SOLVED, see below.
The walls named by 1;2;3 and 4 are different just to better viewing.
My problem is that I want to made that the triangle abc takes the same shape that the cgf.
That is, see that the two walls, abdc and cdfg, are simetrical. The points a;b;c; f and g are flat while just d are high.
But GPL choice on one side of the simetrical arrange to join in a flat triangle cgf, as I like, but on the other side join acd, instead of abc.
I want a simetrical figure but I cant made it.
Again, with the vertices abcd, I want to made these two triangles: abc and bdc, but GPL choice to make these other differents two: abd and adc.
It is clear that the are two ways to join the triangles and GPL needs to choice just one of them.... but is only GPL who can choice the option or you can make something to be you who makes the choice?
Use two consecutives walls of the same type and with the shape of the triangle you want:
Edited by Luis Babboni, 12 May 2011 - 10:32 AM.