Merge pull request #735 from gpanders/resize-increments

macos: set window resizeIncrements when cell size changes

include/ghostty.h

@@ -337,6 +337,7 @@ typedef void (*ghostty_runtime_goto_tab_cb)(void *, int32_t);
 typedef void (*ghostty_runtime_toggle_fullscreen_cb)(void *, ghostty_non_native_fullscreen_e);
 typedef void (*ghostty_runtime_set_initial_window_size_cb)(void *, uint32_t, uint32_t);
 typedef void (*ghostty_runtime_render_inspector_cb)(void *);
+typedef void (*ghostty_runtime_set_cell_size_cb)(void *, uint32_t, uint32_t);
 
 typedef struct {
     void *userdata;
@@ -359,6 +360,7 @@ typedef struct {
     ghostty_runtime_toggle_fullscreen_cb toggle_fullscreen_cb;
     ghostty_runtime_set_initial_window_size_cb set_initial_window_size_cb;
     ghostty_runtime_render_inspector_cb render_inspector_cb;
+    ghostty_runtime_set_cell_size_cb set_cell_size_cb;
 } ghostty_runtime_config_s;
 
 //-------------------------------------------------------------------

macos/Ghostty.xcodeproj/project.pbxproj

@@ -38,7 +38,6 @@
 		A5CEAFFF29C2410700646FDA /* Backport.swift in Sources */ = {isa = PBXBuildFile; fileRef = A5CEAFFE29C2410700646FDA /* Backport.swift */; };
 		A5FEB3002ABB69450068369E /* main.swift in Sources */ = {isa = PBXBuildFile; fileRef = A5FEB2FF2ABB69450068369E /* main.swift */; };
 		A5FECBD729D1FC3900022361 /* PrimaryView.swift in Sources */ = {isa = PBXBuildFile; fileRef = A5FECBD629D1FC3900022361 /* PrimaryView.swift */; };
-		A5FECBD929D2010400022361 /* WindowAccessor.swift in Sources */ = {isa = PBXBuildFile; fileRef = A5FECBD829D2010400022361 /* WindowAccessor.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
@@ -76,7 +75,6 @@
 		A5D495A1299BEC7E00DD1313 /* GhosttyKit.xcframework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.xcframework; path = GhosttyKit.xcframework; sourceTree = "<group>"; };
 		A5FEB2FF2ABB69450068369E /* main.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = main.swift; sourceTree = "<group>"; };
 		A5FECBD629D1FC3900022361 /* PrimaryView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PrimaryView.swift; sourceTree = "<group>"; };
-		A5FECBD829D2010400022361 /* WindowAccessor.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WindowAccessor.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -120,7 +118,6 @@
 				A5CEAFFE29C2410700646FDA /* Backport.swift */,
 				8503D7C62A549C66006CFF3D /* FullScreenHandler.swift */,
 				A59FB5D02AE0DEA7009128F3 /* MetalView.swift */,
-				A5FECBD829D2010400022361 /* WindowAccessor.swift */,
 				A5CEAFDA29B8005900646FDA /* SplitView */,
 			);
 			path = Helpers;
@@ -313,7 +310,6 @@
 				A5CDF1932AAF9E0800513312 /* ConfigurationErrorsController.swift in Sources */,
 				A59FB5D12AE0DEA7009128F3 /* MetalView.swift in Sources */,
 				A55685E029A03A9F004303CE /* AppError.swift in Sources */,
-				A5FECBD929D2010400022361 /* WindowAccessor.swift in Sources */,
 				A535B9DA299C569B0017E2E4 /* ErrorView.swift in Sources */,
 				85102A1C2A6E32890084AB3E /* PrimaryWindowController.swift in Sources */,
 				A5CEAFFF29C2410700646FDA /* Backport.swift in Sources */,

macos/Sources/Features/Primary Window/PrimaryView.swift

@@ -14,9 +14,10 @@ struct PrimaryView: View {
     // If this is set, this is the base configuration that we build our surface out of.
     let baseConfig: Ghostty.SurfaceConfiguration?
     
-    // We need access to our window to know if we're the key window to determine
+    // We need access to our window to know if we're the key window and to
-    // if we show the quit confirmation or not.
+    // modify window properties in response to events from the surface (e.g.
-    @State private var window: NSWindow?
+    // updating the window title)
+    var window: NSWindow
     
     // This handles non-native fullscreen
     @State private var fullScreen = FullScreenHandler()
@@ -27,6 +28,7 @@ struct PrimaryView: View {
     @FocusedValue(\.ghosttySurfaceView) private var focusedSurface
     @FocusedValue(\.ghosttySurfaceTitle) private var surfaceTitle
     @FocusedValue(\.ghosttySurfaceZoomed) private var zoomedSplit
+    @FocusedValue(\.ghosttySurfaceCellSize) private var cellSize
     
