[mansonh]

as for detecting walls etc
There is a mysql database plugin which has map heights, so you can find the z coordinate which includes building tops etc.
[REL,beta] MapAndreas plugin v1.0

So to detect a wall use this function with distance to detect a wall(think its ******'s code):

Code:

stock GetXYInFrontOfPlayer(playerid, &Float:x, &Float:y, Float:distance)
{
	new Float:a;
	GetPlayerPos(playerid, x, y, a);
	GetPlayerFacingAngle(playerid, a);
	x += (distance * floatsin(-a, degrees));
	y += (distance * floatcos(-a, degrees));
}

Then use the mysql to determine the z coordinate, if its higher than you are, you have a wall.