/*
* Update the given polygon's position according to the given informations in
* polygon_move (polygon_move may be updated)
*/
static void polygon_update(struct polygon *polygon, struct polygon_move *polygon_move)
{
int i, x, y, step;
for(i = 0; i < NB_POINTS; ++i){
x = polygon->vx[i];
step = polygon_move->movex[i];
x += step;
if(x <= 0){
x = 1;
polygon_move->movex[i] = get_new_step(step);
}
else if(x >= ttk_screen->w){
x = ttk_screen->w - 1;
polygon_move->movex[i] = get_new_step(step);
}
polygon->vx[i] = x;
y = polygon->vy[i];
step = polygon_move->movey[i];
y += step;
if(y <= 0){
y = 1;
polygon_move->movey[i] = get_new_step(step);
}
else if(y >= ttk_screen->h){
y = ttk_screen->h - 1;
polygon_move->movey[i] = get_new_step(step);
}
polygon->vy[i] = y;
}
}
void polygon_move_init(struct polygon_move * polygon_move)
{
int i;
for(i=0; i<NB_POINTS; ++i)
{
polygon_move->move_steps[i].x=get_new_step(-1);
/* -1 because we want a positive random step */
polygon_move->move_steps[i].y=get_new_step(-1);
}
}
/*
* Update the given polygon's position according to the given informations in
* polygon_move (polygon_move may be updated)
*/
void polygon_update(struct polygon *polygon, struct screen * display, struct polygon_move *polygon_move)
{
int i, x, y, step;
for(i=0; i<NB_POINTS; ++i)
{
x=polygon->points[i].x;
step=polygon_move->move_steps[i].x;
x+=step;
if(x<=0)
{
x=1;
polygon_move->move_steps[i].x=get_new_step(step);
}
else if(x>=display->getwidth())
{
x=display->getwidth()-1;
polygon_move->move_steps[i].x=get_new_step(step);
}
polygon->points[i].x=x;
y=polygon->points[i].y;
step=polygon_move->move_steps[i].y;
y+=step;
if(y<=0)
{
y=1;
polygon_move->move_steps[i].y=get_new_step(step);
}
else if(y>=display->getheight())
{
y=display->getheight()-1;
polygon_move->move_steps[i].y=get_new_step(step);
}
polygon->points[i].y=y;
}
}
