void draw_turtle(ModeInfo * mi) { turtlestruct *tp; if (turtles == NULL) return; tp = &turtles[MI_SCREEN(mi)]; if (++tp->time > MI_CYCLES(mi)) init_turtle(mi); MI_IS_DRAWN(mi) = True; if (MI_NPIXELS(mi) > 2) XSetForeground(MI_DISPLAY(mi), MI_GC(mi), MI_PIXEL(mi, NRAND(MI_NPIXELS(mi)))); tp->r = tp->r >> 1; tp->level++; if (tp->r > 1) switch (tp->curve) { case HILBERT: switch (tp->dir) { case 0: tp->pt1.x = tp->pt2.x = tp->start.x + tp->r / 2; tp->pt1.y = tp->pt2.y = tp->start.y + tp->r / 2; generate_hilbert(mi, 0, tp->r); break; case 1: tp->pt1.x = tp->pt2.x = tp->start.x + tp->min - tp->r / 2; tp->pt1.y = tp->pt2.y = tp->start.y + tp->min - tp->r / 2; generate_hilbert(mi, 0, -tp->r); break; case 2: tp->pt1.x = tp->pt2.x = tp->start.x + tp->min - tp->r / 2; tp->pt1.y = tp->pt2.y = tp->start.y + tp->min - tp->r / 2; generate_hilbert(mi, -tp->r, 0); break; case 3: tp->pt1.x = tp->pt2.x = tp->start.x + tp->r / 2; tp->pt1.y = tp->pt2.y = tp->start.y + tp->r / 2; generate_hilbert(mi, tp->r, 0); } break; case CESARO_VAR: generate_cesarovar(mi, (double) tp->pt1.x, (double) tp->pt1.y, (double) tp->pt2.x, (double) tp->pt2.y, tp->level, tp->sign); break; case HARTER_HEIGHTWAY: generate_harter_heightway(mi, (double) tp->pt1.x, (double) tp->pt1.y, (double) tp->pt2.x, (double) tp->pt2.y, tp->level, tp->sign); break; } }
void main() { /* initialize turtle graphics */ init_turtle(); /* draw 'V' */ vee(40, 10); right(180); vee(40, 10); /* wait for user to click right mouse button */ wait_button(); }