add ability to set parent window when creating windows

Author: Mike Blumenkrantz

src/lib.rs

@@ -57,7 +57,7 @@ pub use events::*;
 #[cfg(feature = "headless")]
 pub use headless::{HeadlessRendererBuilder, HeadlessContext};
 #[cfg(feature = "window")]
-pub use window::{WindowBuilder, Window, WindowProxy, PollEventsIterator, WaitEventsIterator};
+pub use window::{WindowBuilder, Window, WindowID, WindowProxy, PollEventsIterator, WaitEventsIterator};
 #[cfg(feature = "window")]
 pub use window::{AvailableMonitorsIter, MonitorID, get_available_monitors, get_primary_monitor};
 #[cfg(feature = "window")]
@@ -260,6 +260,7 @@ pub struct BuilderAttribs<'a> {
     alpha_bits: Option<u8>,
     stereoscopy: bool,
     srgb: Option<bool>,
+    parent: *mut libc::c_void,
 }
 
 impl BuilderAttribs<'static> {
@@ -282,6 +283,7 @@ impl BuilderAttribs<'static> {
             alpha_bits: None,
             stereoscopy: false,
             srgb: None,
+            parent: std::ptr::null_mut(),
         }
     }
 }
@@ -308,6 +310,7 @@ impl<'a> BuilderAttribs<'a> {
             alpha_bits: self.alpha_bits,
             stereoscopy: self.stereoscopy,
             srgb: self.srgb,
+            parent: self.parent,
         };
 
         (new_attribs, sharing)

src/window.rs

@@ -129,6 +129,12 @@ impl<'a> WindowBuilder<'a> {
         self
     }
 
+    /// Sets the parent window
+    pub fn with_parent(mut self, parent: WindowID) -> WindowBuilder<'a> {
+        self.attribs.parent = parent;
+        self
+    }
+
     /// Builds the window.
     ///
     /// Error should be very rare and only occur in case of permission denied, incompatible system,
@@ -528,3 +534,7 @@ impl MonitorID {
         id.get_dimensions()
     }
 }
+
+
+/// Identifier for a display system window.
+pub type WindowID = *mut libc::c_void;

src/x11/window/mod.rs

@@ -414,21 +414,17 @@ impl Window {
             }
         };
 
-        // getting the root window
-        let root = unsafe { ffi::XDefaultRootWindow(display) };
-
-        // creating the color map
-        let cmap = unsafe {
-            let cmap = ffi::XCreateColormap(display, root,
-                visual_infos.visual as *mut _, ffi::AllocNone);
-            // TODO: error checking?
-            cmap
+        // getting the parent window
+        let parent = if builder.parent.is_null() {
+                         unsafe { ffi::XDefaultRootWindow(display) }
+        } else {
+            builder.parent as ffi::Window
         };
 
         // creating
         let mut set_win_attr = {
             let mut swa: ffi::XSetWindowAttributes = unsafe { mem::zeroed() };
-            swa.colormap = cmap;
+            swa.colormap = 0;
             swa.event_mask = ffi::ExposureMask | ffi::StructureNotifyMask |
                 ffi::VisibilityChangeMask | ffi::KeyPressMask | ffi::PointerMotionMask |
                 ffi::KeyReleaseMask | ffi::ButtonPressMask |
@@ -450,7 +446,7 @@ impl Window {
 
         // finally creating the window
         let window = unsafe {
-            let win = ffi::XCreateWindow(display, root, 0, 0, dimensions.0 as libc::c_uint,
+            let win = ffi::XCreateWindow(display, parent, 0, 0, dimensions.0 as libc::c_uint,
                 dimensions.1 as libc::c_uint, 0, visual_infos.depth, ffi::InputOutput as libc::c_uint,
                 visual_infos.visual as *mut _, window_attributes,
                 &mut set_win_attr);