Reverting a merge is sticky: it tells git you never want to see that branch
again. Merging the DRTVWR-546 branch, which contained the revert, into the
glthread branch undid much of the development work on that branch. To restore
it we must revert the revert.
This reverts commit 029b41c041.
It's sometimes important to finish other initialization before launching the
threads in the ThreadPool, so make that an explicit step. In particular, we
were launching the LLImageGL texture thread before initializing the GL
context, resulting in all gray textures.
That is, when LLViewerFetchedTexture::scheduleCreateTexture() wants to call
createTexture() on the LLImageGLThread, but postCreateTexture() on the main
thread, use the "mainloop" WorkQueue to set up the handshake.
Give ThreadPool a public virtual run() method so a subclass can override with
desired behavior. This necessitates a virtual destructor. Add accessors for
embedded WorkQueue (for post calls), ThreadPool name and width (in threads).
Allow LLSimpleton::createInstance() to forward arguments to the subject
constructor.
Make LLImageGLThread an LLSimpleton - that abstraction didn't yet exist at the
time LLImageGLThread was coded. Also derive from ThreadPool rather than
LLThread. Make it a single-thread "pool" with a very large queue capacity.
Use the new WorkQueue::postIfOpen() method in LLImageGLThread::post(). That
makes the LLImageGLThread method a trivial wrapper, which can accept templated
work items and pass them through to the WorkQueue method, eliminating double
indirection due to multiple layers of std::function.
Eliminate LLImageGLThread's WorkQueue intended for work on the main queue.
Since the main loop already has a WorkQueue of its own, post work directly to
that WorkQueue instead of using a separate WorkQueue misleadingly embedded in
LLImageGLThread.
Instead of looking up the main thread's WorkQueue every time, capture a
pointer in LLImageGL's constructor.
We no longer need a fallback queue for when the main thread's WorkQueue is
full. We no longer need the main loop to poll LLImageGL to service the local
main-thread-targeted WorkQueue, or to copy work from the fallback queue to the
main queue. That eliminates LLImageGLThread::postCallback(), mCallbackQueue,
mPendingCallbackQ, executeCallbacks() -- and even LLImageGL::updateClass() and
LLAppViewer's call to it.
Change LLViewerFetchedTexture::scheduleCreateTexture() to post work to the
main thread's WorkQueue instead of calling LLImageGLThread::postCallback().