macos: mouse scroll events

include/ghostty.h

@@ -231,6 +231,7 @@ void ghostty_surface_key(ghostty_surface_t, ghostty_input_action_e, ghostty_inpu
 void ghostty_surface_char(ghostty_surface_t, uint32_t);
 void ghostty_surface_mouse_button(ghostty_surface_t, ghostty_input_mouse_state_e, ghostty_input_mouse_button_e, ghostty_input_mods_e);
 void ghostty_surface_mouse_pos(ghostty_surface_t, double, double);
+void ghostty_surface_mouse_scroll(ghostty_surface_t, double, double);
 
 #ifdef __cplusplus
 }

macos/Sources/TerminalSurfaceView.swift

@@ -329,6 +329,19 @@ class TerminalSurfaceView_Real: NSView, NSTextInputClient, ObservableObject {
         self.mouseMoved(with: event)
     }
     
+    override func scrollWheel(with event: NSEvent) {
+        guard let surface = self.surface else { return }
+        
+        var x = event.scrollingDeltaX
+        var y = event.scrollingDeltaY
+        if event.hasPreciseScrollingDeltas {
+            x *= 0.1
+            y *= 0.1
+        }
+        
+        ghostty_surface_mouse_scroll(surface, x, y)
+    }
+
     override func keyDown(with event: NSEvent) {
         guard let surface = self.surface else { return }
         let key = Self.keycodes[event.keyCode] ?? GHOSTTY_KEY_INVALID

src/App.zig

@@ -458,4 +458,8 @@ pub const CAPI = struct {
     export fn ghostty_surface_mouse_pos(win: *Window, x: f64, y: f64) void {
         win.window.cursorPosCallback(x, y);
     }
+
+    export fn ghostty_surface_mouse_scroll(win: *Window, x: f64, y: f64) void {
+        win.window.scrollCallback(x, y);
+    }
 };

src/apprt/embedded.zig

@@ -175,6 +175,13 @@ pub const Window = struct {
         };
     }
 
+    pub fn scrollCallback(self: *const Window, xoff: f64, yoff: f64) void {
+        self.core_win.scrollCallback(xoff, yoff) catch |err| {
+            log.err("error in scroll callback err={}", .{err});
+            return;
+        };
+    }
+
     pub fn cursorPosCallback(self: *Window, x: f64, y: f64) void {
         // Convert our unscaled x/y to scaled.
         self.cursor_pos = self.core_win.window.cursorPosToPixels(.{