A draft merge request has been opened to land “Copper” in Mesa.
Copper was created last year by Adam Jackson of Red Hat with input from Mike Blumenkrantz and others. This DRI interface extension can lead to much greater efficiency for Zink, OpenGL implementation on Vulkan and native WSI handling for it. Copper would help improve the Gallium3D architecture and bring substantial benefits to Zink.
On Thursday, Blumenkrantz opened the MR project for the Copper merge in hopes of getting the code into shape for mainlining, but not necessarily in the immediate future. Pushing Copper out as a longer-term effort depends on other open merge requests such as Zink external memory support, sparse textures, and other bits.
Blumenkrantz summarized Copper’s work in the merge request as “The copper interface was designed by [Adam Jackson] then hacked into existence by me. Its premise is that it provides a minimal amount of display server information to zink (essentially everything needed to successfully create a swap chain), then zink passes it to Vulkan [WSI, windowing system integration]. this means it ignores almost all dri2/3 in the frontend and is somewhat close to the existing swrast code path… In my tests everything “works” now. I think there are a few piglit tests that fail (X pixmap nonsense or whatever), but even more miraculously pass. The only thing that definitely doesn’t work is running any kind of xserver because glamor is hard.”
Zink, Copper, and Penny have been among the names of Mesa subprojects lately, all of which are closely related.
Blumenkrantz continues to work on this Zink OpenGL-on-Vulkan implementation for Valve. He also wrote a short blog post on Copper’s merger request.
