Hi, i'm trying to implement the tone mapping algorithm used in radiance. looking at the source code of radiance (color.h), it calculates the luminance as: Luminance(col) = WHITEEFFICACY * bright(col); where bright(col) is the y chromacicity component and WHITEEFFICACY = 179.0; i'm trying to figure out where that value comes from, i would expect it to be 683.0 wich is the maximum efficacy (reached for 555nm wavelenghts). does anybody have any idea how this value (179) was calculated? thanks.
white efficacy in radiance
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Hi: I am working on a CAFM project in AutoCAD system. right now I have problem relate to polygon. 1. island (hole) detect: How I can detect if a island (hole) of a polygon, inside or outside ? This is general example: ---------------------- | | | ------------- | | | | | | | | | | | | | | |------------- | | | | | | | ---------------------- also I need to check if this is self intersect, how I can do this? 2. polygon offset: for any 2 adjace polygon, there are 3 situation there: Polygon A take all space, polygon B take none; A and B take 50% B take all, A take none I am not going work with ARC segment right now. If you give any direction, algorithm, code sample, reference site, I will really appreciate it. Thank you very much Happy Valentine's Day Wes - 2. *why* are rational beziers projective-invariant?
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white efficacy in radiance
by dolphin_24 » Thu, 17 Mar 2005 09:24:10 GMT
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