vo_opengl: x11: move RGBA visual test to x11_common.c

So that the EGL code can use it too.

Also print the actual FB config ID, instead of nonsense. (I _think_ once
in the past a certain GLX implementation just used numeric config IDs
casted to EGLConfig - or at least that would explain this nonsense.)

3 files changed, 25 insertions, 12 deletions

diff --git a/video/out/opengl/context_x11.c b/video/out/opengl/context_x11.c
index 48533fe701..c71e0b327a 100644
--- a/video/out/opengl/context_x11.c
+++ b/video/out/opengl/context_x11.c
@@ -160,17 +160,13 @@ static GLXFBConfig select_fb_config(struct vo *vo, const int *attribs, int flags
     if (flags & VOFLAG_ALPHA) {
         for (int n = 0; n < fbcount; n++) {
             XVisualInfo *v = glXGetVisualFromFBConfig(vo->x11->display, fbc[n]);
-            if (!v)
-                continue;
-            // This is a heuristic at best. Note that normal 8 bit Visuals use
-            // a depth of 24, even if the pixels are padded to 32 bit. If the
-            // depth is higher than 24, the remaining bits must be alpha.
-            // Note: vinfo->bits_per_rgb appears to be useless (is always 8).
-            unsigned long mask = v->depth == sizeof(unsigned long) * 8 ?
-                (unsigned long)-1 : (1UL << v->depth) - 1;
-            if (mask & ~(v->red_mask | v->green_mask | v->blue_mask)) {
-                fbconfig = fbc[n];
-                break;
+            if (v) {
+                bool is_rgba = vo_x11_is_rgba_visual(v);
+                XFree(v);
+                if (is_rgba) {
+                    fbconfig = fbc[n];
+                    break;
+                }
             }
         }
     }
@@ -235,7 +231,10 @@ static int glx_init(struct MPGLContext *ctx, int flags)
         MP_ERR(vo, "no GLX support present\n");
         goto uninit;
     }
-    MP_VERBOSE(vo, "GLX chose FB config with ID 0x%x\n", (int)(intptr_t)fbc);
+
+    int fbid = -1;
+    if (!glXGetFBConfigAttrib(vo->x11->display, fbc, GLX_FBCONFIG_ID, &fbid))
+        MP_VERBOSE(vo, "GLX chose FB config with ID 0x%x\n", fbid);
 
     glx_ctx->fbc = fbc;
     glx_ctx->vinfo = glXGetVisualFromFBConfig(vo->x11->display, fbc);
diff --git a/video/out/x11_common.c b/video/out/x11_common.c
index 46e68d6e71..d42eb70dde 100644
--- a/video/out/x11_common.c
+++ b/video/out/x11_common.c
@@ -2044,3 +2044,15 @@ bool vo_x11_screen_is_composited(struct vo *vo)
     Atom NET_WM_CM = XInternAtom(x11->display, buf, False);
     return XGetSelectionOwner(x11->display, NET_WM_CM) != None;
 }
+
+// Return whether the given visual has alpha (when compositing is used).
+bool vo_x11_is_rgba_visual(XVisualInfo *v)
+{
+    // This is a heuristic at best. Note that normal 8 bit Visuals use
+    // a depth of 24, even if the pixels are padded to 32 bit. If the
+    // depth is higher than 24, the remaining bits must be alpha.
+    // Note: vinfo->bits_per_rgb appears to be useless (is always 8).
+    unsigned long mask = v->depth == sizeof(unsigned long) * 8 ?
+        (unsigned long)-1 : (1UL << v->depth) - 1;
+    return mask & ~(v->red_mask | v->green_mask | v->blue_mask);
+}
diff --git a/video/out/x11_common.h b/video/out/x11_common.h
index de2a805efd..6c92fdb480 100644
--- a/video/out/x11_common.h
+++ b/video/out/x11_common.h
@@ -139,4 +139,6 @@ void vo_x11_wait_events(struct vo *vo, int64_t until_time_us);
 
 void vo_x11_silence_xlib(int dir);
 
+bool vo_x11_is_rgba_visual(XVisualInfo *v);
+
 #endif /* MPLAYER_X11_COMMON_H */