fix(editor): fit blank frame on startup

crates/op-editor-core/src/viewport.rs

@@ -45,6 +45,17 @@ impl Viewport {
     /// the content centre to the canvas centre. No-op for an empty
     /// content rect or a degenerate canvas.
     pub fn fit_to(&mut self, content: Rect, canvas_w: f32, canvas_h: f32, padding: f32) {
+        self.fit_to_with_max_zoom(content, canvas_w, canvas_h, padding, Self::MAX_ZOOM);
+    }
+
+    pub fn fit_to_with_max_zoom(
+        &mut self,
+        content: Rect,
+        canvas_w: f32,
+        canvas_h: f32,
+        padding: f32,
+        max_zoom: f32,
+    ) {
         if content.size.x <= 0.0 || content.size.y <= 0.0 || canvas_w <= 0.0 || canvas_h <= 0.0 {
             return;
         }
@@ -52,7 +63,10 @@ impl Viewport {
         let avail_h = (canvas_h - 2.0 * padding).max(1.0);
         let zoom = (avail_w / content.size.x)
             .min(avail_h / content.size.y)
-            .clamp(Self::MIN_ZOOM, Self::MAX_ZOOM);
+            .clamp(
+                Self::MIN_ZOOM,
+                max_zoom.clamp(Self::MIN_ZOOM, Self::MAX_ZOOM),
+            );
         let cc_x = content.origin.x + content.size.x / 2.0;
         let cc_y = content.origin.y + content.size.y / 2.0;
         self.zoom = zoom;
@@ -118,6 +132,21 @@ mod tests {
         assert!((v.pan_y + 325.0 * v.zoom - 200.0).abs() < 1e-2);
     }
 
+    #[test]
+    fn fit_to_with_max_zoom_caps_content_fit() {
+        let mut v = Viewport::IDENTITY;
+        let content = Rect {
+            origin: Point2D::new(100.0, 50.0),
+            size: Point2D::new(200.0, 100.0),
+        };
+
+        v.fit_to_with_max_zoom(content, 1000.0, 800.0, 100.0, 2.0);
+
+        assert_eq!(v.zoom, 2.0);
+        assert!((v.pan_x - 100.0).abs() < 1e-2, "pan_x {}", v.pan_x);
+        assert!((v.pan_y - 200.0).abs() < 1e-2, "pan_y {}", v.pan_y);
+    }
+
     #[test]
     fn fit_to_ignores_empty_content() {
         let mut v = Viewport::IDENTITY;

crates/op-host-desktop/src/main.rs

@@ -159,8 +159,12 @@ struct DesktopApp {
 impl DesktopApp {
     fn new(initial_file: Option<PathBuf>) -> Self {
         let mut host = WidgetHostNative::new();
+        let fit_blank_frame = initial_file.is_none();
         // Best-effort prefs restore onto the host's `EditorState`.
         settings_io::load(host.editor_state_mut());
+        if fit_blank_frame {
+            host.fit_content_to_viewport(INITIAL_VIEWPORT_W, INITIAL_VIEWPORT_H);
+        }
         host.mark_editor_state_dirty();
         // Baseline for the unsaved-changes prompt — the fresh,
         // empty document is by definition "saved" (nothing to lose).

crates/op-host-desktop/src/main_tests.rs

@@ -34,3 +34,13 @@ fn cursor_redraw_still_paints_when_layer_hover_changes() {
 
     assert!(app.prepare_redraw());
 }
+
+#[test]
+fn fresh_app_fits_blank_frame_like_ts_canvas_init() {
+    let app = DesktopApp::new(None);
+    let v = app.host.editor_state().viewport;
+
+    assert!((v.zoom - 0.66).abs() < 1e-3, "zoom {}", v.zoom);
+    assert!((v.pan_x - 64.0).abs() < 1e-2, "pan_x {}", v.pan_x);
+    assert!((v.pan_y - 166.0).abs() < 1e-2, "pan_y {}", v.pan_y);
+}

crates/op-host-desktop/src/persistence.rs

@@ -426,7 +426,7 @@ pub fn run_action(
     match action {
         FileAction::New => {
             // Reset the document to a fresh untitled state.
-            *host.editor_state_mut() = EditorState::new();
+            *host.editor_state_mut() = EditorState::starter();
             host.mark_editor_state_dirty();
             *current_path = None;
             refresh_title(current_path, window);
@@ -702,6 +702,45 @@ mod tests {
         );
     }
 
