Jump to content
  • Advertisement
Sign in to follow this  
Skiz0

SH/Irradiance/D3DXSHProjectCubeMap problem

This topic is 3816 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

I have been working with Spherical Harmonic / Irradiance for more than a week now, and some help would be highly appreciated! What I am trying to do is to generate the matrix M to represent an Irradiance environment maps (http:www.csie.ntu.edu.tw/~cyy/courses/rendering/07fall/lectures/handouts/lec15_SH.ppt) To generate the 9 coefficients per channel (using order 2), I generate a cube map and compute the SH coefs using D3DXSHProjectCubeMap. For debugging purpose, I set +X face to red and all the other ones to black. D3DXSHProjectCubeMap returns these 9 coefs for the red channel: 0.590712f, -0.000000f, 0.000000f, -0.850431f, 0.000000f, 0.000000f, -0.364121f, 0.000000f, 0.630666f What should the matrix look like? I tried this one c1L22 c1L2−2 c1L21 c2L11 c1L2−2 −c1L22 c1L2−1 c2L1−1 c1L21 c1L2−1 c3L20 c2L10 c2L11 c2L1−1 c2L10 c4L00−c5L20 from: http://www.cs.columbia.edu/cg/pdfs/60_envmap.pdf , with constants: c1 = 0.429043; c2 = 0.511664; c3 = 0.743125; c4 = 0.886227; c5 = 0.247708; but doesn't seem to work. If I try with normal (-1, 0, 0), the value should be 0 (as -X face is black) but I still get a value higher than 0 (0.7 something) Any help on what the matrix should look like working with value output from D3DXSHProjectCubeMap would be highly appreciated! Thanks. [Edited by - Skiz0 on July 7, 2008 8:56:14 PM]

Share this post


Link to post
Share on other sites
Advertisement
Sign in to follow this  

  • Advertisement
×

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

GameDev.net is your game development community. Create an account for your GameDev Portfolio and participate in the largest developer community in the games industry.

Sign me up!