Yet this can also used to put hidden features and secret passages too.
==Control and Gameplay==
A porjection environment can be used as 2D or 3D environment/engine.
*'''Horizontal Oblique :'''
Because it still have some traditional Horizontal and vertical axis, this projection often stick to the up/down and left/right way to move the Player's sprite. as a result, this projection if more than often only cosmetic : the background looks like 3D but the game and the sprites are clearly 2D.
**'''2D :''' As in most beat'hem all like Renegade. Or even some shooters like MagMax. They are indeed 2D games. The vertical axis being only limited to jumps on the X axis (left/right) if available.
**'''3D :''' Pacmania is a complete example of a real '''oblique 3D'''.
To move vertically, you need to jump, otherwise the basic 4 directions really stick to the 2 horizontal plane axis', one of them being "diagonal". This is helped by the rail-roaded aspect of the labyrinth which prevent any Diagonal to be exploited. As a result, you can jump in X and Z axis.
*'''Isometric :'''
Isometric environment has some issues concerning distances.
a Square's diagonals are longer the its sides.
To get a realistic distance/time ratio, you may need to compensate or else the diagonal moves can be exploited.
The same problem happens in 2D games anyway and in all 8 direction planes (square grid).
Real Isometric 3D environment lead to some diagonal horizontal (X and Z axis) movement problems : the 2 horizontal plane axis (X and Z) are (visually) diagonals... but the joystick does not use its diagonal to move in X/Z axis. So you have to choose whether you use X=left/Right and Z=up/down or X=up/down and Z= left/Right... (orientation of the joystick to the right or left...)
Some isometric games enable you to move horizontally in 8 direction... such engine often don't manage the vertical axis (jump) and are therefore often 2D.
*'''3D :''' Head over heels example.
You move on the horizontal plan with only 4 directions (X and Z axis), and you can jump (Y axis) to get some platformer gameplay.
**'''2D :'''Gauntlet 3 is some precursor of Diablo-like games.
The backgrounds elements are in 3D but you can't use the Y vertical axis, therefore you can move on the horizontal plane in 8 direction.
But this leads to a strange and odd impression as the levels are designed in diagonals but the player would instinctively move mostly in up/down/left/right 2D fashion.
*'''Isometric :'''
==Modern day isometric==
==Links==
Wikipedias '''Wikipedia's''' articles :
[http://en.wikipedia.org/wiki/Graphical_projection| Graphical projection]