Re: Can't hook into the Double Buffer extension.
On Tue, Sep 16, 2014 at 10:41 AM, Adam Jackson a...@nwnk.net wrote: On Fri, 2014-09-12 at 14:59 -0400, Stirling Westrup wrote: I am writing a video driver for which I'd like to support the Double Buffer Extension. However I need to hook some of the calling functions described xorg/dbestruct.h, especially 'AllocateBackBuffer' and 'SwapBuffers'. You found an app that uses it? Impressive. Not so surprising. I wrote the app. Basically we're trying to get frame-perfect synchronization across 16 instantiations of Xorg, all running on one server and talking via USB to 16 zero clients. Its a software-based video wall, and it works decently well. Alas the zero clients don't have either GL or DRI support, so I'm having to go old school with what extensions I use. The plan was to use the X Synchronization library and the DBE to time the frame changes in the video wall, but both of these have API issues and would need patches. (You can't currently create a new class of clock for X Sync). At the moment, yeah. Not so much out of malice as neglect, the extension is not widely used and none of the open (or closed!) drivers attempts to support it specially. I wouldn't object to a patch, although I'd at least like to see it done with accessor functions that return the window/screen private pointer rather than by exporting the private keys. That would be my approach as well, were I to write a patch. Currently the 'improved frame sync' feature for our wall is on hold due to more critical issues in our product which have recently turned up. When we get back to it, I'll submit some patches for X Sync and DBE. Ideally we'd do what the GLX spec says and unify the view of the back buffer across extensions, which I guess could include DRI3 at this point. I'm not very much up on either the GLX or DRI specs, so I'm not sure how that would affect the design of the interfaces. -- Stirling Westrup Programmer, Entrepreneur. https://www.linkedin.com/e/fpf/77228 http://www.linkedin.com/in/swestrup http://technaut.livejournal.com http://sourceforge.net/users/stirlingwestrup ___ xorg@lists.x.org: X.Org support Archives: http://lists.freedesktop.org/archives/xorg Info: http://lists.x.org/mailman/listinfo/xorg Your subscription address: %(user_address)s
Re: Can't hook into the Double Buffer extension.
On Tue, Sep 16, 2014 at 10:41 AM, Adam Jackson a...@nwnk.net wrote: On Fri, 2014-09-12 at 14:59 -0400, Stirling Westrup wrote: I am writing a video driver for which I'd like to support the Double Buffer Extension. However I need to hook some of the calling functions described xorg/dbestruct.h, especially 'AllocateBackBuffer' and 'SwapBuffers'. You found an app that uses it? Impressive. Not so surprising. I wrote the app. Basically we're trying to get frame-perfect synchronization across 16 instantiations of Xorg, all running on one server and talking via USB to 16 zero clients. Its a software-based video wall, and it works decently well. Alas the zero clients don't have either GL or DRI support, so I'm having to go old school with what extensions I use. The plan was to use the X Synchronization library and the DBE to time the frame changes in the video wall, but both of these have API issues and would need patches. (You can't currently create a new class of clock for X Sync). At the moment, yeah. Not so much out of malice as neglect, the extension is not widely used and none of the open (or closed!) drivers attempts to support it specially. I wouldn't object to a patch, although I'd at least like to see it done with accessor functions that return the window/screen private pointer rather than by exporting the private keys. That would be my approach as well, were I to write a patch. Currently the 'improved frame sync' feature for our wall is on hold due to more critical issues in our product which have recently turned up. When we get back to it, I'll submit some patches for X Sync and DBE. Ideally we'd do what the GLX spec says and unify the view of the back buffer across extensions, which I guess could include DRI3 at this point. I'm not very much up on either the GLX or DRI specs, so I'm not sure how that would affect the design of the interfaces. -- Stirling Westrup Programmer, Entrepreneur. https://www.linkedin.com/e/fpf/77228 http://www.linkedin.com/in/swestrup http://technaut.livejournal.com http://sourceforge.net/users/stirlingwestrup ___ xorg-devel@lists.x.org: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: http://lists.x.org/mailman/listinfo/xorg-devel
Re: Can't hook into the Double Buffer extension.
On Fri, 2014-09-12 at 14:59 -0400, Stirling Westrup wrote: I am writing a video driver for which I'd like to support the Double Buffer Extension. However I need to hook some of the calling functions described xorg/dbestruct.h, especially 'AllocateBackBuffer' and 'SwapBuffers'. You found an app that uses it? Impressive. However, the only way to access them is via the private key for dbe, and its not exported. Am I missing something, or is it really impossible to hook those functions? At the moment, yeah. Not so much out of malice as neglect, the extension is not widely used and none of the open (or closed!) drivers attempts to support it specially. I wouldn't object to a patch, although I'd at least like to see it done with accessor functions that return the window/screen private pointer rather than by exporting the private keys. Ideally we'd do what the GLX spec says and unify the view of the back buffer across extensions, which I guess could include DRI3 at this point. - ajax ___ xorg@lists.x.org: X.Org support Archives: http://lists.freedesktop.org/archives/xorg Info: http://lists.x.org/mailman/listinfo/xorg Your subscription address: %(user_address)s
Re: Can't hook into the Double Buffer extension.
On Fri, 2014-09-12 at 14:59 -0400, Stirling Westrup wrote: I am writing a video driver for which I'd like to support the Double Buffer Extension. However I need to hook some of the calling functions described xorg/dbestruct.h, especially 'AllocateBackBuffer' and 'SwapBuffers'. You found an app that uses it? Impressive. However, the only way to access them is via the private key for dbe, and its not exported. Am I missing something, or is it really impossible to hook those functions? At the moment, yeah. Not so much out of malice as neglect, the extension is not widely used and none of the open (or closed!) drivers attempts to support it specially. I wouldn't object to a patch, although I'd at least like to see it done with accessor functions that return the window/screen private pointer rather than by exporting the private keys. Ideally we'd do what the GLX spec says and unify the view of the back buffer across extensions, which I guess could include DRI3 at this point. - ajax ___ xorg-devel@lists.x.org: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: http://lists.x.org/mailman/listinfo/xorg-devel
Can't hook into the Double Buffer extension.
I am writing a video driver for which I'd like to support the Double Buffer Extension. However I need to hook some of the calling functions described xorg/dbestruct.h, especially 'AllocateBackBuffer' and 'SwapBuffers'. However, the only way to access them is via the private key for dbe, and its not exported. Am I missing something, or is it really impossible to hook those functions? -- Stirling Westrup Programmer, Entrepreneur. https://www.linkedin.com/e/fpf/77228 http://www.linkedin.com/in/swestrup http://technaut.livejournal.com http://sourceforge.net/users/stirlingwestrup ___ xorg@lists.x.org: X.Org support Archives: http://lists.freedesktop.org/archives/xorg Info: http://lists.x.org/mailman/listinfo/xorg Your subscription address: %(user_address)s
Can't hook into the Double Buffer extension.
I am writing a video driver for which I'd like to support the Double Buffer Extension. However I need to hook some of the calling functions described xorg/dbestruct.h, especially 'AllocateBackBuffer' and 'SwapBuffers'. However, the only way to access them is via the private key for dbe, and its not exported. Am I missing something, or is it really impossible to hook those functions? -- Stirling Westrup Programmer, Entrepreneur. https://www.linkedin.com/e/fpf/77228 http://www.linkedin.com/in/swestrup http://technaut.livejournal.com http://sourceforge.net/users/stirlingwestrup ___ xorg-devel@lists.x.org: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: http://lists.x.org/mailman/listinfo/xorg-devel
