I'm having trouble with some shaders. A little guidance would help. First I have a spline object cylinder. I want the object wiht t a consistent shader, but with a bump map on one end but not on the rest. I've tried several approaches, including that discussed below, with no success. A second problem is similar. I have another spline object with a flattened quadrangular cross-section. Again I want the same shader over the entire object, but I'd like a bump map on the top and bottom. I think I've managed this this with two layers, both flat-mapped with the same shader, but with opposite box sides highlighted in the flat mapping channel. The ends were not mapped and showed up with no shaders in the domains list until I dragged the basic master shader (no bumps) used on the flat sides to each end. Is there an easier way to do this? When I tried it on a similar object I was unsuccessful. Thanks.

Can you post a screen shot? There are several solutions to what I think you're describing but it depends on the shape.

Also, what version of Carrara are you using? I just want to suggest something that you can actually do! :)

Message edited on: 03/03/2006 15:41

Thanks, Mark. I have a pile of things to do today, but I'll get some screenshots up as soon as I can. Sorry about forgetting the important version information: 5.05 (latest patch).

Here are a couple of composite screen shots. The first shows the spline object (actually a little more complicated than I stated) that I somehow through trial and error shaded successfully. I've pasted in the second layer mapping and a top view rendered in the assembly room. The original shader is "Blue steel" and the bump map adds a rivit pattern that may not be too visible in these images.

The second composite is of somewhat more complex spline object (altered with an envelope) with what appears to me to be set up identically to the first. The orientation of the second object is 90 degrees different from the first, hence the different faces in the flat mapping component. The top of the object took the rivet map fine but the bottom, shown patched into the screenshot, appears black. Since most of this was done by trial and error I'm not sure how I got to these two points, but I did try to replicate what I did on the first working on the second. I'll post screenshots of the cylinder, which seems like it should be much easier to solve if I have a few minutes later.

This is the shader for the cylinder. I'm looking to have the base shader on the sides and on the top and to have a bump map on the top only. I've tried various combinations of layers but the top face doesn't take a shader unless I apply the top layer to the whole object or I select a shader in the layer list (inset). Nother I do in the second layer, which is applied to that face, has any effect. I've tried a number of mapping projections there to no avail.

Hi Michael,

The shader setup you are using is fighting itself and the "top" shader is winning.

Here is how you fix it: The the different area you want to use for the top needs to be connected to the VERY top level, not the shader already in place.

There is another method I'll show in the next post.

The same fix can be applied to your other Splin objects. Mark

Message edited on: 03/04/2006 17:02

Here is an alternate way to use the shader tools in Carrara. This option is great because you can simple select an alternate shader with a pull-down menu. If the shader in the pull-down menu is ever changed, ALL shader trees using it will also be updated.

This method is also a quicker way to implement complex shading on objects, both vertex and spline, that have multiple shading domains.

Mark

Message edited on: 03/04/2006 17:07

Thanks, Mark. You've been a tremendous help. I figured I was missing something simple. I'll pay more attention to the shader hierarchy now. The hierarchy is easier to see if you collapse the layers with the little black triangles. As you point out in your second note, there are several ways to achieve results, bu they also conflict. After I adjusted the cylinder hierarchy per your note I still couldn't get the shader to appear on the top face. Then I noticed I'd selected a shader in domains list on the right. When I deleted that the main shader took control. I'm getting more comfortable with this. Thanks again.