From 9fd8dd9cec44d99bd7c4e7be5ccb40ae6e04862e Mon Sep 17 00:00:00 2001
From: Victor Brekenfeld <github@drakulix.de>
Date: Sun, 7 Jun 2020 23:11:27 +0200
Subject: [PATCH] anvil: allow draw_windows to take optional output coordinates

---
 anvil/src/glium_drawer.rs | 10 +++++++++-
 anvil/src/udev.rs         |  7 ++++++-
 anvil/src/window_map.rs   |  4 ++--
 anvil/src/winit.rs        |  2 +-
 src/utils/rectangle.rs    | 16 ++++++++++++++++
 5 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/anvil/src/glium_drawer.rs b/anvil/src/glium_drawer.rs
index 49b7301..273502c 100644
--- a/anvil/src/glium_drawer.rs
+++ b/anvil/src/glium_drawer.rs
@@ -26,6 +26,7 @@ use smithay::{
         calloop::LoopHandle,
         wayland_server::protocol::{wl_buffer, wl_surface},
     },
+    utils::Rectangle,
     wayland::{
         compositor::{roles::Role, SubsurfaceRole, TraversalAction},
         data_device::DnDIconRole,
@@ -403,12 +404,19 @@ impl<F: GLGraphicsBackend + 'static> GliumDrawer<F> {
         &self,
         frame: &mut Frame,
         window_map: &MyWindowMap,
+        output_rect: Option<Rectangle>,
         compositor_token: MyCompositorToken,
     ) {
         // redraw the frame, in a simple but inneficient way
         {
             let screen_dimensions = self.borrow().get_framebuffer_dimensions();
-            window_map.with_windows_from_bottom_to_top(|toplevel_surface, initial_place| {
+            window_map.with_windows_from_bottom_to_top(|toplevel_surface, initial_place, bounding_box| {
+                // skip windows that do not overlap with a given output
+                if let Some(output) = output_rect {
+                    if !output.overlaps(bounding_box) {
+                        return;
+                    }
+                }
                 if let Some(wl_surface) = toplevel_surface.get_surface() {
                     // this surface is a root of a subsurface tree that needs to be drawn
                     self.draw_surface_tree(
diff --git a/anvil/src/udev.rs b/anvil/src/udev.rs
index dad9b04..01007a5 100644
--- a/anvil/src/udev.rs
+++ b/anvil/src/udev.rs
@@ -601,7 +601,12 @@ impl DrmRenderer {
             let mut frame = drawer.draw();
             frame.clear(None, Some((0.8, 0.8, 0.9, 1.0)), false, Some(1.0), None);
             // draw the surfaces
-            drawer.draw_windows(&mut frame, &*self.window_map.borrow(), self.compositor_token);
+            drawer.draw_windows(
+                &mut frame,
+                &*self.window_map.borrow(),
+                None,
+                self.compositor_token,
+            );
             let (x, y) = *self.pointer_location.borrow();
             // draw the dnd icon if applicable
             {
diff --git a/anvil/src/window_map.rs b/anvil/src/window_map.rs
index fdfdc19..9eeec69 100644
--- a/anvil/src/window_map.rs
+++ b/anvil/src/window_map.rs
@@ -248,10 +248,10 @@ where
 
     pub fn with_windows_from_bottom_to_top<Func>(&self, mut f: Func)
     where
-        Func: FnMut(&Kind<R>, (i32, i32)),
+        Func: FnMut(&Kind<R>, (i32, i32), &Rectangle),
     {
         for w in self.windows.iter().rev() {
-            f(&w.toplevel, w.location)
+            f(&w.toplevel, w.location, &w.bbox)
         }
     }
 
diff --git a/anvil/src/winit.rs b/anvil/src/winit.rs
index bd2d549..0e0f221 100644
--- a/anvil/src/winit.rs
+++ b/anvil/src/winit.rs
@@ -103,7 +103,7 @@ pub fn run_winit(
             frame.clear(None, Some((0.8, 0.8, 0.9, 1.0)), false, Some(1.0), None);
 
             // draw the windows
-            drawer.draw_windows(&mut frame, &*state.window_map.borrow(), state.ctoken);
+            drawer.draw_windows(&mut frame, &*state.window_map.borrow(), None, state.ctoken);
 
             let (x, y) = *state.pointer_location.borrow();
             // draw the dnd icon if any
diff --git a/src/utils/rectangle.rs b/src/utils/rectangle.rs
index 5cd8357..575c565 100644
--- a/src/utils/rectangle.rs
+++ b/src/utils/rectangle.rs
@@ -17,4 +17,20 @@ impl Rectangle {
         let (x, y) = point;
         (x >= self.x) && (x < self.x + self.width) && (y >= self.y) && (y < self.y + self.height)
     }
+
+    /// Checks whether a given rectangle overlaps with this one
+    pub fn overlaps(&self, other: &Rectangle) -> bool {
+        // if the rectangle is not outside of the other
+        // they must overlap
+        !(
+            // self is left of other
+            self.x + self.width < other.x
+            // self is right of other
+            ||  self.x > other.x + other.width
+            // self is above of other
+            ||  self.y + self.height < other.y
+            // self is below of other
+            ||  self.y > other.y + other.height
+        )
+    }
 }