From e16b46302bffd5d236981f657f195cf2b02ca172 Mon Sep 17 00:00:00 2001
From: "Michael D. Lowis" <mike@mdlowis.com>
Date: Sun, 30 Apr 2017 14:12:51 -0400
Subject: [PATCH] Optimize motion events by allowing the server to skip
 intermediate move events. Also potentially fixed an issue with selection
 callbacks not happening promptly when we own the selection. More testing
 required for that

---
 lib/x11.c | 33 +++++++++++++++++++++++----------
 1 file changed, 23 insertions(+), 10 deletions(-)

diff --git a/lib/x11.c b/lib/x11.c
index cdf49e2..42bf479 100644
--- a/lib/x11.c
+++ b/lib/x11.c
@@ -140,6 +140,7 @@ void x11_window(char* name, int width, int height) {
         | ButtonReleaseMask
         | ButtonMotionMask
         | PointerMotionMask
+        | PointerMotionHintMask
         | KeyPressMask
         | ExposureMask
         | FocusChangeMask);
@@ -328,16 +329,24 @@ void x11_handle_events(void) {
 void x11_loop(void) {
     fd_set fds;
     int xfd = ConnectionNumber(X.display);
+    Window xw;
+    unsigned int ux;
+    int winx, winy, x;
+    
     for (XEvent e; Running;) {
         struct timeval tv = { .tv_usec = 100000 };
         FD_ZERO(&fds);
         FD_SET(xfd, &fds);
-    
-        int ready = select(xfd+1, &fds, NULL, NULL, &tv);
-        if (ready > 0)
+        
+        /* wait for activity on the socket. if we tiemd out, query for the 
+           pointer position so we can track the mouse focus without flooding the 
+           event queue with motion events */
+        int ready = select(xfd+1, &fds, NULL, NULL, &tv); 
+        if (ready > 0) {
             x11_handle_events();
-        //else
-        //    timer expired
+        } else {
+            XQueryPointer(X.display, X.window, &xw, &xw, &x, &x, &winx, &winy, &ux);
+        }
         
         if (Running) {
             /* redraw the window */
@@ -590,16 +599,20 @@ static void selrequest(XEvent* evnt) {
             (unsigned char*)sel->text, strlen(sel->text));
     }
     XSendEvent(X.display, s.xselection.requestor, True, 0, &s);
+    XFlush(X.display);
 }
 
 bool x11_getsel(int selid, void(*cbfn)(char*)) {
     struct XSel* sel = &(Selections[selid]);
     if (sel->callback) return false;
-    if (XGetSelectionOwner(X.display, sel->atom) == None) 
-        return true;
-    sel->callback = cbfn;    
-    XConvertSelection(X.display, sel->atom, SelTarget, sel->atom, X.window, CurrentTime);
-    XFlush(X.display);
+    Window owner = XGetSelectionOwner(X.display, sel->atom);
+    if (owner == X.window) {
+        cbfn(sel->text);
+    } else if (owner != None){
+        sel->callback = cbfn;    
+        XConvertSelection(X.display, sel->atom, SelTarget, sel->atom, X.window, CurrentTime);
+        XFlush(X.display);
+    }
     return true;
 }
 
-- 
2.52.0