Date:  11/15/2001 08:52:09 AM Msg ID:  000120
From:  Richard Day Thread:  000118
Subject:  Re: External Libraries and FoxWeb
When you say you want to make use of a compiled library from FoxPro, are you referring to an FLL or a DLL? If so, that shouldn't be a problem, I am currently using an FLL for NetWare network access in a production FoxWeb system. I haven't needed to yet, but you should also be able to call a DLL function from a FoxWeb script as well.

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Richard Day
IS Administrator
Paragon Engineering Services, Inc.
Houston, TX

Sent by NoSpam ForMe on 11/14/2001 03:37:34 PM:
Hi all,

This is a tough one.  Pardon the lengthy explanation.

I'm working on developing a site that requires dynamic modificaiton of graphic elements on the server side before being sent to the browser for display.  Think of it like overlaying cities and points-of-interests on a blank map.  The original graphic files are the blank maps  The elements that I wish to overlay on top of these existing graphics are the cities.  The program will return to the browser a completed graphic.  From the browser's point of view, it is getting a graphic file from the server like any other graphic element via the <IMG> tag.

The process goes like:
1 - read the blank graphic element (map) into memory. 
2 - modifiy it (add the cities to the map in memory)
3 - stream it to the browser as a graphic element.

Because our "friends" at Unisys and IBM have asserted their patents and wish to charge for using GIF, I've chosen to use the PNG format instead.  Unfortunately, there is no PNG source code out there other than the PNG library which, seemingly, everyone in the world uses. 

The challenges:
*  The PNG library source code does not lend itself to translation to FoxPro.
*  Even if it did (which, I assure you, it doesn't), executing so much code for each element would result in very slow web response times.

The problem (at last):
I would like to link the compiled form of the PNG library and make use of it from FoxWeb scripts.  I can do this for compiled _FoxPRO_ programs, but I have no idea of how to include an external library such that FoxWeb scripts "see" them and make use of the commands therein. 

Any ideas/help would be greatly appreciated.  (I would name children after you!)