[magick-users] gradient to transparency

[Bob Meetin]

I see what you noted with .gif.  However, I was also generating a .png 
version with the same problem. gradient:anything-none is producing the 
same output, i.e.  == gradient:anything-anything.   Regardless of the 
color, it is not recognizing "none".  So curious, I checked on another 
hosting server with the same result.  Well now, even more curious I 
tested command-line on my Fedora Linux box and this time it works.  So 
the version of ImageMagick installed on the server is the culprit I guess.

What I am showing for version is:  *Version: ImageMagick 6.0.7 04/19/08 
Q16 http://www.imagemagick.org Copyright: Copyright (C) 1999-2004 
ImageMagick Studio LLC

*-Bob*
*
 Ross Presser wrote:
> Your output is GIF. GIFs don't do an alpha channel -- just a single 
> transparent color as a mask.
>  
> Try PNG output.
>
> On Thu, May 8, 2008 at 2:43 PM, Bob Meetin <bobm at dottedi.biz 
> <mailto:bobm at dottedi.biz>> wrote:
>
>     Anthony, all,   I wrote a PHP script to generate gradients.
>      Looking at
>     it and the output it looks fine, but color to transparent is not
>     working.
>
>     http://www.dottedi.biz/tools/gradient_generator.php
>
>     To test, simple delete any input from the gradient lower or use the
>     color chooser to select "no color".  The php code converts either
>     option
>     to "none". I have it set to echo back the command which of course
>     looks
>     right.  Any thoughts?
>
>     Anthony Thyssen wrote:
>     > "Christoph P. Kukulies" on  wrote...
>     > | I'm seeking for a general solution to allow for producing
>     gradients
>     > | from color to transparency either linearly or (even better) after
>     > | some function (exp or other).
>     > |
>     > | Reason behind is producing shadows for images or weblayouts over
>     > | their respective background image so that I get a smooth
>     > | transition from some opaque shadow to transparency.
>     > |
>     > | Thanks a lot in advance.
>     > |
>     > A vertical linear one is easy...
>     >
>     >    convert -size 100x100 gradient:firebrick-none gradient_trans.png
>