Ok there's a exemple :
----------------------------------------------------
my.pan += 3* (key_a - key_d) * time_step;
my.roll += 3* (key_d - key_a) * time_step;
speed.x += 3 * (key_w - key_s) * time_step;
speed.y += 3 * (key_z - key_c) * time_step;

c_move(my,speed,nullvector,IGNORE_PASSABLE|GLIDE)
----------------------------------------------------

When im moving on the X axis, if i change the .pan the entity now move following the pan angle... like a car...

Now there's my problem :
When im moving on the Y axis, if i change the .roll the entity now move up or down following the roll angle...

I dont want my entity to change his movement direction if i change roll angle when i move on the Y axis...I just want it to continue to move regardless the .roll angle.