View Full Version : Exposure of photometric lights

02 February 2009, 08:24 PM
I can't seem to find a way to set the type of ex/inclusion for the exlusion or inclusion of objects for photometric lights.

default max pointlights expose: "$.inclExclType" there seems to be no such property for a photometric light, although you can access the in/exclude object list... please someone tell me I'm wrong and I missed the obvious!


02 February 2009, 09:58 PM
nope - didn't miss anything obvious.

The only thing you need to know is that when you -set- .includeList = #(<nodes>), the mode switches to include. If you -set- .excludeList = #(<nodes>), the mode switches to exclude. And if you need to know what mode it's currently in, it's whichever list returns an array (the other will return 'undefined'). If you need to switch modes...

if ($.excludeList == undefined) then (
$.excludeList = $.includeList
else (
$.includeList = $.excludeList

02 February 2009, 10:20 PM
Yeah I got that part figured out, but I need to know in which mode it is, light/shadow etc...crap...whyyyyyy.... what a day...


02 February 2009, 11:37 PM

02 February 2009, 07:51 AM

02 February 2009, 08:32 AM
oie.. too early for UIaccessor stuff..

completely non-cleaned-up (mm, globals) and non-commented, but should do as the function name advertises..

global BM_GETCHECK = 0x00F0
global photometricIEmode = undefined
dialogMonitorOPS.UnRegisterNotification id:#getPhotometricIEmode
dialogMonitorOps.enabled = false

-- get the Include.../Exclude... button from a selected Photometric light with the Modify panel active
fn getPhotometricIEbutton = (
local maxHWND = windows.getMaxHWND()
local maxChildren = windows.getChildrenHWND maxHWND

local foundTab = false
local foundPanel = false
for child in maxChildren do (
if (child[4] == "ModifyTask") then (
foundTab = true
if (foundTab) then (
if (child[4] == "RollupPanelTitle") then (
if (child[5] == "General Parameters") then (
foundPanel = true

if (foundPanel) then (
if (child[5] == "Light Distribution (Type)") then ( exit )
else if (child[5] == "Include...") OR (child[5] == "Exclude...") then (
return child[1]
return undefined

fn getPhotometricIEmodeMon = (
local dlg_hwnd = DialogMonitorOPS.GetWindowHandle() -- check the dialog that popped up
local dlg_title = UIAccessor.GetWindowText dlg_hwnd
if (dlg_title == "Exclude/Include") then ( -- the obj export config dialog
local controls = windows.getChildrenHWND dlg_hwnd -- get all controls for this dialog
for c in controls do (
if (c[5] == "Illumination") then (
local c_hwnd = c[1]
c_state = windows.sendMessage c_hwnd BM_GETCHECK 0 0
if (c_state == 1) then (
photometricIEmode = #illumination
UIAccessor.pressButtonByName dlg_hwnd "OK"
return true
else if (c[5] == "Shadow Casting") then (
c_hwnd = c[1]
local c_state = windows.sendMessage c_hwnd BM_GETCHECK 0 0
if (c_state == 1) then (
photometricIEmode = #shadow
UIAccessor.pressButtonByName dlg_hwnd "OK"
return true
) -- for c in controls
photometricIEmode = #both
UIAccessor.pressButtonByName dlg_hwnd "OK"
) -- hwnd_title == "OBJ Export Options"

fn getPhotometricIEmode l = (
photometricIEmode = #error
local oldSel = getCurrentSelection()
local oldTask = getCommandPanelTaskMode()
select l
max modify mode
local IEbutton = getPhotometricIEbutton()
if (IEbutton == undefined) do ( return false )
dialogMonitorOPS.RegisterNotification getPhotometricIEmodeMon id:#getPhotometricIEmode
dialogMonitorOps.enabled = true -- enable the monitor
UIAccessor.pressButton IEbutton
setCommandPanelTaskMode oldTask
dialogMonitorOps.enabled = false -- disable the monitor
dialogMonitorOPS.UnRegisterNotification id:#getPhotometricIEmode
select oldSel

<name>getPhotometricIEmode <photometriclight>
possible return values:
#error -- something went wrong.. probably not a photometric light?
#illumination -- exactly what you'd expect it to mean
#shadow -- yup
#both -- indeed

edit: #test -> #getPhotometricIEmode

02 February 2009, 09:11 AM
You just couldn't resist right ;)

Thanks man, I will look into it, but we just had a "technical meeting" and decided that for our current project we are ditching all photometric lighting in favor of point lights, not because of this issue though, but my tool only has to handle pointlights for now....
Our environments are so large that we are taking the pointlight "light energy everywhere" instead of the cool realistic fallofs of photometric lights.

I will look at the code and try to implement it and see if works for the skydome approach we're using.


02 February 2009, 09:44 AM
had to try :p

photometric lights are just glorified regular ol' lights anyway. the temperature control is just a filter on top of a regular color, the photometric units are just multipliers on top of the regular multiplier, etc. The only 'special' thing is the whole photometric web which, if you were so inclined and point lights weren't stupid*, you could render out to a lat/long bitmap and use as a projector.

* point lights handle projectors as if the light is actually 6 lights, each illuminating a face of a cube *sigh* so you have to opacity-map it to geometry and have the light use raytraced shadows and argh.

Anyway - good luck :)

02 February 2009, 10:05 AM
But I'm correct if I say that photometric lights always have falloff, right, I don't need that I have huge environments and objects moving through it should be constantly lit, like if all lights where suns. I'm pretty comfortable *I think*, with using photometric for closed environments and daylight for outdoor scenes, but I'm in outer space and some other dimensions too, that require a different approach, I want to be able to use low intensity ambient light with different colors from different angles and some suns casting shadow.
Am I right thinking photometric lights cannot give me that and I need a more old school approach?

I'm interested in the lat/long bitmap, could you maybe explain a bit more what you mean, I'm not really following :blush:


02 February 2009, 02:19 PM
they have an inverse square decay set up by default, yes - nothing you can't do with regular ol' lights

as for the lat/long bit - that was just me mumbling :)
An IES web file, for most common lights, defines a series of angles at which lighting is sampled for the light in question, and the intensity of the light at that angle. A lat/long image - like many HDR images - could contain fairly much the same information; won't do you any good, though, as point/omni projector lights are funky =)

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