There are many hundreds of changes that have been made to the source code since version 3.5 was released. However since version 3.6 concentrates on improving stability and providing a framework for a future re-implementation of POV-Ray, most of these are invisible to the end user. However, here is a short list of some of the more notable changes.

• Core changes (all platforms)
• Windows platform changes
• Macintosh platform changes
• Unix/Linux platform changes (full list)

• Several improvements, extensions and corrections
• New design, availability in printable form

• Superellipsoid speedup (Change 1937)
• UV-mapping for parametric and torus (Change 1937, 1991)
• Density file support for 16 and 32 bit integer data (Change 1937)
• Sphere_sweep bugfix (Change 1965)
• Render time display bugfix (Change 2023)
• Blob artifacts bugfix (Change 2022)
• Photon speed improvements (Change 1937, 2037)
• IOR bugfix (Change 2052)
• Unclipped radiosity values (Change 2053)
• True 16 bit png support for image_maps (Change 2076)
• Torus accuracy problem fix (Change 2182)
• 16 bit binary ppm/pgm support and buxfixes for ppm/pgm (Change 2186)
• Redesign of text message output
• Numerous small bux fixes

For a more comprehensive list of changes to the Unix/Linux platform see this page.

• New format of io-restrictions configuration file
• Several fixes in X11 display
• Improved install script (binary version only)
• Completely reworked build system (source version only)

• Added support of new communication infrastructure for getting/setting core options
• Moved renderer into its own thread
• Make it possible to run pvengine.exe without pre-defined registry settings
• Support for reading 32bpp BMP images containing alpha channel
• Numerous minor GUI and editor fixes and improvements
• Miscellaneous bug fixes