximum of four bytes\n");
+ return false;
+}
+
+// Read a byte sequence into the data buffer.
+
+static void *ReadByteSequence(unsigned int num_bytes, FILE *stream)
+{
+ unsigned int i;
+ byte *result;
+
+ // Allocate a buffer:
+
+ result = malloc(num_bytes);
+
+ if (result == NULL)
+ {
+ fprintf(stderr, "ReadByteSequence: Failed to allocate buffer\n");
+ return NULL;
+ }
+
+ // Read the data:
+
+ for (i=0; i<num_bytes; ++i)
+ {
+ if (!ReadByte(&result[i], stream))
+ {
+ fprintf(stderr, "ReadByteSequence: Error while reading byte %u\n",
+ i);
+ free(result);
+ return NULL;
+ }
+ }
+
+ return result;
+}
+
+// Read a MIDI channel event.
+// two_param indicates that the event type takes two parameters
+// (three byte) otherwise it is single parameter (two byte)
+
+static boolean ReadChannelEvent(midi_event_t *event,
+ byte event_type, boolean two_param,
+ FILE *stream)
+{
+ byte b;
+
+ // Set basics:
+
+ event->event_type = event_type & 0xf0;
+ event->data.channel.channel = event_type & 0x0f;
+
+ // Read parameters:
+
+ if (!ReadByte(&b, stream))
+ {
+ fprintf(stderr, "ReadChannelEvent: Error while reading channel "
+ "event parameters\n");
+ return false;
+ }
+
+ event->data.channel.param1 = b;
+
+ // Second parameter:
+
+ if (two_param)
+ {
+ if (!ReadByte(&b, stream))
+ {
+ fprintf(stderr, "ReadChannelEvent: Error while reading channel "
+ "event parameters\n");
+ return false;
+ }
+
+ event->data.channel.param2 = b;
+ }
+
+ return true;
+}
+
+// Read sysex event:
+
+static boolean ReadSysExEvent(midi_event_t *event, int event_type,
+ FILE *stream)
+{
+ event->event_type = event_type;
+
+ if (!ReadVariableLength(&event->data.sysex.length, stream))
+ {
+ fprintf(stderr, "ReadSysExEvent: Failed to read length of "
+ "SysEx block\n");
+ return false;
+ }
+
+ // Read the byte sequence:
+
+ event->data.sysex.data = ReadByteSequence(event->data.sysex.length, stream);
+
+ if (event->data.sysex.data == NULL)
+ {
+ fprintf(stderr, "ReadSysExEvent: Failed while reading SysEx event\n");
+ return false;
+ }
+
+ return true;
+}
+
+// Read meta event:
+
+static boolean ReadMetaEvent(midi_event_t *event, FILE *stream)
+{
+ byte b;
+
+ event->event_type = MIDI_EVENT_META;
+
+ // Read meta event type:
+
+ if (!ReadByte(&b, stream))
+ {
+ fprintf(stderr, "ReadMetaEvent: Failed to read meta event type\n");
+ return false;
+ }
+
+ event->data.meta.type = b;
+
+ // Read length of meta event data:
+
+ if (!ReadVariableLength(&event->data.meta.length, stream))
+ {
+ fprintf(stderr, "ReadSysExEvent: Failed to read length of "
+ "SysEx block\n");
+ return false;
+ }
+
+ // Read the byte sequence:
+
+ event->data.meta.data = ReadByteSequence(event->data.meta.length, stream);
+
+ if (event->data.meta.data == NULL)
+ {
+ fprintf(stderr, "ReadSysExEvent: Failed while reading SysEx event\n");
+ return false;
+ }
+
+ return true;
+}
+
+static boolean ReadEvent(midi_event_t *event, unsigned int *last_event_type,
+ FILE *stream)
+{
+ byte event_type;
+
+ if (!ReadVariableLength(&event->delta_time, stream))
+ {
+ fprintf(stderr, "ReadEvent: Failed to read event timestamp\n");
+ return false;
+ }
+
+ if (!ReadByte(&event_type, stream))
+ {
+ fprintf(stderr, "ReadEvent: Failed to read event type\n");
+ return false;
+ }
+
+ // All event types have their top bit set. Therefore, if
+ // the top bit is not set, it is because we are using the "same
+ // as previous event type" shortcut to save a byte. Skip back
+ // a byte so that we read this byte again.
