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-rwxr-xr-xSixenseSDK/src/sixense_simple3d/progs/demos/Fractals/fractals.c336
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diff --git a/SixenseSDK/src/sixense_simple3d/progs/demos/Fractals/fractals.c b/SixenseSDK/src/sixense_simple3d/progs/demos/Fractals/fractals.c
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+++ b/SixenseSDK/src/sixense_simple3d/progs/demos/Fractals/fractals.c
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+/* fractals.c */
+/*
+ * Program to draw a fractal by Michael Barnsley's deterministic algorithm.
+ * Algorithm:
+ * (1) Define the affine transformations (of the form r(i+1) = A r(i) + b )
+ * (2) Find the stationary point for each transformation
+ * (3) To draw:
+ * - If you are at the lowest level, draw lines connecting all the stationary points
+ * - If not, call the draw function recursively with each affine transformation applied
+ */
+
+/*
+ * User Commands:
+ * +,- - increment/decrement number of levels
+ * PgUp, PgDn - increase/decrease scaling
+ * Arrow keys - translate viewing section
+ * r - reset view
+ * Escape - quit
+ */
+
+#include <GL/freeglut.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+typedef struct
+{
+ double a00, a01, a10, a11 ; /* Transformation matrix */
+ double b0, b1 ; /* Constant vector added on */
+ double statx, staty ; /* Coordinates of the stationary point */
+}
+AffineTrans ;
+
+/* Number of levels to draw the fractal */
+static int num_levels = 4 ;
+
+/* The definition of the fractal */
+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 ] ;
+
+/* The amount the view is translated and scaled */
+double xwin = 0.0, ywin = 0.0 ;
+double scale_factor = 1.0 ;
+
+static void draw_level ( int num, double m00, double m01, double m10, double m11, double n0, double n1 )
+{
+ /* Draw a fractal transformed by "M", "N" as passed in */
+ int i ;
+
+ if ( num == 0 )
+ {
+ double x0 = m00 * affine[0].statx + m01 * affine[0].staty + n0 ;
+ double y0 = m10 * affine[0].statx + m11 * affine[0].staty + n1 ;
+
+ for ( i = 1; i < num_trans; i++ )
+ {
+ double x1 = m00 * affine[i].statx + m01 * affine[i].staty + n0 ;
+ double y1 = m10 * affine[i].statx + m11 * affine[i].staty + n1 ;
+
+ glVertex2d ( x0, y0 ) ;
+ glVertex2d ( x1, y1 ) ;
+
+ x0 = x1 ;
+ y0 = y1 ;
+ }
+ }
+ else
+ {
+ /* Map each affine transformation in the fractal through the one passed in and call "draw_level" */
+
+ for ( i = 0; i < num_trans; i++ )
+ {
+ draw_level ( num-1, m00*affine[i].a00+m01*affine[i].a10, m00*affine[i].a01+m01*affine[i].a11,
+ m10*affine[i].a00+m11*affine[i].a10, m10*affine[i].a01+m11*affine[i].a11,
+ m00*affine[i].b0 +m01*affine[i].b1 + n0, m10*affine[i].b0 +m11*affine[i].b1 + n1 ) ;
+ }
+ }
+}
+
+static void
+Display(void)
+{
+ glClear( GL_COLOR_BUFFER_BIT );
+
+ /* the curve */
+ glPushMatrix();
+ glScalef(2.5, 2.5, 2.5);
+
+ glColor4f(0.0, 0.0, 0.0, 1.0);
+ glBegin ( GL_LINES ) ;
+ draw_level ( num_levels, 1.0, 0.0, 0.0, 1.0, 0.0, 0.0 );
+ glEnd () ;
+
+ glPopMatrix();
+ glutSwapBuffers();
+}
+
+static void
+Reshape(int width, int height)
+{
+ float ar;
+ glViewport ( 0, 0, width, height ) ;
+ glMatrixMode ( GL_PROJECTION ) ;
+ glLoadIdentity();
+ ar = (float) width / (float) height ;
