4 ms·

Calling Vulkan a failed design is selling it short. There are parts like image layout tracking that should never have been exposed; tracking that at the applica

Calling Vulkan a failed design is selling it short. There are parts like image layout tracking that should never have been exposed; tracking that at the application level does not offer any additional gains. Exposing explicit synchronization, on the other hand, is in principle the right idea. The driver gets information through those APIs that it cannot derive any other way. I believe it enables certain practical resource access patterns that would be near impossible without that. However, there may be a better way than the current pipeline barrier API to describe data and execution dependencies. Other parts of Vulkan are clear wins. Pipelines with their explicit state look more cumbersome than the OpenGL state machine when starting out on a toy renderer, but they are absolutely invaluable in anything slightly more complex. All OpenGL based renderers that I've worked with ended up building a state management abstraction on top of OpenGL to work around the debugging nightmare of forgotten state variable updates. Pipeline add this state management at the driver level.

cyber_kinetist 3y ago
Pipelines (or in general terms PSOs) are the most problematic aspect of Vulkan / DX12 - much more than synchronization! Large parts of the gamedev industry seems to recognize all the performance issues with pipelines and therefore companies are experimenting with newer models like the VK_EXT_shader_object extension ("Vulkan without Pipelines": https://www.khronos.org/blog/you-can-use-vulkan-without-pipelines-today https://www.khronos.org/blog/you-can-use-vulkan-without-pipe...). I've written a detailed comment about this before here (https://news.ycombinator.com/item?id=37843946#37845431 https://news.ycombinator.com/item?id=37843946#37845431) but for a much more comprehensive explanation by an engineer from Nintendo read the initial proposal for the VK_EXT_shader_object extension: https://github.com/KhronosGroup/Vulkan-Docs/blob/main/proposals/VK_EXT_shader_object.adoc https://github.com/KhronosGroup/Vulkan-Docs/blob/main/propos...). And the slightly less-official behind-the-scenes tweet thread about the background for VK_EXT_shader_object: https://twitter.com/gfxstrand/status/1641914602756644867 https://twitter.com/gfxstrand/status/1641914602756644867 There's also Casey Muratori's mail to the Vulkan advisory on 2015 that basically predicts this whole clusterfuck would happen: https://github.com/cmuratori/misc/blob/main/vulkan_dynamic_state.md https://github.com/cmuratori/misc/blob/main/vulkan_dynamic_s...

cyber_kinetist 3y ago

Pipelines (or in general terms PSOs) are the most problematic aspect of Vulkan / DX12 - much more than synchronization! Large parts of the gamedev industry seems to recognize all the performance issues with pipelines and therefore companies are experimenting with newer models like the VK_EXT_shader_object extension ("Vulkan without Pipelines": https://www.khronos.org/blog/you-can-use-vulkan-without-pipelines-today https://www.khronos.org/blog/you-can-use-vulkan-without-pipe...). I've written a detailed comment about this before here (https://news.ycombinator.com/item?id=37843946#37845431 https://news.ycombinator.com/item?id=37843946#37845431) but for a much more comprehensive explanation by an engineer from Nintendo read the initial proposal for the VK_EXT_shader_object extension: https://github.com/KhronosGroup/Vulkan-Docs/blob/main/proposals/VK_EXT_shader_object.adoc https://github.com/KhronosGroup/Vulkan-Docs/blob/main/propos...). And the slightly less-official behind-the-scenes tweet thread about the background for VK_EXT_shader_object: https://twitter.com/gfxstrand/status/1641914602756644867 https://twitter.com/gfxstrand/status/1641914602756644867 There's also Casey Muratori's mail to the Vulkan advisory on 2015 that basically predicts this whole clusterfuck would happen: https://github.com/cmuratori/misc/blob/main/vulkan_dynamic_state.md https://github.com/cmuratori/misc/blob/main/vulkan_dynamic_s...