X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=progs%2Fdemos%2FFractals%2Ffractals.c;h=1aef1c4107e9c86307ac06b50c81e12255782dff;hb=3a62f01ded704b52999ca8b22f9cd7b6abb251f5;hp=ee002452aa95dbaadc8f615379036ae317eea282;hpb=017c50018bb3c3f36179d7b97ab0e6f7545fc78e;p=freeglut

diff --git a/progs/demos/Fractals/fractals.c b/progs/demos/Fractals/fractals.c
index ee00245..1aef1c4 100644
--- a/progs/demos/Fractals/fractals.c
+++ b/progs/demos/Fractals/fractals.c
@@ -21,6 +21,7 @@
 #include <GL/freeglut.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <math.h>
 
 typedef struct
@@ -38,6 +39,9 @@ static int num_levels = 0 ;
 static int num_trans ;
 static AffineTrans *affine ;
 
+/* Flag telling us to keep executing the main loop */
+static int continue_in_main_loop = 1;
+
 /* the window title */
 char window_title [ 80 ] ;
 
@@ -120,9 +124,11 @@ Reshape(int width, int height)
 static void 
 Key(unsigned char key, int x, int y)
 {
+  int need_redisplay = 1;
+  
   switch (key) {
   case 27:  /* Escape key */
-    glutLeaveMainLoop () ;
+    continue_in_main_loop = 0 ;
     break;
 
   case '+' :
@@ -140,16 +146,21 @@ Key(unsigned char key, int x, int y)
     xwin = -1.0 ;
     ywin = 0.0 ;
     glTranslated ( xwin, ywin, -5.0 ) ;
-
     break ;
-  }
 
-  glutPostRedisplay();
+  default:
+    need_redisplay = 0;
+    break;
+  }
+  if (need_redisplay)
+    glutPostRedisplay();
 }
 
 static void 
 Special(int key, int x, int y)
 {
+  int need_redisplay = 1;
+
   switch (key) {
   case GLUT_KEY_UP :
     glMatrixMode ( GL_MODELVIEW ) ;
@@ -190,54 +201,86 @@ Special(int key, int x, int y)
     glTranslated ( xwin, ywin, 0.0 ) ;
     scale_factor *= 1.25 ;
     break ;
+
+  default:
+    need_redisplay = 0;
+    break;
   }
+  if (need_redisplay)
+    glutPostRedisplay();
+}
 
-  glutPostRedisplay();
+
+static void
+checkedFGets ( char *s, int size, FILE *stream )
+{
+  if ( fgets ( s, size, stream ) == NULL ) {
+    fprintf ( stderr, "fgets failed\n");
+    exit ( EXIT_FAILURE );
+  }
 }
 
+
 void readConfigFile ( char *fnme )
 {
   FILE *fptr = fopen ( fnme, "rt" ) ;
   int i ;
   char inputline [ 256 ] ;
 
-  /* Read a header line */
-  fgets ( inputline, 256, fptr ) ;
+  if ( fptr )
+  {
+    /* Read a header line */
+    checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
 
-  /* Read a comment line */
-  fgets ( inputline, 256, fptr ) ;
+    /* Read a comment line */
+    checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
 
-  /* Read the window title */
-  fgets ( inputline, 256, fptr ) ;
-  /* We assume here that this line will not exceed 79 characters plus a 
-     newline (window_title is 80 characters long). That'll cause a buffer 
-     overflow. For a simple program like  this, though, we're letting it 
-     slide! 
-  */
-  sscanf ( inputline, "%[a-zA-Z0-9!@#$%^&*()+=/\\_-\" ]", window_title ) ; 
+    /* Read the window title */
+    checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
+    /* We assume here that this line will not exceed 79 characters plus a 
+       newline (window_title is 80 characters long). That'll cause a buffer 
+       overflow. For a simple program like  this, though, we're letting it 
+       slide! 
+    */
+    sscanf ( inputline, "%[a-zA-Z0-9!@#$%^&*()+=/\\_-\" ]", window_title ) ; 
 
-  /* Read a comment line */
-  fgets ( inputline, 256, fptr ) ;
+    /* Read a comment line */
+    checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
 
-  /* Read the number of affine transformations */
-  fgets ( inputline, 256, fptr ) ;
-  sscanf ( inputline, "%d", &num_trans ) ;
+    /* Read the number of affine transformations */
+    checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
+    sscanf ( inputline, "%d", &num_trans ) ;
 
-  affine = (AffineTrans *)malloc ( num_trans * sizeof(AffineTrans) ) ;
+    affine = (AffineTrans *)malloc ( num_trans * sizeof(AffineTrans) ) ;
 
-  /* Read a comment line */
-  fgets ( inputline, 256, fptr ) ;
+    /* Read a comment line */
+    checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
+
+    for ( i = 0; i < num_trans; i++ )
+    {
+      /* Read an affine transformation definition */
+      checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
+      sscanf ( inputline, "%lf %lf %lf %lf %lf %lf", &affine[i].a00, &affine[i].a01,
+                       &affine[i].a10, &affine[i].a11, &affine[i].b0, &affine[i].b1 ) ;
+    }
+  }
+  else  /* No data file, set a default */
+  {
+    printf ( "ERROR opening file <%s>\n", fnme ) ;
+    strcpy ( window_title, "Cantor Dust" ) ;
+    num_trans = 2 ;
+    affine = (AffineTrans *)malloc ( num_trans * sizeof(AffineTrans) ) ;
+    affine[0].a00 = 0.25 ;  affine[0].a01 = 0.00 ;  affine[0].a10 = 0.00 ;  affine[0].a11 = 0.25 ;
+    affine[0].b0 = 0.0 ;    affine[0].b1 = 0.0 ;
+    affine[1].a00 = 0.25 ;  affine[1].a01 = 0.00 ;  affine[1].a10 = 0.00 ;  affine[1].a11 = 0.25 ;
+    affine[1].b0 = 0.5 ;    affine[1].b1 = 0.0 ;
+  }
 
   for ( i = 0; i < num_trans; i++ )
   {
     double m00, m01, m10, m11 ;  /* Matrix "I" minus "A" */
     double determ ;              /* Determinant of this matrix */
 
-    /* Read an affine transformation definition */
-    fgets ( inputline, 256, fptr ) ;
-    sscanf ( inputline, "%lf %lf %lf %lf %lf %lf", &affine[i].a00, &affine[i].a01,
-                     &affine[i].a10, &affine[i].a11, &affine[i].b0, &affine[i].b1 ) ;
-
     /* Calculate the stationary point */
 
     m00 = 1.0 - affine[i].a00 ;
@@ -281,7 +324,11 @@ main(int argc, char *argv[])
   glutSpecialFunc(Special);
   glutDisplayFunc(Display);
 
-  glutMainLoop();
+#ifdef WIN32
+#endif
+
+  while ( continue_in_main_loop )
+    glutMainLoopEvent();
 
   printf ( "Back from the 'freeglut' main loop\n" ) ;