Re: [long, probably pointless] Take me out to the ballgame...

[Matt Birkholz]

On Mon, 2020-02-17 at 22:24 +0000, Scheming Pony wrote:
> This whole thing started when some punk said MIT/Scheme had no applications.

That might have been me :-) and still is, videos of virtual baseballs
in flight notwithstanding. :-}

> I <3 Edwin, man.

Oops.  I didn't know anyone was using that.

> ;;; Code to animate a projectile, simulating a baseball in flight, for MIT 
> Scheme 9.4
> ;;;
> ;;; Uses the Vizajo interface (via FFI) to Pikturo (Open Inventor compatible 
> library).

Oops.  I didn't know anyone was using that either.

Callbacks any?  The old microcode modules did not have them, so I
expect they remain largely unexplored, outside of my Gtk interfacing.

But now you make me wonder.

> ;; TODO: there must be a simpler way to find a
> ;; TODO: file to load in the system library directory
> (with-working-directory-pathname
>  (->namestring (system-library-directory-pathname))
>  (lambda ()
>    (load "vizajo-mit.scm")))

Unless "vizajo-mit.scm" needs working-directory to be system-library-
directory, this might be "simpler":

  (load (system-library-pathname "vizajo-mit.scm"))

> ;; format does not have the ability to put in leading zeros
> ;; for a fixed length integer, so we have this function to do it
> (define (build-image-path prefix frame ext)
>   (string-append prefix
>                  "-"
>                  (cond ((<= frame 9) "00")
>                        ((<= frame 99) "0")
>                        (else ""))
>                  (write-to-string frame)
>                  ext))

Who needs format who also has... ummm... string?

(string prefix"-"(%02d frame)""ext)

(define (%02d n)
  (string-pad-left (number->string n 10) 2 #\0))

>      (flo:defer-exception-traps!)> 
>      ;; glX can cause floating point underflow exceptions, defer them

Cairo too!

> ---- from the other mailing list ----

> Nobody watching me, no compromises, just a pure creation engine. I
> want to get back to that. I couldn't believe the ensuing platform
> wars. I'm tired of fighting other people's crap wars, and even
> thinking about it. I'll sit here at #106 Scheming Pony Way and write
> the damn thing myself if I have to. Nobody even seems to be listening
> to me anyway.

That's the Birchwood Abbey fight song!

I don't know about listening, but I hear you, Mr. Stewart (IF that is
your real name).

-Puck