Move the scroll event handler to C

kitty/glfw.c

@@ -36,7 +36,7 @@ typedef struct {
     PyObject_HEAD
 
     GLFWwindow *window;
-    PyObject *framebuffer_size_callback, *char_mods_callback, *key_callback, *mouse_button_callback, *scroll_callback, *cursor_pos_callback, *window_focus_callback;
+    PyObject *framebuffer_size_callback, *char_mods_callback, *key_callback, *window_focus_callback;
     GLFWcursor *standard_cursor, *click_cursor, *arrow_cursor;
 } WindowWrapper;
 
@@ -68,6 +68,7 @@ key_callback(GLFWwindow UNUSED *w, int key, int scancode, int action, int mods)
 }
 
 extern void mouse_event(int, int);
+extern void scroll_event(double, double);
 
 static void 
 mouse_button_callback(GLFWwindow *w, int button, int action, int mods) {
@@ -78,7 +79,6 @@ mouse_button_callback(GLFWwindow *w, int button, int action, int mods) {
         global_state.mouse_button_pressed[button] = action == GLFW_PRESS ? true : false;
         mouse_event(button, mods);
     }
-    /* WINDOW_CALLBACK(mouse_button_callback, "iii", button, action, mods); */
 }
 
 static void 
@@ -89,7 +89,6 @@ cursor_pos_callback(GLFWwindow *w, double x, double y) {
     global_state.cursor_blink_zero_time = now;
     global_state.mouse_x = x; global_state.mouse_y = y;
     mouse_event(-1, 0);
-    /* WINDOW_CALLBACK(cursor_pos_callback, "dd", x, y); */
 }
 
 static void 
@@ -97,7 +96,7 @@ scroll_callback(GLFWwindow *w, double xoffset, double yoffset) {
     if (!global_state.mouse_visible) { glfwSetInputMode(w, GLFW_CURSOR, GLFW_CURSOR_NORMAL); global_state.mouse_visible = true; } 
     double now = monotonic();
     global_state.last_mouse_activity_at = now;
-    WINDOW_CALLBACK(scroll_callback, "dd", xoffset, yoffset);
+    scroll_event(xoffset, yoffset);
 }
 
 static void 
@@ -147,10 +146,10 @@ new(PyTypeObject *type, PyObject *args, PyObject UNUSED *kwds) {
         set_mouse_cursor(0);
         glfwSetFramebufferSizeCallback(self->window, framebuffer_size_callback);
         glfwSetCharModsCallback(self->window, char_mods_callback);
-        glfwSetKeyCallback(self->window, key_callback);
         glfwSetMouseButtonCallback(self->window, mouse_button_callback);
         glfwSetScrollCallback(self->window, scroll_callback);
         glfwSetCursorPosCallback(self->window, cursor_pos_callback);
+        glfwSetKeyCallback(self->window, key_callback);
         glfwSetWindowFocusCallback(self->window, window_focus_callback);
     }
     return (PyObject*)self;
@@ -263,7 +262,7 @@ glfw_init_hint_string(PyObject UNUSED *self, PyObject *args) {
 static void
 dealloc(WindowWrapper* self) {
     the_window = NULL;
-    Py_CLEAR(self->framebuffer_size_callback); Py_CLEAR(self->char_mods_callback); Py_CLEAR(self->key_callback); Py_CLEAR(self->mouse_button_callback); Py_CLEAR(self->scroll_callback); Py_CLEAR(self->cursor_pos_callback); Py_CLEAR(self->window_focus_callback);
+    Py_CLEAR(self->framebuffer_size_callback); Py_CLEAR(self->char_mods_callback); Py_CLEAR(self->key_callback); Py_CLEAR(self->window_focus_callback);
     if (self->window != NULL) glfwDestroyWindow(self->window);
     Py_TYPE(self)->tp_free((PyObject*)self);
 }
@@ -452,9 +451,6 @@ static PyMemberDef members[] = {
     CBE(framebuffer_size_callback),
     CBE(char_mods_callback),
     CBE(key_callback),
-    CBE(mouse_button_callback),
-    CBE(scroll_callback),
-    CBE(cursor_pos_callback),
     CBE(window_focus_callback),
     {NULL}
 #undef CBE

kitty/mouse.c

@@ -8,6 +8,7 @@
 #include "state.h"
 #include "screen.h"
 #include "lineops.h"
+#include <math.h>
 #include <GLFW/glfw3.h>
 
 extern void set_mouse_cursor(MouseShape);
@@ -203,23 +204,56 @@ handle_tab_bar_mouse(int button, int UNUSED modifiers) {
     call_boss(activate_tab_at, "d", global_state.mouse_x);
 }
 
