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A comment on Vulkan Tutorial. Parent comment

Re:Vulkan Tutorial by pcwalton on Tuesday July 19, 2016 @01:26PM (#12123205)
> It's pretty clear what is it for if you actually wrote real-time graphics. JFYI - it's "index shader" essentially. Having control over indices you can implement much faster culling.

This sounds like indirect draw, which has been standard for years and is supported by Vulkan.

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Re:Vulkan Tutorial by pandaman on Tuesday July 19, 2016 @01:52PM (#12123438)
Indirect draw is a draw, which instead of direct arguments (number of indices, number of instances, offsets) takes an address of a structure with these parameters. It does not create indices. You could use it for culling but only on the level of a whole draw. DispatchDraw generates indices in a shader and can do a triangle level culling among other things.
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Re:Vulkan Tutorial by pcwalton on Tuesday July 19, 2016 @07:47PM (#12125806)
> It does not create indices

You combine it with a Compute Shader to create the indices. Indirect draw is how you make those indices available to the drawing functionality.

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Re:Vulkan Tutorial by pandaman on Tuesday July 19, 2016 @08:53PM (#12126113)
Sure, it's possible, but it would be much slower(just for going off chip, not taking synchronization into account) than just letting all triangles through so it has no practical application. Again, even if this had been practical, it does not make DD same as ID. You can draw anything with OpenGl 1.0 but it does not make it the same API as Vulcan, does it?
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