Wednesday, 3 April 2013

Splay Normals

Foliage models often require edited normals. There are already normal-splaying scripts out there but I wanted to be able to set a position and use a strength value to effectively splay them partly from the centre of the "bush", and partly from the branch or trunk. I also wanted to be able to splay only the selected verts. This is the result.

  • Position the working pivot
  • optionally select some of the verts (if none selected, will select all)
  • optionally set strength to a value like 0.4
  • run script

-- MixeScript snippet: SplayNormals
-- Splays selected normals away from the working pivot

-- Position the working pivot
-- select some or all of the verts (if none selected, will select all)
-- optionally set strength to a value like 0.4
-- run script
Strength = 1.0 -- when set to 1.0, entirely replaces existing normal direction. at 0.0, does not adjust normal at all.

max modify mode
obj = $
modPanel.setCurrentObject obj
enMods = (for m in obj.modifiers where classof m == editnormals collect m)
enMod = enMods[1]
subobjectLevel = 1 --verts 
vertarray = #{}
vertarray = polyop.getVertSelection obj
if vertarray.numberSet == 0 then -- no selection, select all
 polyop.setVertSelection obj #all
 vertarray = polyop.getVertSelection obj

if enMod == undefined then
 enMod = editnormals()
 modPanel.addModToSelection (enMod) ui:on

WPTM = WorkingPivot.getTM()
splayfrom = (WPTM[4])
modPanel.setCurrentObject obj

normarray = enMod.GetSelection()
--enMod.MakeExplicit ()
objpos = obj.pos

modPanel.setCurrentObject enMod
for vert in vertarray do (
 vertpos = (enMod.GetVertex vert node:obj) + objpos
 newnormangle = normalize (vertpos - splayfrom)
 tempbitarray = #{vert}
 norms = #{}
 enMod.ConvertVertexSelection tempbitarray norms
 enMod.MakeExplicit selection:norms
 for norm in norms do 
  existingnormangle = normalize (enMod.GetNormal (norm))
  finalangle = normalize ( newnormangle * Strength + existingnormangle * (1 - Strength))
  enMod.SetNormal norm finalangle


  1. Could you further explain what this would be used for Mike.

  2. hey, sorry man, was away today. take a look at this page and it should all become a bit more obvious heh...

  3. can you tell me how to get data from serial or usb port with maxscript?
    i have a avr micro controller and it sends data through a USB serial port and i want to get data in maxscript for my collage project.
    please tell me how.
    do you know how to use sdk in visual studio?

  4. Pretty great script! Would there be any way to extend its potential to non Editable Poly objects? I'm oh so fishy on how to do that kinds of stuff (say a primite with a Turn To Poly modifier or so on top - or more complicated things)..