Texture Baking in Maya

First, let me apologize for this post. It seems that there are a lot of these similar questions, but with each thread I looked up it doesn't seem to answer my question.

My issue:

Every time I bake a texture onto my object in Maya I end up with black shaded parts that I can't fix or get rid of. I have enough lights surrounding the object. It renders fine in Maya, it's just actually baking it to a 2D texture where it messes up.

Here's the facts:
1. I am using a custom shader that I installed to get that chrome effect (might be the issue).
2. I am using Maya 2008
3. The object I am using is a NURBS sphere
4. I have 4 lights surrounding the object.


I've already tried my hardest to search for the answer myself. I even tried to figure it out on my own just playing around with the different settings (with no success).
1. I've read all the Maya tutorials, which none seem to go in depth on baking textures.
2. I've purchased a "Maya for beginners" book and an online tutorials membership (which neither goes in depth on how to bake textures.
3. I've tried searching the forums for an answer but it seems like every question has either been misunderstood or hasn't been the solution I need.

Please can someone help me? Did I miss a step somewhere?

I've attached pictures/screenshots of the different things I see.
1. is my render view inside of Maya (this is what I want the texture to look like when applied in world)
2. is the actual 2d texture I baked
3. is applied to same object but in world as a sculpty (front view)
4. is same object with the texture. (rear view)

You seem to have been quite thorough in what you've described, so you probably already checked/tried this - but...

What 'lighting' does the object have in-world? If you are in SL sunlight, one side would be bighter and the other shaded. Or if you have a 'face lamp' or similar on, that will be lighting the side you're standing on (local lighting).

Forgive me if I'm stating the obvious.

Based on where the light and shadow are on your texture, here's what I can deduce about your lighting setup. The two roundish specular highlights in the front suggest you've probably got a pair of point lights in front of the object. The extreme brightness on top of the base, and inside the bowl both face that same direction, suggesting that those two lights are quite intense, casting the majority of light in the scene.

On either side of the object, you've got a smeared specular highlight. This would suggest you've maybe got a pair of spotlights, either in front of or behind the object, whose cones are aimed to just graze the object, not fully envelop it.

There are of course thousands of other possible explanations for what's going on, but this is what seems likely to me. No doubt you'll tell me I guessed wrong about some detail or other. However, whether I was exactly right or not, the fact remains that your light sources are not configured to cast light onto the whole of the object.

Try this. In the perspective viewer pane, click Lighting -> Use All Lights. This will turn off the default light, to show only the effects of light sources you put in the scene. Cam around the object. How does it look? Chances are you'll see that the back of the object is in total shadow, just as is shown in your baking.

Now, crank down the intensity on all the lights, so that they won't wash the object out, and then move them around/aim them so that the whole object is in light instead of shadow. Also, put a large plane underneath the object, to reflect some light up at it. Objects in RL don't just hover in mid-air, with no surroundings (unless you're in outer space). Everything in RL (on Earth) is lit indirectly as well as directly.

Do another bake. It should look much better.

It still probably won't look very realistic, though. The kind of lighting setup you seem to be trying to use is not one you're ever likely to encounter in RL. For starters, you should turn off Emit Specular on all lights except one. In most cases in RL, we're used to seeing shiny objects reflect just one set of specular highlights. It's pretty unusual we'd see specularity go in four different directions at once.

You also must read the tutorial on global illumination in the Maya Help. For general baking, global illumination is arguably more important than any other form of light, especially when the target environment is a place like SL, in which you can't always plan where all the light sources will be. You want your textures to be as neutrally lit as possible, unless you're planning on setting up a full scene, with every object in it being lit exactly the same way.


Keep in mind, this is a big subject. There's a lot to learn, and it takes a lot of practice to get good at it. Some people spend their whole careers just doing lighting.



Oh, and by the way, on a modeling note, you've got an awful lot of wasted vertices on the bottom of the vase. How do I know that? Notice how the left third of your texture is completely black? That's means 1/3 of your vertices, not to mention 1/3 of the pixels on 7our texture, are on the bottom of the object, where no one will ever see them. That's really not a good habit to be in. Those vertices and pixels have to be somewhere; put them to use. By all means, move them up onto the body of the vase. You want the detail where it belongs, where it can be seen. Never waste it where it doesn't. That black area should be just a thin strip along the edge of the canvas.

Also, to avoid the problems with in-world lighting that Valentino describes, surfaces with (well) baked textures should be set to fullbright in SL. Otherwise, the object will never look right. You want the surfaces to be immune to the effects of in-world lights. That's what baking is for.

Chosen Few-
Thank you for all the tips I will check out the global illumination as you mentioned, but that really isn't the issue that concerns me.

Also, the vase was a 2 second thing I threw together to take pictures and give examples of what I've been getting after I baked, so I'm not too worried about the details of the vase.

No matter what light configuration I use area light, spot light, point light. Whether its 2 lights or 20 lights. Whatever configuration or light set up I make it all ends up being the same. The back of ANY object I bake is black regardless of light.

I get a baked texture that bakes half of the light and color to texture and the other half goes black.

OK, I misunderstood where the problem was coming from. It sounds like you've got your bake settings configured to be dependent on your current view. What renderer are you using? If it's Maya Software or Mental Ray, I'm not sure where the option is to turn that off. It doesn't seem to be in any of the obvious places, and I haven't used either of those renderers in years. If you're using Turtle, which is what I use, you'll find the checkbox for View Dependent under Bake Options, on the Texture Bake tab.