View Full Version : Static noise modifier animating in PFlow...

07 July 2011, 02:53 AM
I created an asteroid using noise modifiers in Max2011. The noise is static (not animated). No phase or seed keyframes. If I render a sequence everything is fine, but here is my problem:

I want to create an asteroid field in PFlow. I used a shape instance of the asteroid, set up everything, movement is good, etc., but when I render out the PFlow animation ALL of the asteroids have animated noise! I don't get it it, only the PFlow asteroids! Where are they getting the animated noise from?

What am I missing here?

Thanks in advance,


07 July 2011, 04:23 AM
This sounds spooky since the Shape Instance does not grab animation from the mesh by default even if the Noise modifiers were animated - one would have to check the "Animated Shape" option in the operator to actually make the asteroids show the animation...

Some questions:
*Can you post a short video of what the "animation" looks like?
*Can you post a screenshot of your PFlow editor?
*Do you have just one asteroid mesh or multiple?
*Does it still happen if you collapse the source model to Editable Mesh (killing the modifiers)?

07 July 2011, 02:10 PM
Thanks for the quick reply Bobo.

I already tried collapsing the stack yesterday, didn't work. I put a mesh select on top, then converted to an editable mesh, but didn't change anything.

Then I thought maybe it was the shadow map or the scanline renderer, so I switched to Mental Ray using ray-traced shadows instead, but it still looks the same.

Last, I'm using a cellular material in the bump slot. So I checked the curve editor and the material for any animation keys, but nothing. I can rule the material out anyway because when I render the asteroid by itself there is no movement in the material. Only PFlow asteroids have the problem. This is so strange!

Here is the screen grap of my PFlow and a quick video. The second half of the video is a sequence render of the asteroid without pflow.



07 July 2011, 02:55 PM
I see, that explains it.

The Procedural Maps default to Object Space mapping. The map takes the XYZ bounding box of the geometry object and maps according to that. It works great with a single geometry object, and in the viewports, since Max cannot preview 3D procedurals, it uses a 2D proxy in UVW space, so it looks good. But when you use the Material of the source mesh on the PFlow, the PFlow's Object Space is actually coincident with World Space, and the asteroid particles are MOVING THROUGH that space, thus swimming through the texture. What you see in your video is meshes moving through the texture, producing an effect that looks like animation, but it is just the 3D procedural texture being "revealed" by the passing geometry.

The typical way to fix this is to copy the Object Space mapping into a UVW channel and use explicit 3D UVW coordinates for the procedural map. You add an UVW_Mapping modifier to the original asteroid mesh, switch it to "XYZ to UVW" mode and set it to a UVW channel you want to use for your Cellular map. Then you switch the Cellular map from "Object XYZ" to "Explicit Map Channel" and dial in the same channel as in the modifier (default is 1 in both). Now your cellular map will use the UVWs of EACH asteroid particle within the PFlow and will stick to the particles instead of the particles moving through the texture...

Hope this helps.

07 July 2011, 04:11 PM
Thank you so much Bobo, it worked!

I actually set the UV Mapping modifier to channel 2 along with the cellular map so I could keep my diffuse and specular maps on channel 1. I forgot to mention I had texture maps in those slots.

I never would have figured that out, but now I understand what happened. Thank you for the explanation as well as it gave me a better understanding for future reference!

Awesome! Now that it's fixed I can work on collisions and multiple shape instances to take this further!


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