[GRASSLIST:2301] Re: Poor quality PNG file driver output

[Markus Neteler]

On Mon, Jan 19, 2004 at 07:12:16AM +0000, Glynn Clements wrote:
> 
> Jason Horn wrote:
> 
> > As for re-compiling grass, I'm not sure if I could do it.  I am using 
> > 5.0.2 off of the OpenOSX CD because I'm not an expert with UNIX.  It 
> > was a two-day ordeal for me to get the gd library compiled and running 
> > on my system.  However, I would try to compile it (and all the other 
> > libraries that go with it) if I thought it would help.  So, for Hamish, 
> > or anyone else who can help...
> > 
> > 1) Why do you think re-compiling would help?  I wouldn't want to waste 
> > days on that endeavor if it wouldn't work.
> 
> If the PNG driver was built using GD 1.x, it will use GD 1.x at
> run-time (or fail to run if GD 1.x can't be found). There isn't any
> way to make it use GD 2.x without re-compiling it.
> 
> The quote from Markus' book:
> 
> 	"If the Gd2.x library is installed the driver supports true
> 	color output"
> 
> isn't entirely accurate. The determining factor is whether the driver
> was built with GD 2.x, not whether GD 2.x happens to be present on the
> system.

The next edition of the book will not have this sentence any more
as it is related to GRASS 5.3 (which contains a PNG driver without
the need of GD, thanks to Glynn Clements).

Markus Neteler

-- 
Markus Neteler     <neteler itc it>       http://mpa.itc.it
ITC-irst -  Centro per la Ricerca Scientifica e Tecnologica
MPBA - Predictive Models for Biol. & Environ. Data Analysis
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