On Tue, 4 Nov 2014 23:42:43 +0100 Marek Olšák <mar...@gmail.com> wrote:
> Hi everybody, > > I'm about to address this long-standing issue: The EGL state tracker is > redundant. It duplicates what st/dri does and it also duplicates what > the common loader egl_dri2 does, which is used by all classic drivers > and even works better with gallium drivers. > > Let's compare EGL extensions for both backends: > > st/egl: > EGL version string: 1.4 (Gallium) > EGL client APIs: OpenGL OpenGL_ES OpenGL_ES2 OpenVG > EGL extensions string: > EGL_WL_bind_wayland_display EGL_KHR_image_base EGL_KHR_image_pixmap > EGL_KHR_image EGL_KHR_reusable_sync EGL_KHR_fence_sync > EGL_KHR_surfaceless_context EGL_NOK_swap_region > EGL_NV_post_sub_buffer > > egl_dri2: > EGL version string: 1.4 (DRI2) > EGL client APIs: OpenGL OpenGL_ES OpenGL_ES2 OpenGL_ES3 > EGL extensions string: > EGL_MESA_drm_image EGL_MESA_configless_context EGL_KHR_image_base > EGL_KHR_image_pixmap EGL_KHR_image EGL_KHR_gl_texture_2D_image > EGL_KHR_gl_texture_cubemap_image EGL_KHR_gl_renderbuffer_image > EGL_KHR_surfaceless_context EGL_KHR_create_context > EGL_NOK_swap_region EGL_NOK_texture_from_pixmap > EGL_CHROMIUM_sync_control EGL_EXT_image_dma_buf_import > EGL_NV_post_sub_buffer > > egl_dri2 also supports MSAA on the window framebuffer (through st/dri). > It's really obvious which one is better. I am slightly surprised you do not get EGL_WL_bind_wayland_display on DRI2. Wonder why that is... Other things not in your dri2 that are in gallium are KHR_reusable_sync and KHR_fence_sync. Does that matter? > I'm aware of 2 features that we will lose: > - swrast on Wayland - I'm not sure about this. Perhaps kms-swrast has > addressed this already. I don't think it does. Isn't kms-swrast about the EGL DRM/KMS platform but using dumb buffers with software rendering instead of real acceleratable buffers? That is, it could be used by Wayland display servers, but not Wayland apps. I don't think that has anything to do with the EGL Wayland platform that is used by applications on Wayland. I am not aware of anything else than egl_gallium.so implementing the glue for doing software rendering into wl_shm-based buffers, which do not need *any* special support from the display server. This means that the server does not need to use EGL at all while still supporting software-GL in apps. It also allows one to use a non-Wayland supporting EGL implementation to accelerate compositing in the server, while still supporting software rendered GL apps. In other words, I believe that removing egl_gallium.so will prevent running GL apps on Wayland with software-GL, like you suspected. I'm not sure how used that is, but every once in a while I explain to someone how to get software-GL going, so I would expect a few upset people from that. I have no clue what it would take to support swrast via wl_shm on EGL Wayland platform with egl_dri2. I tried to ask if the kms-swrast made that any easier, but I was left with the feeling that it doesn't. Swrast on wl_shm would be the sensible thing, but swrast on DRM buffers on Wayland platform would probably be useless, at least until we have a generic dmabuf protocol in place (which is a whole another saga with no end in sight), and it would still explicitly depend on DRM. Personally I like the idea of getting rid of egl_gallium.so, but indeed we do lose some things if that is done right now. Or maybe this would be the kick needed to have someone look at implementing wl_shm support for swrast in egl_dri2... Thanks, pq > - OpenVG - It has never taken off. If people want this on Linux, it should > use egl_dri2 and st/dri, like OpenGL does. > > This series removes st/egl and st/gbm support from the autoconf build > (the latter depends on the former and is probably just as redundant). > The next step is to remove all Linux-specific backends from st/egl. > Windows, Android, and other platform backends will be kept intact, > therefore st/egl won't be removed completely. _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev