wayland/egl: add egl_context to the wayland state

At the moment there are visual glitches when we resize the window. This happens
because in wayland there a special function for resizing EGL windows.

To prevent the glitches move the egl_context to the wayland state in
wayland_common.h and add a new control function to gl_wayland.c to wrap the
vo_wayland_control function to check for resize events.

With the new control wrapper the glitches are gone and the resizing is fluid.

2 files changed, 73 insertions, 67 deletions

diff --git a/video/out/gl_wayland.c b/video/out/gl_wayland.c
index 75f29632b0..e13314f531 100644
--- a/video/out/gl_wayland.c
+++ b/video/out/gl_wayland.c
@@ -16,27 +16,10 @@
  * with mpv.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <wayland-egl.h>
-#include <EGL/egl.h>
-#include <EGL/eglext.h>
-
 #include "wayland_common.h"
 #include "gl_common.h"
 
-struct egl_context {
-    EGLSurface egl_surface;
-
-    struct wl_egl_window *egl_window;
-
-    struct {
-        EGLDisplay dpy;
-        EGLContext ctx;
-        EGLConfig conf;
-    } egl;
-};
-
-static void egl_resize(struct vo_wayland_state *wl,
-                       struct egl_context *ctx)
+static void egl_resize(struct vo_wayland_state *wl)
 {
     int32_t x = wl->window.sh_x;
     int32_t y = wl->window.sh_y;
@@ -45,7 +28,7 @@ static void egl_resize(struct vo_wayland_state *wl,
 
     // get the real size of the window
     // this improves moving the window while resizing it
-    wl_egl_window_get_attached_size(ctx->egl_window,
+    wl_egl_window_get_attached_size(wl->egl_context.egl_window,
                                     &wl->window.width,
                                     &wl->window.height);
 
@@ -60,7 +43,7 @@ static void egl_resize(struct vo_wayland_state *wl,
     if (y != 0)
         y = wl->window.height - height;
 
-    wl_egl_window_resize(ctx->egl_window, width, height, x, y);
+    wl_egl_window_resize(wl->egl_context.egl_window, width, height, x, y);
 
     wl->window.width = width;
     wl->window.height = height;
@@ -74,7 +57,6 @@ static void egl_resize(struct vo_wayland_state *wl,
 }
 
 static bool egl_create_context(struct vo_wayland_state *wl,
-                               struct egl_context *egl_ctx,
                                MPGLContext *ctx,
                                bool enable_alpha)
 {
@@ -83,7 +65,7 @@ static bool egl_create_context(struct vo_wayland_state *wl,
     GL *gl = ctx->gl;
     const char *eglstr = "";
 
-    if (!(egl_ctx->egl.dpy = eglGetDisplay(wl->display.display)))
+    if (!(wl->egl_context.egl.dpy = eglGetDisplay(wl->display.display)))
         return false;
 
     EGLint config_attribs[] = {
@@ -98,7 +80,7 @@ static bool egl_create_context(struct vo_wayland_state *wl,
     };
 
     /* major and minor here returns the supported EGL version (e.g.: 1.4) */
-    if (eglInitialize(egl_ctx->egl.dpy, &major, &minor) != EGL_TRUE)
+    if (eglInitialize(wl->egl_context.egl.dpy, &major, &minor) != EGL_TRUE)
         return false;
 
     MP_VERBOSE(wl, "EGL version %d.%d\n", major, minor);
@@ -112,30 +94,30 @@ static bool egl_create_context(struct vo_wayland_state *wl,
     if (eglBindAPI(EGL_OPENGL_API) != EGL_TRUE)
         return false;
 
-    eglChooseConfig(egl_ctx->egl.dpy, config_attribs,
-                    &egl_ctx->egl.conf, 1, &n);
+    eglChooseConfig(wl->egl_context.egl.dpy, config_attribs,
+                    &wl->egl_context.egl.conf, 1, &n);
 
