1 files changed, 289 insertions, 0 deletions
diff --git a/plugins/gme/game-music-emu-0.6.0/gme/Gbs_Emu.cpp b/plugins/gme/game-music-emu-0.6.0/gme/Gbs_Emu.cpp
new file mode 100644
index 00000000..c3a0153b
--- /dev/null
+++ b/plugins/gme/game-music-emu-0.6.0/gme/Gbs_Emu.cpp
@@ -0,0 +1,289 @@
+// Game_Music_Emu 0.5.5. http://www.slack.net/~ant/
+
+#include "Gbs_Emu.h"
+
+#include "blargg_endian.h"
+#include <string.h>
+
+/* Copyright (C) 2003-2006 Shay Green. This module is free software; you
+can redistribute it and/or modify it under the terms of the GNU Lesser
+General Public License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version. This
+module 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 Lesser General Public License for more
+details. You should have received a copy of the GNU Lesser General Public
+License along with this module; if not, write to the Free Software Foundation,
+Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
+
+#include "blargg_source.h"
+
+Gbs_Emu::equalizer_t const Gbs_Emu::handheld_eq   = { -47.0, 2000 };
+Gbs_Emu::equalizer_t const Gbs_Emu::headphones_eq = {   0.0,  300 };
+
+Gbs_Emu::Gbs_Emu()
+{
+	set_type( gme_gbs_type );
+	
+	static const char* const names [Gb_Apu::osc_count] = {
+		"Square 1", "Square 2", "Wave", "Noise"
+	};
+	set_voice_names( names );
+	
+	static int const types [Gb_Apu::osc_count] = {
+		wave_type | 1, wave_type | 2, wave_type | 0, mixed_type | 0
+	};
+	set_voice_types( types );
+	
+	set_silence_lookahead( 6 );
+	set_max_initial_silence( 21 );
+	set_gain( 1.2 );
+	
+	static equalizer_t const eq = { -1.0, 120 };
+	set_equalizer( eq );
+}
+
+Gbs_Emu::~Gbs_Emu() { }
+
+void Gbs_Emu::unload()
+{
+	rom.clear();
+	Music_Emu::unload();
+}
+
+// Track info
+
+static void copy_gbs_fields( Gbs_Emu::header_t const& h, track_info_t* out )
+{
+	GME_COPY_FIELD( h, out, game );
+	GME_COPY_FIELD( h, out, author );
+	GME_COPY_FIELD( h, out, copyright );
+}
+
+blargg_err_t Gbs_Emu::track_info_( track_info_t* out, int ) const
+{
+	copy_gbs_fields( header_, out );
+	return 0;
+}
+
+static blargg_err_t check_gbs_header( void const* header )
+{
+	if ( memcmp( header, "GBS", 3 ) )
+		return gme_wrong_file_type;
+	return 0;
+}
+
+struct Gbs_File : Gme_Info_
+{
+	Gbs_Emu::header_t h;
+	
+	Gbs_File() { set_type( gme_gbs_type ); }
+	
+	blargg_err_t load_( Data_Reader& in )
+	{
+		blargg_err_t err = in.read( &h, Gbs_Emu::header_size );
+		if ( err )
+			return (err == in.eof_error ? gme_wrong_file_type : err);
+		
+		set_track_count( h.track_count );
+		return check_gbs_header( &h );
+	}
+	
+	blargg_err_t track_info_( track_info_t* out, int ) const
+	{
+		copy_gbs_fields( h, out );
+		return 0;
+	}
+};
+
+static Music_Emu* new_gbs_emu () { return BLARGG_NEW Gbs_Emu ; }
+static Music_Emu* new_gbs_file() { return BLARGG_NEW Gbs_File; }
+
+static gme_type_t_ const gme_gbs_type_ = { "Game Boy", 0, &new_gbs_emu, &new_gbs_file, "GBS", 1 };
+gme_type_t const gme_gbs_type = &gme_gbs_type_;
+
+// Setup
+
+blargg_err_t Gbs_Emu::load_( Data_Reader& in )
+{
+	assert( offsetof (header_t,copyright [32]) == header_size );
+	RETURN_ERR( rom.load( in, header_size, &header_, 0 ) );
+	
+	set_track_count( header_.track_count );
+	RETURN_ERR( check_gbs_header( &header_ ) );
+	
+	if ( header_.vers != 1 )
+		set_warning( "Unknown file version" );
+	
+	if ( header_.timer_mode & 0x78 )
+		set_warning( "Invalid timer mode" );
+	
+	unsigned load_addr = get_le16( header_.load_addr );
+	if ( (header_.load_addr [1] | header_.init_addr [1] | header_.play_addr [1]) > 0x7F ||
+			load_addr < 0x400 )
+		set_warning( "Invalid load/init/play address" );
+	
+	set_voice_count( Gb_Apu::osc_count );
+	
+	apu.volume( gain() );
+	
+	return setup_buffer( 4194304 );
+}
+
+void Gbs_Emu::update_eq( blip_eq_t const& eq )
+{
+	apu.treble_eq( eq );
+}
+
+void Gbs_Emu::set_voice( int i, Blip_Buffer* c, Blip_Buffer* l, Blip_Buffer* r )
+{
+	apu.osc_output( i, c, l, r );
+}
+
+// Emulation
+
+// see gb_cpu_io.h for read/write functions
+
+void Gbs_Emu::set_bank( int n )
+{
+	blargg_long addr = rom.mask_addr( n * (blargg_long) bank_size );
+	if ( addr == 0 && rom.size() > bank_size )
+	{
+		// TODO: what is the correct behavior? Current Game & Watch Gallery
+		// rip requires that this have no effect or set to bank 1.
