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View Full Version : Addaptive Subdivision??



sammael
08-26-2006, 03:45 AM
I wonder if someone could explain the basic principles and practice of using gradients and greyscale images to control the subdivision of an object?.
I have watched the LW9 video on the topic but I dont understand exactly how it works.
I have set up my images exactly the same as in the video, but some of the detailed white areas in my image are barely subdivided at all. The confusing thing is that some of the detailed white areas are subdivided sufficiently. To my understanding it should be all or nothing, not some subdivided some not.
:foreheads
I dont know maybe its buggy because originally when I started working on the file it seemed to work fine but at some point when I have made alterations to my map it stopped working fine. :compbeati :compbeati :compbeati

I have a high and low value of 50 and a mid value of 3.

sammael
08-26-2006, 11:58 PM
Here is an image of my APS setup. in the green area the APS is working properly, in the red area it doesnt seem to work at all. On the actual image map the veins on the arms are drawn exactly the same as the ones on the legs.

DragonFist
08-27-2006, 02:00 AM
You're using the displacement map to run the subdivision level. Which is fine but I can't see if you also have it under the displacement for those areas. If not, it would be you're problem.

sammael
08-27-2006, 02:22 AM
DragonFist - Yeah im using the same image for the displacement as i am for the APS.
Its so wierd, at first it seemed to work, but now it only works in some areas I just cant understand why it works in some places but not others?? WTF??

It would be nice if one day you could just make something in lightwave without getting completely stuck on something for days trying to work out what the problem is, particularly when 'trying to use' displacement.... (keeps on dreaming)

DragonFist
08-27-2006, 02:47 AM
Another point is that you have the main value set at 3 but higher values in the texture. According to one video, the main number sets the highest value so your texture will cap at subdivision level 3.

sammael
08-27-2006, 03:17 AM
DragonFist, I just tried changing the value to 35 same as the max APS in the gradient. It made no diference, it seems that the APS settings override this value.

DragonFist
08-27-2006, 04:02 AM
Sorry, wish I could be of more help.

How about something with the gradient? Does an image map give a value between 0 and 1 or does it give a 0-255 value?

Edit: Also, do you have mip mapping turned off for the image, I find it messes with displacement maps.

sammael
08-27-2006, 04:39 AM
Yeah im not sure exactly how the gradient interacts with the image, I was hoping someone could explain it to me.
Thanks for the tip with the mipmapping ill turn that off and let you know if it made a diference.

sammael
08-27-2006, 09:04 AM
no change when i turn off mipmapping but now i have sort of corrupt looking bright areas on my model after changing absolutley nothing! :cursin: