Creating subwindow fails with BadRegion? - rust

Question

In trying to fix https://stackoverflow.com/a/69647995?noredirect=1, I had an idea; what if I drew the things (that were failing to draw directly on the window) in subwindows of the frame window? It looks like other WMs like Openbox also took this approach.
So I tried doing this:
let text_win = self.conn.generate_id()?;
let text_win_aux = xproto::CreateWindowAux::new()
.event_mask(
xproto::EventMask::EXPOSURE
| xproto::EventMask::SUBSTRUCTURE_REDIRECT
| xproto::EventMask::SUBSTRUCTURE_NOTIFY
| xproto::EventMask::BUTTON_PRESS
| xproto::EventMask::BUTTON_RELEASE
| xproto::EventMask::POINTER_MOTION
| xproto::EventMask::ENTER_WINDOW
| xproto::EventMask::PROPERTY_CHANGE,
)
.background_pixel(0xFFFFFF);
self.conn.create_window(
COPY_DEPTH_FROM_PARENT,
text_win,
frame_win,
15,
15,
60,
25,
0,
xproto::WindowClass::INPUT_OUTPUT,
screen.root_visual,
&text_win_aux,
)?;
self.conn.map_window(text_win)?
But it doesn't work (there is no white rectangle rendered), and it looks like I get a BadRegion error too.
What I expect is that a white rectangle is rendered on the frame window (as the background_pixel of the child is white, and I map it to the frame).
What could I be doing wrong? This doesn't seem to be affected by depth, btw.

Answer 1

I've figured it out. The "text_win" needs to be using the same visual as the frame window; I accidentally used the X11 screen's root visual instead.
So this create_window call functions as expected:
.background_pixel(0xFFFFFF);
self.conn.create_window(
COPY_DEPTH_FROM_PARENT,
text_win,
frame_win,
15,
15,
60,
25,
0,
xproto::WindowClass::INPUT_OUTPUT,
attr.visual,
&text_win_aux,
)?;
(Also, I discovered that the BadRegion was something else, it was a xcompmgr bug, nothing related to this)