CS465 Program 5: Ray II

• assignment handout, v.3
• Parsing code
• Handy viewer window code
• Test Meshes
  • Buddha, 100k Triangles
  • Bunny, 10k Triangles
  • Bunny, 1k Triangles
  • Bunny, 500 Triangles

watch this space for additional helpful material.

FAQ

Check here for any updates to the Ray II description

• 4:00 pm, 29 November 2004: Do we have to support transformation of lights?
  A: No, you don't have to worry about this. As with the modeller assume all light sources are at the top level node.
• 4:00 pm, 29 November 2004: Are we allowed to pull code from the Ray 1 solution?
  A: Absolutely. There should still be more than enough challenge left.
• 10:45 pm, 20 November 2004: Version 2 of the handout gives a lot more detail about the file format you should use, and we are handing out a (necessarily incomplete) parser, based on the one in the previous assignment, which you can use as a starting point for your parser.
• 11:30 am, 23 November 2004: Version 2.1 of the handout includes some corrections:
  • input file keyword TriMesh changed to TriangleMesh.
  • parameter image added to camera
  • correction to syntax for materials (replaces color, rather than appearing after color)
  • added materials to mesh examples to make them correct
  And the parser is updated with some corrections:
  • camera parameter reading code streamlined and changed to match handout
• 11:30 am, 23 November 2004: What do I do if my input contains a surface of revolution but I'm not implementing surfaces of revolution?
  A: The general principle is, if the input is well-formed but contains anything you do not implement (surface types you don't support, parameter names your program does not recognize, etc.) you should safely and silently ignore it. For example, if your input file contains a triangle mesh and you don't support triangle meshes the result should be the same as if the triangle mesh was not in the file. Same goes for parameters: if you didn't implement area lights and you see an aperture parameter on a camera you should act as if the parameter was not there. You still need to be able to read and use a samples parameter that comes after the aperture, though.
• 12:15 pm, 23 November 2004: The parameters in the file for the camera don't match the parameters for the camera from the old ray tracer. Help!
  A: You're right. Some need to be converted and some ignored. You need to convert from height to vertical FOV (assume an image plane distance of 1). You should ignore the aspect ratio and let it be instead determined by the image size.
• 2:00 pm, 26 November 2004: We have posted the code for RayViewer, a helpful replacement for RayTracer.main that shows you the progress of rendering in a window. This makes waiting for renderings more fun. Its interface with the rest of the program is simple and it should be easy to adapt it to your needs.
• 5:00 pm, 2 Decmber 2004: If you implement the AABB hierarchy, you will need to get rid of your transformation hierarchy first. That is, you need to flatten the tree and concatenate the transformations for each individual object. Then, once you have a single list, you can build the bounding box tree exactly along the lines of Shirley's Chapter 9.
• 11:30 am, 3 Decmber 2004: Is it really true that I can only have letters in my filenames for triangle meshes?
  A: Here is a version of Ray2Reader.parseToken that supports quoted strings like this: TriangleMesh ["Nice (long) filename!.msh" (0.5, 0.5, 0.5)] The file Ray2Reader.java linked to this page is also updated with this change.