Method for rendering heightmap from a 3D scene I am looking for a method of rendering a heightmap from a 3D scene. The scene may consist of a terrain which is in turn generated from another heightmap, but will also have regular 3D objects.

The generated heightmap should, so to speak, indicate the highest point in the "column" of the 3D scene represented by each pixel in the heightmap.

This does not need to be a fast/realtime operation, and it does not really matter what language or library is used, although I'd prefer using Python (perhaps with Panda3D?). Also, I would prefer being able to run it headlessly, from a command-line tool without the need for an actual on-screen rendering.

Is this a common operation for which there are established/canonical methods, either through a library such as Panda3D or through more direct/low-level use of data structures representing the 3D scene?

I should add that I am quite new to the computer graphics field of programming.
Using OpenGL, or any such library, you could transform your scene with an orthogonal matrix and move your camera view point to be looking above (and parallel to) the scene (in a vertex shader) and then use an empty fragment shader which is going to write to the depth buffer of the current attached framebuffer. Finally retrieving this depth buffer gives you the heightmap of the current view.

If your scene is too big, you could move the camera higher and also move it around taking "chunks" of the map at a time and assembling your heightmap manually by "stitching" these "chunk" heightmaps together.

Hope this helps.