Announcement

Collapse
No announcement yet.

Lets make Lightmass EPIC (and understandable)

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • replied
    Originally posted by PDantas View Post
    Hi guys! Been following this thread for a while, and got amazing insights here on how to work the lightmass.
    Nonetheless my adition is not so magnanimous.

    I'm having some blotches showing up after the bake and I can't figure out why. Increased lightmap resolution, verified UV's, baked in production, but I'm still stuck with same problem.

    Everything else seems to be ok (light is too strong and burning quite a lot)!

    It's strange cause I already used this model in previous works and never had this problem. Also the wall should be complanar and the shadow much smaller.

    [ATTACH=CONFIG]109930[/ATTACH]

    Is this due to indirect shadow?

    I'm guessing a bit here but if the gap is too big and the shadow from the gap over the door is bleeding around to the wall then it's most likely that you haven't separated the polygons inside the gap from the wall polygons. Maybe this image helps (I made it a while ago for unreal 3 but it is still valid)
    Click image for larger version

Name:	shadow-bleeding2.png
Views:	1
Size:	13.2 KB
ID:	1115476

    For the couches: We always have these problems with old high poly objects. It is really hard to make a good lightmap for a high poly object. Best is often to just bake a new low poly object off the high poly old vray asset.

    Despite the general problems it might just be that your lightmap resolution is too low for the couch and the shadow is bleeding from one uv chart to another. (a too low lightmap resolution could also be caused by texture streaming issues but the scene seems to be small and not having any streaming issues.) Unreal is pretty good in rearranging the lightmap uv's. You could try to reshuffle the uv charts in the mesh browser (built settings just after the material section). Use 1 as source and target uv channel, set the minimum resolution to maybe 128 or 256 and hit "apply". Then make sure you increase the lightmap resolution further down in the static mesh settings as well.

    Leave a comment:


  • replied
    thanks so much

    Leave a comment:


  • replied
    Originally posted by Casandez View Post


    links broken, where i can get it?

    thanks.
    Click image for larger version

Name:	Onlyskylight3.jpg
Views:	2
Size:	313.1 KB
ID:	1115451



    GoogleDrive
    https://docs.google.com/uc?id=0B3wYK...xport=download

    Dropbox
    https://www.dropbox.com/s/0ljra2l3h0...dNaji.zip?dl=0

    Microsoft OneDrive
    https://1drv.ms/u/s!Ar7INFDcXdscgnWMCXW4AKFmf0Sa

    Mediafire
    http://www.mediafire.com/download/9x...arshidNaji.zip

    4shared
    http://www.4shared.com/zip/8ARByBcice/FarshidNaji.html

    Uptobox
    http://uptobox.com/s6m3icy2uknu
    Last edited by Farshid; 09-15-2016, 02:47 PM.

    Leave a comment:


  • replied
    No, no flickering. And I verified the uv's and ther all correct. I adjusted the light and the result improved a little with the shadows getting softer. It seems to have improved.

    Thanks nonetheless

    Leave a comment:


  • replied
    Could be overlapping uv's or a too low memory streaming pool. Do you get flickering shadows on that couch when you move around the scene?

    Leave a comment:


  • replied
    Hi guys! Been following this thread for a while, and got amazing insights here on how to work the lightmass.
    Nonetheless my adition is not so magnanimous.

    I'm having some blotches showing up after the bake and I can't figure out why. Increased lightmap resolution, verified UV's, baked in production, but I'm still stuck with same problem.

    Everything else seems to be ok (light is too strong and burning quite a lot)!

    It's strange cause I already used this model in previous works and never had this problem. Also the wall should be complanar and the shadow much smaller.

    Click image for larger version

Name:	ShadowErrorUE4.13.JPG
Views:	1
Size:	146.8 KB
ID:	1115043

    Is this due to indirect shadow?

