clean up dac code a bit

[picodrive.git] / pico / sound / sound.c

diff --git a/pico/sound/sound.c b/pico/sound/sound.c
index 69c1be0..8f88dd7 100644 (file)
--- a/pico/sound/sound.c
+++ b/pico/sound/sound.c
@@ -14,15 +14,13 @@
 #include "../cd/cue.h"\r
 #include "mix.h"\r
 \r
-#define SIMPLE_WRITE_SOUND 0\r
-\r
 void (*PsndMix_32_to_16l)(short *dest, int *src, int count) = mix_32_to_16l_stereo;\r
 \r
 // master int buffer to mix to\r
 static int PsndBuffer[2*(44100+100)/50];\r
 \r
 // dac\r
-static unsigned short dac_info[312+4]; // pppppppp ppppllll, p - pos in buff, l - length to write for this sample\r
+static unsigned short dac_info[312+4]; // pos in sample buffer\r
 \r
 // cdda output buffer\r
 short cdda_out_buffer[2*1152];\r
@@ -34,6 +32,7 @@ int PsndLen_exc_add=0; // this is for non-integer sample counts per line, eg. 22
 int PsndLen_exc_cnt=0;\r
 int PsndDacLine=0;\r
 short *PsndOut=NULL; // PCM data buffer\r
+static int PsndLen_use;\r
 \r
 // timers\r
 int timer_a_next_oflow, timer_a_step; // in z80 cycles\r
@@ -57,14 +56,12 @@ static void dac_recalculate(void)
     for(i=226; i != 225; i++)\r
     {\r
       if (i >= lines) i = 0;\r
-      len = 0;\r
       if(dac_cnt < 0) {\r
-        len=1;\r
         pos++;\r
         dac_cnt += lines;\r
       }\r
       dac_cnt -= PsndLen;\r
-      dac_info[i] = (pos<<4)|len;\r
+      dac_info[i] = pos;\r
     }\r
   }\r
   else\r
@@ -86,24 +83,12 @@ static void dac_recalculate(void)
           len++;\r
         }\r
       dac_cnt += PsndLen;\r
-      dac_info[i] = (pos<<4)|len;\r
-      pos+=len;\r
+      pos += len;\r
+      dac_info[i] = pos;\r
     }\r
-    // last sample\r
-    for(len = 0, i = pos; i < PsndLen; i++) len++;\r
-    if (PsndLen_exc_add) len++;\r
-    dac_info[224] = (pos<<4)|len;\r
   }\r
-  mid = (dac_info[lines-1] & 0xfff0) + ((dac_info[lines-1] & 0xf) << 4);\r
   for (i = lines; i < sizeof(dac_info) / sizeof(dac_info[0]); i++)\r
-    dac_info[i] = mid;\r
-  //for(i=len=0; i < lines; i++) {\r
-  //  printf("%03i : %03i : %i\n", i, dac_info[i]>>4, dac_info[i]&0xf);\r
-  //  len+=dac_info[i]&0xf;\r
-  //}\r
-  //printf("rate is %i, len %f\n", PsndRate, (double)PsndRate/(Pico.m.pal ? 50.0 : 60.0));\r
-  //printf("len total: %i, last pos: %i\n", len, pos);\r
-  //exit(8);\r
+    dac_info[i] = dac_info[0];\r
 }\r
 \r
 \r
@@ -163,6 +148,21 @@ void PsndRerate(int preserve_state)
 }\r
 \r
 \r
+PICO_INTERNAL void PsndStartFrame(void)\r
+{\r
+  // compensate for float part of PsndLen\r
+  PsndLen_use = PsndLen;\r
+  PsndLen_exc_cnt += PsndLen_exc_add;\r
+  if (PsndLen_exc_cnt >= 0x10000) {\r
+    PsndLen_exc_cnt -= 0x10000;\r
+    PsndLen_use++;\r
+  }\r
+\r
+  PsndDacLine = 0;\r
+  emustatus &= ~1;\r
+  dac_info[224] = PsndLen_use;\r
+}\r
+\r
 PICO_INTERNAL void PsndDoDAC(int line_to)\r
