From 3e4327ddbf19973812e19a0449711c8160f7670e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jochen=20G=C3=B6rtler?= <me@jgoertler.com>
Date: Wed, 20 Nov 2024 20:20:23 +0100
Subject: [PATCH] WIP: fix panic

---
 crates/viewer/re_space_view_graph/src/layout/mod.rs |  5 +++++
 crates/viewer/re_space_view_graph/src/ui/state.rs   | 11 +++++++++++
 crates/viewer/re_space_view_graph/src/view.rs       | 12 ++++++++----
 3 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/crates/viewer/re_space_view_graph/src/layout/mod.rs b/crates/viewer/re_space_view_graph/src/layout/mod.rs
index 5d13b5d33806..1fb86dcef958 100644
--- a/crates/viewer/re_space_view_graph/src/layout/mod.rs
+++ b/crates/viewer/re_space_view_graph/src/layout/mod.rs
@@ -27,6 +27,11 @@ impl Layout {
             .get_mut(node)
             .expect("node should exist in layout") = rect;
     }
+
+    /// Returns `true` if any node has a zero size.
+    pub fn has_zero_size(&self) -> bool {
+        self.extents.values().any(|r| r.size() == Vec2::ZERO)
+    }
 }
 
 impl<'a> From<&'a NodeInstance> for fj::Node {
diff --git a/crates/viewer/re_space_view_graph/src/ui/state.rs b/crates/viewer/re_space_view_graph/src/ui/state.rs
index 499236f62bbd..ff23e75773e0 100644
--- a/crates/viewer/re_space_view_graph/src/ui/state.rs
+++ b/crates/viewer/re_space_view_graph/src/ui/state.rs
@@ -1,6 +1,7 @@
 use egui::Rect;
 use re_chunk::{TimeInt, Timeline};
 use re_format::format_f32;
+use re_log::external::log;
 use re_types::blueprint::components::VisualBounds2D;
 use re_ui::UiExt;
 use re_viewer_context::SpaceViewState;
@@ -137,6 +138,16 @@ impl LayoutState {
                     provider,
                 }
             }
+            Self::InProgress { ref timestamp, .. } if timestamp != &requested => {
+                let provider = ForceLayout::new(graphs);
+                let layout = provider.init_layout();
+
+                Self::InProgress {
+                    timestamp: requested,
+                    layout,
+                    provider,
+                }
+            }
             // We keep iterating on the layout until it is stable.
             Self::InProgress {
                 timestamp,
diff --git a/crates/viewer/re_space_view_graph/src/view.rs b/crates/viewer/re_space_view_graph/src/view.rs
index b51018243da5..5bb9c17a697f 100644
--- a/crates/viewer/re_space_view_graph/src/view.rs
+++ b/crates/viewer/re_space_view_graph/src/view.rs
@@ -151,6 +151,7 @@ impl SpaceViewClass for GraphSpaceView {
             query.latest_at,
             graphs.iter().map(|(_, graph)| graph),
         );
+        let needs_remeasure = layout.has_zero_size();
 
         state.world_bounds = Some(bounds);
         let bounds_rect: egui::Rect = bounds.into();
@@ -169,8 +170,8 @@ impl SpaceViewClass for GraphSpaceView {
 
                 // Draw explicit nodes.
                 for node in graph.nodes_explicit() {
-                    let pos = layout.get(&node.index).unwrap_or(egui::Rect::ZERO); // TODO(grtlr): sometimes there just isn't any data.
-                                                                                   // .expect("explicit node should be in layout");
+                    let pos = layout.get(&node.index).unwrap_or(egui::Rect::ZERO);
+
                     let response = scene.explicit_node(pos.min, node);
                     entity_rect = entity_rect.union(response.rect);
                     layout.update(&node.index, response.rect);
@@ -178,8 +179,7 @@ impl SpaceViewClass for GraphSpaceView {
 
                 // Draw implicit nodes.
                 for node in graph.nodes_implicit() {
-                    let current = layout.get(&node.index).unwrap_or(egui::Rect::ZERO); // TODO(grtlr): sometimes there just isn't any data.
-                                                                                       // .expect("implicit node should be in layout");
+                    let current = layout.get(&node.index).unwrap_or(egui::Rect::ZERO);
                     let response = scene.implicit_node(current.min, node);
                     entity_rect = entity_rect.union(response.rect);
                     layout.update(&node.index, response.rect);
@@ -220,6 +220,10 @@ impl SpaceViewClass for GraphSpaceView {
         // Update stored bounds on the state, so visualizers see an up-to-date value.
         state.world_bounds = Some(bounds);
 
+        if needs_remeasure {
+            ui.ctx().request_discard("layout needed a remeasure");
+        }
+
         if state.layout_state.is_in_progress() {
             ui.ctx().request_repaint();
         }