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Diffstat (limited to 'apps/codecs/libgme/sgc_emu.h')
-rw-r--r-- | apps/codecs/libgme/sgc_emu.h | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/apps/codecs/libgme/sgc_emu.h b/apps/codecs/libgme/sgc_emu.h new file mode 100644 index 0000000000..957e7438ef --- /dev/null +++ b/apps/codecs/libgme/sgc_emu.h | |||
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1 | // Sega/Game Gear/Coleco SGC music file emulator | ||
2 | |||
3 | // Game_Music_Emu 0.6-pre | ||
4 | #ifndef SGC_EMU_H | ||
5 | #define SGC_EMU_H | ||
6 | |||
7 | #include "blargg_common.h" | ||
8 | #include "multi_buffer.h" | ||
9 | |||
10 | #include "rom_data.h" | ||
11 | #include "z80_cpu.h" | ||
12 | #include "sms_fm_apu.h" | ||
13 | #include "sms_apu.h" | ||
14 | #include "m3u_playlist.h" | ||
15 | |||
16 | typedef short sample_t; | ||
17 | typedef struct Z80_Cpu Sgc_Cpu; | ||
18 | |||
19 | enum { buf_size = 2048 }; | ||
20 | |||
21 | // SGC file header | ||
22 | enum { header_size = 0xA0 }; | ||
23 | struct header_t | ||
24 | { | ||
25 | char tag [4]; // "SGC\x1A" | ||
26 | byte vers; // 0x01 | ||
27 | byte rate; // 0=NTSC 1=PAL | ||
28 | byte reserved1 [2]; | ||
29 | byte load_addr [2]; | ||
30 | byte init_addr [2]; | ||
31 | byte play_addr [2]; | ||
32 | byte stack_ptr [2]; | ||
33 | byte reserved2 [2]; | ||
34 | byte rst_addrs [7*2]; | ||
35 | byte mapping [4]; // Used by Sega only | ||
36 | byte first_song; // Song to start playing first | ||
37 | byte song_count; | ||
38 | byte first_effect; | ||
39 | byte last_effect; | ||
40 | byte system; // 0=Master System 1=Game Gear 2=Colecovision | ||
41 | byte reserved3 [23]; | ||
42 | char game [32]; // strings can be 32 chars, NOT terminated | ||
43 | char author [32]; | ||
44 | char copyright [32]; | ||
45 | }; | ||
46 | |||
47 | // True if header has valid file signature | ||
48 | static inline bool valid_tag( struct header_t* h ) | ||
49 | { | ||
50 | return 0 == memcmp( h->tag, "SGC\x1A", 4 ); | ||
51 | } | ||
52 | |||
53 | static inline int effect_count( struct header_t* h ) { return h->last_effect ? h->last_effect - h->first_effect + 1 : 0; } | ||
54 | |||
55 | |||
56 | struct Sgc_Emu { | ||
57 | bool fm_accessed; | ||
58 | |||
59 | cpu_time_t play_period; | ||
60 | cpu_time_t next_play; | ||
61 | void const* bank2; // ROM selected for bank 2, in case RAM is currently hiding it | ||
62 | addr_t vectors_addr; // RST vectors start here | ||
63 | addr_t idle_addr; // return address for init/play routines | ||
64 | void* coleco_bios; | ||
65 | |||
66 | // general | ||
67 | int voice_count; | ||
68 | int mute_mask_; | ||
69 | double tempo; | ||
70 | double gain; | ||
71 | |||
72 | long sample_rate; | ||
73 | |||
74 | // track-specific | ||
75 | volatile bool track_ended; | ||
76 | int current_track; | ||
77 | int track_count; | ||
78 | blargg_long out_time; // number of samples played since start of track | ||
79 | blargg_long emu_time; // number of samples emulator has generated since start of track | ||
80 | bool emu_track_ended_; // emulator has reached end of track | ||
81 | |||
82 | // fading | ||
83 | blargg_long fade_start; | ||
84 | int fade_step; | ||
85 | |||
86 | // silence detection | ||
87 | bool ignore_silence; | ||
88 | int max_initial_silence; | ||
89 | int silence_lookahead; // speed to run emulator when looking ahead for silence | ||
90 | long silence_time; // number of samples where most recent silence began | ||
91 | long silence_count; // number of samples of silence to play before using buf | ||
92 | long buf_remain; // number of samples left in silence buffer | ||
93 | |||
94 | long clock_rate_; | ||
95 | unsigned buf_changed_count; | ||
96 | |||
97 | // M3u Playlist | ||
98 | struct M3u_Playlist m3u; | ||
99 | |||
100 | sample_t buf [buf_size]; | ||
101 | struct Stereo_Buffer stereo_buf; | ||
102 | |||
103 | struct Sms_Apu apu; | ||
104 | struct Sms_Fm_Apu fm_apu; | ||
105 | |||
106 | Sgc_Cpu cpu; | ||
107 | |||
108 | // large items | ||
109 | struct header_t header; | ||
110 | struct Rom_Data rom; | ||
111 | byte vectors [page_size + page_padding]; | ||
