From 90d24f9e82dbda769f9fcebd9ddafb8f1a9f3aeb Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <m@mitchellh.com>
Date: Thu, 29 Aug 2024 14:54:58 -0700
Subject: [PATCH] macos: get updated surface size metrics immediately on resize

Fixes #2149

Previously, the way we were getting the updated surface size would use
outdated (previous) values because the resize event was not processed by
the surface before the SwiftUI view processed the resize overlay. And
since the property we used wasn't `@Published`, we didn't get notified
when we got that updated value.
---
 .../Sources/Ghostty/SurfaceView_AppKit.swift  | 26 ++++++++++++-------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/macos/Sources/Ghostty/SurfaceView_AppKit.swift b/macos/Sources/Ghostty/SurfaceView_AppKit.swift
index 2051a5610..0daa6a68f 100644
--- a/macos/Sources/Ghostty/SurfaceView_AppKit.swift
+++ b/macos/Sources/Ghostty/SurfaceView_AppKit.swift
@@ -34,6 +34,10 @@ extension Ghostty {
         // on supported platforms.
         @Published var focusInstant: Any? = nil
 
+        // Returns sizing information for the surface. This is the raw C
+        // structure because I'm lazy.
+        @Published var surfaceSize: ghostty_surface_size_s? = nil
+
         // 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
@@ -55,14 +59,6 @@ extension Ghostty {
             if (v.count == 0) { return nil }
             return v
         }
-
-        // Returns sizing information for the surface. This is the raw C
-        // structure because I'm lazy.
-        var surfaceSize: ghostty_surface_size_s? {
-            guard let surface = self.surface else { return nil }
-            return ghostty_surface_size(surface)
-        }
-
         // Returns the inspector instance for this surface, or nil if the
         // surface has been closed.
         var inspector: ghostty_inspector_t? {
@@ -229,7 +225,7 @@ extension Ghostty {
             // an animation (i.e. a fullscreen animation), the frame will not yet be updated.
             // The size represents our final size we're going for.
             let scaledSize = self.convertToBacking(size)
-            ghostty_surface_set_size(surface, UInt32(scaledSize.width), UInt32(scaledSize.height))
+            setSurfaceSize(width: UInt32(scaledSize.width), height: UInt32(scaledSize.height))
 
             // Frame changes do not always call mouseEntered/mouseExited, so we do some
             // calculations ourself to call those events.
@@ -251,6 +247,16 @@ extension Ghostty {
             }
         }
 
+        private func setSurfaceSize(width: UInt32, height: UInt32) {
+            guard let surface = self.surface else { return }
+
+            // Update our core surface
+            ghostty_surface_set_size(surface, width, height)
+
+            // Update our cached size metrics
+            self.surfaceSize = ghostty_surface_size(surface)
+        }
+
         func setCursorShape(_ shape: ghostty_mouse_shape_e) {
             switch (shape) {
             case GHOSTTY_MOUSE_SHAPE_DEFAULT:
@@ -441,7 +447,7 @@ extension Ghostty {
             ghostty_surface_set_content_scale(surface, xScale, yScale)
 
             // When our scale factor changes, so does our fb size so we send that too
-            ghostty_surface_set_size(surface, UInt32(fbFrame.size.width), UInt32(fbFrame.size.height))
+            setSurfaceSize(width: UInt32(fbFrame.size.width), height: UInt32(fbFrame.size.height))
         }
 
         override func updateLayer() {