apprt: plumb through scroll mods to core, don't handle them yet

src/Surface.zig

@@ -1268,7 +1268,14 @@ pub fn refreshCallback(self: *Surface) !void {
     try self.queueRender();
 }
 
-pub fn scrollCallback(self: *Surface, xoff: f64, yoff: f64) !void {
+pub fn scrollCallback(
+    self: *Surface,
+    xoff: f64,
+    yoff: f64,
+    scroll_mods: input.ScrollMods,
+) !void {
+    _ = scroll_mods;
+
     const tracy = trace(@src());
     defer tracy.end();
 

src/apprt/embedded.zig

@@ -299,8 +299,13 @@ pub const Surface = struct {
         };
     }
 
-    pub fn scrollCallback(self: *Surface, xoff: f64, yoff: f64) void {
+    pub fn scrollCallback(
-        self.core_surface.scrollCallback(xoff, yoff) catch |err| {
+        self: *Surface,
+        xoff: f64,
+        yoff: f64,
+        mods: input.ScrollMods,
+    ) void {
+        self.core_surface.scrollCallback(xoff, yoff, mods) catch |err| {
             log.err("error in scroll callback err={}", .{err});
             return;
         };
@@ -508,8 +513,11 @@ pub const CAPI = struct {
         y: f64,
         scroll_mods: c_int,
     ) void {
-        _ = scroll_mods;
+        surface.scrollCallback(
-        surface.scrollCallback(x, y);
+            x,
+            y,
+            @bitCast(input.ScrollMods, @truncate(u8, @bitCast(c_uint, scroll_mods))),
+        );
     }
 
     export fn ghostty_surface_ime_point(surface: *Surface, x: *f64, y: *f64) void {

src/apprt/glfw.zig

@@ -731,8 +731,11 @@ pub const Surface = struct {
         const tracy = trace(@src());
         defer tracy.end();
 
+        // Glfw doesn't support any of the scroll mods.
+        const scroll_mods: input.ScrollMods = .{};
+
         const core_win = window.getUserPointer(CoreSurface) orelse return;
-        core_win.scrollCallback(xoff, yoff) catch |err| {
+        core_win.scrollCallback(xoff, yoff, scroll_mods) catch |err| {
             log.err("error in scroll callback err={}", .{err});
             return;
         };

src/apprt/gtk.zig

@@ -1049,7 +1049,11 @@ pub const Surface = struct {
         ud: ?*anyopaque,
     ) callconv(.C) void {
         const self = userdataSelf(ud.?);
-        self.core_surface.scrollCallback(x, y * -1) catch |err| {
+
+        // GTK doesn't support any of the scroll mods.
+        const scroll_mods: input.ScrollMods = .{};
+
+        self.core_surface.scrollCallback(x, y * -1, scroll_mods) catch |err| {
             log.err("error in scroll callback err={}", .{err});
             return;
         };