[PLUG] looking for a 3d surface plotting program (besides gnuplot)

[American Citizen]

Hello:

I am working with the NASPMON project (see 
https://www.ig.cas.cz/en/naspmon-project-website/) on an original 
research project pertaining to seismic detection of underground magma 
movement prior to a fissure eruption (which Iceland has).

I have processed the seismic data, using fftw to run the discrete 
fourier transforms on the data, in order to find the frequency 
correlations. Where I am running into a problem is using splot to do the 
3d surface map.

The data is huge, typically 3600 by 4000 data elements on just one plot 
(of 425) of an hour's worth of data.

Has anyone used 3d surface plotting software (other than gnuplot splot 
with pm3d) ??

Thanks for letting me know. I have to create the png files, then 
assemble them into a video too.

Randall