-void
-mouse_event(int button, int modifiers) {
-    MouseShape old_cursor = mouse_cursor_shape;
-    bool in_tab_bar = global_state.num_tabs > 1 && global_state.mouse_y >= global_state.viewport_height - global_state.cell_height ? true : false;
-    if (in_tab_bar) { 
-        mouse_cursor_shape = HAND;
-        handle_tab_bar_mouse(button, modifiers); 
-    } else {
+static inline Window*
+window_for_event(unsigned int *window_idx, bool *in_tab_bar) {
+    *in_tab_bar = global_state.num_tabs > 1 && global_state.mouse_y >= global_state.viewport_height - global_state.cell_height ? true : false;
+    if (!*in_tab_bar) {
         Tab *t = global_state.tabs + global_state.active_tab;
         for (unsigned int i = 0; i < t->num_windows; i++) {
             if (contains_mouse(t->windows + i) && t->windows[i].render_data.screen) {
-                handle_event(t->windows + i, button, modifiers, i);
-                break;
+                *window_idx = i; return t->windows + i;
             }
         }
     }
+    return NULL;
+
+}
+
+void
+mouse_event(int button, int modifiers) {
+    MouseShape old_cursor = mouse_cursor_shape;
+    bool in_tab_bar;
+    unsigned int window_idx;
+    Window *w = window_for_event(&window_idx, &in_tab_bar);
+    if (in_tab_bar) { 
+        mouse_cursor_shape = HAND;
+        handle_tab_bar_mouse(button, modifiers); 
+    } else if(w) {
+        handle_event(w, button, modifiers, window_idx);
+    }
     if (mouse_cursor_shape != old_cursor) {
         set_mouse_cursor(mouse_cursor_shape);
     }
 }
+
+void
+scroll_event(double UNUSED xoffset, double yoffset) {
+    int s = (int) round(yoffset * OPT(wheel_scroll_multiplier));
+    if (s == 0) return;
+    bool upwards = s > 0 ? true : false;
+    bool in_tab_bar;
+    unsigned int window_idx;
+    Window *w = window_for_event(&window_idx, &in_tab_bar);
+    if (w) {
+        Screen *screen = w->render_data.screen;
+        if (screen->linebuf == screen->main_linebuf) {
+            screen_history_scroll(screen, abs(s), upwards);
+        } else {
+            if (screen->modes.mouse_tracking_mode) {
+                // TODO: Implement this
+            } else {
+                // TODO: Implement this, writing a up arrow or down arrow key event to the child    
+            }
+        }
+    }
+}

kitty/state.c

@@ -127,6 +127,7 @@ PYWRAP1(set_options) {
     S(cursor_shape, PyLong_AsLong);
     S(cursor_opacity, PyFloat_AsDouble);
     S(mouse_hide_wait, PyFloat_AsDouble);
+    S(wheel_scroll_multiplier, PyFloat_AsDouble);
     S(open_url_modifiers, PyLong_AsUnsignedLong);
     S(click_interval, PyFloat_AsDouble);
     PyObject *chars = PyObject_GetAttrString(args, "select_by_word_characters");

kitty/state.h

@@ -10,7 +10,7 @@
 #define OPT(name) global_state.opts.name
 
 typedef struct {
-    double visual_bell_duration, cursor_blink_interval, cursor_stop_blinking_after, mouse_hide_wait, click_interval, cursor_opacity;
+    double visual_bell_duration, cursor_blink_interval, cursor_stop_blinking_after, mouse_hide_wait, click_interval, cursor_opacity, wheel_scroll_multiplier;
     bool enable_audio_bell;
     CursorShape cursor_shape;
     unsigned int open_url_modifiers;