X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=Pico%2Fsound%2Fym2612.c;h=754f496995a737dc71b5c97930adc053e490dbd6;hb=7969166ef66a8623cb4d8c609eb6e67314aefd79;hp=56e53127d07017c8811f48f2564bb1c9eef526dd;hpb=cc68a136aa179a5f32fe40208371eb9c2b0aadae;p=picodrive.git

diff --git a/Pico/sound/ym2612.c b/Pico/sound/ym2612.c
index 56e5312..754f496 100644
--- a/Pico/sound/ym2612.c
+++ b/Pico/sound/ym2612.c
@@ -1,5 +1,5 @@
 /*
-** This is a bunch of remains of original fm.c from MAME project. All stuff 
+** This is a bunch of remains of original fm.c from MAME project. All stuff
 ** unrelated to ym2612 was removed, multiple chip support was removed,
 ** some parts of code were slightly rewritten and tied to the emulator.
 **
@@ -120,11 +120,12 @@ static YM2612 ym2612;
 
 #else
 extern YM2612 *ym2612_940;
-extern int *mix_buffer;
 #define ym2612 (*ym2612_940)
 
 #endif
 
+void memset32(int *dest, int c, int count);
+
 
 #ifndef __GNUC__
 #pragma warning (disable:4100) // unreferenced formal parameter
@@ -841,7 +842,7 @@ typedef struct
 	UINT32 eg_timer;
 	UINT32 eg_timer_add;
 	UINT32 pack;     // 4c: stereo, lastchan, disabled, lfo_enabled | pan_r, pan_l, ams[2] | AMmasks[4] | FB[4] | lfo_ampm[16]
-	UINT32 algo;     /* 50 */
+	UINT32 algo;     /* 50: algo[3], was_update */
 	INT32  op1_out;
 } chan_rend_context;
 
@@ -1077,6 +1078,7 @@ static void chan_render_loop(chan_rend_context *ct, int *buffer, int length)
 			} else {
 				buffer[scounter] += smp;
 			}
+			ct->algo = 8; // algo is only used in asm, here only bit3 is used
 		}
 
 		/* update phase counters AFTER output calculations */
@@ -1091,7 +1093,7 @@ void chan_render_loop(chan_rend_context *ct, int *buffer, unsigned short length)
 #endif
 
 
-static void chan_render(int *buffer, int length, FM_CH *CH, UINT32 flags) // flags: stereo, lastchan, disabled, ?, pan_r, pan_l
+static int chan_render(int *buffer, int length, FM_CH *CH, UINT32 flags) // flags: stereo, lastchan, disabled, ?, pan_r, pan_l
 {
 	chan_rend_context ct;
 
@@ -1193,6 +1195,8 @@ static void chan_render(int *buffer, int length, FM_CH *CH, UINT32 flags) // fla
 	CH->SLOT[SLOT3].phase = ct.phase3;
 	CH->SLOT[SLOT4].phase = ct.phase4;
 	CH->mem_value = ct.mem;
+
+	return (ct.algo & 8) >> 3; // had output
 }
 
 /* update phase increment and envelope generator */
@@ -1584,13 +1588,13 @@ INT32 *ym2612_dacout;
 
 
 /* Generate samples for YM2612 */
-void YM2612UpdateOne_(short *buffer, int length, int stereo)
+int YM2612UpdateOne_(int *buffer, int length, int stereo, int is_buf_empty)
 {
 	int pan;
-#ifndef EXTERNAL_YM2612
-	int i;
-	static int *mix_buffer = 0, mix_buffer_length = 0;
-#endif
+	int active_chs = 0;
+
+	// if !is_buf_empty, it means it has valid samples to mix with, else it may contain trash
+	if (is_buf_empty) memset32(buffer, 0, length<<stereo);
 
 	/* refresh PG and EG */
 	refresh_fc_eg_chan( &ym2612.CH[0] );
@@ -1613,44 +1617,16 @@ void YM2612UpdateOne_(short *buffer, int length, int stereo)
 	pan = ym2612.OPN.pan;
 	if (stereo) stereo = 1;
 
