L. Spiro

Vulkan Vulkan Resources

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FYI the AMD drivers are partially broken, at least on my 290X. There's something wrong with their ICD implementation, there are posts on the internal AMD developer forum about the issue.

 

EDIT: Never mind. I went to go check on the status of this and it looks like AMD has issued a hotfix.

Edited by InvalidPointer

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https://github.com/SaschaWillems/Vulkan

 

Is it just me or are most of the samples doing a ton of unnecessary waiting? 

 

With the exception maybe doing something quick and dirty, special blocking loads, or maybe something fancy I can't think of at the moment, I kind of assume one wouldn't want to call vkDeviceWaitIdle or vkQueueWaitIdle very frequently. Right? But they seem littered everywhere.

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Is it just me or are most of the samples doing a ton of unnecessary waiting? 

 

With the exception maybe doing something quick and dirty, special blocking loads, or maybe something fancy I can't think of at the moment, I kind of assume one wouldn't want to call vkDeviceWaitIdle or vkQueueWaitIdle very frequently. Right? But they seem littered everywhere.

 

It's a hell of a lot easier than setting up the infrastructure for double (or more) buffering, where you need to ensure that you don't change/delete things that are being used for the previous frame.  You still need to issue a wait every 2 frames for double buffering (3 for triple buffering, and so on), but in practice, it's just there as a safeguard for pathological scenarios and should typically be a no-op.

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I'm kinda excited for it, but with my limited openGL experience I'll be sticking with openGL for now. Definitely coming back to this in the future though, to learn more about those extra control goodies.

There's very little that looks anything like GL. It looks a whole lot like DX12 however.

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Just as a heads up; Khronos have a couple of low-resolution versions of the GDC presentations up on youtube, while the slides are readable it is currently suffering from some horrible audio drop out (around the 1 hour mark you basically can't hear anything), which is not overly helpful when it comes to trying to hear about memory allocation.

I'm hoping it'll be fixed in the high resolution version, but I'm not holding out any hopes... (see comment in other thread about half-arsing things).

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Is there a sampled showing input_attachment usage ? I'm trying to use them but so far it doesn't work (subpassLoad() always returns 0 and there is no debug layer message related to the issue) so I'd like to see a working example.

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I forgot to fill more than one attachment in vkPipelineColorBlendStateCreateInfo ; fixing this makes subpassLoad() work. However this seems unreliable : I have an extra sampler in the pipeline_layout that I used to sample render target before having subpassLoad working but now if I remove it my device is "lost". It might be a geforce driver bug though.

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