    Leave a comment:


  • replied
    Originally posted by Casandez View Post
    Scene: https://mega.nz/#!rtQ3XLzT!7BR5v95YW...uFEJHDxljR_jqM

    File BaseLightmass.ini: https://mega.nz/#!n5xGSLiT!ZmOMwf69N...Krv6KTkfp9WfJU



    links broken, where i can get it?

    thanks.
    same question [MENTION=37103]Raghu[/MENTION]

    Leave a comment:


  • replied
    I wish they'd add more control of portals, more along the line of mental ray/arnold .

    Leave a comment:


  • replied
    links broken

    Scene: https://mega.nz/#!rtQ3XLzT!7BR5v95YW...uFEJHDxljR_jqM

    File BaseLightmass.ini: https://mega.nz/#!n5xGSLiT!ZmOMwf69N...Krv6KTkfp9WfJU



    links broken, where i can get it?

    thanks.

    Leave a comment:


  • replied
    Epic is well aware of GPU rendering as an option for lighmass, but there's some likely issues

    1. Epic would have to re-write lightmass from scratch.
    2. Results might not be as high quality (people already complain a lot about lightmass and seams).
    3. You probably couldn't work in the editor while baking using the GPU.
    4. The editor/GPU lightmass wouldn't scale well for lower end machines.

    They might get around to it eventually, but if reasonable settings you can get a decent lighmass bake pretty quick. The Lightroom: Interior Day Light by Koola example scene bakes in about 5 minutes for me.

    Leave a comment:


  • replied
    Maybe a little bit offtopic, but why is lightmass rendering not executed on the GPU?? I thought GPUs are designed to perform graphical tasks like GI? Coming from Blender and even there you render on the GPU (and by the way much faster than on a CPU)

    Leave a comment:


  • replied
    Thank you for this thread, so much info to digest.
    I have a problem though when I try to bake one of test scenes posted here: the Swarm Agent log shows something not very promising:

    21:32:42: Couldn't gather the requested number of indirect photon paths! 0 gathered
    21:32:42: EmitDirectPhotons complete, 0.000 million photons emitted in 0.1 seconds
    21:32:42: EmitIndirectPhotons complete, 0.000 million photons emitted in 0.1 seconds
    21:32:42: Marking Irradiance Photons complete, 0.000 million photons marked in 0.1 seconds

    Sometimes it bakes and sometimes not and it just fails.
    Does anyone know why it can happen?
    4.12.5, gtx 680, 64gb ram
    Last edited by Luckyfox; 07-29-2016, 02:26 PM.

    Leave a comment:


  • replied
    Hi ZacD, yes lightmap compression is off already, thanks! I'll search for that forum post

    Leave a comment:


  • replied
    Well, 1024 is 16x more pixels than 256. Some banding in dark places is normal, make sure light map compression is turned off, if it isn't already. There's a forum post about how to deal with light mapping curtains, I'll have to look for it, there's some tricks to it.

    Leave a comment:


  • replied
    Hi Guys,

    I'm studying UE4 right now following all what I read in the forum and the documentation, I'm kinda stuck with the "lightmass or shadow" problem of mine.

    Here's a screen shot of a test scene

    Shadow or lightmass detail is not good in the curtain..
    Click image for larger version

Name:	Test_13.jpg
Views:	1
Size:	90.8 KB
ID:	1112045

    light map res for the curtain and all the walls are at 1024, I tried earlier with the curtain at 256 with a build time at 5mins, and the attached one with the 1024 which ended at 30mins T_T
    baselightmass.ini are at default and the lightmass settings are .25 / 8 / 4 / 1.1

    How can I fix the shadow issue? And also at the back wall I'm having a bit of grey scale banding, is that normal with the lightmass current settings and a dim lighting?
    Click image for larger version

Name:	banding.JPG
Views:	1
Size:	26.1 KB
ID:	1112046

    Thanks! You guys rock! \m/

    Leave a comment:

Working...
X