Globe 3D

GLOBE_3D is a free, open-source, real-time 3D Engine written in Ada, based on OpenGL.

Unconditionally portable sources (one set of sources for all platforms)
Real-time rendering; fast with a 3D hardware-accelerated graphics card
Full eye movements and rotations
Displays combinations of colours, materials, textures
Transparency
Multiple area rendering with the portal technique, e.g. for inner scenes
Collision detection
Binary space partition (BSP)
Input-output of 3D objects or groups of objects linked to each other by portals
Easy management of resources like textures (.bmp, .tga), BSP trees and objects stored in .zip files
Screenshots (.bmp) and video captures (.avi)
Multi-view support
Vectorized geometry support