Displacement fun (or not so...)

[ravexl]

I'm displacing the panel design onto a poly object with a hole in it ( the opening for the trash). The problem I'm having is getting just this panel to displace. I'm currently using 3D displace with a multi-sub object, but as you can see if you look through the trash at the opposite panel, the edges of the displaced face are higher than the others (along the lip) and it has a little wave to it.

I've tried 2D displacement with an alpha tiff and a plane UVW, but then I lose the opening's lip edges (perpendicular to the displaced face).

It seems I've tried every idea I had using 2d and 3d, what's the proper way to get this to work correctly? Thanks!

[ravexl]

Here's with a scaled UVW, how would I get rid of "seam" or the edge of the displacement?

[RErender]

using the "shift" offset should do it.

[flipside]

Make sure your map is black with white lines that should displace. if you want the lines to go in, use negative values. (in vray dsiplacement, black color means zero)

The shift value should also be a good solution though

[ravexl]

Well, the shift didn't seem to do it. Here's with a value of -.2 then followed with a value of +.4




I will try reversing my map (it was white with black, I'll invert it in max and play some more).

I assume you're suggesting that using a scaled UV map (like a decal) is the better solution, versus using a UV map that covers the entire object?

Thanks much!

[ravexl]

Well, here's black background, white lines with negative displacement...

I'm going to setup a smaller test file and retry the suggestions. Should this really be this difficult? Surely the displacement can be contained some how...

Thanks!

[J_Bug]

Try applying an UnwrapUVW modifier then scale all of the UV verts so that they are kinda clumped together in a section of the bitmap which matches the level of displacement that you want there. If you need the same UV coordinates for another map that will act as a diffuse or something other than the displacement then you should copy the mapping to another channel with some free script or something before you modify this channel.

--Jon

[flipside]

This should really be very simple actually. It seems you're using the water level option because it clips away geometry! I'll do a quick test later this evening. If you want your bitmap to act as a 'displacement decal', set the tight bounds option in the displ options, and uncheck tiling in the map parameters.

[flipside]

Mmmm it seems A LOT is wrong with the displacement these days...

I get the same weird stuff as you're having, altough I'm 100% sure I used it succesfully before.
When I use 2d displacement, I get good result with black map and white lines, and then amount set to negative value. But with 2d displacement, I can't stop the map from tiling. The tight bounds option has no effect anymore, I'm sure it worked before! Also with 2d displ, the object always explodes at the sides, even with the meshsmooth modifier trick applied.

A while ago, I prevented the edges from exploding in 2d displacement, by just selecting 3d displacement and activate the keep continuity option, and then going back to 2d displacement. Very funny but it did work! Don't know but I can't get it to work anymore.

When I use 3d displacement, I can't get it to work with negative values, I get this clipping effect too. This is completely wrong.

I do get the desired result with 3d mapping if I use a white map with black lines. Then set amount to 1, and set shift to -1. Also deselect the tiling in the map options and it wil not tile in displacement.

Another thing that bugs me is when you use 3d displacement, that the mesh density of the object has such an effect on displacement quality. I thought that this was the strength of MTD, that it was not dependant of the mesh quality. With 2d displacement, this is the case, you can put it on a single polygon and it still looks good.

[ravexl]

flipside - Glad to hear I'm not just going crazy, haha. I've had same issues in 2D with tiling occuring and the such, even with the options properly set.

I will play more with 3D displacement and mesh density, see if I can get a clean and acceptable solution. You UVW map'd with box type?

[ravexl]

Well, it works, but doesn't fix my initial problem.

Below, Green is submat 1 and Blue is submat 2 of a multiobject material. I scaled the UVW to be just in the lower portion of the object, but you can still see that the entire green side is larger than the blue side (by looking at the top trim).

This was done with 3D mapping Amt: 3, Shift: -3, Prec: 15, Subdivs 80, continuity thresh .01. The object is an extruded spline (set of rectangles) with no cross sections.

[flipside]

Mmm i never had that problem actually. Now I see that this was your initial problem

I used planar mapping for UVW

Did you try it on a simple box too? Maybe it's the way you modeled it?

[ravexl]

Well, even with a regular old box converted to poly I get the same thing. The settings are pretty much as described above, changed the face subdivs to 80. Results pretty much equal with planar or box UVW.

The black lines are the poly edges... I have no idea why they are coming out. Also, you can clearly see the size difference.

You sure this doesn't happen with your tests? Anybody else go through this agony?

Thanks much!

[flipside]

I don't have that problem!

Make sure you don't put your map in the materials displacement slot also, you get very weird results if you do that!

[RErender]

I should of thought of this before, it is ok to use the displacement slot in the material but you have to disable Max displacement in the render dialogue when you do it that way or else you will get double displacement