On Mon, Mar 10, 2003 at 10:36:21PM +0000, Keith Whitwell wrote: > No, because one of the things C++ does is pass around an extra parameter -- > namely the 'self' pointer. The 'real' prototype looks something like: > > void Context::BlendFunc( Context *self, GLenum sfactor, GLenum > dfactor )
I know this, that's why I thought there could be a remote chance to make it work, as the arguments mostly match, i.e., ctx = self. > -- but there's no guarentee that this is actually what is happening, or > that it won't change. Yes, I know there is an ABI now -- but I've no idea > what it actually specifies. That's my doubt too. > >As I said above this can be done in C++, and without damage to > >efficiency. > > Except that the functions plugged into the dispatch table cannot be C++ > methods, as the prototypes are defined, and don't include the magic C++ > self pointer. But the function I put in the table _was_ an ordinary function, and not a C++ method, and no redirection call would take place with inlining. That was the point of the explanation... > I've deleted the rest of your explanation as unfortunately I don't think it > can be made to work. I've deleted the rest of your comment as unfortunately I don't agree with any of it. But I've read it. The principles of doing everything explicitly to achieve better performance are great etc, but at this point we don't have the manpower on DRI to do this kind of development. This is something that is better to rely on C++ to do it for us, as _much_ as possible, even knowing that you could achieve better with explicit C or even assembly coding. This is a burden of higher-level languages. My main priority with the C++ framework is first to _speed_ development. Most of the performance enhancements will be a side-effect for having more free time to optimizate, and being able to do it in a driver-inpendent fashion. And yes, I do believe that, with care, C++ won't create a noticeable overhead, but there's no point to discuss it, as we can simply benchmark it on the end. José Fonseca __________________________________________________ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
