//note I use project and unproject here as an example of how to use each and what you can do with them there are other alternative ways to do this.
//X and Y are normalized screen cords of the mouse we bring them back in to screen cords to 
WindowRectangle rec = ()->GetWindowRect();
	x *= rec.width;
	y *= rec.height;
 
	D3DXMATRIX ident;
	D3DXMATRIXIdentity(&ident);
 
	D3DXVECTOR3 out;
	D3DXVec3Project(&out, tankPosition,gameViewPort,projectionMatrix,viewMatrix,&ident);
 
//screen x and y
//z is the depth between the near clip plane and far clip plane
	D3DXVECTOR3 mouseVecTank = D3DXVECTOR3(x, y, out.z);
	D3DXVECTOR3 mouseVecTankOut;
 
 
	D3DXVec3Unproject(&mouseVecTankOut, &mouseVecTank, gameViewPort, projectionMatrix, viewMatrix, &ident);
 
 
	//if im not mistaken this can be replaced by taking the dot product of the tank forward vector and the direction to the mouse and using the angle returned from that. That may be faster than doing atan2f
 
	D3DXVECTOR3 dir = mouseVecTankOut – tankWorldTranslation
	D3DXVec3Normalize(&dir,&dir);
	Float angleFromUnitToMouse = atan2f(dir.x,dir.z);

--Example
Window = {
	X = 0,
	Y = 0,
	Width = 640,
	Height = 480,
	Name =  "My game",
	FullScreen = false
}

tableValues = {
	"window.x",
	"window.y",
	"window.width",
	"window.height",
	"window.name",
	"window.FullScreen"
}
--To get this format is simple, just pass the table name and table to this function
tempValues = {}
tempTableNames = {strTableName}
tempTables = {tblTable}
for i,n in pairs(tempTables) do
	for j,m in pairs(n) do
		if(type(m) == "table") then
			table.insert(tempTableNames,string.format("%s.%s",tempTableNames[i],j))
			table.insert(tempTables,m)
		else
			table.insert(tempValues,string.format("%s.%s",tempTableNames[i],j))
		end
	end
end