Hi
i am trying to create an expression in Xgen to drive the direction of the primitives based off of a normal map. the method is based off the example "grow in an exact direction" at the bottom of this page
https://knowledge.autodesk.com/support/maya/learn-explore/caas/CloudHelp/cloudhelp/2020/ENU/Maya-Cha...
i have everything working but for the life of me i cannot extract the individual channel data from the normal map. I would like to use the red channel for the X vector and the green channel for the Y. In the Xgen reference the syntax is stated as follows:
map( "mapname" [,s, t] [, channel] )
however my scripting knowledge isn't amazing I keep getting a syntax error, right now i have converted the red and green channels from my normal map into 2 grayscale images with Photoshop and loaded them in individually, it works fine but it is a bit messy. So far my expression is as follows but i would like to just use one RGB map and just extract the channels into my vectors if possible
$r=map('${DESC}/paintmaps/custom_vector_dir');#3dpaint,100.0
$g=map('${DESC}/paintmaps/custom_vector_dir2');#3dpaint,100.0
$vector_multiplier = 0.1000; #0.00,1
$randomness = 0.0500; #0.00,1
$randvalue = rand(($randomness * -1), $randomness);
$x=($r - 0.5) * ($vector_multiplier + $randvalue);
$y=($g - 0.5) * -1 * ($vector_multiplier + $randvalue);
norm([$x, $y, 1])
if someone could show me how to get the channels from the RGB normal map that would be greatly appreciated, thank you
