X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=progs%2Fdemos%2FFractals%2Ffractals.c;h=9bb3bfe2cc86d4eefa72d0b741f7906f496522a1;hb=d1d57758967d67f5588cd5d3ce49cb3073eae527;hp=644b33724a63690d332d09458944e89489e00d62;hpb=1fdf3d47e17bb436f139c8a69ee28d36a881820d;p=freeglut

diff --git a/progs/demos/Fractals/fractals.c b/progs/demos/Fractals/fractals.c
index 644b337..9bb3bfe 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
@@ -83,7 +84,7 @@ static void draw_level ( int num, double m00, double m01, double m10, double m11
 static void 
 Display(void)
 {
-  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+  glClear( GL_COLOR_BUFFER_BIT );
 
   /* the curve */
   glPushMatrix();
@@ -106,7 +107,10 @@ Reshape(int width, int height)
   glMatrixMode ( GL_PROJECTION ) ;
   glLoadIdentity();
   ar = (float) width / (float) height ;
-  glFrustum ( -ar, ar, -1.0, 1.0, 2.0, 100.0 ) ;
+  if( ar > 1 )
+      glFrustum ( -ar, ar, -1.0, 1.0, 2.0, 100.0 ) ;
+  else
+      glFrustum ( -1.0, 1.0, -1/ar, 1/ar, 2.0, 100.0 );
   glMatrixMode ( GL_MODELVIEW ) ;
   glLoadIdentity () ;
   xwin = -1.0 ;
@@ -117,6 +121,8 @@ 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 () ;
@@ -137,16 +143,21 @@ 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 ) ;
@@ -187,49 +198,76 @@ Special(int key, int x, int y)
     glTranslated ( xwin, ywin, 0.0 ) ;
     scale_factor *= 1.25 ;
     break ;
-  }
 
-  glutPostRedisplay();
+  default:
+    need_redisplay = 0;
+    break;
+  }
+  if (need_redisplay)
+    glutPostRedisplay();
 }
 
+
 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 */
+    fgets ( inputline, 256, fptr ) ;
 
-  /* Read a comment line */
-  fgets ( inputline, 256, fptr ) ;
+    /* Read a comment line */
+    fgets ( inputline, 256, fptr ) ;
 
-  /* Read the window title */
-  fgets ( inputline, 256, fptr ) ;
-  sscanf ( inputline, "%[a-zA-Z0-9!@#$%^&*()+=/\\_-\" ]", window_title ) ;
+    /* Read the window title */
+    fgets ( inputline, 256, fptr ) ;
+    /* We assume here that this line will not exceed 79 characters plus a 
+       newline (window_title is 80 characters long). That'll cause a buffer 
+       overflow. For a simple program like  this, though, we're letting it 
+       slide! 
+    */
+    sscanf ( inputline, "%[a-zA-Z0-9!@#$%^&*()+=/\\_-\" ]", window_title ) ; 
+
+    /* Read a comment line */
+    fgets ( inputline, 256, fptr ) ;
 
-  /* Read a comment line */
-  fgets ( inputline, 256, fptr ) ;
+    /* Read the number of affine transformations */
+    fgets ( inputline, 256, fptr ) ;
+    sscanf ( inputline, "%d", &num_trans ) ;
 
-  /* Read the number of affine transformations */
-  fgets ( inputline, 256, 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 */
-  fgets ( inputline, 256, fptr ) ;
+    for ( i = 0; i < num_trans; i++ )
+    {
+      /* 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 ) ;
+    }
+  }
+  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 ;
@@ -254,17 +292,16 @@ main(int argc, char *argv[])
 {
   int fractal_window ;
 
+  glutInitWindowSize(500, 250);
+  glutInitWindowPosition ( 140, 140 );
+  glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE );
+  glutInit(&argc, argv);
+
   if ( argc > 1 )
     readConfigFile ( argv[1] ) ;
   else
     readConfigFile ( "fractals.dat" ) ;
 
-  glutInit(&argc, argv);
-  glutInitWindowSize(500, 250);
-  glutInitWindowPosition ( 140, 140 ) ;
-
-  glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
-
   fractal_window = glutCreateWindow( window_title );
 
   glClearColor(1.0, 1.0, 1.0, 1.0);