-    egl_ctx->egl.ctx = eglCreateContext(egl_ctx->egl.dpy,
-                                        egl_ctx->egl.conf,
-                                        EGL_NO_CONTEXT,
-                                        context_attribs);
-    if (!egl_ctx->egl.ctx) {
+    wl->egl_context.egl.ctx = eglCreateContext(wl->egl_context.egl.dpy,
+                                               wl->egl_context.egl.conf,
+                                               EGL_NO_CONTEXT,
+                                               context_attribs);
+    if (!wl->egl_context.egl.ctx) {
         /* fallback to any GL version */
         MP_WARN(wl, "can't create context for requested OpenGL version: "
                     "fall back to any version available");
         context_attribs[0] = EGL_NONE;
-        egl_ctx->egl.ctx = eglCreateContext(egl_ctx->egl.dpy,
-                                            egl_ctx->egl.conf,
-                                            EGL_NO_CONTEXT,
-                                            context_attribs);
+        wl->egl_context.egl.ctx = eglCreateContext(wl->egl_context.egl.dpy,
+                                                   wl->egl_context.egl.conf,
+                                                   EGL_NO_CONTEXT,
+                                                   context_attribs);
 
-        if (!egl_ctx->egl.ctx)
+        if (!wl->egl_context.egl.ctx)
             return false;
     }
 
-    eglMakeCurrent(egl_ctx->egl.dpy, NULL, NULL, egl_ctx->egl.ctx);
+    eglMakeCurrent(wl->egl_context.egl.dpy, NULL, NULL, wl->egl_context.egl.ctx);
 
-    eglstr = eglQueryString(egl_ctx->egl.dpy, EGL_EXTENSIONS);
+    eglstr = eglQueryString(wl->egl_context.egl.dpy, EGL_EXTENSIONS);
 
     mpgl_load_functions(gl, (void*(*)(const GLubyte*))eglGetProcAddress, eglstr,
                         wl->log);
@@ -146,23 +128,22 @@ static bool egl_create_context(struct vo_wayland_state *wl,
 }
 
 static void egl_create_window(struct vo_wayland_state *wl,
-                              struct egl_context *egl_ctx,
                               uint32_t width,
                               uint32_t height)
 {
-    egl_ctx->egl_window = wl_egl_window_create(wl->window.surface,
-                                               wl->window.width,
-                                               wl->window.height);
+    wl->egl_context.egl_window = wl_egl_window_create(wl->window.surface,
+                                                      wl->window.width,
+                                                      wl->window.height);
 
-    egl_ctx->egl_surface = eglCreateWindowSurface(egl_ctx->egl.dpy,
-                                                  egl_ctx->egl.conf,
-                                                  egl_ctx->egl_window,
-                                                  NULL);
+    wl->egl_context.egl_surface = eglCreateWindowSurface(wl->egl_context.egl.dpy,
+                                                         wl->egl_context.egl.conf,
+                                                         wl->egl_context.egl_window,
+                                                         NULL);
 
-    eglMakeCurrent(egl_ctx->egl.dpy,
-                   egl_ctx->egl_surface,
-                   egl_ctx->egl_surface,
-                   egl_ctx->egl.ctx);
+    eglMakeCurrent(wl->egl_context.egl.dpy,
+                   wl->egl_context.egl_surface,
+                   wl->egl_context.egl_surface,
+                   wl->egl_context.egl.ctx);
 
     wl_display_dispatch_pending(wl->display.display);
 }
@@ -172,7 +153,6 @@ static bool config_window_wayland(struct MPGLContext *ctx,
                                   uint32_t d_height,
                                   uint32_t flags)
 {
-    struct egl_context * egl_ctx = ctx->priv;
     struct vo_wayland_state * wl = ctx->vo->wayland;
     bool enable_alpha = !!(flags & VOFLAG_ALPHA);
     bool ret = false;
@@ -180,23 +160,23 @@ static bool config_window_wayland(struct MPGLContext *ctx,
     if (!vo_wayland_config(ctx->vo, d_width, d_height, flags))
         return false;
 
-    if (!egl_ctx->egl.ctx) {
+    if (!wl->egl_context.egl.ctx) {
         /* Create OpenGL context */
-        ret = egl_create_context(wl, egl_ctx, ctx, enable_alpha);
+        ret = egl_create_context(wl, ctx, enable_alpha);
 
