scroll using middle-click + mouse-movement

caillou · Apr 10, 2020 · 21f268f · 21f268f
1 parent 5117526
commit 21f268f
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diff --git a/hammerspoon/init.lua b/hammerspoon/init.lua
@@ -38,6 +38,7 @@ require('keyboard.control-escape')
 -- require('keyboard.panes')
 require('keyboard.super')
 require('keyboard.windows')
+require('keyboard.scroll-with-trackpoint')
 
 hs.notify.new({
   title='Hammerspoon',

diff --git a/hammerspoon/scroll-with-trackpoint.lua b/hammerspoon/scroll-with-trackpoint.lua
@@ -0,0 +1,62 @@
+-- HANDLE SCROLLING WITH MOUSE BUTTON PRESSED
+local scrollMouseButton = 2
+local deferred = false
+
+-- Load the mouse extension before having go use it.
+-- If it is loaded on first use, the delay can lead to problems.
+hs.mouse.getAbsolutePosition()
+
+overrideOtherMouseDown = hs.eventtap.new({ hs.eventtap.event.types.otherMouseDown }, function(e)
+    -- print("down")
+    local pressedMouseButton = e:getProperty(hs.eventtap.event.properties['mouseEventButtonNumber'])
+    if scrollMouseButton == pressedMouseButton
+        then
+            deferred = true
+            return true
+        end
+end)
+
+overrideOtherMouseUp = hs.eventtap.new({ hs.eventtap.event.types.otherMouseUp }, function(e)
+    -- print("up")
+    local pressedMouseButton = e:getProperty(hs.eventtap.event.properties['mouseEventButtonNumber'])
+    if scrollMouseButton == pressedMouseButton
+        then
+            if (deferred) then
+                overrideOtherMouseDown:stop()
+                overrideOtherMouseUp:stop()
+                hs.eventtap.otherClick(e:location(), pressedMouseButton)
+                overrideOtherMouseDown:start()
+                overrideOtherMouseUp:start()
+                return true
+            end
+            return false
+        end
+        return false
+end)
+
+local oldmousepos = {}
+local scrollmult = -4   -- negative multiplier makes mouse work like traditional scrollwheel
+
+dragOtherToScroll = hs.eventtap.new({ hs.eventtap.event.types.otherMouseDragged }, function(e)
+    local pressedMouseButton = e:getProperty(hs.eventtap.event.properties['mouseEventButtonNumber'])
+    -- print ("pressed mouse " .. pressedMouseButton)
+    if scrollMouseButton == pressedMouseButton
+        then
+            -- print("scroll");
+            deferred = false
+            oldmousepos = hs.mouse.getAbsolutePosition()
+
+            local dx = e:getProperty(hs.eventtap.event.properties['mouseEventDeltaX'])
+            local dy = e:getProperty(hs.eventtap.event.properties['mouseEventDeltaY'])
+            local scroll = hs.eventtap.event.newScrollEvent({dx * scrollmult, dy * scrollmult},{},'pixel')
+            -- put the mouse back
+            hs.mouse.setAbsolutePosition(oldmousepos)
+            return true, {scroll}
+        else
+            return false, {}
+        end
+end)
+
+overrideOtherMouseDown:start()
+overrideOtherMouseUp:start()
+dragOtherToScroll:start()