+
+ if ((event_type & 0x80) == 0)
+ {
+ event_type = *last_event_type;
+
+ if (fseek(stream, -1, SEEK_CUR) < 0)
+ {
+ fprintf(stderr, "ReadEvent: Unable to seek in stream\n");
+ return false;
+ }
+ }
+ else
+ {
+ *last_event_type = event_type;
+ }
+
+ // Check event type:
+
+ switch (event_type & 0xf0)
+ {
+ // Two parameter channel events:
+
+ case MIDI_EVENT_NOTE_OFF:
+ case MIDI_EVENT_NOTE_ON:
+ case MIDI_EVENT_AFTERTOUCH:
+ case MIDI_EVENT_CONTROLLER:
+ case MIDI_EVENT_PITCH_BEND:
+ return ReadChannelEvent(event, event_type, true, stream);
+
+ // Single parameter channel events:
+
+ case MIDI_EVENT_PROGRAM_CHANGE:
+ case MIDI_EVENT_CHAN_AFTERTOUCH:
+ return ReadChannelEvent(event, event_type, false, stream);
+
+ default:
+ break;
+ }
+
+ // Specific value?
+
+ switch (event_type)
+ {
+ case MIDI_EVENT_SYSEX:
+ case MIDI_EVENT_SYSEX_SPLIT:
+ return ReadSysExEvent(event, event_type, stream);
+
+ case MIDI_EVENT_META:
+ return ReadMetaEvent(event, stream);
+
+ default:
+ break;
+ }
+
+ fprintf(stderr, "ReadEvent: Unknown MIDI event type: 0x%x\n", event_type);
+ return false;
+}
+
+// Free an event:
+
+static void FreeEvent(midi_event_t *event)
+{
+ // Some event types have dynamically allocated buffers assigned
+ // to them that must be freed.
+
+ switch (event->event_type)
+ {
+ case MIDI_EVENT_SYSEX:
+ case MIDI_EVENT_SYSEX_SPLIT:
+ free(event->data.sysex.data);
+ break;
+
+ case MIDI_EVENT_META:
+ free(event->data.meta.data);
+ break;
+
+ default:
+ // Nothing to do.
+ break;
+ }
+}
+
+// Read and check the track chunk header
+
+static boolean ReadTrackHeader(midi_track_t *track, FILE *stream)
+{
+ size_t records_read;
+ chunk_header_t chunk_header;
+
+ records_read = fread(&chunk_header, sizeof(chunk_header_t), 1, stream);
+
+ if (records_read < 1)
+ {
+ return false;
+ }
+
+ if (!CheckChunkHeader(&chunk_header, TRACK_CHUNK_ID))
+ {
+ return false;
+ }
+
+ track->data_len = SDL_SwapBE32(chunk_header.chunk_size);
+
+ return true;
+}
+
+static boolean ReadTrack(midi_track_t *track, FILE *stream)
+{
+ midi_event_t *new_events;
+ midi_event_t *event;
+ unsigned int last_event_type;
+
+ track->num_events = 0;
+ track->events = NULL;
+
+ // Read the header:
+
+ if (!ReadTrackHeader(track, stream))
+ {
+ return false;
+ }
+
+ // Then the events:
+
+ last_event_type = 0;
+
+ for (;;)
+ {
+ // Resize the track slightly larger to hold another event:
+
+ new_events = realloc(track->events,
+ sizeof(midi_event_t) * (track->num_events + 1));
+
+ if (new_events == NULL)
+ {
+ return false;
+ }
+
+ track->events = new_events;
+
+ // Read the next event:
+
+ event = &track->events[track->num_events];
+ if (!ReadEvent(event, &last_event_type, stream))
+ {
+ return false;
+ }
+
+ ++track->num_events;
+
+ // End of track?
