Map menu

The map menu allows you to choose the map you are going to play on. A map is defined by 3 things: 
* A frame. 
* A texture for walls. 
* A texture for the zone where fighters are allowed to move. 

In the middle of the screen, there is a preview of the level.
In this menu, the values of the parameters can be independently changed by: 
* Moving a slider. 
* Clicking on a + or a - button. 
* Typing a number. 

The frame can be chosen with the slider which is below the preview.
The frames are automatically re-ordered so that the fatest ones should be on the left, and the slowest ones, which are also the most complex ones, on the right. 

On each side of the preview, sliders allow you to choose the two textures.
There is also a preview of each texture.
Below this preview there are 128 little buttons which allow you to choose single colored textures. 