[vlc-devel] [PATCH 2/2] egl: tune eglTerminate behaviour with display_reference availability

[Rémi Denis-Courmont]

Hi,

If it's a compile-time constant, better keep it a compile time constant than store it in memory IMO.

Le 25 septembre 2019 11:24:40 GMT+03:00, Alexandre Janniaux <ajanni at videolabs.io> a écrit :
>EGL_KHR_display_reference specifies the behaviour of eglTerminate
>with regards to reference counting. In addition, it specifies that
>the default is that reference counting is disabled X11 or wayland,
>but enabled on Android.
>
>As we can prevent EGL GL provider from terminating its state, it
>makes sure the state is correctly refcounted in any case.
>---
> modules/video_output/opengl/egl.c | 23 +++++++++++++++++++++--
> 1 file changed, 21 insertions(+), 2 deletions(-)
>
>diff --git a/modules/video_output/opengl/egl.c
>b/modules/video_output/opengl/egl.c
>index 6d6ab05738f..dd8e0cf9887 100644
>--- a/modules/video_output/opengl/egl.c
>+++ b/modules/video_output/opengl/egl.c
>@@ -58,6 +58,7 @@ typedef struct vlc_gl_sys_t
>     PFNEGLDESTROYIMAGEKHRPROC   eglDestroyImageKHR;
> 
>     bool prevent_terminate;
>+    bool has_display_reference;
> } vlc_gl_sys_t;
> 
> static int MakeCurrent (vlc_gl_t *gl)
>@@ -188,8 +189,10 @@ static void Close(vlc_gl_t *gl)
>         if (sys->surface != EGL_NO_SURFACE)
>             eglDestroySurface(sys->display, sys->surface);
> 
>-        /* Kill the egl state only if we own it. */
>-        if (!sys->prevent_terminate)
>+        /* If has_display_reference == true, sys->display is
>refcounted by
>+         * eglInitialize and eglTerminate, so call it anyway.
>+         * Otherwise, kill the egl state only if we own it. */
>+        if (sys->has_display_reference || !sys->prevent_terminate)
>             eglTerminate(sys->display);
>         eglReleaseThread();
>     }
>@@ -224,6 +227,7 @@ static int Open(vlc_gl_t *gl, const struct gl_api
>*api,
>     sys->surface = EGL_NO_SURFACE;
>     sys->eglCreateImageKHR = NULL;
>     sys->eglDestroyImageKHR = NULL;
>+    sys->has_display_reference = false;
> 
>     vout_window_t *wnd = gl->surface;
>EGLSurface (*createSurface)(EGLDisplay, EGLConfig, void *, const EGLint
>*)
>@@ -234,6 +238,21 @@ static int Open(vlc_gl_t *gl, const struct gl_api
>*api,
>      * the associated EGL display. */
>    sys->prevent_terminate = var_GetBool(wnd, "egl-prevent-terminate");
> 
>+    /* See
>https://www.khronos.org/registry/EGL/extensions/KHR/EGL_KHR_display_reference.txt
>*/
>+    /* If EGL_KHR_display_reference is not present, eglTerminate will
>+     * terminate the EGLDisplay which is shared between all clients.
>+     * This extension turns the behaviour of eglTerminate into
>reference
>+     * counting mode and prevents this issues.
>+     * TODO: currently, we're using the default behaviour of this
>extension. */
>+#ifdef USE_PLATFORM_ANDROID
>+    sys->has_display_reference = true; /* enforced by Android */
>+#else
>+    /* If we don't conditionnaly add the EGL_TRACK_REFERENCE_KHR,
>EGL_TRUE
>+     * parameter to display query parameters, the default is false for
>other
>+     * platforms. */
>+    sys->has_display_reference = false;
>+#endif
>+
> #ifdef USE_PLATFORM_X11
>     sys->x11 = NULL;
> 
>-- 
>2.23.0
>
>_______________________________________________
>vlc-devel mailing list
>To unsubscribe or modify your subscription options:
>https://mailman.videolan.org/listinfo/vlc-devel

-- 
Envoyé de mon appareil Android avec Courriel K-9 Mail. Veuillez excuser ma brièveté.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.videolan.org/pipermail/vlc-devel/attachments/20190925/adc3bea5/attachment.html>