+
+ if (event->event_type == MIDI_EVENT_META
+ && event->data.meta.type == MIDI_META_END_OF_TRACK)
+ {
+ break;
+ }
+ }
+
+ return true;
+}
+
+// Free a track:
+
+static void FreeTrack(midi_track_t *track)
+{
+ unsigned int i;
+
+ for (i=0; i<track->num_events; ++i)
+ {
+ FreeEvent(&track->events[i]);
+ }
+
+ free(track->events);
+}
+
+static boolean ReadAllTracks(midi_file_t *file, FILE *stream)
+{
+ unsigned int i;
+
+ // Allocate list of tracks and read each track:
+
+ file->tracks = malloc(sizeof(midi_track_t) * file->num_tracks);
+
+ if (file->tracks == NULL)
+ {
+ return false;
+ }
+
+ memset(file->tracks, 0, sizeof(midi_track_t) * file->num_tracks);
+
+ // Read each track:
+
+ for (i=0; i<file->num_tracks; ++i)
+ {
+ if (!ReadTrack(&file->tracks[i], stream))
+ {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+// Read and check the header chunk.
+
+static boolean ReadFileHeader(midi_file_t *file, FILE *stream)
+{
+ size_t records_read;
+ unsigned int format_type;
+
+ records_read = fread(&file->header, sizeof(midi_header_t), 1, stream);
+
+ if (records_read < 1)
+ {
+ return false;
+ }
+
+ if (!CheckChunkHeader(&file->header.chunk_header, HEADER_CHUNK_ID)
+ || SDL_SwapBE32(file->header.chunk_header.chunk_size) != 6)
+ {
+ fprintf(stderr, "ReadFileHeader: Invalid MIDI chunk header! "
+ "chunk_size=%i\n",
+ SDL_SwapBE32(file->header.chunk_header.chunk_size));
+ return false;
+ }
+
+ format_type = SDL_SwapBE16(file->header.format_type);
+ file->num_tracks = SDL_SwapBE16(file->header.num_tracks);
+
+ if ((format_type != 0 && format_type != 1)
+ || file->num_tracks < 1)
+ {
+ fprintf(stderr, "ReadFileHeader: Only type 0/1 "
+ "MIDI files supported!\n");
+ return false;
+ }
+
+ return true;
+}
+
+void MIDI_FreeFile(midi_file_t *file)
+{
+ int i;
+
+ if (file->tracks != NULL)
+ {
+ for (i=0; i<file->num_tracks; ++i)
+ {
+ FreeTrack(&file->tracks[i]);
+ }
+
+ free(file->tracks);
+ }
+
+ free(file);
+}
+
+midi_file_t *MIDI_LoadFile(char *filename)
+{
+ midi_file_t *file;
+ FILE *stream;
+
+ file = malloc(sizeof(midi_file_t));
+
+ if (file == NULL)
+ {
+ return NULL;
+ }
+
+ file->tracks = NULL;
+ file->num_tracks = 0;
+ file->buffer = NULL;
+ file->buffer_size = 0;
+
+ // Open file
+
+ stream = fopen(filename, "rb");
+
+ if (stream == NULL)
+ {
+ fprintf(stderr, "MIDI_LoadFile: Failed to open '%s'\n", filename);
+ MIDI_FreeFile(file);
+ return NULL;
+ }
+
+ // Read MIDI file header
+
+ if (!ReadFileHeader(file, stream))
+ {
+ fclose(stream);
+ MIDI_FreeFile(file);
+ return NULL;
+ }
+
+ // Read all tracks:
+
+ if (!ReadAllTracks(file, stream))
+ {
+ fclose(stream);
+ MIDI_FreeFile(file);
+ return NULL;
+ }
+
+ fclose(stream);
+
+ return file;
+}
+
+// Get the number of tracks in a MIDI file.
