git.maemo.org Git - drnoksnes/blob - platform/sdl.cpp

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <sys/time.h>
   4 #include <time.h>
   5 #include <SDL.h>
   6
   7 #include "platform.h"
   8 #include "snes9x.h"
   9 #include "gfx.h"
  10 #include "display.h"
  11 #include "memmap.h"
  12 #include "soundux.h"
  13 #include "hacks.h"
  14
  15 #define kPollEveryNFrames       4               //Poll input only every this many frames
  16
  17 #define TRACE printf("trace: %s:%s\n", __FILE__, __func__);
  18 #define DIE(format, ...) do { \
  19                 fprintf(stderr, "Died at %s:%d: ", __FILE__, __LINE__ ); \
  20                 fprintf(stderr, format "\n", ## __VA_ARGS__); \
  21                 abort(); \
  22         } while (0);
  23
  24 void S9xMessage(int type, int number, const char * message)
  25 {
  26         printf("%s\n", message);
  27 }
  28
  29 void S9xLoadSDD1Data()
  30 {TRACE
  31         Settings.SDD1Pack=FALSE;
  32 }
  33
  34 static void S9xInit()
  35 {
  36         if (!Memory.Init () || !S9xInitAPU())
  37          DIE("Memory or APU failed");
  38
  39         if (!S9xInitSound ())
  40                 DIE("Sound failed");
  41         S9xSetSoundMute (TRUE);
  42
  43         // TODO: PAL/NTSC something better than this
  44         Settings.PAL = Settings.ForcePAL;
  45
  46         Settings.FrameTime = Settings.PAL?Settings.FrameTimePAL:Settings.FrameTimeNTSC;
  47         Memory.ROMFramesPerSecond = Settings.PAL?50:60;
  48
  49         IPPU.RenderThisFrame = TRUE;
  50 }
  51
  52 static void loadRom()
  53 {
  54         const char * file = S9xGetFilename(".smc");
  55
  56         printf("ROM: %s\n", file);
  57
  58         if (!Memory.LoadROM(file))
  59                 DIE("Loading ROM failed");
  60
  61         file = S9xGetFilename(".srm");
  62         printf("SRAM: %s\n", file);
  63         Memory.LoadSRAM(file);
  64 }
  65
  66 /* This comes nearly straight from snes9x */
  67 static void frameSync() {
  68         static struct timeval next1 = {0, 0};
  69         struct timeval now;
  70
  71         if (Settings.TurboMode)
  72         {
  73                 if(Settings.SkipFrames == AUTO_FRAMERATE ||
  74                         ++IPPU.FrameSkip >= Settings.SkipFrames)
  75                 {
  76                         IPPU.FrameSkip = 0;
  77                         IPPU.SkippedFrames = 0;
  78                         IPPU.RenderThisFrame = TRUE;
  79                 }
  80                 else
  81                 {
  82                         ++IPPU.SkippedFrames;
  83                         IPPU.RenderThisFrame = FALSE;
  84                 }
  85                 return;
  86         }
  87
  88         /* Normal mode */
  89
  90         while (gettimeofday(&now, 0) < 0);
  91
  92         /* If there is no known "next" frame, initialize it now */
  93         if (next1.tv_sec == 0) { next1 = now; ++next1.tv_usec; }
  94
  95     /* If we're on AUTO_FRAMERATE, we'll display frames always
  96      * only if there's excess time.
  97      * Otherwise we'll display the defined amount of frames.
  98      */
  99     unsigned limit = Settings.SkipFrames == AUTO_FRAMERATE
 100                      ? (timercmp(&next1, &now, <) ? 10 : 1)
 101                      : Settings.SkipFrames;
 102
 103     IPPU.RenderThisFrame = ++IPPU.SkippedFrames >= limit;
 104     if(IPPU.RenderThisFrame)
 105     {
 106         IPPU.SkippedFrames = 0;
 107     }
 108     else
 109     {
 110         /* If we were behind the schedule, check how much it is */
 111         if(timercmp(&next1, &now, <))
 112         {
 113             unsigned lag =
 114                 (now.tv_sec - next1.tv_sec) * 1000000
 115                + now.tv_usec - next1.tv_usec;
 116             if(lag >= 500000)
 117             {
 118                 /* More than a half-second behind means probably
 119                  * pause. The next line prevents the magic
 120                  * fast-forward effect.
 121                  */
 122                 next1 = now;
 123             }
 124         }
 125     }
 126
 127     /* Delay until we're completed this frame */
 128
 129     /* Can't use setitimer because the sound code already could
 130      * be using it. We don't actually need it either.
 131      */
 132
 133     while(timercmp(&next1, &now, >))
 134     {
 135         /* If we're ahead of time, sleep a while */
 136         unsigned timeleft =
 137             (next1.tv_sec - now.tv_sec) * 1000000
 138            + next1.tv_usec - now.tv_usec;
 139
 140         usleep(timeleft);
 141
 142         // XXX : CHECK_SOUND(); S9xProcessEvents(FALSE);
 143
 144         while (gettimeofday(&now, 0) < 0);
 145         /* Continue with a while-loop because usleep()
 146          * could be interrupted by a signal
 147          */
 148     }
 149
 150     /* Calculate the timestamp of the next frame. */
 151     next1.tv_usec += Settings.FrameTime;
 152     if (next1.tv_usec >= 1000000)
 153     {
 154         next1.tv_sec += next1.tv_usec / 1000000;
 155         next1.tv_usec %= 1000000;
 156     }
 157 }
 158
 159 /** Wraps s9xProcessEvents, taking care of kPollEveryNFrames */
 160 static inline void pollEvents() {
 161         static int frames = 0;
 162
 163         if (++frames > kPollEveryNFrames) {
 164                 S9xProcessEvents(FALSE);
 165                 frames = 0;
 166         }
 167 }
 168
 169 int main(int argc, const char ** argv) {
 170         // Initialise SDL
 171         if (SDL_Init(0) < 0)
 172                 DIE("SDL_Init: %s", SDL_GetError());
 173
 174         // Configure snes9x
 175         S9xLoadConfig(argc, argv);
 176
 177         // S9x initialization
 178         S9xInitDisplay(argc, argv);
 179         S9xInitAudioOutput();
 180         S9xInitInputDevices();
 181         S9xInit();
 182         S9xReset();
 183
 184         // Load rom and related files
 185         loadRom();
 186
 187         // Late initialization
 188         sprintf(String, "DrNokSnes - %s", Memory.ROMName);
 189         S9xSetTitle(String);
 190         S9xHacksLoadFile(Config.hacksFile[0] ? Config.hacksFile : 0);
 191         if (!S9xGraphicsInit())
 192          DIE("S9xGraphicsInit failed");
 193         S9xAudioOutputEnable(true);
 194
 195         do {
 196                 frameSync();                    // May block, or set frameskip to true.
 197                 S9xMainLoop();                  // Does CPU things, renders if needed.
 198                 pollEvents();
 199         } while (!Config.quitting);
 200
 201         // Deinitialization
 202         S9xAudioOutputEnable(false);
 203         S9xDeinitAudioOutput();
 204         S9xDeinitDisplay();
 205         S9xGraphicsDeinit();
 206
 207         SDL_Quit();
 208
 209         return 0;
 210 }
 211
 212 void S9xDoAction(unsigned char action)
 213 {
 214         if (action & kActionQuit)
 215                 Config.quitting = true;
 216
 217         if (action & kActionToggleFullscreen)
 218                 S9xVideoToggleFullscreen();
 219 }
 220