int positional_source::calculate_volume(const map_location &loc, const display &disp)
{
assert(range_ > 0);
assert(faderange_ > 0);
if((check_shrouded_ && disp.shrouded(loc)) || (check_fogged_ && disp.fogged(loc)))
return DISTANCE_SILENT;
SDL_Rect area = disp.map_area();
map_location center = disp.hex_clicked_on(area.x + area.w / 2, area.y + area.h / 2);
int distance = distance_between(loc, center);
if(distance <= range_) {
return 0;
}
return static_cast<int>((((distance - range_)
/ static_cast<double>(faderange_)) * DISTANCE_SILENT));
}
void positional_source::update_positions(unsigned int time, const display &disp)
{
int distance_volume = DISTANCE_SILENT;
for(std::vector<map_location>::iterator i = locations_.begin(); i != locations_.end(); ++i) {
if(disp.shrouded(*i) || (check_fogged_ && disp.fogged(*i)))
continue;
int v = calculate_volume(*i, disp);
if(v < distance_volume) {
distance_volume = v;
}
}
if(sound::is_sound_playing(id_)) {
sound::reposition_sound(id_, distance_volume);
} else {
update(time, disp);
}
}
//our definition of map labels being obscured is if the tile is obscured,
//or the tile below is obscured. This is because in the case where the tile
//itself is visible, but the tile below is obscured, the bottom half of the
//tile will still be shrouded, and the label being drawn looks weird
static bool is_shrouded(const display& disp, const map_location& loc)
{
return disp.shrouded(loc) || disp.shrouded(map_location(loc.x,loc.y+1));
}