 {\r
   int pos, pos1, len;\r
@@ -172,12 +172,16 @@ PICO_INTERNAL void PsndDoDAC(int line_to)
   if (line_to >= 312)\r
     line_to = 311;\r
 \r
+  pos  = dac_info[line_from];\r
+  pos1 = dac_info[line_to + 1];\r
+  len = pos1 - pos;\r
+  if (len <= 0)\r
+    return;\r
+\r
   PsndDacLine = line_to + 1;\r
 \r
-  pos =dac_info[line_from]>>4;\r
-  pos1=dac_info[line_to];\r
-  len = ((pos1>>4)-pos) + (pos1&0xf);\r
-  if (!len) return;\r
+  if (!PsndOut)\r
+    return;\r
 \r
   if (PicoOpt & POPT_EN_STEREO) {\r
     short *d = PsndOut + pos*2;\r
@@ -260,17 +264,6 @@ static int PsndRender(int offset, int length)
 \r
   pprof_start(sound);\r
 \r
-#if !SIMPLE_WRITE_SOUND\r
-  if (offset == 0) { // should happen once per frame\r
-    // compensate for float part of PsndLen\r
-    PsndLen_exc_cnt += PsndLen_exc_add;\r
-    if (PsndLen_exc_cnt >= 0x10000) {\r
-      PsndLen_exc_cnt -= 0x10000;\r
-      length++;\r
-    }\r
-  }\r
-#endif\r
-\r
   // PSG\r
   if (PicoOpt & POPT_EN_PSG)\r
     SN76496Update(PsndOut+offset, length, stereo);\r
@@ -322,20 +315,16 @@ static int PsndRender(int offset, int length)
 // to be called on 224 or line_sample scanlines only\r
 PICO_INTERNAL void PsndGetSamples(int y)\r
 {\r
-#if SIMPLE_WRITE_SOUND\r
-  if (y != 224) return;\r
-  PsndRender(0, PsndLen);\r
-  if (PicoWriteSound)\r
-    PicoWriteSound(PsndLen * ((PicoOpt & POPT_EN_STEREO) ? 4 : 2));\r
-  PsndClear();\r
-#else\r
   static int curr_pos = 0;\r
 \r
+  if (ym2612.dacen && PsndDacLine < y)\r
+    PsndDoDAC(y - 1);\r
+\r
   if (y == 224)\r
   {\r
     if (emustatus & 2)\r
          curr_pos += PsndRender(curr_pos, PsndLen-PsndLen/2);\r
-    else curr_pos  = PsndRender(0, PsndLen);\r
+    else curr_pos  = PsndRender(0, PsndLen_use);\r
     if (emustatus & 1)\r
          emustatus |=  2;\r
     else emustatus &= ~2;\r
@@ -343,28 +332,20 @@ PICO_INTERNAL void PsndGetSamples(int y)
       PicoWriteSound(curr_pos * ((PicoOpt & POPT_EN_STEREO) ? 4 : 2));\r
     // clear sound buffer\r
     PsndClear();\r
+    PsndDacLine = 224;\r
+    dac_info[224] = 0;\r
   }\r
   else if (emustatus & 3) {\r
     emustatus|= 2;\r
     emustatus&=~1;\r
     curr_pos = PsndRender(0, PsndLen/2);\r
   }\r
-#endif\r
 }\r
 \r
 PICO_INTERNAL void PsndGetSamplesMS(void)\r
 {\r
   int stereo = (PicoOpt & 8) >> 3;\r
-  int length = PsndLen;\r
-\r
-#if !SIMPLE_WRITE_SOUND\r
-  // compensate for float part of PsndLen\r
-  PsndLen_exc_cnt += PsndLen_exc_add;\r
-  if (PsndLen_exc_cnt >= 0x10000) {\r
-    PsndLen_exc_cnt -= 0x10000;\r
-    length++;\r
-  }\r
-#endif\r
+  int length = PsndLen_use;\r
 \r
   // PSG\r
   if (PicoOpt & POPT_EN_PSG)\r
@@ -382,3 +363,4 @@ PICO_INTERNAL void PsndGetSamplesMS(void)
   PsndClear();\r
 }\r
 \r
+// vim:shiftwidth=2:ts=2:expandtab\r