POV-Ray : Newsgroups : povray.beta-test : [doc] language basics in quick ref : Re: [doc] language basics in quick ref Server Time
29 Jul 2024 20:13:34 EDT (-0400)
  Re: [doc] language basics in quick ref  
From: Robert Chaffe
Date: 12 Mar 2002 21:14:23
Message: <3c8eb5ff@news.povray.org>
NOTE:  My changes are to the Quick Reference found at my web site,
http://www.donovansweb.com/~chaffe/quickref.html .
I believe someone with the moniker "ingo" is in charge of modifying the
distributed documentation.  ;-)


news:mspr8uggk6rr2ifipn9r6o8dfgkp7emqi6@4ax.com...
> POV 3.5 b 12 for Win
>
> 10.1.3.1  Floats
>
>   says that NUMERIC_EXPRESSION can be VECTOR.DOT_ITEM
>   where DOT_ITEM is x|y|z|t|u|v|red|green|blue|filter|transmit|gray|hf
>   while #warning str(<1,2,3,4,5>.hf,0,-1) works for all dot items except
hf
>   (I suppose .hf is valid only inside user defined functions)

I have added one of my peach colored notes below the DOT_ITEM syntax:
    The  hf  item may be used only in a user-defined function.

> 10.1.3.4  User defined Functions
>
>   min(FLOAT, FLOAT), max( FLOAT, FLOAT )
>   should be probably something like
>   min(FLOAT, FLOAT ...), max( FLOAT, FLOAT ...)

Tsk, tsk.  Copy-Paste error.  In the FN_FLOAT_FUNCTION list I now have:
    max (FN_FLOAT,FN_FLOAT[,FN_FLOAT]...) | min
(FN_FLOAT,FN_FLOAT[,FN_FLOAT]...)

Note that I use FN_FLOAT to distinguish it from the other FLOAT that is not
quite the same as the one for user-defined functions.

> 10.1.3.4  User defined Functions
>
>   going follow syntax identifiers I can't find how to prepare function
>   with object pattern

Didn't know we could use it.  See modifications below.

> 10.1.3.4  User defined Functions
>
>   going follow syntax idnetifiers I can't find combination to allow
>   function { pattern { brick turbulence 1 } } or
>   function{ pattern{ agate warp{repeat x } } } (afaik both are valid)

Well, I didn't know that either.  I have changed the FLOAT_USER_FUNCTION
syntax, the pattern part, to the following:
    function { pattern { PATTERN [PATTERN_MODIFIERS] } }

I have also modified the PATTERN syntax to look like this:
    MAP_PATTERN  |  brick [BRICK_ITEMS]  |  checker  |  hexagon  |  object
{ LIST_OBJECT }

The same change was made to the appropriate BITMAP_IMAGE items.  That would
be in section 10.1.10.8 Pattern Modifiers in the docu.

Thanks for finding these.  Let me know if anything else needs to be
corrected.

Robert Chaffe
http://www.donovansweb.com/~chaffe/


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