So, no more opinions on this proposed change? /Roman
Am Dienstag, den 12.08.2008, 13:29 +0200 schrieb Roman Kennke: > Hi there, > > I have a small problem with current implementation of fonts in OpenJDK. > It is required that fonts are present as files, and that all fonts are > loaded via a FileChannel, not InputStream, because FreeType doesn't > support loading from a sequential-only stream. From my perspective as > embedded VM developer this is not very practical. Ideally I'd like to be > able to embed fonts in the classpath (with the Jamaica VM you can create > a complete image of an application+VM+resources and don't need anything > else on the target machine, sometimes not even a filesystem). I can't do > that using the current approach in OpenJDK. I have some ideas how to > change it, and I think there are also some advantages for the more > general OpenJDK community. Here's my plan which I'd like to discuss: > > - Change TrueTypeFont and all related classes (these are a lot) to read > from a (direct) ByteBuffer, instead of a file channel. FreeType can read > fonts directly from a memory buffer, this would make a lot of code > easier (i.e. freetypeScaler.c wouldn't need these callbacks). > - At a slightly higher level, don't pass FileChannels to TrueTypeFont to > read from, but instead map the file, and pass the resulting buffer. I'm > not sure about all the OS level details, but I think it is possible that > the OS does some interesting optimizations here. For example, if the OS > already has the font file open (for the desktop), this can be reused, > and should be faster than reading into a new buffer. > - File.createFont(InputStream) could be changed to read from the stream > into a memory buffer, instead of a temporary file. > > For me personally, this means that I could access the app+VM+resources > image directly using a (direct) ByteBuffer and pass that to read fonts > from the classpath, thus solving my problem. > > What do you think about this rough outline? Maybe you have other ideas > how to solve my problem? Would such a change have a chance to be > accepted into OpenJDK mainline? (I'd try hard to avoid having to > maintain a fork of the code.) > > Kind regards, Roman -- Dipl.-Inform. (FH) Roman Kennke, Software Engineer, http://kennke.org aicas Allerton Interworks Computer Automated Systems GmbH Haid-und-Neu-Straße 18 * D-76131 Karlsruhe * Germany http://www.aicas.com * Tel: +49-721-663 968-48 USt-Id: DE216375633, Handelsregister HRB 109481, AG Karlsruhe Geschäftsführer: Dr. James J. Hunt
