void zeichne(cairo_t *cr, const double x1, const double y1, const double x2, const double y2,
const double x3, const double y3, const unsigned tiefe) {
if (tiefe <= 0) {
triangle(cr, x1, y1, x2, y2, x3, y3);
return;
}
zeichne(cr, x1, y1, (x1 + x2) / 2, (y1 + y2) / 2,
(x1 + x3) / 2, (y1 + y3) / 2, tiefe - 1);
zeichne(cr, (x1 + x2) / 2, (y1 + y2) / 2, x2, y2,
(x2 + x3) / 2, (y2 + y3) / 2, tiefe - 1);
zeichne(cr, (x1 + x3) / 2, (y1 + y3) / 2,
(x2 + x3) / 2, (y2 + y3) / 2, x3, y3, tiefe - 1);
}
int main() {
// Auflösung in Pixeln
const double res = 1000;
const double xsize = res;
const double ysize = sin(M_PI / 3) * res;
// Breite einer Linie in Pixeln
const double line_width = 3;
// maximale Anzahl Iterationen
const unsigned int iterations = 7;
cairo_surface_t *surface = cairo_image_surface_create (
CAIRO_FORMAT_ARGB32, xsize, ysize);
cairo_t *cr = cairo_create (surface);
cairo_scale(cr, res, res);
cairo_set_line_width (cr, line_width / res);
cairo_set_source_rgb (cr, 0, 0, 0);
const double space = 0.05;
zeichne(cr, space, sin(M_PI / 3) - space, 1 - space,
sin(M_PI / 3) - space, 0.5, space, iterations);
cairo_destroy (cr);
cairo_surface_write_to_png (surface, "sierpinski.png");
cairo_surface_destroy (surface);
return 0;
}
int main()
{
Linie l;
Kreis k, k1, k2;
zeichne(l); // zeichne(GeoObj&) => Linie::draw()
zeichne(k); // zeichne(GeoObj&) => Kreis::draw()
abstand(k1,k2); // abstand(GeoObj&,GeoObj&)
abstand(l,k); // abstand(GeoObj&,GeoObj&)
std::vector<GeoObj*> menge; // inhomogene Menge
menge.push_back(&l); // Linie einfügen
menge.push_back(&k); // Kreis einfügen
ausgeben(menge); // Menge ausgeben
}
/* ************************************************************* */
int next_zeit_cb()
/* ************************************************************* */
{
char c_zeit[10];
int eq = 0;
g_animation.anim_frame = (g_animation.anim_frame) ? g_animation.anim_frame : 1;
if (( eq = g_animation.akt_index % g_animation.anim_frame ) == 0)
{
lese_next_zeit();
glMatrixMode (GL_PROJECTION);
glLoadIdentity ();
C3D_updateref();
zeichne();
sprintf(c_zeit, "%8.3f", g_animation.zeiten[g_animation.akt_index]);
XmTextFieldSetString(widgetMain.T_zeitschritt, c_zeit);
return 1;
}
else
{
/* increase actual index frame */
if(g_animation.akt_index >= g_animation.anim_ende)
g_animation.akt_index = g_animation.anim_anfang;
else
g_animation.akt_index++;
return 0;
}
/* ************************************************************* */
}
