Which process would you advice to add « drop shadows » to any kind of metafun / metapost figures like:
p := textext("MetaPost is fun!") shifted (10cm,10cm);
My current understanding of the required steps :
1- fill p with the shadow color
2- write it to an external metapost file (with savebuffer ?) ready for png export (outputformat := "png »;)
3- with lua, os.execute, and imagemagick prepare the shadow
- extent the png file with a transparent background, to have room for blurring
- blur it
4- import this png in context / Metapost (externalfigure), and center it with p figure
5- shift it according to the desired shadows distance and angle
6- apply the initial bounding box of p to the shadow, draw the shadow, draw the p picture
Actually, all this seems long and tedious, and contrasts with the already existing links between MetaPost / MetaFun and cairo + libpng.
Thanks again for your help.