www.quadsoftware.com
FAQ  FAQ   Search  Search   Memberlist  Memberlist   Usergroups  Usergroups
Register  ::  Log in Log in to check your private messages


Post new topic  Reply to topic
 Can we please have a Quad option in the mesh exporter? « View previous topic :: View next topic » 
Author Message
RS Digital Studio
PostPosted: Sat Sep 11, 2010 4:38 am    Post subject: Can we please have a Quad option in the mesh exporter? Reply with quote



Joined: 18 Aug 2008
Posts: 13

Dear Sir/Madam,

I would like to know if a quad option can be created in the mesh exporter when exporting terrain zones out of Grome?

Thanks.
Back to top
View user's profile Send private message
ALicu
PostPosted: Mon Sep 13, 2010 6:36 am    Post subject: Reply with quote



Joined: 12 Feb 2007
Posts: 1326

Hi,

When you referring to "Quad option" do you mean "4 vertices polygons" ? If so, to be noted that most of the current video cards don't know how to render quads (they simulate them with 2 triangles). Also heightmaps or regular meshes cannot be represented by quads unless the geometry is significantly modified.

At what exporter are you referring? Collada exporter?
Plus, are you referring to heightmap export or simplified mesh export?

One solution would be to apply a separate external tool on top of exported geometry to transform it to quads. But, again, I don't know if this kind of tool exists since nobody really wants quads. Triangles are the most common way, followed by triangle fans.

Can you please indicate why do you need quads?

Best Regards,
Adrian L.
Back to top
View user's profile Send private message
RS Digital Studio
PostPosted: Mon Sep 13, 2010 7:44 am    Post subject: Reply with quote



Joined: 18 Aug 2008
Posts: 13

Hi Adrian,

I can only assume that when you refer to video cards being unable to render quads that you are referring to the fact that most Next-Gen Game Engines can only read triangulated meshes during real time rendering...however... there are several engines that automatically convert quad mesh into tris when the assets are saved for that engine specific model format. Not quite sure what you're trying to say with the quad based thing because anyone that works in the 3D industry knows that quads are preferred during the modelling and sculpting process. In the industry it is common practice to leave everything as quads until the last minute. The reason for this is it allows cleaner topology and in our case the reason we want it in Grome is because we want to take certain zones of the terrain into ZBrush to do extra sculpting work. Some examples for wanting to do this are as follows: sometimes we use Grome to generate models of cliffs so we need to be able to take that mesh into ZBrush as a quad base mesh and subdivide it to several million polygons to allow for much higher resolution sculpting and then re-topologise the cliff and bake the normals from high res to lower res. Second reason you might want to do it is sometimes if you have a high resolution terrain in Grome and you want to generate normal maps of that for use of LODing lower versions of that terrain, it's always handy to be able to put the mesh through Decimation master in ZBrush. That will only work with quad based meshes.

If this can't be added to allow exporting out as quads that's fine, I'll just keep doing what I've been doing which is to export the heighmaps out of Grome and load them into GeoControl which does allow me to save out quad based mesh.

Thanks.
Back to top
View user's profile Send private message
ALicu
PostPosted: Mon Sep 13, 2010 8:25 am    Post subject: Reply with quote



Joined: 12 Feb 2007
Posts: 1326

Hi,

I see. The problem is that you should have Grome enforcing quad topology at any time during editing (which is not implemented and I don't think it will be soon since most of clients want triangles anyway) which is not that easy. That's because we apply generation algorithm on heightmap points which can be at any height relative to their neighbors. For example, in a terrain tile, you can have 2 diagonal vertices which are at 100 meters and the other two (from the neighbor corners) at 110 meters. This configuration cannot be represented by a quad, you need two triangles splitting the tile.

As a side note, triangle based tessellation of heightmaps is also useful when you can control the way the diagonal split is done (the "turn edge" option you can find in engines like Unreal). We want to introduce this in the future to allow fine representation of ridges, terraces and other sudden-height-changes features. Currently if you happen to have your ridge with the wrong diagonal orientation you get staggered edges. The effect would be amplified by an all-quad representation.

Normalmaps will be able to be created and exported directly from Grome (in the next version) so this may help you. In the mean time you can use your current pipeline. You may be able to find a command line utility that converts from triangles to quads and apply it automatically during export from Grome (you have the source of the exporters so you can easily change them to call an external utility).

Let me know if I can provide more information which can help on this matter.

Best Regards,
Adrian L.
Back to top
View user's profile Send private message
GrimMoroe
PostPosted: Fri Sep 24, 2010 10:00 pm    Post subject: Reply with quote



Joined: 13 Jun 2008
Posts: 7

Hey RS,

This is not a direct solution but it works really well for what your talking about. I use grome in the same way you are describing.

The way I do it is I export the mesh and convert it to an obj file then open in a program called topogun lay out a single quad and subdivide. The new mesh will conform perfectly to the highres mesh and retain quads which can then be sculpted in zbrush.

Topogun can be used for all your meshes and is a must have tool in your box.

http://www.topogun.com/

I hope this helps as I feel your pain.
GrimMoroe
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic  Reply to topic Page 1 of 1

Jump to:  



You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Based on a template by Dustin Baccetti
Powered by phpBB © 2001, 2005 phpBB Group