Commit 8bce03e3 authored by Gerd Hoffmann's avatar Gerd Hoffmann
Browse files

ui/egl-helpers: fix egl 1.5 display init 



Unfortunaly switching to getPlatformDisplayEXT isn't as easy as
implemented by 0ea1523f.  See the
longish comment for the complete story.

Cc: Frediano Ziglio <fziglio@redhat.com>
Suggested-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
Message-id: 1489997042-1824-1-git-send-email-kraxel@redhat.com
parent db6cd4c8

ui/egl-helpers.c

+52 −6
Original line number Diff line number Diff line
@@ -192,6 +192,56 @@ EGLSurface qemu_egl_init_surface_x11(EGLContext ectx, Window win) 


/* ---------------------------------------------------------------------- */



/*

 * Taken from glamor_egl.h from the Xorg xserver, which is MIT licensed

 *

 * Create an EGLDisplay from a native display type. This is a little quirky

 * for a few reasons.

 *

 * 1: GetPlatformDisplayEXT and GetPlatformDisplay are the API you want to

 * use, but have different function signatures in the third argument; this

 * happens not to matter for us, at the moment, but it means epoxy won't alias

 * them together.

 *

 * 2: epoxy 1.3 and earlier don't understand EGL client extensions, which

 * means you can't call "eglGetPlatformDisplayEXT" directly, as the resolver

 * will crash.

 *

 * 3: You can't tell whether you have EGL 1.5 at this point, because

 * eglQueryString(EGL_VERSION) is a property of the display, which we don't

 * have yet. So you have to query for extensions no matter what. Fortunately

 * epoxy_has_egl_extension _does_ let you query for client extensions, so

 * we don't have to write our own extension string parsing.

 *

 * 4. There is no EGL_KHR_platform_base to complement the EXT one, thus one

 * needs to know EGL 1.5 is supported in order to use the eglGetPlatformDisplay

 * function pointer.

 * We can workaround this (circular dependency) by probing for the EGL 1.5

 * platform extensions (EGL_KHR_platform_gbm and friends) yet it doesn't seem

 * like mesa will be able to advertise these (even though it can do EGL 1.5).

 */

static EGLDisplay qemu_egl_get_display(void *native)

{

    EGLDisplay dpy = EGL_NO_DISPLAY;



#ifdef EGL_MESA_platform_gbm

    /* In practise any EGL 1.5 implementation would support the EXT extension */

    if (epoxy_has_egl_extension(NULL, "EGL_EXT_platform_base")) {

        PFNEGLGETPLATFORMDISPLAYEXTPROC getPlatformDisplayEXT =

            (void *) eglGetProcAddress("eglGetPlatformDisplayEXT");

        if (getPlatformDisplayEXT) {

            dpy = getPlatformDisplayEXT(EGL_PLATFORM_GBM_MESA, native, NULL);

        }

    }

#endif



    if (dpy == EGL_NO_DISPLAY) {

        /* fallback */

        dpy = eglGetDisplay(native);

    }

    return dpy;

}



int qemu_egl_init_dpy(EGLNativeDisplayType dpy, bool gles, bool debug)

{

    static const EGLint conf_att_gl[] = {
@@ -222,12 +272,8 @@ int qemu_egl_init_dpy(EGLNativeDisplayType dpy, bool gles, bool debug) 
        setenv("LIBGL_DEBUG", "verbose", true);

    }



    egl_dbg("eglGetDisplay (dpy %p) ...\n", dpy);

#ifdef EGL_MESA_platform_gbm

    qemu_egl_display = eglGetPlatformDisplayEXT(EGL_PLATFORM_GBM_MESA, dpy, NULL);

#else

    qemu_egl_display = eglGetDisplay(dpy);

#endif

    egl_dbg("qemu_egl_get_display (dpy %p) ...\n", dpy);

    qemu_egl_display = qemu_egl_get_display(dpy);

    if (qemu_egl_display == EGL_NO_DISPLAY) {

        error_report("egl: eglGetDisplay failed");

        return -1;