D3200 vs D5200

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In the D5200‘s favour (in roughly decreasing order of importance): In the D3200‘s favour: In neither’s favour: Other notes of interest: What’s not known yet: Update: Nikon have stated it’s an “all new” sensor, from Toshiba (as opposed to the Sony sensor in the D3200).  So it could be interesting.  There’s no particular reason to believe it’s… Read more

SceneKit & shaders

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Note: Since writing this originally I’ve figured out how to get at least some aspects of shaders working.  I’m still trying to flesh out the rest.  I’ll post an update or revised entry at some point. Ugh.  SceneKit supports shaders, technically.  But it’s almost unequivocally unusable.  Let me count the reasons: It doesn’t support geometry shaders… Read more

SCNSphere can be expensive to recreate

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In a current project I’m drawing hundreds of spheres, of varying sizes.  I discovered at one point that with them all in view simultaneously, performance was very bad (<10 FPS on my 6970M).  Trial and error revealed that changing the geometry complexity – by changing the segment count of my spheres – made a huge difference.… Read more

SCNView can have overlapping views, but only if layer-backed

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In fact I’m pretty sure this behaviour dates back to NSOpenGLView and possibly others.  I suppose technically this has always been the case; that overlapping views weren’t supported at all before layer-backing.  But I had forgotten, so it took a little bit of experimenting to jog my memory. It’s interesting that when not layer-backed, all… Read more

+[SCNTransaction setCompletionBlock:] always invokes the block immediately

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It’s supposed to invoke your block when all the animations in the current transaction have completed. It doesn’t; it runs it as soon as the transaction is committed. Le sigh. It does appear to do it from the main runloop at least, as documented. So there is technically a delay, as a consequence of that… Read more