X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=progs%2Fdemos%2FFractals_random%2Ffractals_random.c;h=46a64e5e09c130f233010ea286bb41793371b2b4;hb=c1455b957d344441cb972fd6ad8880e37a6fdc01;hp=e401c706a067b7e8f39a6d1d6aeefa7973ca4fc7;hpb=0fc97b9a2b832dfea1beadb3bb3539b2fa72c637;p=freeglut diff --git a/progs/demos/Fractals_random/fractals_random.c b/progs/demos/Fractals_random/fractals_random.c index e401c70..46a64e5 100644 --- a/progs/demos/Fractals_random/fractals_random.c +++ b/progs/demos/Fractals_random/fractals_random.c @@ -50,6 +50,9 @@ float scale_factor = 1.0 ; /* The current point */ float current_x = 0.0, current_y = 0.0 ; +/* Signals when a glClear is needed */ +static GLboolean needClear = GL_TRUE; + 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 */ @@ -70,6 +73,11 @@ static void draw_level ( int num, double m00, double m01, double m10, double m11 static void Display(void) { + if (needClear) { + glClear(GL_COLOR_BUFFER_BIT); + needClear = GL_FALSE; + } + /* the curve */ glPushMatrix(); glScalef(2.5, 2.5, 2.5); @@ -81,7 +89,7 @@ Display(void) glPopMatrix(); - // glutSwapBuffers(); /* Should NOT be here... This is a Single-Buffered Program! */ + glFlush(); glutPostRedisplay(); /* Needed so that this function will be called again */ } @@ -93,17 +101,23 @@ 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 ; ywin = 0.0 ; glTranslatef(xwin, ywin, -5.0); + needClear = GL_TRUE; } static void Key(unsigned char key, int x, int y) { + int changed_settings = 1; + switch (key) { case 27: /* Escape key */ glutLeaveMainLoop (); @@ -115,18 +129,22 @@ Key(unsigned char key, int x, int y) xwin = -1.0 ; ywin = 0.0 ; glTranslatef(xwin, ywin, -5.0); - break ; - } - - glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + default: + changed_settings = 0; + break; + } + if (changed_settings) + needClear = GL_TRUE; glutPostRedisplay(); } static void Special(int key, int x, int y) { + int changed_settings = 1; + switch (key) { case GLUT_KEY_UP : glMatrixMode(GL_MODELVIEW); @@ -167,51 +185,78 @@ Special(int key, int x, int y) glTranslatef ( xwin, ywin, 0.0 ) ; scale_factor *= 1.25 ; break ; - } - glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + default: + changed_settings = 0; + break; + } + if (changed_settings) + needClear = GL_TRUE; 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 ; @@ -236,23 +281,21 @@ main(int argc, char *argv[]) { int fractal_window ; - if ( argc > 1 ) - readConfigFile ( argv[1] ) ; - else - readConfigFile ( "fractals.dat" ) ; + glutInitDisplayMode( GLUT_RGB | GLUT_SINGLE ); - glutInit(&argc, argv); glutInitWindowSize(500, 250); glutInitWindowPosition ( 140, 140 ) ; + glutInit(&argc, argv); - glutInitDisplayMode(GLUT_RGB | GLUT_SINGLE | GLUT_DEPTH); + if ( argc > 1 ) + readConfigFile ( argv[1] ) ; + else + readConfigFile ( "fractals.dat" ) ; fractal_window = glutCreateWindow( window_title ); glClearColor(1.0, 1.0, 1.0, 1.0); - glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); - glutReshapeFunc(Reshape); glutKeyboardFunc(Key); glutSpecialFunc(Special);