ACTUALLY, it's a [350][34][6] problem.

350 time frames, 34 actors,  3 velocity coordinates, 3 position coordinates.

Already burned out mentally from work and not sure I want to try this one
tonight...

John VanSickle wrote:

> Greg M. Johnson wrote:
> >
> > John VanSickle wrote:
> >
> > > Greg M. Johnson wrote:
> > > >
> > > > I wish that the documentation better explained the syntax for
> > > > #read and #write.
> > > >
> > > > I have created a file of the positions and velocities of a number
> > > > of particles, (34 particles at 350 time periods).  I have pasted
> > > > the first four records from my file.
> > >
> > > Generally, when I have an outside program generate data for POV-Ray,
> > > I have the same program output a standard .INC file, with all of the
> > > #declares, #locals, etc., needed for POV-Ray to parse the file
> > > directly. This requires very little extra effort in the program that
> > > generates the data, and the results parse a lot faster.
> > >
> > > For instance, in my last IRTC entry, the insect parts were made of
> > > bicubic patches, which I converted to meshes using a bit of macro
> > > code.  I got tired of waiting for the macro to parse, so I modified
> > > the macro to write the triangles to a file, in full POV syntax.
> > > From then on I merely #included the generated files, in place of the
> > > original generating code.  Things parsed much more quickly.
>
> > So, like how would you make your inc if you had two variables which
> > were [350][34] each?
> >
> > Would your file generator literally say:
> >
> > #declare position.x[1][1]=1;
> > #declare position.y[1][1]=2;
> > #declare position.z[1][1]=3;
> > #declare position.x[1][2]=4;
> > #declare position.y[1][2]=5;
> > #declare position.z[1][2]=6;
>
> No, the file generator can also dump out the following:
>
> #declare position=array[350][34] = {
>   { <1,2,3>,<4,5,6>, ... }, {... }, ...
> }
>
> The PovRay code would look like this:
>
> // START OF SAMPLE BASIC CODE
>
> #write(MyFile,"#declare position=array[", ROWS, "][", COLUMNS, "] = {\n")
> #local iI=0; #while(iI<ROWS)
>   #if (iI>0) #write(MyFile,",") #end
>   #write(MyFile,"{ ")
>   #local iJ=0; #while(iJ<COLUMNS)
>     #if (iJ>0) #write(MyFile,",") #end
>     #write(MyFile,MyDataArray[iI][iJ])
>   #local iJ=iJ+1; #end
>   #write(MyFile, " }\n" )
> #local iI=iI+1; #end
> #write(MyFile, "}\n" )
>
> // END OF SAMPLE CODE
>
> Your file generating program can print out the #declares, square
> brackets, angle brackets, squiggly brackets, commas, and so forth.
>
> The only difficulty is that if you want to have text data in there as
> well, you have to explicitly print out the quotes with the CHR$()
> function:
>
>   #write(MyFile, "#declare MyString="; CHR$(34); "Stormbringer";
>     CHR$(34); "\n")
>
> which will create a line of text that looks like this:
>
>   #declare MyString="Stormbringer"
>
> You can feed a vector to the #write() directive as well; my example does.
>
>   #write(MyFile,x-y+z*3)
>
> will cause the string
>
>   < 1,-1, 3>
>
> to be written to MyFile.  There is no need to bust up the vectors into
> scalars, only to build them back up later.
>
> Of course, keeping track of the brackets and quotation marks can be
> a bit of a trick. :-)
>
> > I know how to write such a file, but wouldn't this make it a huge INC?
>
> As you can see from my response, it will not be very much larger than
> the file you already plan to use.  It might be twice as big, but that's
> what we have hard drives for.
>
> > Are you sure this is faster than reading with a #while loop the
> > following data:
> >
> >  1,2,3,4,5,6,
>
> Yes, it is much faster.  The file is generated in a form the parser
> already knows how to understand; the other method you discuss goes
> through a #while-#end loop, which takes extra time in any interpreted
> language.
>
> Hope this helps,
> John

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