ef_smoke;
返回： N/A
This constant is for use in the functions effect_create_above and
effect_create_below, and
will create a smoke effect as illustrated in the image below:
if speed > 0
{
effect_create_below(ef_smoke, x, y, choose(0, 1, 2), c_gray);
}
The above code will create a smoke trail from the instance when the speed is greater than 0.