AFAIK (Dominique can correct me) SDL is compiling under FreePascal - pure multiplatform project.

GLScene is in process of trying to compile "itself" under FreePascal.

About half of Direc3D samples for Summer 2003 DirectX SDK on mine site can be compiled and run just fine under FreePascal. But during testing of new framework for 2004 release of DirectX SDK I've found that althrow I can compile it under FreePascal - projects fail to run correctly. Bugs were discovered in UNICODE support of FreePascal.