+
+unsigned int MIDI_NumTracks(midi_file_t *file)
+{
+ return file->num_tracks;
+}
+
+// Start iterating over the events in a track.
+
+midi_track_iter_t *MIDI_IterateTrack(midi_file_t *file, unsigned int track)
+{
+ midi_track_iter_t *iter;
+
+ assert(track < file->num_tracks);
+
+ iter = malloc(sizeof(*iter));
+ iter->track = &file->tracks[track];
+ iter->position = 0;
+
+ return iter;
+}
+
+void MIDI_FreeIterator(midi_track_iter_t *iter)
+{
+ free(iter);
+}
+
+// Get the time until the next MIDI event in a track.
+
+unsigned int MIDI_GetDeltaTime(midi_track_iter_t *iter)
+{
+ if (iter->position < iter->track->num_events)
+ {
+ midi_event_t *next_event;
+
+ next_event = &iter->track->events[iter->position];
+
+ return next_event->delta_time;
+ }
+ else
+ {
+ return 0;
+ }
+}
+
+// Get a pointer to the next MIDI event.
+
+int MIDI_GetNextEvent(midi_track_iter_t *iter, midi_event_t **event)
+{
+ if (iter->position < iter->track->num_events)
+ {
+ *event = &iter->track->events[iter->position];
+ ++iter->position;
+
+ return 1;
+ }
+ else
+ {
+ return 0;
+ }
+}
+
+unsigned int MIDI_GetFileTimeDivision(midi_file_t *file)
+{
+ return file->header.time_division;
+}
+
+void MIDI_RestartIterator(midi_track_iter_t *iter)
+{
+ iter->position = 0;
+}
+
+#ifdef TEST
+
+static char *MIDI_EventTypeToString(midi_event_type_t event_type)
+{
+ switch (event_type)
+ {
+ case MIDI_EVENT_NOTE_OFF:
+ return "MIDI_EVENT_NOTE_OFF";
+ case MIDI_EVENT_NOTE_ON:
+ return "MIDI_EVENT_NOTE_ON";
+ case MIDI_EVENT_AFTERTOUCH:
+ return "MIDI_EVENT_AFTERTOUCH";
+ case MIDI_EVENT_CONTROLLER:
+ return "MIDI_EVENT_CONTROLLER";
+ case MIDI_EVENT_PROGRAM_CHANGE:
+ return "MIDI_EVENT_PROGRAM_CHANGE";
+ case MIDI_EVENT_CHAN_AFTERTOUCH:
+ return "MIDI_EVENT_CHAN_AFTERTOUCH";
+ case MIDI_EVENT_PITCH_BEND:
+ return "MIDI_EVENT_PITCH_BEND";
+ case MIDI_EVENT_SYSEX:
+ return "MIDI_EVENT_SYSEX";
+ case MIDI_EVENT_SYSEX_SPLIT:
+ return "MIDI_EVENT_SYSEX_SPLIT";
+ case MIDI_EVENT_META:
+ return "MIDI_EVENT_META";
+
+ default:
+ return "(unknown)";
+ }
+}
+
+void PrintTrack(midi_track_t *track)
+{
+ midi_event_t *event;
+ unsigned int i;
+
+ for (i=0; i<track->num_events; ++i)
+ {
+ event = &track->events[i];
+
+ if (event->delta_time > 0)
+ {
+ printf("Delay: %i ticks\n", event->delta_time);
+ }
+
+ printf("Event type: %s (%i)\n",
+ MIDI_EventTypeToString(event->event_type),
+ event->event_type);
+
+ switch(event->event_type)
+ {
+ case MIDI_EVENT_NOTE_OFF:
+ case MIDI_EVENT_NOTE_ON:
+ case MIDI_EVENT_AFTERTOUCH:
+ case MIDI_EVENT_CONTROLLER:
+ case MIDI_EVENT_PROGRAM_CHANGE:
+ case MIDI_EVENT_CHAN_AFTERTOUCH:
+ case MIDI_EVENT_PITCH_BEND:
+ printf("\tChannel: %i\n", event->data.channel.channel);
+ printf("\tParameter 1: %i\n", event->data.channel.param1);
+ printf("\tParameter 2: %i\n", event->data.channel.param2);
+ break;
+
+ case MIDI_EVENT_SYSEX:
+ case MIDI_EVENT_SYSEX_SPLIT:
+ printf("\tLength: %i\n", event->data.sysex.length);
+ break;
+
+ case MIDI_EVENT_META:
