Picking

This lesson covers performing picking in 3D.

Ray casting

You can find an older tutorial on 3D picking using ray/object tests at Rastertek that uses the deprecated D3DXMath library. Note that instead of a 'roll your own' RaySphereIntersect you can use BoundingSphere from DirectXCollision.h with the following method to do the ray-sphere test:

bool Intersects(FXMVECTOR Origin, FXMVECTOR Direction, float& Dist) const;

Also remember that the default view coordinates for DirectX Tool Kit is "right-handed" viewing coordinates and the Rastertek tutorials follow the older DirectX style of "left-handed" viewing coordinates. This requires reversing the Z direction of the ray.

Next lesson: Mixing SimpleMath and DirectXMath

Further reading

DirectMath Programmer's Guide
DirectXMath Collision sample