I have made the following "working" example:
Still have a few questions at the bottom left.
...
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# part of example script
####################
print "Create 3D ball ...\n";
$img=Image::Magick->new;
$img->Set(size=>'500x500');
$x=$img->ReadImage('xc:white');
warn "$x" if "$x";
my ($center_x,$center_y,$radius)=(200,200,200);
$img->Draw(fill => 'red', points => "$center_x,$center_y @{[$center_x + $radius]},$center_y", primitive => 'circle' );
#
# create a radial white spot
#
$example=Image::Magick->new;
$example->Set(size=>'150x150');
$x=$example->ReadImage('radial-gradient:white-red');
warn "$x" if "$x";
# put it together in one image
$img->Composite(image=>$example,compose=>'over',geometry=>'+45+75');
# write it to a file:
$img->Write('perlmagickdemo.jpg');
http://digirent.nl/images/perlmagickdemo.jpg
# Questions left on the samen example:
###################
# is it possible to use Composite and only use a cirkel of the $example ? Now it copies the complete square
# is it possible to get a more 3d looking effect on the border of the red cirkel and how to realize that?
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