hard edges

[ResidnT]

Hello folks, I have a question for you all. Now I've been doing some low poly modeling of a car and I want to keep the outside shell of the car at around 1000 polys or so, which it's all going as planned. But the thing that I am running into is making some hard edges. I've tried to use Edge cusp and the facet sop for this but it will make the points unique. I want the edge to be hard but I also want them to share points. Is this possible. Also there are some wierd shading issues with some black edges, is there any solution to get rid of these as well.

Thanks

Residnt

I have attached an image of the car, sorry for the phong grey but I haven't started to texture it yet. Thats for tomorrow.

[betty]

i was just trying this and found that with consolidate points fast the points were then shared and avoided the unique points issue which was there otherwise. i was actually suprised it did cause unique points. i would have expected the edges to share points to be the default...? mmmm

does this work for you?

what exactly is the 'black edge' problem?

[Szymon]

Do you mean same problem as I had?

http://odforce.net/forum/index.php?s=6497c...st=0entry2713

[ResidnT]

Thanks Betty and Szymon for your replys, but when I use the Edge cusp on just the edges that I wanted I get unique points and the models is actually split up and that isn't what I want. And what I mean by black edges well I guess that wasn't the right word to use I was a little tired. I'm talking about the black shading around the base of the windshield and the whell wells. Hopefully after I get it textured all this will get fixed. Thanks again for the replys.

Jason

[Jason]

Hi there,

The only way to get hard (cusped) edges on geometry is to have the points unique along that edge. I think this works the same way in Maya, but I could be wrong there. Szymon was cusping the entire object instead of just selecting the edges you want to cusp along.

I can only assume that any black edges tou may get is due to bad normals. Turn on your normals in the viewport and check em all carefully.

Hope this helps,

J

ps. There is another way to just render it faceted (using geometry normal Ng instead of the smoothed normal N) but then you can't do it in selected areas easily.

[ResidnT]

thanks Jason, I have checked all of the normals about a hundred times. I think it's just a shading issue right now and the lights aren't set p correctly. I guess what I can do is sort of cheat the hard edges in the texture. Thanks again I will post up another image to get for feedback in a couple of days, since I have to build the interior as well, and it will have textures.

Thanks again

Residnt

[danteA]

Why not just increase the creaseweights on the edges you want to be harder?

Here's something to try:

- Append a default AttribCreate SOP to your polycage geometry. In the Name parameter, put "crease" (without the quote)

- Append a Paint SOP in the viewport. Under FG put 3,3,3 for really sharper edges (assuming that your maximum subdivision level is 3). Turn on the Override Color parameter and put "crease" (without the quotes) in the text field beside it.

- Append a Vertex SOP. Change Keep Crease to Add Crease

- Append a Subdivide SOP, set subdivision level to suit your taste. Set the Template (pink) flag on it.

- Set your Display (blue) flag on the Paint sop that you had created. Hit the enter key in the viewport to start painting your crease weights.

Now the thing to note is that the Subdivide SOP works with vertex attributes but you can only paint point attributes. What this means is that you need to paint both of the points on the edge that you want to be sharper.

dante

[danteA]

I forgot that for fine control, there's also the Crease SOP but that doesn't seem to work properly for me. Probably because I'm not quite sure how it works.

[ResidnT]

Hmmmm, that sounds interesting, but would the crease attrib work with subdivide set to 0, I don't want to subdivide the geometry. But I will have a go at it once I get home tonight.

Thanks again

residnt

[danteA]

Ah, sorry, I should have realized that you were NOT doing a subd surface. In that case, I think you should do an EdgeCusp and then play around with the normals on the uniqued points. Something like the Comb SOP. Since each point can have only 1 normal and you really want 2 normals, then I it's probably easiest to simply have them uniqued.

[ResidnT]

I have another question for you folks. I want to go in now and add the seams for all of the pieces. I didn't realy want to go back in and do it manually, but I will if I have to. I was just wondering if there was a bevel edges or something else that will allow me do something similar. I did find a link that had that sort of thing that I wanted to do but it was a 3dsmax tutorial. Here is the link. http://www.3dluvr.com/grid/tut3D/tut3d.htm Thanks again for all the help.

Residnt

[DaJuice]

Unfortunatley, there is no bevel edge tool in Houdini right now. I think it will be in the next release (it damn well better be, hehe).

'Use constant bias' should work pretty well though.

As for your smoothing issues, try applying subdivide sops with 0 iterations to all the polygons within the same smoothing group (hope I'm making sense).

Not sure if this will work, but worth a try.

--------------------------------------

edit: never mind about the smoothing, should have read the thread more carefully.

[Jason]

I'm not sure if this is what would help, but if you select the edges and then run a Starburst SOP on it you can get some beveling functionality from that.

[ResidnT]

Hey I didn't even think of using the starburst sop. Didn't really know what it did, the name really isn't what it does, sounds like something that will blow up your geometry. Thanks for the tip Jason.

Residnt