# Draw a point in world coordinate space

How do I draw a point in world coordinate space (where the camera is currently looking at, so that would be view*projection correct?)

I would think I would need to do something like:

PositionInWorld = MousePositionInNDC * view * projection?

• Your secondary question about vertex buffers is entirely separate and should be asked on its own; note also that we don't consider questions that are just asking for links to resources to be on-topic, as they're lists and broad (you may want to ask that on GDNet, or alternatively ask here about the specific issue you're having. – Josh Nov 30 '16 at 17:49

## 1 Answer

If you want exactly in the center of the camera's field of view, then what you can do is to take a 3d vector pointing in the monitor (aka. (0; 0; -1)), create a 3x3 rotation matrix with the same angles your camera has and multiply these together, this results in a 3d vector rotated to match the camera's ditection. To get a point x distance from the camera, you multiply this vector with x and you add it to the camera's position.

If you only have access to 4x4 matrices (for example if you use unity), then do everything as above but with a 4d vector and a 4x4 matrix, and before you add the vector to the camera's position, downgrade it to a 3d vector.