Hi I guess my question is simple but i can not find the answer How do the three matrices ( world matrix, view matrix , projection matrix ) work ? I am not talking about math here. my idea is that if i draw a triangle before using any of these three matrices and then use as a first step world matrix, will this triangle look different and how ? and by adding another matrix (view matrix), how different will be again ? i think what i am trying to know is what these matrices really do. I read what microsoft wrote but that was not enough for me to understand thanks for help

Buy a book on 3D graphics (Computer Graphics Using Open GL by Hill is a good one), or google for 3D graphics, 3D pipeline, etc.

In a nutshell, your world matrix will place your triangle in the "world" at some position and orientation. If you created 10 triangles and didn't apply any world matrix to any of them, they would all be in the same space overlapping each other - you would see 1 triangle.

The view matrix is essentially the camera matrix. It is the angle/orientation that your camera is looking at the entire scene. All objects in the scene will be transformed by this, so it will appear as if you are looking in a certain direction.

The projection matrix is needed, because you are viewing this 'camera view' on a 2d surface (your monitor). 2 common ways to view the scene are perspective and orthoganal.

This is fundamental 3D graphics stuff that you really need to know. Pick up a good book on this topic, as my post hardly does it justice.

Also the world matrix can be used for more than just translation it can be used for rotation and scaling to.

The view matrix is pretty much a camera. You can set its camera position, Lookat point and up vector. These all determine how your 3D world will look.

And for the projection matrix, its like the lens of the camera.

Double post.