On 06/13/2016 01:58 AM, Collin Anderson wrote: > This same behavior occurs on my OS X box as well. It also has coordinate > transformation issues if you try to lower the size of the window. Here, > rather than try and describe it, here is a gif (frame rate is low in the gif, > it is not choppy in reality): https://metacollin.com/resize.gif > > I have been using OpenGL for years with limited success ( old but probably > best demo that I may, in fact, not be full of crap ;) > https://www.youtube.com/watch?v=SGddIJBAEUk ) and I've been glancing at the > code for anything obvious, and I did find one problem: > > In the constructor for OPENGL_GAL: > > if( glMainContext == NULL ) > { > glMainContext = GL_CONTEXT_MANAGER::Get().CreateCtx( this ); > glPrivContext = glMainContext; > shader = new SHADER(); > } > else > { > glPrivContext = GL_CONTEXT_MANAGER::Get().CreateCtx( this, > glMainContext ); > } > > > This looks dangerous. I might be wrong, KiCad's code base is ....non-trivial > :). So maybe there is no problem here, but if glMainContext is not NULL, is > it guaranteed to be 'virgin' at this point? OpenGL contexts must be totally > fresh when they are shared - you cannot make any opengl calls in any context > until after you've created a shared context (if you are going to). In other > words, one would be expected to call the function that ultimately creates a > new context that is shared with another one immediately after that other one > has been created. > > i.e. > > glMainContext = GL_CONTEXT_MANAGER::Get().CreateCtx( this ); // the main > context > glPrivContext = GL_CONTEXT_MANAGER::Get().CreateCtx( this, glMainContext ); > // Must create your shared context immediately after, before any OpenGL calls > are made to the main context > > Again, maybe that is exactly what will ultimately happen, I didn't get a > chance to look at the higher level code to check. Hopefully someone who > knows what is going on can say for sure though. > > Anyway, I'll keep going through the code as time permits, at least while > things are still broken OpenGLwise.
Hi Collin, I may modify the code to assure that contexts are shared in the way you describe, but would you point me to a relevant documentation that says so? I have grepped the OpenGL 2.1 specification [1] with 'shar' and 'context' and I could not find any notice that requires the main context to be untouched before another shared context is created. Thank you in advance, Orson 1. https://www.opengl.org/registry/doc/glspec21.20061201.pdf
signature.asc
Description: OpenPGP digital signature
_______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : kicad-developers@lists.launchpad.net Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
