3D World Studio

From Leadwerks:

3D World Studio by Leadwerks is a constructive solid geometry (CSG) modeler with support for object placement, terrain, and lighting. The program is used by thousands of architects, game developers, interior designers, and hobbyists around the world to produce 3D walkthroughs, games, and simulations.

Version 5.52 provides: fast object manipulation and drawing, designed for efficiency; select and texture objects or object faces; stretch, position, mirror, flip, and rotate meshes; automatic UV mapping; UV mapping tools, including justify and fit to face; CSG operations include carve, hollow, split, and extrude face. Some other features include: configurable entity system; adjustable viewports; accurate grid snap; draw selection boxes; export to .x, .map, .wmp, .dbo, .b3d, or .dif; browse meshes by thumbnails; manage and browse thousands of textures and meshes; new brush primitives including arches and tubes. View detailed statistical information including polycounts broken down by object type. Some Mesh, Lighting, and Terrain Features were also added.

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