-#ifndef EXTERNAL_YM2612
-	if (mix_buffer_length < length) {
-		mix_buffer = realloc(mix_buffer, length*4<<stereo); // FIXME: need to free this at some point
-		if (!mix_buffer) return;
-		mix_buffer_length = length;
-	}
-#endif
-	memset(mix_buffer, 0, length*4<<stereo);
+	/* mix to 32bit dest */
+	// flags: stereo, lastchan, disabled, ?, pan_r, pan_l
+	active_chs |= chan_render(buffer, length, &ym2612.CH[0], stereo|((pan&0x003)<<4)) << 0;
+	active_chs |= chan_render(buffer, length, &ym2612.CH[1], stereo|((pan&0x00c)<<2)) << 1;
+	active_chs |= chan_render(buffer, length, &ym2612.CH[2], stereo|((pan&0x030)   )) << 2;
+	active_chs |= chan_render(buffer, length, &ym2612.CH[3], stereo|((pan&0x0c0)>>2)) << 3;
+	active_chs |= chan_render(buffer, length, &ym2612.CH[4], stereo|((pan&0x300)>>4)) << 4;
+	active_chs |= chan_render(buffer, length, &ym2612.CH[5], stereo|((pan&0xc00)>>6)|(ym2612.dacen<<2)|2) << 5;
 
-	/* mix to 32bit temporary buffer */
-	chan_render(mix_buffer, length, &ym2612.CH[0], stereo|((pan&0x003)<<4)); // flags: stereo, lastchan, disabled, ?, pan_r, pan_l
-	chan_render(mix_buffer, length, &ym2612.CH[1], stereo|((pan&0x00c)<<2));
-	chan_render(mix_buffer, length, &ym2612.CH[2], stereo|((pan&0x030)   ));
-	chan_render(mix_buffer, length, &ym2612.CH[3], stereo|((pan&0x0c0)>>2));
-	chan_render(mix_buffer, length, &ym2612.CH[4], stereo|((pan&0x300)>>4));
-	chan_render(mix_buffer, length, &ym2612.CH[5], stereo|((pan&0xc00)>>6)|(ym2612.dacen<<2)|2);
-
-#ifndef EXTERNAL_YM2612
-	/* limit and mix to output buffer */
-	if (stereo) {
-		int *mb = mix_buffer;
-		for (i = length; i > 0; i--) {
-			int l, r;
-			l = r = *buffer;
-			l += *mb++, r += *mb++;
-			Limit( l, MAXOUT, MINOUT );
-			Limit( r, MAXOUT, MINOUT );
-			*buffer++ = l; *buffer++ = r;
-		}
-	} else {
-		for (i = 0; i < length; i++) {
-			int l = mix_buffer[i];
-			l += buffer[i];
-			Limit( l, MAXOUT, MINOUT );
-			buffer[i] = l;
-		}
-	}
-#endif
+	return active_chs; // 1 if buffer updated
 }
 
 
@@ -1726,7 +1702,9 @@ int YM2612Write_(unsigned int a, unsigned int v)
 		}
 
 		addr = ym2612.OPN.ST.address;
+#ifndef EXTERNAL_YM2612
 		ym2612.REGS[addr] = v;
+#endif
 
 		switch( addr & 0xf0 )
 		{
@@ -1824,7 +1802,9 @@ int YM2612Write_(unsigned int a, unsigned int v)
 		}
 
 		addr = ym2612.OPN.ST.address | 0x100;
+#ifndef EXTERNAL_YM2612
 		ym2612.REGS[addr] = v;
+#endif
 
 		ret = OPNWriteReg(addr, v);
 		break;
@@ -1893,7 +1873,10 @@ void YM2612PicoStateLoad_(void)
 }
 
 
+#ifndef EXTERNAL_YM2612
 void *YM2612GetRegs(void)
 {
 	return ym2612.REGS;
 }
+#endif
+