+ printf("\tMeta type: %i\n", event->data.meta.type);
+ printf("\tLength: %i\n", event->data.meta.length);
+ break;
+ }
+ }
+}
+
+int main(int argc, char *argv[])
+{
+ midi_file_t *file;
+ unsigned int i;
+
+ if (argc < 2)
+ {
+ printf("Usage: %s <filename>\n", argv[0]);
+ exit(1);
+ }
+
+ file = MIDI_LoadFile(argv[1]);
+
+ if (file == NULL)
+ {
+ fprintf(stderr, "Failed to open %s\n", argv[1]);
+ exit(1);
+ }
+
+ for (i=0; i<file->num_tracks; ++i)
+ {
+ printf("\n== Track %i ==\n\n", i);
+
+ PrintTrack(&file->tracks[i]);
+ }
+
+ return 0;
+}
+
+#endif
+
diff --git a/src/midifile.h b/src/midifile.h
new file mode 100644
index 00000000..4ee0ddb2
--- /dev/null
+++ b/src/midifile.h
@@ -0,0 +1,175 @@
+// Emacs style mode select -*- C++ -*-
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2009 Simon Howard
+//
+// 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.
+//
+// DESCRIPTION:
+// MIDI file parsing.
+//
+//-----------------------------------------------------------------------------
+
+#ifndef MIDIFILE_H
+#define MIDIFILE_H
+
+typedef struct midi_file_s midi_file_t;
+typedef struct midi_track_iter_s midi_track_iter_t;
+
+#define MIDI_CHANNELS_PER_TRACK 16
+
+typedef enum
+{
+ MIDI_EVENT_NOTE_OFF = 0x80,
+ MIDI_EVENT_NOTE_ON = 0x90,
+ MIDI_EVENT_AFTERTOUCH = 0xa0,
+ MIDI_EVENT_CONTROLLER = 0xb0,
+ MIDI_EVENT_PROGRAM_CHANGE = 0xc0,
+ MIDI_EVENT_CHAN_AFTERTOUCH = 0xd0,
+ MIDI_EVENT_PITCH_BEND = 0xe0,
+
+ MIDI_EVENT_SYSEX = 0xf0,
+ MIDI_EVENT_SYSEX_SPLIT = 0xf7,
+ MIDI_EVENT_META = 0xff,
+} midi_event_type_t;
+
+typedef enum
+{
+ MIDI_CONTROLLER_BANK_SELECT = 0x0,
+ MIDI_CONTROLLER_MODULATION = 0x1,
+ MIDI_CONTROLLER_BREATH_CONTROL = 0x2,
+ MIDI_CONTROLLER_FOOT_CONTROL = 0x3,
+ MIDI_CONTROLLER_PORTAMENTO = 0x4,
+ MIDI_CONTROLLER_DATA_ENTRY = 0x5,
+
+ MIDI_CONTROLLER_MAIN_VOLUME = 0x7,
+ MIDI_CONTROLLER_PAN = 0xa
+} midi_controller_t;
+
+typedef enum
+{
+ MIDI_META_SEQUENCE_NUMBER = 0x0,
+
+ MIDI_META_TEXT = 0x1,
+ MIDI_META_COPYRIGHT = 0x2,
+ MIDI_META_TRACK_NAME = 0x3,
+ MIDI_META_INSTR_NAME = 0x4,
+ MIDI_META_LYRICS = 0x5,
+ MIDI_META_MARKER = 0x6,
+ MIDI_META_CUE_POINT = 0x7,
+
+ MIDI_META_CHANNEL_PREFIX = 0x20,
+ MIDI_META_END_OF_TRACK = 0x2f,
+
+ MIDI_META_SET_TEMPO = 0x51,
+ MIDI_META_SMPTE_OFFSET = 0x54,
+ MIDI_META_TIME_SIGNATURE = 0x58,
+ MIDI_META_KEY_SIGNATURE = 0x59,
+ MIDI_META_SEQUENCER_SPECIFIC = 0x7f,
+} midi_meta_event_type_t;
+
+typedef struct
+{
+ // Meta event type:
+
+ unsigned int type;
+
+ // Length:
+
+ unsigned int length;
+
+ // Meta event data:
+
+ byte *data;
+} midi_meta_event_data_t;
+
+typedef struct
+{
+ // Length:
+
+ unsigned int length;
+
+ // Event data:
+
+ byte *data;
+} midi_sysex_event_data_t;
+
+typedef struct
+{
+ // The channel number to which this applies:
+
+ unsigned int channel;
+
+ // Extra parameters:
+
+ unsigned int param1;
+ unsigned int param2;
+} midi_channel_event_data_t;
+
+typedef struct
+{
+ // Time between the previous event and this event.
