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Richard Hebert
08-30-2009, 10:11 PM
I probably can already guess the answer but I'm going to ask anyway because I still have protection under the NewTek Newbie Clause... can procedural textures affect caustics or does the geometry have to be actually distorted to produce caustic effects? Thanks for being incredibly patient.

Richard

jameswillmott
08-30-2009, 10:23 PM
If the surface normal is perturbed, caustics will be affected. This means either displacement, bump mapping, or normal mapping will (should) affect them.

Richard Hebert
08-30-2009, 10:33 PM
Well, that's better news than I expected. I'm using a procedural bump map on a poly to produce water but I'm not seeing any caustics with the caustics box checked. Could be any number of things that I'm doing wrong (more often the case). I've discovered that spherical lights do not allow for caustics so I switched to a point light source for the scene. If I wanted the procedural texture to reflect a caustic effect onto the hull of a boat is that even possible?

Richard

jameswillmott
08-30-2009, 11:20 PM
It's possible, but you're probably much better off cheating.

On the hull of your boat I'd use a luminous animated ripple texture, with falloff so it's only applied near the water. It won't flicker during animation, it's fast, and you have so much more control over it than calculated caustics.

SplineGod
08-31-2009, 03:47 AM
Or apply a blank black image to a spotlight so that its projected thru it.
In the image editor apply the textured filter plugin to the blank image. Use this
to apply a procedural texture to the blank image as a preprocess effect. The
procedural can be animated. This will be projected thru the spotlight, cast shadows,
volume etc.

Richard Hebert
08-31-2009, 08:08 AM
Thanks for the tips. I'm going to give both of those a shot. I'm still learning about what can be done realistically and what has to be done through more creative means. I have a procedural texture applied to the water surface and it has attributes that can be animated but those attributes affect the size and intensity of the texture and not necessarily the randomness of the texture. The water has a Ridged Multi-Fractal procedural bump on it but it doesn't appear to have the ability to 'randomize'. Any ideas on how to get the water to 'move' with that proc. texture? That one gave me better results than some of the others.

Richard

SplineGod
08-31-2009, 04:20 PM
Animate its position in the texture editor using an envelope.

Richard Hebert
08-31-2009, 05:22 PM
Thanks Splinegod, would have never thought of that. Today, you're king.

Richard

SplineGod
08-31-2009, 05:43 PM
No problem :)
Deis Pontonier has a bunch of procedurals in his Rman collection.
One is called windy wave and tis great for doing water and its free. :)

Richard Hebert
08-31-2009, 08:20 PM
Thanks bunches! Just downloaded them and cranking up the test renders! I sure wish I had the aptitude to be able to write code myself. I feel like a major free loader sometimes and have actually very little in terms of expertise to give back to the community. If any of my rendered animations could help to inspire another new LightWave user, well... that would be a good start.

Richard

toby
09-02-2009, 11:43 AM
Just turning on caustics won't get you much of anything, it's default settings are from the pre-ghz days. I usually end up with at least 3000 samples. And unless you've calibrated your sun's intensity to be accurate, you'll have to crank up the caustic's intensity to see it. Lastly, the water surface will need to have reflection, not just specular.

Richard Hebert
09-02-2009, 02:36 PM
Thanks for the adjustment info. The water has reflections applied, just not set very high.

Richard