"stitched" style panorama in Blender? (NOT equirectangular)

Question

I'm looking for a quick solution to creating curvilinear perspective renderings in Blender. Specifically, I want the kind of panorama you'd get if you shot a panorama on a camera or were drawing a wide-angle drawing of what's around you, turning your head.

Rob Adams has good examples of the goal here: http://www.treeshark.com/treeblog/?p=301

Equirectangular is close but it seems to be designed to keep vertical lines straight. I'm looking for curvature on both vertical and horizontal lines.

Has anyone done this? I'd prefer to avoid doing this the hard way, stitching together renders into a panorama. A script could do that, I'm sure, but even that would be somewhat clunky in terms of interactivity.

Answer 1

If you want a spherical perspective as your link suggests, then fisheye equisolid is the type of camera you want to use. You can find it by activating the Cycles render engine, then selecting Panoramic in the Camera type and then Fisheye Equisolid in the panorama type.

You can also do it the "post-prod" way by first rendering using a rectilinear camera (called "Perspective" in Blender) because it renders faster and has a 1 on 1 correspondence with your viewport, and then use the "Lens distortion" node in the compositor. However, this one gives an elliptical distortion if your image is a rectangle (just like a Fisheye Equidistant camera). You'd have to set up a node tree to get the real spherical distortion. It could be done using a displacement node; some gradient textures and some math nodes, but you may get some subtle sub-pixel artifacts due to discontinuities in the gradient texture node. My web search didn't give me any result for someone who already set up a node tree for that particular projection but maybe I missed it.

Answer 2

The easiest solution is to render your movie with "normal" lens to a video file, then get its output you can project like a texture on other object and have any kind of deformation / lens you like.