D3d start

Explanation
When making games in 3D, some things are different. Normally, the room is viewed from a top view. In 3D mode, the room is viewed from the left side. You can also change the projection with d3d_set_projection.

Note that d3d_set_hidden and d3d_set_perspective are enabled by default.

Remarks
Some of Game Maker's features that work in 2D don't work in 3D mode:
 * Particles
 * Surfaces