"Nemosoft Unv." wrote: > > On 01-Jun-01 Ben Bridgwater wrote: > > "Nemosoft Unv." wrote: > > > >> On 31-May-01 Ben Bridgwater wrote: > > Not really - just add flags to indicate what processor attributes (MMX > > etc) each converter needs, order the accelerated converters before the > > others, then scan the list for the first matching one suported by the > > actual processor attributes. > > > > I'm open to suggestion. > > I would simply replace the function pointer with the most optimized > function during initialization; that way the logic in GetConvertor can be > kept really simple (otherwise, you´d end up with a different GetConvertor on > each platform!). I don't see that. For example, If some converters are flagged as requiring MMX, and a non-x86 CPU is detected by whatever means (conditional compilation and/or /proc/cpuinfo), then the MMX processor attribute would be set false and those converters would never match. Of course we may or may not regardless have to do ./configure (not yet supported!) based conditional compilation if gcc fails on assember that doesn't match -mcpu/arch (I don't know what the behaviour is). Let me see if I can get this out this weekend in it's current form, then we'll have something more concrete to discuss. > > For these formats "to" is useful for X display, and "from" is useful for > > V4L and AVI. You're right that's the way it's implemented - as a bunch > > of individual converters that cover the common XImage formats, but the > > point is that the app can just do a dumb "descriptor.format = PackedRGB, > > descriptor.r/g/b masks = XImage.r/g/b masks", then ask for a converter > > to/from that format. > > So you have a ´general purpose´ convertor that can convert to almost > anything (at the price of being slow, presumably)? More importantly you have an application API that supports general purpose image descriptors, and whether a particular conversion is available is then just a library implementation issue. The application isn't forced to consider individual formats unless it actually wants to. Adding a fallback "general purpose" converter is simple - I'll add one before I release it. Ben