         /* If successfully created the context and we don't want to hide the
          * window than also create the window immediately */
         if (ret && !(VOFLAG_HIDDEN & flags))
-            egl_create_window(wl, egl_ctx, d_width, d_height);
+            egl_create_window(wl, d_width, d_height);
 
         return ret;
     }
     else {
-        if (!egl_ctx->egl_window) {
+        if (!wl->egl_context.egl_window) {
             /* If the context exists and the hidden flag is unset then
              * create the window */
             if (!(VOFLAG_HIDDEN & flags))
-                egl_create_window(wl, egl_ctx, d_width, d_height);
+                egl_create_window(wl, d_width, d_height);
         }
         return true;
     }
@@ -205,35 +185,41 @@ static bool config_window_wayland(struct MPGLContext *ctx,
 static void releaseGlContext_wayland(MPGLContext *ctx)
 {
     GL *gl = ctx->gl;
-    struct egl_context * egl_ctx = ctx->priv;
+    struct vo_wayland_state *wl = ctx->vo->wayland;
 
     gl->Finish();
-    eglMakeCurrent(egl_ctx->egl.dpy, NULL, NULL, EGL_NO_CONTEXT);
-    eglDestroyContext(egl_ctx->egl.dpy, egl_ctx->egl.ctx);
-    eglTerminate(egl_ctx->egl.dpy);
+    eglMakeCurrent(wl->egl_context.egl.dpy, NULL, NULL, EGL_NO_CONTEXT);
+    eglDestroyContext(wl->egl_context.egl.dpy, wl->egl_context.egl.ctx);
+    eglTerminate(wl->egl_context.egl.dpy);
     eglReleaseThread();
-    wl_egl_window_destroy(egl_ctx->egl_window);
-    egl_ctx->egl.ctx = NULL;
+    wl_egl_window_destroy(wl->egl_context.egl_window);
+    wl->egl_context.egl.ctx = NULL;
 }
 
 static void swapGlBuffers_wayland(MPGLContext *ctx)
 {
-    struct egl_context * egl_ctx = ctx->priv;
     struct vo_wayland_state *wl = ctx->vo->wayland;
+    eglSwapBuffers(wl->egl_context.egl.dpy, wl->egl_context.egl_surface);
+}
+
+static int control(struct vo *vo, int *events, int request, void *data)
+{
+    struct vo_wayland_state *wl = vo->wayland;
+    int r = vo_wayland_control(vo, events, request, data);
 
-    eglSwapBuffers(egl_ctx->egl.dpy, egl_ctx->egl_surface);
+    // NOTE: VO_EVENT_EXPOSE is never returned by the wayland backend
+    if (*events & VO_EVENT_RESIZE)
+        egl_resize(wl);
 
-    if (wl->window.events & VO_EVENT_RESIZE)
-        egl_resize(wl, egl_ctx);
+    return r;
 }
 
 void mpgl_set_backend_wayland(MPGLContext *ctx)
 {
-    ctx->priv = talloc_zero(ctx, struct egl_context);
     ctx->config_window = config_window_wayland;
     ctx->releaseGlContext = releaseGlContext_wayland;
     ctx->swapGlBuffers = swapGlBuffers_wayland;
-    ctx->vo_control = vo_wayland_control;
+    ctx->vo_control = control;
     ctx->vo_init = vo_wayland_init;
     ctx->vo_uninit = vo_wayland_uninit;
 }
diff --git a/video/out/wayland_common.h b/video/out/wayland_common.h
index 01ff09fa43..ac5fc3cf39 100644
--- a/video/out/wayland_common.h
+++ b/video/out/wayland_common.h
@@ -27,6 +27,12 @@
 
 #include "config.h"
 
+#if HAVE_GL_WAYLAND
+#include <wayland-egl.h>
+#include <EGL/egl.h>
+#include <EGL/eglext.h>
+#endif
+
 struct vo;
 
 struct vo_wayland_output {
@@ -43,6 +49,20 @@ struct vo_wayland_state {
     struct vo *vo;
     struct mp_log* log;
 
+#if HAVE_GL_WAYLAND
+    struct {
+        EGLSurface egl_surface;
+
+        struct wl_egl_window *egl_window;
+
+        struct {
+            EGLDisplay dpy;
+            EGLContext ctx;
+            EGLConfig conf;
+        } egl;
+    } egl_context;
+#endif
+
     struct {
         int fd;
         struct wl_display *display;