So I want to path trace a Cornel Box scene, but I don't understand the values given here in section 2 and 3.

Cornell Box Data | Cornell University Program of Computer Graphics

No.2 Lists surface reflectances with respect to different wavelengths but I'm not using wavelengths. I thought this was done in spectral path/ray tracing where we are using photometry instead of radiometry.

Similarly No.3 lists Light properties though I don't understand what do the values in the light column (0, 8, 15.6, 18.4) suggest.

I was merely expecting the specular and diffuse reflectivity in all 3 channels for each of the colors red, green and white.

  • $\begingroup$ You could take a sample at the RED/GREEN/BLUE wavelengths from the table to make a rough RGB for the White/Green/Red materials. $\endgroup$ – PaulHK Aug 14 '18 at 7:20
  • $\begingroup$ @PaulHK - if i understand correct, you mean i should pick 3 wavelengths values from table 2 corresponding to each of the R/G/B. Then i should pick the reflectance values corresponding to them to get my RGB color for each of the white red and green columns? I could do that but I'm actually writing a general interface using Assimp which loads obj/ply files and reads info from them. Isn't this approach valid for only this particular case? I couldn't find a .obj format for cornell box. Is there any other way? $\endgroup$ – gallickgunner Aug 14 '18 at 7:35
  • $\begingroup$ It looks like this version of the Cornell box is used to validate spectral tracers and was derived from real world observations $\endgroup$ – PaulHK Aug 14 '18 at 8:22
  • $\begingroup$ would the one from POVRay be any use ? github.com/POV-Ray/povray/blob/master/distribution/scenes/… $\endgroup$ – PaulHK Aug 14 '18 at 8:25
  • $\begingroup$ Hmm, ok are there any other similar models or some other ways I could check first to see If my path tracer is converging correct or not? I was actually interested in comparing my render of cornell box to the iamges provided in that link. But since they are for spectral tracers, is there something similar for non spectral ones? $\endgroup$ – gallickgunner Aug 14 '18 at 8:29

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