src/libs/glut/glutDstr.cpp

   1 /***********************************************************
   2  *      Copyright (C) 1997, Be Inc.  Copyright (C) 1999, Jake Hamby.
   3  *
   4  * This program is freely distributable without licensing fees
   5  * and is provided without guarantee or warrantee expressed or
   6  * implied. This program is -not- in the public domain.
   7  *
   8  *
   9  *  FILE:       glutDstr.cpp
  10  *
  11  *      DESCRIPTION:    convert display string into a Be options variable
  12  ***********************************************************/
  13
  14 /***********************************************************
  15  *      Headers
  16  ***********************************************************/
  17 #include <GL/glut.h>
  18 #include <string.h>
  19 #include <stdlib.h>
  20 #include "glutint.h"
  21 #include "glutState.h"
  22
  23 /***********************************************************
  24  *      FUNCTION:       glutInitDisplayString
  25  *
  26  *      DESCRIPTION:  sets the display string variable
  27  ***********************************************************/
  28 void APIENTRY
  29 glutInitDisplayString(const char *string)
  30 {
  31   if (gState.displayString) {
  32     free(gState.displayString);
  33   }
  34   if (string) {
  35     gState.displayString = strdup(string);
  36     if (!gState.displayString)
  37       __glutFatalError("out of memory.");
  38   } else
  39     gState.displayString = NULL;
  40 }
  41
  42 /***********************************************************
  43  *      FUNCTION:       __glutConvertDisplayModeFromString
  44  *
  45  *      DESCRIPTION:  converts the current display mode into a BGLView
  46  *              display mode, printing warnings as appropriate.
  47  *
  48  *      PARAMETERS:      if options is non-NULL, the current display mode is
  49  *              returned in it.
  50  *
  51  *      RETURNS:        1 if the current display mode is possible, else 0
  52  ***********************************************************/
  53 int __glutConvertDisplayModeFromString(unsigned long *options) {
  54         ulong newoptions = 0;
  55
  56         char *word = strtok(gState.displayString, " \t");
  57         do {
  58                 char *cstr = strpbrk(word, "=><!~");
  59                 if(cstr)
  60                         *cstr = '\0';
  61                 // this is the most minimal possible parser.  scan for
  62                 // options that we support, and add them to newoptions
  63                 // this will certainly cause it to accept things that we
  64                 // don't actually support, but if we don't support it, the
  65                 // program's probably not going to work anyway.
  66                 if(!strcmp(word, "alpha")) {
  67                         newoptions |= BGL_ALPHA;
  68                 } else if((!strcmp(word, "acc")) || (!strcmp(word, "acca"))) {
  69                         newoptions |= BGL_ACCUM;
  70                 } else if(!strcmp(word, "depth")) {
  71                         newoptions |= BGL_DEPTH;
  72                 } else if(!strcmp(word, "double")) {
  73                         newoptions |= BGL_DOUBLE;
  74                 } else if(!strcmp(word, "stencil")) {
  75                         newoptions |= BGL_STENCIL;
  76                 }
  77         } while((word = strtok(0, " \t")) != 0);
  78
  79         if (options)
  80                 *options = newoptions;
  81
  82         return 1;       // assume we support it
  83 }