|x-ray crab | source: nationalgeographic.com|
- First, notice that x-ray makes the object looks hollow. The intensity of the outer part of the objects is high and gradually decrease when it comes to the inner part.
- Second, the overlap parts have even brighter intensity. This effect is similar to when we use 'Add' in Photoshop layer mode.
- Third, we have some noise when it comes to the inner part.
Open 3ds max, create an empty scene. Now hit M to show our Material Editor window. Grab an empty material slot and switch it to a Standard Material if it isn't.
|Set to Standard Material|
|Use Falloff for Opacity map|
The Falloff map will make our material have 100% intensity on the outer side and gradually decrease to 0% in the inner part. Thus, our shader looks like it's hollow in the inside. We can also adjust the intensity by playing with the black and white color in the parameters.
Now, drag our Opacity map to our Self Illumination map, make an Instance copy. X-ray creates no shadow, so it's a good idea to use the Falloff map also in the Self Illumination map so that our shader will 'glow' and pop out. Don't forget to check on the 2-Sided too.
|Make an Instance Copy of Falloff map to Self Illumination|
Remember the 'additive' part in our brief research? We can do that by checking on Additive in the Extended Parameters rollout. Now we are a little bit closer to our x-ray.
|Use Additive Type|
Click on the M square button to adjust our Falloff map parameter. Since we use our Falloff map in the Opacity slot, then we can play the opacity of our material by adjusting the black and white color. White means 100% opacity, black means 0% opacity, and grey means between them. Adjust the black color to a dark grey so that our material won't be 100% transparent in the inside.
Now you might want to test the material. Create an object, I used Torus Knot, in the scene and hit render. You should get something similar to this image:
|Torus Knot with X-Ray Shader|
So this is our basic shader for x-ray. We can adjust and playing with the maps to create more detailed effect. For example, we can use Noise map in our Falloff map to make some noise in the shader too.
|Use Noise Map to Give Detailed Look|
|Some Parameter Tweaking of the Noise Map|
Well of course you can still play more with the shader to achieve better result. You might need to adjust some of the size parameters in the maps to fit your model. By the way, the more detail your model is, the better you will get the effect.
If you're interested, I want to share my x-ray shader that I used for the T-Rex above. Basically it's the same shader I used from above tutorial, but with a little tweaking and some more maps for the detail. You might learn something from this.
DOWNLOAD: X-Ray Shader
This is a .max file created using 3ds Max 2011 (you can't open this in older max version). Open the file then open the Material Editor and you'll get the shader there.
I hope you find this tutorial helpful and have a nice day. :D