glut_gamemode.c

mesa-6.5-minigui源码

/* Copyright (c) Mark J. Kilgard, 1998. */

/* This program is freely distributable without licensing fees
   and is provided without guarantee or warrantee expressed or
   implied. This program is -not- in the public domain. */

#ifdef __VMS
#include <GL/vms_x_fix.h>
#endif

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "glutint.h"

#ifndef _WIN32
#include <X11/Xlib.h>
#include <X11/Xatom.h>

/* SGI optimization introduced in IRIX 6.3 to avoid X server
   round trips for interning common X atoms. */
#if defined(_SGI_EXTRA_PREDEFINES) && !defined(NO_FAST_ATOMS)
#include <X11/SGIFastAtom.h>
#else
#define XSGIFastInternAtom(dpy,string,fast_name,how) XInternAtom(dpy,string,how)
#endif
#endif  /* not _WIN32 */

int __glutDisplaySettingsChanged = 0;
static DisplayMode *dmodes, *currentDm = NULL;
static int ndmodes = -1;
GLUTwindow *__glutGameModeWindow = NULL;

#ifdef TEST
static char *compstr[] =
{
  "none", "=", "!=", "<=", ">=", ">", "<", "~"
};
static char *capstr[] =
{
  "width", "height", "bpp", "hertz", "num"
};
#endif

void
__glutCloseDownGameMode(void)
{
  if (__glutDisplaySettingsChanged) {
#ifdef _WIN32
    /* Assumes that display settings have been changed, that
       is __glutDisplaySettingsChanged is true. */
    ChangeDisplaySettings(NULL, 0);
#endif
    __glutDisplaySettingsChanged = 0;
  }
  __glutGameModeWindow = NULL;
}

void GLUTAPIENTRY
glutLeaveGameMode(void)
{
  if (__glutGameModeWindow == NULL) {
    __glutWarning("not in game mode so cannot leave game mode");
    return;
  }
  __glutDestroyWindow(__glutGameModeWindow,
    __glutGameModeWindow);
  XFlush(__glutDisplay);
  __glutGameModeWindow = NULL;
}

#ifdef _WIN32

/* Same values as from MSDN's SetDisp.c example. */
#define MIN_WIDTH 400
#define MIN_FREQUENCY 60

static void
initGameModeSupport(void)
{
  DEVMODE dm;
  DWORD mode;
  int i;

  if (ndmodes >= 0) {
    /* ndmodes is initially -1 to indicate no
       dmodes allocated yet. */
    return;
  }

  /* Determine how many display modes there are. */
  ndmodes = 0;
  mode = 0;
  while (EnumDisplaySettings(NULL, mode, &dm)) {
    if (dm.dmPelsWidth >= MIN_WIDTH &&
      (dm.dmDisplayFrequency == 0 ||
      dm.dmDisplayFrequency >= MIN_FREQUENCY)) {
      ndmodes++;
    }
    mode++;
  }

  /* Allocate memory for a list of all the display modes. */
  dmodes = (DisplayMode*)
    malloc(ndmodes * sizeof(DisplayMode));

  /* Now that we know how many display modes to expect,
     enumerate them again and save the information in
     the list we allocated above. */
  i = 0;
  mode = 0;
  while (EnumDisplaySettings(NULL, mode, &dm)) {
    /* Try to reject any display settings that seem unplausible. */
    if (dm.dmPelsWidth >= MIN_WIDTH &&
      (dm.dmDisplayFrequency == 0 ||
      dm.dmDisplayFrequency >= MIN_FREQUENCY)) {
      dmodes[i].devmode = dm;
      dmodes[i].valid = 1;  /* XXX Not used for now. */
      dmodes[i].cap[DM_WIDTH] = dm.dmPelsWidth;
      dmodes[i].cap[DM_HEIGHT] = dm.dmPelsHeight;
      dmodes[i].cap[DM_PIXEL_DEPTH] = dm.dmBitsPerPel;
      if (dm.dmDisplayFrequency == 0) {
 	/* Guess a reasonable guess. */
	/* Lame Windows 95 version of EnumDisplaySettings. */
        dmodes[i].cap[DM_HERTZ] = 60;
      } else {
	dmodes[i].cap[DM_HERTZ] = dm.dmDisplayFrequency;
      }
      i++;
    }
    mode++;
  }

  assert(i == ndmodes);
}

#else

/* X Windows version of initGameModeSupport. */
static void
initGameModeSupport(void)
{
  if (ndmodes >= 0) {
    /* ndmodes is initially -1 to indicate no
       dmodes allocated yet. */
    return;
  }