     // The title for our window
     private var title: String {
@@ -68,7 +70,6 @@ struct PrimaryView: View {
                 Ghostty.TerminalSplit(onClose: Self.closeWindow, baseConfig: self.baseConfig)
                     .ghosttyApp(ghostty.app!)
                     .ghosttyConfig(ghostty.config!)
-                    .background(WindowAccessor(window: $window))
                     .onReceive(gotoTab) { onGotoTab(notification: $0) }
                     .onReceive(toggleFullscreen) { onToggleFullscreen(notification: $0) }
                     .focused($focused)
@@ -79,8 +80,12 @@ struct PrimaryView: View {
                     .onChange(of: title) { newValue in
                         // We need to handle this manually because we are using AppKit lifecycle
                         // so navigationTitle no longer works.
-                        guard let window = self.window else { return }
+                        self.window.title = newValue
-                        window.title = newValue
+                    }
+                    .onChange(of: cellSize) { newValue in
+                        if !ghostty.windowStepResize { return }
+                        guard let size = newValue else { return }
+                        self.window.contentResizeIncrements = size
                     }
             }
         }
@@ -95,8 +100,7 @@ struct PrimaryView: View {
         // Notification center indiscriminately sends to every subscriber (makes sense)
         // but we only want to process this once. In order to process it once lets only
         // handle it if we're the focused window.
-        guard let window = self.window else { return }
+        guard self.window.isKeyWindow else { return }
-        guard window.isKeyWindow else { return }
         
         // Get the tab index from the notification
         guard let tabIndexAny = notification.userInfo?[Ghostty.Notification.GotoTabKey] else { return }
@@ -135,8 +139,7 @@ struct PrimaryView: View {
         // Just like in `onGotoTab`, we might receive this multiple times. But
         // it's fine, because `toggleFullscreen` should only apply to the
         // currently focused window.
-        guard let window = self.window else { return }
+        guard self.window.isKeyWindow else { return }
-        guard window.isKeyWindow else { return }
 
         // Check whether we use non-native fullscreen
         guard let useNonNativeFullscreenAny = notification.userInfo?[Ghostty.Notification.NonNativeFullscreenKey] else { return }

macos/Sources/Features/Primary Window/PrimaryWindow.swift

@@ -41,7 +41,8 @@ class PrimaryWindow: NSWindow {
             ghostty: ghostty,
             appDelegate: appDelegate,
             focusedSurfaceWrapper: window.focusedSurfaceWrapper,
-            baseConfig: baseConfig
+            baseConfig: baseConfig,
+            window: window
         ))
         
         // We do want to cascade when new windows are created

macos/Sources/Ghostty/AppState.swift

@@ -97,6 +97,15 @@ extension Ghostty {
             return String(cString: ptr)
         }
         
+        /// Whether to resize windows in discrete steps or use "fluid" resizing
+        var windowStepResize: Bool {
+            guard let config = self.config else { return true }
+            var v = false
+            let key = "window-step-resize"
+            _ = ghostty_config_get(config, &v, key, UInt(key.count))
+            return v
+        }
+
         /// The background opacity.
         var backgroundOpacity: Double {
             guard let config = self.config else { return 1 }
@@ -143,7 +152,8 @@ extension Ghostty {
                 goto_tab_cb: { userdata, n in AppState.gotoTab(userdata, n: n) },
                 toggle_fullscreen_cb: { userdata, nonNativeFullscreen in AppState.toggleFullscreen(userdata, nonNativeFullscreen: nonNativeFullscreen) },
                 set_initial_window_size_cb: { userdata, width, height in AppState.setInitialWindowSize(userdata, width: width, height: height) },
-                render_inspector_cb: { userdata in AppState.renderInspector(userdata) }
+                render_inspector_cb: { userdata in AppState.renderInspector(userdata) },
+                set_cell_size_cb: { userdata, width, height in AppState.setCellSize(userdata, width: width, height: height) }
             )
 
             // Create the ghostty app.
@@ -468,6 +478,12 @@ extension Ghostty {
             surfaceView.initialSize = NSMakeSize(Double(width), Double(height))
         }
 
+        static func setCellSize(_ userdata: UnsafeMutableRawPointer?, width: UInt32, height: UInt32) {
+            guard let surfaceView = self.surfaceUserdata(from: userdata) else { return }
+            let backingSize = NSSize(width: Double(width), height: Double(height))
+            surfaceView.cellSize = surfaceView.convertFromBacking(backingSize)
+        }
+
         static func newTab(_ userdata: UnsafeMutableRawPointer?, config: ghostty_surface_config_s) {
             guard let surface = self.surfaceUserdata(from: userdata) else { return }
             

macos/Sources/Ghostty/SurfaceView.swift

@@ -78,6 +78,7 @@ extension Ghostty {
                         .focused($surfaceFocus)
                         .focusedValue(\.ghosttySurfaceTitle, surfaceView.title)
                         .focusedValue(\.ghosttySurfaceView, surfaceView)
+                        .focusedValue(\.ghosttySurfaceCellSize, surfaceView.cellSize)
                         .onReceive(pubBecomeKey) { notification in
                             guard let window = notification.object as? NSWindow else { return }
                             guard let surfaceWindow = surfaceView.window else { return }
@@ -241,6 +242,12 @@ extension Ghostty {
         // to the app level and it is set from there.
         @Published var title: String = "👻"
 
