Yeah that's the doc page that got me worried/confused. The critical section indeed seems completely unnecessary as well.
Thanks for your help. On Tue, May 1, 2012 at 4:16 PM, Ben Houston <[email protected]> wrote: > I assume you are referring to this: > > > http://softimage.wiki.softimage.com/sdkdocs/cb_Renderer_Abort.htm#Rzmcb_Renderer_Abort > > Currently we are not locking and unlocking the scene, but may be we > should be. I will look into that. I guess if the user modifies the > scene during our data query, they could get inconsistent results, but > it is just a preview so I am not sure that is the end of the world > unless it causes a crash. I must admit I am not that clear on what > scene locks are. > > I think the critical section around a boolean is unnecessary > personally. A boolean is already atomic generally and you don't need > perfect synchronization for an abort process. > > -ben > > On Tue, May 1, 2012 at 7:10 PM, Nicolas Burtnyk <[email protected]> > wrote: > > That part I get. I guess I'm confused by some of the statements in the > docs > > about calling UnlockScene before checking the abort flag and by the > example > > code which seems to use a simple abort flag in some cases and a Win32 > Event > > in others. > > > > > > On Tue, May 1, 2012 at 3:56 PM, Ben Houston <[email protected]> wrote: > >> > >> A very easy way of using it would be to set a global boolean > >> somewhere, such as "bool gAbortRequested" on start of render to > >> "false". Then check it periodically on your render thread. When > >> abort is called just set gAbordRender to "true" and eventually your > >> renderer thread will check that variable, notice it is "true" and > >> stop. It does take a bit of engineering to make sure it can stop > >> without memory leaks. > >> -ben > >> > >> On Tue, May 1, 2012 at 6:52 PM, Nicolas Burtnyk <[email protected] > > > >> wrote: > >> > Understood - so given that I should use it, how do I use it properly? > >> > > >> > > >> > On Tue, May 1, 2012 at 3:48 PM, Ben Houston <[email protected]> > wrote: > >> >> > >> >> You can technically ignore it, but if your render is long, user's > will > >> >> get annoyed with it and complain. Thus for the best user experience, > >> >> you want to pay attention to it. > >> >> -ben > >> >> > >> >> On Tue, May 1, 2012 at 6:15 PM, Nicolas Burtnyk > >> >> <[email protected]> > >> >> wrote: > >> >> > Hey guys, > >> >> > > >> >> > Does anyone have any experience with the Custom Render Abort > >> >> > callback? > >> >> > I'm confused by some statements and the example code in the docs. > >> >> > > >> >> > The docs say that in response to the abort callback we should halt > >> >> > further > >> >> > processing as soon as possible and return CStatus::Abort from the > >> >> > Process > >> >> > callback. > >> >> > What is an acceptable "as soon as possible"? Obviously we can't > check > >> >> > whether the abort flag is set for every line of code. > >> >> > Are there functions that will fail or hang if used after Abort has > >> >> > been > >> >> > called? Anything else we should be aware of here? For instance is > it > >> >> > technically legal (albeit not nice to the user) to ignore the Abort > >> >> > callback > >> >> > and just keep on extracting data and sending fragments to Soft? > >> >> > > >> >> > Also, I'm confused by this statement in the docs on the Abort > >> >> > callback: > >> >> > "The > >> >> > optimal way of doing this is to unlock the scene graph first, and > >> >> > then > >> >> > check > >> >> > whether the flag has been set, in which case it should stop > >> >> > immediately, > >> >> > otherwise then lock the scene graph again and carry on." What is > the > >> >> > purpose > >> >> > of unlocking the scene graph prior to checking the abort flag? Why > >> >> > not > >> >> > just > >> >> > unlock if we find that the abort flag has been set? > >> >> > > >> >> > Finally, in the ColorRenderer example in the docs, why is the abort > >> >> > check > >> >> > that's done after sending each new fragment waiting on an event > >> >> > rather > >> >> > than > >> >> > simply calling isAborted()? > >> >> > Why the distinction here? > >> >> > > >> >> > Thanks! > >> >> > > >> >> > -Nicolas > >> >> > >> >> > >> >> > >> >> -- > >> >> Best regards, > >> >> Ben Houston > >> >> Voice: 613-762-4113 Skype: ben.exocortex Twitter: @exocortexcom > >> >> http://Exocortex.com - Passionate CG Software Professionals. > >> >> > >> > > >> > >> > >> > >> -- > >> Best regards, > >> Ben Houston > >> Voice: 613-762-4113 Skype: ben.exocortex Twitter: @exocortexcom > >> http://Exocortex.com - Passionate CG Software Professionals. > >> > > > > > > -- > Best regards, > Ben Houston > Voice: 613-762-4113 Skype: ben.exocortex Twitter: @exocortexcom > http://Exocortex.com - Passionate CG Software Professionals. > >