+    #[test]
+    fn new_file_action_resets_to_starter_frame() {
+        let mut host = WidgetHostNative::new();
+        host.editor_state_mut().doc.children.clear();
+        let mut current_path = Some(PathBuf::from("/tmp/old.op"));
+
+        let outcome = run_action(
+            op_editor_core::editor_ui_state::FileAction::New,
+            &mut host,
+            &mut current_path,
+            None,
+        );
+
+        assert_eq!(outcome, ActionOutcome::Saved);
+        assert!(current_path.is_none());
+        assert_eq!(host.editor_state().doc.children.len(), 1);
+        assert_eq!(
+            host.editor_state().selection.anchor,
+            op_editor_core::NodeId::new("n10")
+        );
+        let frame = match &host.editor_state().doc.children[0] {
+            jian_ops_schema::node::PenNode::Frame(frame) => frame,
+            other => panic!(
+                "new file should create the blank starter frame, got {:?}",
+                other
+            ),
+        };
+        assert_eq!(frame.base.x, Some(0.0));
+        assert_eq!(frame.base.y, Some(0.0));
+        assert!(matches!(
+            frame.container.width,
+            Some(jian_ops_schema::sizing::SizingBehavior::Number(1200.0))
+        ));
+        assert!(matches!(
+            frame.container.height,
+            Some(jian_ops_schema::sizing::SizingBehavior::Number(800.0))
+        ));
+    }
+
     #[test]
     fn legacy_doc_payload_is_detected() {
         // Fix 4: a pre-canonical private `DocPayload` JSON (integer

crates/op-host-native/src/widget_host.rs

@@ -64,6 +64,7 @@ mod settings_dispatch;
 mod shape_picker_press;
 mod shortcuts;
 mod toolbar_hover;
+mod viewport_fit;
 
 pub use frame_backend::NativeFrameBackend;
 

crates/op-host-native/src/widget_host/geometry.rs

@@ -486,7 +486,7 @@ impl WidgetHostNative {
         let (_l, _t, canvas_w, canvas_h) = self.canvas_region(viewport_w, viewport_h);
         self.editor_state
             .viewport
-            .fit_to(content, canvas_w, canvas_h, 48.0);
+            .fit_to_with_max_zoom(content, canvas_w, canvas_h, 64.0, 1.0);
         self.mark_dirty();
     }
 

crates/op-host-native/src/widget_host/input_tests.rs

@@ -196,17 +196,9 @@ fn status_bar_search_click_frames_content_in_viewport() {
 
     assert!(consumed, "search-icon click must be consumed");
     let v = host.editor_state().viewport;
-    assert!(
-        (v.zoom - 0.2).abs() > 1e-3,
-        "zoom should change to frame the content, got {}",
-        v.zoom
-    );
-    assert!(
-        v.pan_x > -5000.0 && v.pan_y > -5000.0,
-        "pan should re-anchor toward the content, got ({}, {})",
-        v.pan_x,
-        v.pan_y
-    );
+    assert!((v.zoom - 1.0).abs() < 1e-3, "zoom {}", v.zoom);
+    assert!((v.pan_x - 230.0).abs() < 1e-2, "pan_x {}", v.pan_x);
+    assert!((v.pan_y - 180.0).abs() < 1e-2, "pan_y {}", v.pan_y);
 }
 
 #[test]

crates/op-host-native/src/widget_host/viewport_fit.rs

@@ -0,0 +1,9 @@
+//! Public viewport-fit adapter for desktop runner startup.
+
+use super::WidgetHostNative;
+
+impl WidgetHostNative {
+    pub fn fit_content_to_viewport(&mut self, viewport_w: f32, viewport_h: f32) {
+        self.zoom_to_fit(viewport_w, viewport_h);
+    }
+}

crates/op-host-web/src/widget_host/press.rs

@@ -57,7 +57,7 @@ impl WidgetHost {
         let (_l, _t, canvas_w, canvas_h) = self.canvas_region(viewport_w, viewport_h);
         self.editor_state
             .viewport
-            .fit_to(content, canvas_w, canvas_h, 48.0);
+            .fit_to_with_max_zoom(content, canvas_w, canvas_h, 64.0, 1.0);
         self.mark_dirty();
     }
 }