Create window matching GL fb configmaster

Even when we specify the X visual ID as input to glXChooseFBConfig, we
can get a FB config that requires a different visual, so make sure to
create the X window matching the selected FB config's visual.

1 files changed, 36 insertions, 3 deletions

diff --git a/main.c b/main.c
index a66229b..b7714c1 100644
--- a/main.c
+++ b/main.c
@@ -592,14 +592,47 @@ main(int argc, char **argv)
     Cursor cursor;
     XColor dummy = { 0 };
     Atom state;
+    int visual_id;
     const char *extensions;
+    XVisualInfo visual_template;
+    XVisualInfo *visual_info;
+    int n_visual_info;
 
-    /* Initialize X and create our window */
+    /* Initialize X */
 
     display = XOpenDisplay(NULL);
     screen = DefaultScreen(display);
     root_window = DefaultRootWindow(display);
 
+    /* Initialize GL */
+
+    if (!glXQueryExtension(display, &glx_error_base, &glx_event_base))
+        error("No GLX!");
+
+    i = 0;
+    attributes[i++] = GLX_VISUAL_ID;
+    attributes[i++] = DefaultVisual(display, screen)->visualid;
+    attributes[i++] = GLX_DOUBLEBUFFER;
+    attributes[i++] = True; 
+    attributes[i++] = None;
+
+    g_assert(i == G_N_ELEMENTS(attributes));
+
+    config = glXChooseFBConfig(display, screen, attributes, &n_configs);
+    if(!config)
+        error("Couldn't find FBConfig");
+
+    glXGetFBConfigAttrib (display, *config,
+                          GLX_VISUAL_ID, &visual_id );
+    visual_template.visualid = visual_id;
+    visual_info = XGetVisualInfo (display, VisualIDMask,
+                                  &visual_template, &n_visual_info);
+
+    /* Create our window */
+
+    attrs.colormap = XCreateColormap(display, root_window, visual_info[0].visual, AllocNone);
+    attrs_mask |= CWColormap;
+
     attrs.event_mask = ExposureMask | StructureNotifyMask | ButtonPressMask | ButtonReleaseMask | KeyPressMask;
     attrs_mask |= CWEventMask;
 
@@ -620,8 +653,8 @@ main(int argc, char **argv)
                            (DisplayWidth(display, screen) - WIDTH) / 2,
                            (DisplayHeight(display, screen) - HEIGHT) / 2,
                            WIDTH, HEIGHT,
-                           0, CopyFromParent,
-                           InputOutput, CopyFromParent,
+                           0, visual_info[0].depth,
+                           InputOutput, visual_info[0].visual,
                            attrs_mask, &attrs);
     window_width = WIDTH;
     window_height = HEIGHT;