OSPRay v1.7.0

• Generalized texture interface to support more than classic 2D image
  textures, thus OSPTexture2D and ospNewTexture2D are now
  deprecated, use the new API call ospNewTexture("texture2d")
  instead
  • Added new volume texture type to visualize volume data on arbitrary
    geometry placed inside the volume
• Added new framebuffer channels OSP_FB_NORMAL and OSP_FB_ALBEDO
• Applications can get information about the progress of rendering the
  current frame, and optionally cancel it, by registering a callback
  function via ospSetProgressFunc()
• Lights are not tied to the renderer type, so a new function ospNewLight3()
  was introduced to implement this. Please convert all uses of ospNewLight()
  and/or ospNewLight2() to ospNewLight3()
• Added sheenTint parameter to Principled material
• Added baseNormal parameter to Principled material
• Added low-discrepancy sampling to path tracer
• The spp parameter on the renderer no longer supports values less than 1,
  instead applications should render to a separate, lower resolution
  frame buffer during interaction to achieve the same behavior