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Are UV Sets supported in Maxwell?

Also,

I can't seem to find the textures being used for bump maps neither in the main graph of the shader in the hypergraph nor in the relationship editor (for UV Set linking)

So I got the awkward camera mapping to work in Maya, then added a second planar UV set in Maxwell Studio

(I need to camera project a painting onto a canvas, but I want the canvas grain to be planar mapped flat onto the plane of the canvas)

Multiple UV sets are not supported by the Maya plug-in because Maya and Maxwell use incompatible methods for specifying the UV set linkings. Projected textures are an exception; the plug-in will create additional UV sets for projected textures (only planar and perspective mappings are supported), but you will encounter artifacts unless your mesh is very dense. The correct way of doing projected textures it to compute the projected coordinates at every pixel, but this has to be supported inside the renderer core, and Maxwell doesn't. The plug-in approximates this by computing the projected coordinates at every vertex, but this is a weak approximation if your triangles cover more than a few pixels in the rendered image.

ok, good to know.

As it happens my mesh was dense enough to work.

I was actually referring, however, to the fact that Maya projected UVs place a square bounding box around the projected object instead of leaving it where it belongs. The workaround for that appears to be to make a rectangle exactly fit the viewport, then combine it with the model, then project, then scale all UVs until the viewport rect is square and exactly fits the 0..1 UV square, then separate the models again.

Any plans to support projection mapping more accurately withing Maxwell?

Mihnea Balta wrote:perspective mappings are supported

Can you elaborate on this? Becaue I have to create a bounding box made of a poly rectangle, fit it to the viewport, combine it with the rest of my geometry, scale its UV's (and everything else's) in the UV editor until the poly box fits the UV window, then separate the poly box from the rest of the geometry and hide or delete it.

There is a simpler way to get camera projection mapping with a matched focal length and position to work?

(I understand about the per-pixel vs per-vertex evaluation issue)

When you assign a texture to a Maxwell material, instead of picking a file node from the create dialog, pick a projection node (it's in the Utilities group). Set the type to perspective, assign a file node on the Image attribute and specify a camera to use in the "Camera Projection Attributes" rollup. Before Maya 2011, the create node dialog used to have a radio group with the options "Normal", "As projection" and "As stencil" which spared you the trouble of adding a projection node by hand, but for some reason they removed that.

Very good. Somehow I didn't realize this mapping style was recognized by Maxwell.

Mihnea Balta wrote:Before Maya 2011, the create node dialog used to have a radio group with the options "Normal", "As projection" and "As stencil" which spared you the trouble of adding a projection node by hand, but for some reason they removed that.

This is still available if you right-click

Okay, there is still something basic I'm not getting.

I have 2 objects. Each is modeled and textured and mapped similarly to the other (lets say they are 2 playing cards) using multiple planar maps.

One object renders fine.

The other object gives me this ' UVW channels ( 1 ) on object "polySurface4" not enough for material "plant01Paint" ' stuff and I have no idea why.

I can't see what distinguishes one object from the other.

That sounds like a bug in the plug-in. Could you send me a scene which shows this behavior at mihnea.balta@gmail.com?

So I have a thick card with sides and a back. I have 2 shaders, a simple one for the sides and back and a complex one with several projections for the front.

If I assign the complex shader to the object and then select and assign the side and back faces to the simple shader it's ok.

If I assign the simple shader to the whole object and then select and assign the complex shader to the front face it fails.

Ah ok, I've managed to reproduce it. There's indeed a problem when you assign materials with projected textures per face instead of on the whole object. We'll try to fix it for the next update.

Thanks for reporting this.