+        // The cell size of this surface. This is set by the core when the
+        // surface is first created and any time the cell size changes (i.e.
+        // when the font size changes). This is used to allow windows to be
+        // resized in discrete steps of a single cell.
+        @Published var cellSize: NSSize = .zero
+
         // An initial size to request for a window. This will only affect
         // then the view is moved to a new window.
         var initialSize: NSSize? = nil
@@ -930,3 +937,14 @@ extension FocusedValues {
         typealias Value = Bool
     }
 }
+
+extension FocusedValues {
+    var ghosttySurfaceCellSize: NSSize? {
+        get { self[FocusedGhosttySurfaceCellSize.self] }
+        set { self[FocusedGhosttySurfaceCellSize.self] = newValue }
+    }
+
+    struct FocusedGhosttySurfaceCellSize: FocusedValueKey {
+        typealias Value = NSSize
+    }
+}

macos/Sources/Helpers/WindowAccessor.swift

@@ -1,16 +0,0 @@
-import SwiftUI
-
-/// Allows accessing the window that this view is a part of.
-struct WindowAccessor: NSViewRepresentable {
-    @Binding var window: NSWindow?
-    
-    func makeNSView(context: Context) -> NSView {
-        let view = NSView()
-        DispatchQueue.main.async {
-            self.window = view.window
-        }
-        return view
-    }
-    
-    func updateNSView(_ nsView: NSView, context: Context) {}
-}

src/Surface.zig

@@ -460,6 +460,9 @@ pub fn init(
         .config = try DerivedConfig.init(alloc, config),
     };
 
+    // Report initial cell size on surface creation
+    try rt_surface.setCellSize(cell_size.width, cell_size.height);
+
     // Set a minimum size that is cols=10 h=4. This matches Mac's Terminal.app
     // but is otherwise somewhat arbitrary.
     try rt_surface.setSizeLimits(.{
@@ -896,6 +899,9 @@ fn setCellSize(self: *Surface, size: renderer.CellSize) !void {
         },
     }, .{ .forever = {} });
     self.io_thread.wakeup.notify() catch {};
+
+    // Notify the window
+    try self.rt_surface.setCellSize(size.width, size.height);
 }
 
 /// Change the font size.

src/apprt/embedded.zig

@@ -98,6 +98,9 @@ pub const App = struct {
 
         /// Render the inspector for the given surface.
         render_inspector: ?*const fn (SurfaceUD) callconv(.C) void = null,
+
+        /// Called when the cell size changes.
+        set_cell_size: ?*const fn (SurfaceUD, u32, u32) callconv(.C) void = null,
     };
 
     /// Special values for the goto_tab callback.
@@ -818,6 +821,15 @@ pub const Surface = struct {
         func(self.opts.userdata);
     }
 
+    pub fn setCellSize(self: *const Surface, width: u32, height: u32) !void {
+        const func = self.app.opts.set_cell_size orelse {
+            log.info("runtime embedder does not support set_cell_size", .{});
+            return;
+        };
+
+        func(self.opts.userdata, width, height);
+    }
+
     fn newSurfaceOptions(self: *const Surface) apprt.Surface.Options {
         const font_size: u16 = font_size: {
             if (!self.app.config.@"window-inherit-font-size") break :font_size 0;

src/apprt/glfw.zig

@@ -461,6 +461,13 @@ pub const Surface = struct {
         self.window.setSize(.{ .width = width, .height = height });
     }
 
+    /// Set the cell size. Unused by GLFW.
+    pub fn setCellSize(self: *const Surface, width: u32, height: u32) !void {
+        _ = self;
+        _ = width;
+        _ = height;
+    }
+
     /// Set the size limits of the window.
     /// Note: this interface is not good, we should redo it if we plan
     /// to use this more. i.e. you can't set max width but no max height,

src/apprt/gtk/Surface.zig

@@ -374,6 +374,12 @@ pub fn setInitialWindowSize(self: *const Surface, width: u32, height: u32) !void
     );
 }
 
+pub fn setCellSize(self: *const Surface, width: u32, height: u32) !void {
+    _ = self;
+    _ = width;
+    _ = height;
+}
+
 pub fn setSizeLimits(self: *Surface, min: apprt.SurfaceSize, max_: ?apprt.SurfaceSize) !void {
     _ = self;
     _ = min;

src/config/Config.zig

@@ -390,6 +390,11 @@ keybind: Keybinds = .{},
 @"window-height": u32 = 0,
 @"window-width": u32 = 0,
 
+/// Resize the window in discrete increments of the focused surface's
+/// cell size. If this is disabled, surfaces are resized in pixel increments.
+/// Currently only supported on macOS.
+@"window-step-resize": bool = true,
+
 /// Whether to allow programs running in the terminal to read/write to
 /// the system clipboard (OSC 52, for googling). The default is to
 /// disallow clipboard reading but allow writing.