112 | byte ram [0x2000 + page_padding]; | ||
113 | byte ram2 [0x4000 + page_padding]; | ||
114 | byte unmapped_write [0x4000]; | ||
115 | }; | ||
116 | |||
117 | // Basic functionality (see Gme_File.h for file loading/track info functions) | ||
118 | |||
119 | void Sgc_init( struct Sgc_Emu* this ); | ||
120 | |||
121 | blargg_err_t Sgc_load_mem( struct Sgc_Emu* this, const void* data, long size ); | ||
122 | |||
123 | static inline int clock_rate( struct Sgc_Emu* this ) { return this->header.rate ? 3546893 : 3579545; } | ||
124 | |||
125 | // 0x2000 bytes | ||
126 | static inline void set_coleco_bios( struct Sgc_Emu* this, void* p ) { this->coleco_bios = p; } | ||
127 | |||
128 | // Set output sample rate. Must be called only once before loading file. | ||
129 | blargg_err_t Sgc_set_sample_rate( struct Sgc_Emu* this, long sample_rate ); | ||
130 | |||
131 | // Start a track, where 0 is the first track. Also clears warning string. | ||
132 | blargg_err_t Sgc_start_track( struct Sgc_Emu* this, int track ); | ||
133 | |||
134 | // Generate 'count' samples info 'buf'. Output is in stereo. Any emulation | ||
135 | // errors set warning string, and major errors also end track. | ||
136 | blargg_err_t Sgc_play( struct Sgc_Emu* this, long count, sample_t* buf ); | ||
137 | |||
138 | // Track status/control | ||
139 | |||
140 | // Number of milliseconds (1000 msec = 1 second) played since beginning of track | ||
141 | long Track_tell( struct Sgc_Emu* this ); | ||
142 | |||
143 | // Seek to new time in track. Seeking backwards or far forward can take a while. | ||
144 | blargg_err_t Track_seek( struct Sgc_Emu* this, long msec ); | ||
145 | |||
146 | // Skip n samples | ||
147 | blargg_err_t Track_skip( struct Sgc_Emu* this, long n ); | ||
148 | |||
149 | // Set start time and length of track fade out. Once fade ends track_ended() returns | ||
150 | // true. Fade time can be changed while track is playing. | ||
151 | void Track_set_fade( struct Sgc_Emu* this, long start_msec, long length_msec ); | ||
152 | |||
153 | // Get track length in milliseconds | ||
154 | static inline long Track_get_length( struct Sgc_Emu* this, int n ) | ||
155 | { | ||
156 | long length = 120 * 1000; /* 2 minutes */ | ||
157 | if ( (this->m3u.size > 0) && (n < this->m3u.size) ) { | ||
158 | struct entry_t* entry = &this->m3u.entries [n]; | ||
159 | length = entry->length; | ||
160 | } | ||
161 | |||
162 | return length; | ||
163 | } | ||
164 | |||
165 | // Sound customization | ||
166 | |||
167 | // Adjust song tempo, where 1.0 = normal, 0.5 = half speed, 2.0 = double speed. | ||
168 | // Track length as returned by track_info() assumes a tempo of 1.0. | ||
169 | void Sound_set_tempo( struct Sgc_Emu* this, double t ); | ||
170 | |||
171 | // Mute/unmute voice i, where voice 0 is first voice | ||
172 | void Sound_mute_voice( struct Sgc_Emu* this, int index, bool mute ); | ||
173 | |||
174 | // Set muting state of all voices at once using a bit mask, where -1 mutes them all, | ||
175 | // 0 unmutes them all, 0x01 mutes just the first voice, etc. | ||
176 | void Sound_mute_voices( struct Sgc_Emu* this, int mask ); | ||
177 | |||
178 | // Change overall output amplitude, where 1.0 results in minimal clamping. | ||
179 | // Must be called before set_sample_rate(). | ||
180 | static inline void Sound_set_gain( struct Sgc_Emu* this, double g ) | ||
181 | { | ||
182 | assert( !this->sample_rate ); // you must set gain before setting sample rate | ||
183 | this->gain = g; | ||
184 | } | ||
185 | |||
186 | // True if Master System or Game Gear | ||
187 | static inline bool sega_mapping( struct Sgc_Emu* this ) | ||
188 | { | ||
189 | return this->header.system <= 1; | ||
190 | } | ||
191 | |||
192 | // Emulation (You shouldn't touch these) | ||
193 | |||
194 | bool run_cpu( struct Sgc_Emu* this, cpu_time_t end_time ) ICODE_ATTR; | ||
195 | void cpu_out( struct Sgc_Emu* this, cpu_time_t time, addr_t addr, int data ) ICODE_ATTR; | ||
196 | void cpu_write( struct Sgc_Emu* this, addr_t addr, int data ) ICODE_ATTR; | ||
197 | void jsr( struct Sgc_Emu* this, byte addr [2] ) ICODE_ATTR; | ||
198 | |||
199 | #endif | ||