Mouse + BoxBoundProbe

Look at the Pick sample included with the SDK. It does exactly what you are talking about.

Okay

The problem is I''m using C#, so I''m not really used to C++ code, especially direct X code, but I will have a look at it and if I can''t figure it out I will come back here and weep.

/Johan

I have had a look at the C++ code now and would like, if possible, get this confirmed before I try to implement it.

1) Get the projection matrix
2) Create a vector using the mouse position and projection matrix
3) Invert the view matrix
4) Use the inverted view matrix to calculate where the click is in 3d space
5) Create the ray and see what it hits

Is this correct? One thing seems really odd to me, when calculating the ray in the pick sample this formula is used:

// Transform the screen space pick ray into 3D space
// v is the vector for the click and m is the inverted view matrix
vPickRayDir.x = v.x*m._11 + v.y*m._21 + v.z*m._31;
vPickRayDir.y = v.x*m._12 + v.y*m._22 + v.z*m._32;
vPickRayDir.z = v.x*m._13 + v.y*m._23 + v.z*m._33;
vPickRayOrig.x = m._41;
vPickRayOrig.y = m._42;
vPickRayOrig.z = m._43;

Should it not be the other way around? Should not the origin be calculated using the click and the direction directly calculated from the inverted view matrix?

/Johan