I finally succeeded for references to any PRS-T1 integrated font !
for exemple:
@font-face {
font-family: MyFont1;
font-weight: normal;
font-style: normal;
src: url(res:///ebook/fonts/FrutigerNeueLTW1G-Regular.otf);
}
Don't need to include a copy of these fonts in each ePUB !
See my previous list of filenames for fonts you can directly reference.
And now that I found this, I know that references outside of the ebook content are possible, only have to find how to reference user-visible integrated and external flash.
I can also stop trying urls that don't begin with res:/// !
My sample reference 6 of the PRS-T1 fonts without embedding them (obviously in 2.3KB) plus a failed reference to a font added to internal flash.
FYI, I already tried res:///ebook/mnt/sdcard (in the sample) and res:///ebook/sdcard as READER root, both failed, will do more tests tomorrow.