Implement wheel scrolling

kitty/char_grid.py

@@ -228,7 +228,8 @@ class CharGrid:
             self.screen.mark_as_dirty()
 
     def scroll(self, amt, upwards=True):
-        amt = {'line': 1, 'page': self.screen.lines - 1, 'full': self.screen.historybuf.count}[amt]
+        if not isinstance(amt, int):
+            amt = {'line': 1, 'page': self.screen.lines - 1, 'full': self.screen.historybuf.count}[amt]
         if not upwards:
             amt *= -1
         y = max(0, min(self.scrolled_by + amt, self.screen.historybuf.count))

kitty/config.py

@@ -45,6 +45,7 @@ type_map = {
     'cursor_opacity': to_opacity,
     'repaint_delay': int,
     'window_border_width': float,
+    'wheel_scroll_multiplier': float,
 }
 
 for name in 'foreground background cursor active_border_color inactive_border_color selection_foreground selection_background'.split():

kitty/kitty.conf

@@ -30,6 +30,9 @@ font_size        11.0
 # Number of lines of history to keep in memory for scrolling back
 scrollback_lines 2000
 
+# Wheel scroll multiplier (modify the amount scrolled by the mouse wheel)
+wheel_scroll_multiplier 5.0
+
 # Delay (in milliseconds) between screen updates. Decreasing it, increases fps
 # at the cost of more CPU usage. The default value yields ~50fps which is more
 # that sufficient for most uses.

kitty/tabs.py

@@ -332,12 +332,12 @@ class TabManager(Thread):
     def on_mouse_move(self, window, xpos, ypos):
         w = self.window_for_pos(*glfw.glfwGetCursorPos(window))
         if w is not None:
-            w.on_mouse_move(xpos, ypos)
+            w.on_mouse_move(window, xpos, ypos)
 
     def on_mouse_scroll(self, window, x, y):
         w = self.window_for_pos(*glfw.glfwGetCursorPos(window))
         if w is not None:
-            w.on_mouse_scroll(x, y)
+            w.on_mouse_scroll(window, x, y)
 
     # GUI thread API {{{
     def render(self):

kitty/window.py

@@ -10,7 +10,7 @@ from functools import partial
 import glfw
 import glfw_constants
 from .char_grid import CharGrid
-from .constants import wakeup, tab_manager, appname, WindowGeometry, queue_action
+from .constants import wakeup, tab_manager, appname, WindowGeometry
 from .fast_data_types import (
     BRACKETED_PASTE_START, BRACKETED_PASTE_END, Screen, read_bytes_dump, read_bytes
 )
@@ -124,12 +124,20 @@ class Window:
                 self.paste_from_selection()
                 return
 
-    def on_mouse_move(self, x, y):
+    def on_mouse_move(self, window, x, y):
         if self.char_grid.current_selection.in_progress:
             self.char_grid.update_drag(None, max(0, x - self.geometry.left), max(0, y - self.geometry.top))
 
-    def on_mouse_scroll(self, x, y):
-        pass
+    def on_mouse_scroll(self, window, x, y):
+        ignore_mouse_mode = (
+            glfw.glfwGetKey(window, glfw_constants.GLFW_KEY_LEFT_SHIFT) == glfw_constants.GLFW_PRESS or
+            glfw.glfwGetKey(window, glfw_constants.GLFW_KEY_RIGHT_SHIFT) == glfw_constants.GLFW_PRESS or
+            not self.screen.mouse_button_tracking_enabled())
+        if ignore_mouse_mode:
+            s = int(round(y * self.opts.wheel_scroll_multiplier))
+            if abs(s) > 0:
+                self.char_grid.scroll(abs(s), s > 0)
+                glfw.glfwPostEmptyEvent()
 
     # actions {{{
 
@@ -150,22 +158,28 @@ class Window:
         self.paste(text)
 
     def scroll_line_up(self):
-        queue_action(self.char_grid.scroll, 'line', True)
+        self.char_grid.scroll('line', True)
+        glfw.glfwPostEmptyEvent()
 
     def scroll_line_down(self):
-        queue_action(self.char_grid.scroll, 'line', False)
+        self.char_grid.scroll('line', False)
+        glfw.glfwPostEmptyEvent()
 
     def scroll_page_up(self):
-        queue_action(self.char_grid.scroll, 'page', True)
+        self.char_grid.scroll('page', True)
+        glfw.glfwPostEmptyEvent()
 
     def scroll_page_down(self):
-        queue_action(self.char_grid.scroll, 'page', False)
+        self.char_grid.scroll('page', False)
+        glfw.glfwPostEmptyEvent()
 
     def scroll_home(self):
-        queue_action(self.char_grid.scroll, 'full', True)
+        self.char_grid.scroll('full', True)
+        glfw.glfwPostEmptyEvent()
 
     def scroll_end(self):
-        queue_action(self.char_grid.scroll, 'full', False)
+        self.char_grid.scroll('full', False)
+        glfw.glfwPostEmptyEvent()
     # }}}
 
     def dump_commands(self, *a):