+		//debug_printf( "Selected ROM bank 0\n" );
+		return;
+		//n = 1;
+	}
+	cpu::map_code( bank_size, bank_size, rom.at_addr( addr ) );
+}
+
+void Gbs_Emu::update_timer()
+{
+	if ( header_.timer_mode & 0x04 )
+	{
+		static byte const rates [4] = { 10, 4, 6, 8 };
+		int shift = rates [ram [hi_page + 7] & 3] - (header_.timer_mode >> 7);
+		play_period = (256L - ram [hi_page + 6]) << shift;
+	}
+	else
+	{
+		play_period = 70224; // 59.73 Hz
+	}
+	if ( tempo() != 1.0 )
+		play_period = blip_time_t (play_period / tempo());
+}
+
+static BOOST::uint8_t const sound_data [Gb_Apu::register_count] = {
+	0x80, 0xBF, 0x00, 0x00, 0xBF, // square 1
+	0x00, 0x3F, 0x00, 0x00, 0xBF, // square 2
+	0x7F, 0xFF, 0x9F, 0x00, 0xBF, // wave
+	0x00, 0xFF, 0x00, 0x00, 0xBF, // noise
+	0x77, 0xF3, 0xF1, // vin/volume, status, power mode
+	0, 0, 0, 0, 0, 0, 0, 0, 0, // unused
+	0xAC, 0xDD, 0xDA, 0x48, 0x36, 0x02, 0xCF, 0x16, // waveform data
+	0x2C, 0x04, 0xE5, 0x2C, 0xAC, 0xDD, 0xDA, 0x48
+};
+
+void Gbs_Emu::cpu_jsr( gb_addr_t addr )
+{
+	check( cpu::r.sp == get_le16( header_.stack_ptr ) );
+	cpu::r.pc = addr;
+	cpu_write( --cpu::r.sp, idle_addr >> 8 );
+	cpu_write( --cpu::r.sp, idle_addr&0xFF );
+}
+
+void Gbs_Emu::set_tempo_( double t )
+{
+	apu.set_tempo( t );
+	update_timer();
+}
+
+blargg_err_t Gbs_Emu::start_track_( int track )
+{
+	RETURN_ERR( Classic_Emu::start_track_( track ) );
+	
+	memset( ram, 0, 0x4000 );
+	memset( ram + 0x4000, 0xFF, 0x1F80 );
+	memset( ram + 0x5F80, 0, sizeof ram - 0x5F80 );
+	ram [hi_page] = 0; // joypad reads back as 0
+	
+	apu.reset();
+	for ( int i = 0; i < (int) sizeof sound_data; i++ )
+		apu.write_register( 0, i + apu.start_addr, sound_data [i] );
+	
+	unsigned load_addr = get_le16( header_.load_addr );
+	rom.set_addr( load_addr );
+	cpu::rst_base = load_addr;
+	
+	cpu::reset( rom.unmapped() );
+	
+	cpu::map_code( ram_addr, 0x10000 - ram_addr, ram );
+	cpu::map_code( 0, bank_size, rom.at_addr( 0 ) );
+	set_bank( rom.size() > bank_size );
+	
+	ram [hi_page + 6] = header_.timer_modulo;
+	ram [hi_page + 7] = header_.timer_mode;
+	update_timer();
+	next_play = play_period;
+	
+	cpu::r.a  = track;
+	cpu::r.pc = idle_addr;
+	cpu::r.sp = get_le16( header_.stack_ptr );
+	cpu_time  = 0;
+	cpu_jsr( get_le16( header_.init_addr ) );
+	
+	return 0;
+}
+
+blargg_err_t Gbs_Emu::run_clocks( blip_time_t& duration, int )
+{
+	cpu_time = 0;
+	while ( cpu_time < duration )
+	{
+		long count = duration - cpu_time;
+		cpu_time = duration;
+		bool result = cpu::run( count );
+		cpu_time -= cpu::remain();
+		
+		if ( result )
+		{
+			if ( cpu::r.pc == idle_addr )
+			{
+				if ( next_play > duration )
+				{
+					cpu_time = duration;
+					break;
+				}
+				
+				if ( cpu_time < next_play )
+					cpu_time = next_play;
+				next_play += play_period;
+				cpu_jsr( get_le16( header_.play_addr ) );
+				GME_FRAME_HOOK( this );
+				// TODO: handle timer rates different than 60 Hz
+			}
+			else if ( cpu::r.pc > 0xFFFF )
+			{
+				debug_printf( "PC wrapped around\n" );
+				cpu::r.pc &= 0xFFFF;
+			}
+			else
+			{
+				set_warning( "Emulation error (illegal/unsupported instruction)" );
+				debug_printf( "Bad opcode $%.2x at $%.4x\n",
+						(int) *cpu::get_code( cpu::r.pc ), (int) cpu::r.pc );
+				cpu::r.pc = (cpu::r.pc + 1) & 0xFFFF;
+				cpu_time += 6;
+			}
+		}
+	}
+	
+	duration = cpu_time;
+	next_play -= cpu_time;
+	if ( next_play < 0 ) // could go negative if routine is taking too long to return
+		next_play = 0;
+	apu.end_frame( cpu_time );
+	
+	return 0;
+}