+ unsigned int delta_time;
+
+ // Type of event:
+ midi_event_type_t event_type;
+
+ union
+ {
+ midi_channel_event_data_t channel;
+ midi_meta_event_data_t meta;
+ midi_sysex_event_data_t sysex;
+ } data;
+} midi_event_t;
+
+// Load a MIDI file.
+
+midi_file_t *MIDI_LoadFile(char *filename);
+
+// Free a MIDI file.
+
+void MIDI_FreeFile(midi_file_t *file);
+
+// Get the time division value from the MIDI header.
+
+unsigned int MIDI_GetFileTimeDivision(midi_file_t *file);
+
+// Get the number of tracks in a MIDI file.
+
+unsigned int MIDI_NumTracks(midi_file_t *file);
+
+// Start iterating over the events in a track.
+
+midi_track_iter_t *MIDI_IterateTrack(midi_file_t *file, unsigned int track_num);
+
+// Free an iterator.
+
+void MIDI_FreeIterator(midi_track_iter_t *iter);
+
+// Get the time until the next MIDI event in a track.
+
+unsigned int MIDI_GetDeltaTime(midi_track_iter_t *iter);
+
+// Get a pointer to the next MIDI event.
+
+int MIDI_GetNextEvent(midi_track_iter_t *iter, midi_event_t **event);
+
+// Reset an iterator to the beginning of a track.
+
+void MIDI_RestartIterator(midi_track_iter_t *iter);
+
+#endif /* #ifndef MIDIFILE_H */
+
diff --git a/src/s_sound.c b/src/s_sound.c
index 1c56efb2..6c18f65e 100644
--- a/src/s_sound.c
+++ b/src/s_sound.c
@@ -128,6 +128,7 @@ int snd_sfxdevice = SNDDEVICE_SB;
extern sound_module_t sound_sdl_module;
extern sound_module_t sound_pcsound_module;
extern music_module_t music_sdl_module;
+extern music_module_t music_opl_module;
// Compiled-in sound modules:
@@ -146,6 +147,7 @@ static music_module_t *music_modules[] =
{
#ifdef FEATURE_SOUND
&music_sdl_module,
+ &music_opl_module,
#endif
NULL,
};
@@ -794,6 +796,15 @@ void S_ChangeMusic(int musicnum, int looping)
char namebuf[9];
void *handle;
+ // The Doom IWAD file has two versions of the intro music: d_intro
+ // and d_introa. The latter is used for OPL playback.
+
+ if (musicnum == mus_intro && (snd_musicdevice == SNDDEVICE_ADLIB
+ || snd_musicdevice == SNDDEVICE_SB))
+ {
+ musicnum = mus_introa;
+ }
+
if (musicnum <= mus_None || musicnum >= NUMMUSIC)
{
I_Error("Bad music number %d", musicnum);