Render-Boy 2.3 for Mac is free to download from our software library. The application lies within Design & Photo Tools, more precisely General.
From the developer:
RenderBoy allows you to easily model and render photo-realistic 3D images and animations, complete with shadows, reflections, refractions, textures, and more. New features include an improved menu layout, a tool palette for frequently used functions, drag&drop rendering of multiple designs, improved animation capabilities, and a new triangular prism object.
You may want to check out more software for Mac, such as Mac Journal, Start FlowSpace Developer Client or Architekt 3D Gartendesigner, which might be similar to Render-Boy.