Lion GL Quad Structure & Image input in Trackball

cybero's picture

I've recently being corresponding off list regarding how to efficiently structure texture co ordinates into a received structure of x,y,z members.

In doing so, I stumbled across what looked like initally to be a bug either with GL Tools or Lion itself, or how GL Tools works with Lion frameworks.

As follows ...

Create a quad structure. Feed into Quad structure input on a GL Tools Quad Structure patch, placed within a Trackball.

Result, renders OK.

Place another GL Tools Quad Structure patch in the trackball, without inputting the image feed , result renders OK.

Feed both Quad patches with the image feed inside the Trackball, result, barely begins to render at all, sometimes crashing or requiring a Force Quit.

Feed both Quad patches with the image feed outside the Trackball, result, renders OK.

Imagine my surprise when I transmutated the external patches into a Trackball -- and they rendered OK.

The real stumbling block wasn't textures being fed into the quad structures, per se, but that the Trackball only works when fed with structure and image feeds set externally to the recipient patches contained within the Trackball

See attached file. :-)

Interesting point , regarding the slight structural change now seemingly required in Lion, is that no such external feed is required in Snow, the Trackball happily receiving the image and structure feeds from patches placed within the Trackball.

Whatever, can anyone else confirm this?

LionGLQuadTrackballProblem.qtz7.78 KB

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cybero's picture
Re: Lion GL Quad Structure & Image input in Trackball

An additional twist to this problem, which looks more and more likely to be the product of Lion not handling Image input within a Trackball as well as it handles Image input from without onto a Trackball contained object.

Does not seem to be a GL Tools only problem as such,[at all], but rather to do with some subtle difference between how Snow and Lion handle texture inputs / image inputs to objects within Trackball patches. Especially video inputs.

I have been able to reduce this problem down to having only one Quad Structure patch in a Trackball [with a video image input].

Starting and stopping such a composition, even when the image input is located external to Trackball is also a real drag, causing a lot of churn.

I am also looking at how stable my overall installation base is, just in case, but thus far, there doesn't seem to be any real cause for concern as such on that front.

Just about to reinstall xCode upon a fresh Lion installation.


Post xCode installation - running the attached composition , I found that enabling and disabling the video input worked OK, but actually ceasing and restarting the composition really causes a reproducible churn. The Viewer window fails to reach a point of rendering at all, until Force Quit, then the Viewer will flash into life before I confirm to quit.

Also , trying to start the composition with Video flagged also reproduces the hang, whilst enabling once the Image input is rendering, will make the video work.

This isn't all part and parcel of what underlying cause is giving rise to the current difficulty in Lion with the Movie Importer patch is it?

The reason that I ask that is merely because I often as not find that switching the Movie Importer patch to Asynchronous mode can often get it to play in a live render situation, even though it won't spark up correctly when simply required to commence rendering at the start time of a composition.

Quite definitely to do with some current in Lion deficiency with QC's handling of animated / movie / video image inputs. It's pretty frustrating finding that a stock patch like Video input and Movie Importer are failing to function correctly within QC 4.5, although, as I posted elsewhere, a QC composition bundling a movie , like the 1961 demo from manwe, works just fine.

Definitely QC 4.5 localised and not specifically to do with even the eponymous framework, I would have thought, or surely it would spit it's dummy out at such a QC framework, movie bundling dependent application.

LionGLQuadTrackballProblem_1.qtz329.78 KB
LionGLQuadTrackballProblem_2.zip538.19 KB