need Car Paint help

[rohand]

hi,
there is a tutorial for carpaint on 3dtotal but its for max using brazil. however the technique is pretty simple and can be used in XSI.

just take a mix 2 colors node for the diffuse color and one for reflection. keep the diffuse colors to a lite and dark shade of the color u want the car to be and keep the reflection colors to a lite and dark shade of gray. Then connect an incidence node to both of their weight colors. The diffuse should have the lighter color on the inside and the darker on the outside and same for reflection. this will make the reflections fade away towards the edges.

Then put a huge plane or a really flat box on top of the car. Give it a constant shader with a white color. This will a give the car something to reflect and also act as a specular. That reminds me dont give the car shader any specular at all. If u want the reflection to be stronger just boost up the vale of the constant shader diffuse color. the basic value for white in xsi is 1.0,1.0,1.0 just increase it to 2.0 or more.

Set the environment to a shade of grey. Render it using final gathering. Keep your light source really dim as the plane on top will contribute to the lighting as well as the environment, once u switch on final gathering.

This should give u what u need . I would still say u should check out the tutorial on 3dtotal.

If I am not mistaken there is a shader available at xsibase called D3shader it had an inbuilt option for carpaint. It's worth checking out.

I hope this helps.

[tachy0n]

You can also try using an HDRI file for the reflection environment, which can give the paint something nice and complex to reflect...

[TheShaddix]

Have you ever tried this technique of yours yourself ? There is a lot more to it than just white planes and final gathering. In fact, sometimes u don't even need final gathering. If you look at real cars, you can see that when it's a sunny day, cars will have a strong, sharp shadow underneath, thus making Final Gathering useless in that case. Also, when it's sunny outside, you can see that every car has lots of specular on them. If your goal is an ok paint with unrealistic reflections, then this approach is for you. Using the incidence adds some realism, yes. Some paints have the opposite of what you said: more reflectivity when the surface is angled instead of when it's turned 90 deg. to the camera. What people forget is that in real life there is no 100% clean reflections. Some have noise (metallic) added to the paint; some have rough reflections; some don't even have any reflectivity at all. My point is that, if your goal is realism, then you have to deal with compositing your car into a real environment, matching up the paint until you get what you want. The hardest thing is to take all this info and turn it into practice. Using white planes for reflections is not cutting it anymore. Maybe it was cool sometimes, but i know for sure that there is no way you can see such thing in real life (outdoors). Good luck with it though.

[rohand]

TheShaddix I have tried it myself in max and XSI. I know it's not the most perfect solution for a car paint material but it is a good start. You can always make variations afterwards once you have the basic look and feel.

Also your reflections depend upon your environment, so yes an HDR image will definately be much more effective than a simple white plane.

I had just suggested a beginning.

[AzNightmare]

will this give me that "sparkly" effect on the car?
like for example if i made my car silver, it has those dots or specs or whatever you call them. well hope you guys know what i'm talking about.

i have used HDRI maps before. i get nice reflections but still doesnt look like its metal from a car.

thanks for the help guys :D

im gonna go try what you told me to do in the previous posts.

[TheShaddix]

OK, as i said before: for metallic paints, just use that "flagstone" map in XSI. Plug it into ur color slot. Set the UVRemap settings to about 150, do tweaks here and there, and then render it. Oh, make sure that for the two colors you choose grey and darker grey (drag the first one over to the next one to copy). Play with it. If the noise appears too big, increase the values. Oh, the most important part: for ur antialias settings in the render window, set it to 1:3 at least, choose "mitchell" as ur filter type. Your render will be more sharp and clean.
Here is the result of my obsevations: http://www.alliedplayaz.com/alliedplayaz/images/misc/wheel2.jpg

If that's the kind of paint u're talking about.

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