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Author Topic: Flickering in frame from map  (Read 675 times)

CQ2828

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Flickering in frame from map
« on: July 11, 2022, 12:28:20 PM »
Hi,

I am using the frame from map from the forest pack to represent grass swaying in the wind.
The map uses a gradient ramp, but flicker occurs where the map switches between black and white. Is there a way to solve this problem?
Please see the attached file.

The geometry is a looping animation from 0-100.
The gradient ramp also cycles from 0-100.
I am using 3dsmax 2022 and Forest Pro 7.3.1

Paul Roberts

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Re: Flickering in frame from map
« Reply #1 on: July 11, 2022, 12:32:51 PM »
Looks like something to do with the interpolation of the gradient. Would you mind uploading that sample scene so I can take a closer look.

Thanks,
Paul
Paul Roberts
iToo Software

CQ2828

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Re: Flickering in frame from map
« Reply #2 on: July 11, 2022, 12:56:29 PM »
Hi,
I have attached the scene file.
Please check it out.

Paul Roberts

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Re: Flickering in frame from map
« Reply #3 on: July 11, 2022, 02:35:34 PM »
Thanks for the scene. I think in this case it's a simple case of maths. The frame from map feature controls the playback using the greyscale value of the map. This means you could potentially have 255 full frames. In,  this case there are 99 frames being sampled which doesn't divide well into 255 (theoretically a new animation sample every [2.5757,2.5757,2.5757]  RGB). So I think it sometimes skips or adds samples here and there due to rounding and causes a small stuttering effect.

Changing the animation and the number of samples to 128 might help to smooth it out.

Best,
Paul
Paul Roberts
iToo Software

CQ2828

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Re: Flickering in frame from map
« Reply #4 on: July 11, 2022, 04:04:20 PM »
I have received the attached file. Thanks for your support, it is much appreciated.

But I'm sorry, but this may not be the problem I am thinking of. Can you confirm the flicker that occurs when the black and white border passes?
I have attached file.
I am experiencing this problem here in the scene file I received.

thanks.

Paul Roberts

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Re: Flickering in frame from map
« Reply #5 on: July 11, 2022, 04:11:58 PM »
Ah - we are talking about different things. I thought it was the slight irregularity in spacing between the samples. This one is a much easier fix, it's caused by the Blur value that Max applies to all maps by default. Set this value as low as you can and it should get rid of the issue.



Paul
« Last Edit: July 11, 2022, 04:15:24 PM by Paul Roberts »
Paul Roberts
iToo Software

CQ2828

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Re: Flickering in frame from map
« Reply #6 on: July 12, 2022, 08:32:26 AM »
Sure, the sample was irregular. Thank you for the fix.
I was able to solve the problem by setting the blur value to the minimum value.
And I was able to fix the problem by setting the blur offset to minus.

Thanks for your support.
« Last Edit: July 12, 2022, 08:37:43 AM by CQ2828 »

Paul Roberts

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Re: Flickering in frame from map
« Reply #7 on: July 12, 2022, 10:18:30 AM »
Happy to help out. Thanks for sharing the video of the working version. It's quite hypnotic.

Paul
Paul Roberts
iToo Software