Good Evening,

It seems that whenever I try to make a blend material with a distance blend falloff, the mix does not work when I render multiple frames. When I render a single frame, the blend works, but if I render a series of images, the blend remains where it was at the start frame.

For instance, I have a ball, with a blend material on it, and a falloff distance blend for the mix map, with the camera moving closer over 10 seconds. At 10 meters away from the camera, it is blue, then turns to red by 2 meters away. If I render a single image anywhere on the timeline, it is at the proper point in the blend, e.g. at 5 seconds it is a purple color, since it is fading between the two colors. But, if I do a render from frame 0 to frame 300, the ball just stays the color it was at frame 0.

I don’t suppose anyone has come across this, or knows a way to force 3DS Max to recalculate the blend on each frame, or any other possible solutions? I have attached images below to further illustrate my point. I am using 3ds Max Design 2012.

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It’s a mental ray bug. When rendering single frames it seems to work, but rendering an animation it does not.
I’m not aware of a fix for this other than not using mental ray. If that’s not an option you will have to invent a workaround to get the same effect.

Ah, that’s unfortunate. If I find a work around I’ll post it. Thank you for your feedback.

I seem to have found some semblance of a work around, at least for some intents and purposes. I needed the distance blend for the camera to switch between an aerial view and a close-up view of terrain when the camera got close enough. While distance blend doesn’t seem to work with mental ray, removing the mask entirely then binding the mix amount to the camera’s World Z position with a reaction controller in the graph editor worked quite well, when the camera is flying above the site, it holds the aerial footage, but when I dip below say, 10 meters, it blends to the close-up material.

I have falled foul of this one before when trying to use a multi resolution grass shader, with displacement and a close map for the close up, but an aerial view map for in the distance, and an intermediate map inbetween.
A good idea in theory, but it did not work so well.