  /* Determine how many display modes there are. */
  ndmodes = 0;
}

#endif

/* This routine is based on similiar code in glut_dstr.c */
static DisplayMode *
findMatch(DisplayMode * dmodes, int ndmodes,
  Criterion * criteria, int ncriteria)
{
  DisplayMode *found;
  int *bestScore, *thisScore;
  int i, j, numok, result = 0, worse, better;

  found = NULL;
  numok = 1;            /* "num" capability is indexed from 1,
                           not 0. */

  /* XXX alloca canidate. */
  bestScore = (int *) malloc(ncriteria * sizeof(int));
  if (!bestScore) {
    __glutFatalError("out of memory.");
  }
  for (j = 0; j < ncriteria; j++) {
    /* Very negative number. */
    bestScore[j] = -32768;
  }

  /* XXX alloca canidate. */
  thisScore = (int *) malloc(ncriteria * sizeof(int));
  if (!thisScore) {
    __glutFatalError("out of memory.");
  }

  for (i = 0; i < ndmodes; i++) {
    if (dmodes[i].valid) {
      worse = 0;
      better = 0;

      for (j = 0; j < ncriteria; j++) {
        int cap, cvalue, dvalue;

        cap = criteria[j].capability;
        cvalue = criteria[j].value;
        if (cap == NUM) {
          dvalue = numok;
        } else {
          dvalue = dmodes[i].cap[cap];
        }
#ifdef TEST
        if (verbose)
          printf("  %s %s %d to %d\n",
            capstr[cap], compstr[criteria[j].comparison], cvalue, dvalue);
#endif
        switch (criteria[j].comparison) {
        case EQ:
          result = cvalue == dvalue;
          thisScore[j] = 1;
          break;
        case NEQ:
          result = cvalue != dvalue;
          thisScore[j] = 1;
          break;
        case LT:
          result = dvalue < cvalue;
          thisScore[j] = dvalue - cvalue;
          break;
        case GT:
          result = dvalue > cvalue;
          thisScore[j] = dvalue - cvalue;
          break;
        case LTE:
          result = dvalue <= cvalue;
          thisScore[j] = dvalue - cvalue;
          break;
        case GTE:
          result = (dvalue >= cvalue);
          thisScore[j] = dvalue - cvalue;
          break;
        case MIN:
          result = dvalue >= cvalue;
          thisScore[j] = cvalue - dvalue;
          break;
        }

#ifdef TEST
        if (verbose)
          printf("                result=%d   score=%d   bestScore=%d\n", result, thisScore[j], bestScore[j]);
#endif

        if (result) {
          if (better || thisScore[j] > bestScore[j]) {
            better = 1;
          } else if (thisScore[j] == bestScore[j]) {
            /* Keep looking. */
          } else {
            goto nextDM;
          }
        } else {
          if (cap == NUM) {
            worse = 1;
          } else {
            goto nextDM;
          }
        }

      }

      if (better && !worse) {
        found = &dmodes[i];
        for (j = 0; j < ncriteria; j++) {
          bestScore[j] = thisScore[j];
        }
      }
      numok++;

    nextDM:;

    }
  }
  free(bestScore);
  free(thisScore);
  return found;
}

/**
 * Parses strings in the form of:
 *  800x600
 *  800x600:16
 *  800x600@60
 *  800x600:16@60
 *  @60
 *  :16
 *  :16@60
 * NOTE that @ before : is not parsed.
 */
static int
specialCaseParse(char *word, Criterion * criterion, int mask)
{
  char *xstr, *response;
  int got;
  int width, height, bpp, hertz;

  switch(word[0]) {
  case '0':
  case '1':
  case '2':
  case '3':
  case '4':
  case '5':
  case '6':
  case '7':
  case '8':
  case '9':
    /* The WWWxHHH case. */
    if (mask & (1 << DM_WIDTH)) {
      return -1;
    }
    xstr = strpbrk(&word[1], "x");
    if (xstr) {
      width = (int) strtol(word, &response, 0);
      if (response == word || response[0] != 'x') {
        /* Not a valid number OR needs to be followed by 'x'. */
	return -1;
      }
      height = (int) strtol(&xstr[1], &response, 0);
      if (response == &xstr[1]) {
        /* Not a valid number. */
	return -1;
      }
      criterion[0].capability = DM_WIDTH;
      criterion[0].comparison = EQ;
      criterion[0].value = width;
      criterion[1].capability = DM_HEIGHT;
      criterion[1].comparison = EQ;
      criterion[1].value = height;
      got = specialCaseParse(response,
        &criterion[2], 1 << DM_WIDTH);
      if (got >= 0) {
        return got + 2;
      } else {
        return -1;
      }
    }
    return -1;
  case ':':
    /* The :BPP case. */
    if (mask & (1 << DM_PIXEL_DEPTH)) {