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diff --git a/lib/rbcodec/codecs/libgme/gbs_emu.h b/lib/rbcodec/codecs/libgme/gbs_emu.h
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1// Nintendo Game Boy GBS music file emulator
2
3// Game_Music_Emu 0.5.2
4#ifndef GBS_EMU_H
5#define GBS_EMU_H
6
7#include "rom_data.h"
8#include "multi_buffer.h"
9#include "gb_apu.h"
10#include "gb_cpu.h"
11#include "m3u_playlist.h"
12#include "track_filter.h"
13
14enum { joypad_addr = 0xFF00 };
15enum { ram_addr = 0xA000 };
16enum { hi_page = 0xFF00 - ram_addr };
17enum { io_base = 0xFF00 };
18
19// Selects which sound hardware to use. AGB hardware is cleaner than the
20// others. Doesn't take effect until next start_track().
21enum sound_t {
22 sound_dmg = mode_dmg, // Game Boy monochrome
23 sound_cgb = mode_cgb, // Game Boy Color
24 sound_agb = mode_agb, // Game Boy Advance
25 sound_gbs // Use DMG/CGB based on GBS (default)
26};
27
28// GBS file header
29enum { header_size = 112 };
30struct header_t
31{
32 char tag [3];
33 byte vers;
34 byte track_count;
35 byte first_track;
36 byte load_addr [2];
37 byte init_addr [2];
38 byte play_addr [2];
39 byte stack_ptr [2];
40 byte timer_modulo;
41 byte timer_mode;
42 char game [32];
43 char author [32];
44 char copyright [32];
45};
46
47struct Gbs_Emu {
48 enum sound_t sound_hardware;
49
50 int tempo;
51
52 // timer
53 blip_time_t cpu_time;
54 blip_time_t end_time;
55 blip_time_t play_period;
56 blip_time_t next_play;
57
58 // Sound
59 int clock_rate_;
60 int sample_rate_;
61 unsigned buf_changed_count;
62 int voice_count_;
63 int const* voice_types_;
64 int mute_mask_;
65 int gain_;
66 int tempo_;
67
68 // track-specific
69 byte track_count;
70 int current_track_;
71
72 // Larger items at the end
73 // Header for currently loaded file
74 struct header_t header;
75
76 // M3u Playlist
77 struct M3u_Playlist m3u;
78
79 struct setup_t tfilter;
80 struct Track_Filter track_filter;
81
82 struct Gb_Apu apu;
83 struct Gb_Cpu cpu;
84 struct Multi_Buffer stereo_buf;
85
86 // rom & ram
87 struct Rom_Data rom;
88 byte ram [0x4000 + 0x2000 + cpu_padding];
89};
90
91
92// Basic functionality
93// Initializes Gbs_Emu structure
94void Gbs_init( struct Gbs_Emu* this );
95
96// Stops (clear) Gbs_Emu structure
97void Gbs_stop( struct Gbs_Emu* this );
98
99// Loads a file from memory
100blargg_err_t Gbs_load_mem( struct Gbs_Emu* this, void* data, long size );
101
102// Set output sample rate. Must be called only once before loading file.
103blargg_err_t Gbs_set_sample_rate( struct Gbs_Emu* this, int sample_rate );
104
105// Start a track, where 0 is the first track. Also clears warning string.
106blargg_err_t Gbs_start_track( struct Gbs_Emu* this, int );
107
108// Generate 'count' samples info 'buf'. Output is in stereo. Any emulation
109// errors set warning string, and major errors also end track.
110blargg_err_t Gbs_play( struct Gbs_Emu* this, int count, sample_t* buf );
111
112// Track status/control
113// Number of milliseconds (1000 msec = 1 second) played since beginning of track
114int Track_tell( struct Gbs_Emu* this );
115
116// Seek to new time in track. Seeking backwards or far forward can take a while.
117blargg_err_t Track_seek( struct Gbs_Emu* this, int msec );
118
119// Skip n samples
120blargg_err_t Track_skip( struct Gbs_Emu* this, int n );
121
122// Set start time and length of track fade out. Once fade ends track_ended() returns
123// true. Fade time can be changed while track is playing.
124void Track_set_fade( struct Gbs_Emu* this, int start_msec, int length_msec );
125
126// True if a track has reached its end
127static inline bool Track_ended( struct Gbs_Emu* this )
128{
129 return track_ended( &this->track_filter );
130}
131
132// Disables automatic end-of-track detection and skipping of silence at beginning
133static inline void Track_ignore_silence( struct Gbs_Emu* this, bool disable )
134{
135 this->track_filter.silence_ignored_ = disable;
136}
137
138// Get track length in milliseconds
139static inline int Track_get_length( struct Gbs_Emu* this, int n )
140{
141 int length = 120 * 1000; /* 2 minutes */
142 if ( (this->m3u.size > 0) && (n < this->m3u.size) ) {
143 struct entry_t* entry = &this->m3u.entries [n];
144 length = entry->length;
145 }
146
147 return length;
148}
149
150
151// Sound customization
152// Adjust song tempo, where 1.0 = normal, 0.5 = half speed, 2.0 = double speed.
153// Track length as returned by track_info() assumes a tempo of 1.0.
154void Sound_set_tempo( struct Gbs_Emu* this, int );
155
156// Mute/unmute voice i, where voice 0 is first voice
157void Sound_mute_voice( struct Gbs_Emu* this, int index, bool mute );
158
159// Set muting state of all voices at once using a bit mask, where -1 mutes them all,
160// 0 unmutes them all, 0x01 mutes just the first voice, etc.
161void Sound_mute_voices( struct Gbs_Emu* this, int mask );
162
163// Change overall output amplitude, where 1.0 results in minimal clamping.
164// Must be called before set_sample_rate().
165static inline void Sound_set_gain( struct Gbs_Emu* this, int g )
166{
167 assert( !this->sample_rate_ ); // you must set gain before setting sample rate
168 this->gain_ = g;
169}
170
171// Emulation (You shouldn't touch these)
172
173blargg_err_t run_clocks( struct Gbs_Emu* this, blip_time_t duration );
174void set_bank( struct Gbs_Emu* this, int );
175void update_timer( struct Gbs_Emu* this );
176
177// Runs CPU until time becomes >= 0
178void run_cpu( struct Gbs_Emu* this );
179
180// Reads/writes memory and I/O
181int read_mem( struct Gbs_Emu* this, addr_t addr );
182void write_mem( struct Gbs_Emu* this, addr_t addr, int data );
183
184// Current time
185static inline blip_time_t Time( struct Gbs_Emu* this )
186{
187 return Cpu_time( &this->cpu ) + this->end_time;
188}
189
190void jsr_then_stop( struct Gbs_Emu* this, byte const [] );
191
192#endif