+ 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 ;
+ ywin = 0.0 ;
+ glTranslated ( xwin, ywin, -5.0 ) ;
+}
+
+static void
+Key(unsigned char key, int x, int y)
+{
+ int need_redisplay = 1;
+
+ switch (key) {
+ case 27: /* Escape key */
+ continue_in_main_loop = 0 ;
+ break;
+
+ case '+' :
+ ++num_levels ;
+ break ;
+
+ case '-' :
+ if ( num_levels > 0 )
+ --num_levels ;
+ break ;
+
+ case 'r' : case 'R' :
+ glMatrixMode ( GL_MODELVIEW ) ;
+ glLoadIdentity();
+ xwin = -1.0 ;
+ ywin = 0.0 ;
+ glTranslated ( xwin, ywin, -5.0 ) ;
+ break ;
+
+ 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 ) ;
+ ywin += 0.1 * scale_factor ;
+ glTranslated ( 0.0, 0.1 * scale_factor, 0.0 ) ;
+ break ;
+
+ case GLUT_KEY_DOWN :
+ glMatrixMode ( GL_MODELVIEW ) ;
+ ywin -= 0.1 * scale_factor ;
+ glTranslated ( 0.0, -0.1 * scale_factor, 0.0 ) ;
+ break ;
+
+ case GLUT_KEY_LEFT :
+ glMatrixMode ( GL_MODELVIEW ) ;
+ xwin -= 0.1 * scale_factor ;
+ glTranslated ( -0.1 * scale_factor, 0.0, 0.0 ) ;
+ break ;
+
+ case GLUT_KEY_RIGHT :
+ glMatrixMode ( GL_MODELVIEW ) ;
+ xwin += 0.1 * scale_factor ;
+ glTranslated ( 0.1 * scale_factor, 0.0, 0.0 ) ;
+ break ;
+
+ case GLUT_KEY_PAGE_UP :
+ glMatrixMode ( GL_MODELVIEW ) ;
+ glTranslated ( -xwin, -ywin, 0.0 ) ;
+ glScaled ( 1.25, 1.25, 1.25 ) ;
+ glTranslated ( xwin, ywin, 0.0 ) ;
+ scale_factor *= 0.8 ;
+ break ;
+
+ case GLUT_KEY_PAGE_DOWN :
+ glMatrixMode ( GL_MODELVIEW ) ;
+ glTranslated ( -xwin, -ywin, 0.0 ) ;
+ glScaled ( 0.8, 0.8, 0.8 ) ;
+ glTranslated ( xwin, ywin, 0.0 ) ;
+ scale_factor *= 1.25 ;
+ break ;
+
+ default:
+ need_redisplay = 0;
+ break;
+ }
+ if (need_redisplay)
+ 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 ] ;
+
+ if ( fptr )
+ {
+ /* Read a header line */
+ checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
+
+ /* Read a comment line */
+ checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
+
+ /* 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 */
+ checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
+
+ /* Read the number of affine transformations */
+ checkedFGets ( inputline, sizeof ( inputline ), fptr ) ;
+ sscanf ( inputline, "%d", &num_trans ) ;
+
+ affine = (AffineTrans *)malloc ( num_trans * sizeof(AffineTrans) ) ;
+
+ /* 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 */
+
+ /* Calculate the stationary point */
+
+ m00 = 1.0 - affine[i].a00 ;
+ m01 = - affine[i].a01 ;
+ m10 = - affine[i].a10 ;
+ m11 = 1.0 - affine[i].a11 ;
+
+ determ = m00 * m11 - m01 * m10 ;
+
+ if ( fabs ( determ ) > 1.e-6 )
+ {
+ affine[i].statx = ( m11 * affine[i].b0 - m01 * affine[i].b1 ) / determ ;
+ affine[i].staty = ( -m10 * affine[i].b0 + m00 * affine[i].b1 ) / determ ;
+ }
+ else
+ affine[i].statx = affine[i].staty = 0.0 ;
+ }
+}
+
+int
+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" ) ;
+
+ fractal_window = glutCreateWindow( window_title );
+
+ glClearColor(1.0, 1.0, 1.0, 1.0);
+
+ glutReshapeFunc(Reshape);
+ glutKeyboardFunc(Key);
+ glutSpecialFunc(Special);
+ glutDisplayFunc(Display);
+
+#ifdef WIN32
+#endif
+
+ while ( continue_in_main_loop )
+ glutMainLoopEvent();
+
+ printf ( "Back from the 'freeglut' main loop\n" ) ;
+
+ return 0; /* ANSI C requires main to return int. */
+}
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