Re: Performance of records with variant parts

[John Perry <john.perry@usm.edu>]

On Monday, March 22, 2021 at 12:32:39 PM UTC-5, Jeffrey R. Carter wrote:
> On 3/22/21 6:02 PM, John Perry wrote: 
> > 
> > | case obj.kind is 
> > | when Sphere => 
> > | -- do stuff 
> > | when Plane => 
> > | -- do other stuff 
> > | when None => 
> > | null; 
> > | end case; 
> > 
> > Is there a reason that the record with variant parts runs so much slower? I can make the complete source available if need be.
> 1. Why is Surface a discriminant? 

That's a good question. I don't remember why I made it a discriminant. That's easily fixed.

> 2. What are the quantitative timing requirements for the program? Does the 
> difference affect whether or not they are met? 

This is a raytracing program. There are no particular timing requirements, but if I wanted a larger image with more objects things would get ugly. This is really more a matter of my curiosity.

> 3. What is the declaration of Obj?

Obj is an "in" parameter to a function. Do you need more than that?

john perry