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View Full Version : adaptive subdivision (APS) problem with LW11.6.1



vipvip242
12-23-2013, 06:24 AM
I experience problems with adaptive subdivision:

i followed the method discribe here :

http://www.axisorigin.com/lwtutorials/aps/

in fact, it works for small values ( ie 6.0 for 100% weight value ) but when i make grow the value of the 100% weight map gradient ( the one which controls the APS ), it refines too the polygons which normaly shouldstay at level 1.0 of subdivision...

Does anyone have an idea ?

or is it a bug ?

BigHache
12-23-2013, 10:47 AM
118875

This worked as described for me. To note, this is visible only in the render not in the viewport, as the Per Polygon Level Texture is only available in Render SubPatch.

Fun technique!

vipvip242
12-23-2013, 10:57 AM
Thanks for testing.
Indeed, it works only with F9/F10 render, that's what i've tested before.
But did you succeed in having a very high density of polygons for the weights values of 1.0 ( defined by the APS gradient ) and a very few poly-density for the gradient value 0 ?
me not :/
As i've explained before, it is working for me too, but not with the conditions described on previous line.
the interest of this technique is to have a great displacement resolution on big surfaces without consuming too much ram/time...

the picture you've posted is exactly what i want to reach but i can't get such a densities, is it done by youself or coming from the tutorial ?

BigHache
12-23-2013, 11:10 AM
I just now went through the tutorial and produced that image. Here's my scene file if it helps.

118876

vipvip242
12-23-2013, 11:14 AM
thanks a lot !

vipvip242
12-23-2013, 12:04 PM
Hi again

just tested and it works for me too, but the problematic remains the same: the more the +100% value is high ( like 12 or more ) and the more itr subdivise the polys which normaly are with a weight of 0% ( attached a packed scene with higher values and a screen capture to explain the problematic ).
Anyway, even in this case, we have a great gain of polygons
Thanks again for your help

BigHache
12-24-2013, 08:37 PM
This makes sense. The higher the poly count at the high point, the longer it will take to reduce polys to the low point. Take a look at this:

118890

This is from your scene, from the opposite side of the deformation. APS is working, but the effect has spread out farther because we've increased detail on the other side.

vipvip242
12-25-2013, 03:24 AM
ok you're probably right
thanks again !

Cageman
12-25-2013, 07:21 AM
Yeah. That is how subdivision at rendertime works. The only way to create a sharp transition is to manually subdivide in Modeler (creating a freezed mesh).

seghier
05-14-2015, 03:56 PM
interresting