[Josephus Holt]

First, I see your very thorough texture mapping explanation you posted back in June...am working through that. With the image (countertop) below I'm using real scale and as you see it does not wrap very well where shown when the object is one polysurface. Wonder if I need to explode some of these surfaces and texture individually, trying then the best way to match them up.[URL=http://img38.imageshack.us/my.php? ... .png[/img]
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[kami]

try using a higher mesh resolution, that will make the problem smaller
It's a problem of the cubic mapping with real scale. Look at that thread: http://maxwellrender.com/forum/viewtopi ... 13&t=30444

[JDHill]

Yes, that's always been a problem with Rhino's box-mapping. What you are seeing is that, as you follow around the curve, there must be a place where the point on the face you are looking at switches from being mapped by one side of the box, to being mapped by the adjacent side. For any face which lies very nearly 45° to both mapping-box faces, there is some issue inside the mapping engine (due to the nature of floating-point arithmetic, I'd guess) about exactly which side of the box should be used, and in this case you will see this type of artifact. It's worked this way ever since the mapping tools were introduced as a texture-mapping plugin for Rhino 3, which was then incorporated into Rhino 4.

[Josephus Holt]

I understand the "problem", will have to figure out the best workaround....maybe not get the camera too close Turning the polysurf into a mesh created other mapping problems...this is not urgent at the moment....just am needing in general to get a better handle on Rhino/MW texture mapping (as I mentioned I'll spend some time with your (JD's) good explanation that you posted).

Do you know if Rhino v5 is addressing this particular texture mapping issue...(I've not had time to look at v5...just trying to learn v4)? I had been told by someone from McNeel when I was considering purchasing Rhino (v4) that they were aware that the Rhino texture mapping needed work and someone was "on" it.

[JDHill]

Probably the best way to deal with it is to do what kami said, increase the mesh resolution. Your mention of converting from NURBS to mesh indicates to me that you may be misunderstanding how to do this; what you would want to do is:

1. select the object
2. go to Object Properties > Object
3. under Render Mesh Settings, check Custom Mesh and click Adjust...
4. use one of Rhino's 2 mesh-parameter UIs (adjust the params, or click Simple Controls and use a slider) to adjust the density of the render mesh

So you will continue to work in NURBS, but you will adjust the render mesh that's created from your surfaces. Please pardon if you already knew this, I don't mean to be obvious, but it's very possible that as a newer Rhino user you might have no idea about this particular corner of the application. Alternatively, you may wish to explode the object, or just to extract some specific surfaces, and map them individually; that decision depends on the particular piece you're working on. In the case of the countertop you showed, I would probably forego box mapping (as noted in the post kami linked, the use of Real Scale implies the use of box mapping) altogether and just use surface mapping.

As far as McNeel 'working on it', I'm sure they are, but as insinuated in the previous post, there was no concept of texture mapping in Rhino at all until V4, so it's still a very young part of the application, and it's not the easiest thing to deal with either, due to Rhino's NURBS nature; mesh modelers have a much easier time of this since there is no need for a separate 'render mesh'.

[Josephus Holt]

thx JD. You correctly surmised that I was not familiar with that....I really need to go through Rhino from a to z.

Running into another "problem" while doing this. The Rhino rendered preview does not match the Maxwell render mapping. I looked for a way to show the Maxwell rendered mapping in Rhino but could not find it.

[JDHill]

I'd need to know how things are set up to know what you're seeing there. Which channel(s) are your textures using in your Maxwell material? Which type of mapping is assigned in Rhino for this channel? If you open the plugin's material editor and click between the different textures (empty ones to 'un-show' the texture) does the plugin enforce the correct mapping in the viewport?

[Josephus Holt]

ok, I see the error of my ways...sorry you have to deal with such a moron...I had been looking at the reflectance layer mapping and not the base color mapping
This is an mxm from the materials site and each is set up a little different...have to be more careful

[JDHill]

Sorry if I came off as being curt, I didn't mean to. I don't think there are any silly questions, so just ask away whenever you run into something that's confusing you.

[Josephus Holt]

I did not get the feeling WHATSOEVER that you are being curt or anything of the sort...I just feel badly being as they say, a bit "high maintenance". I could not ask for better help...you've been the greatest.

My next work will be finishing up and rendering this model....something easy

[koolhaas]

JDHill,

I am fairly familiar with Rhino but somewhat new to the rendering side. Should I adjust the mesh settings for the whole scene using the Document Properties>Mesh settings and then adjust the mesh for individual objects as necessary? Is this how you work with modeling in NURBs and rendering in meshes? I am just trying to get a gauge as to how an experienced Maxwellite uses these settings. Thanks for any comments

[JDHill]

Yes that's about the size of it. I adjust the mesh settings for the document to produce meshes no denser than necessary for the general distance of the camera, then adjust individual objects only if/when necessary. Heavier meshes do not necessarily take any longer to render in Maxwell, but they do take longer when exporting the meshes from Rhino into the MXS file and they consume more memory, both during export and while rendering.