This bug/feature has been plaguing me for a while and i want to know the best way to fix it. I'm testing simple hit detection with a wall, like:

 if (Forward button)
        if(Inv.w.z < -49 || Inv.w.z > 49)
            pos.z = 0.0f;
        else if(Inv.w.x < -49 || Inv.w.x > 49)
            pos.z = 0.0f;
        else
            pos.z = +1.0f;

where Inv.w. is the camera positions. Now obviously when i now hit that certain point i can no longer move away from the wall or anywhere in fact. How can i change this code to allow for the camera to be turned away from the wall so therefore i should be allowed to move?

for example, the player hits the wall and i cant move until i turn around or to the side?

I know its something to do with velocity but im pretty new to this so please bare with me if this is easy.