Fix relations drawn on non existent notes

src/js/action/draw.js

@@ -206,15 +206,19 @@ export function draw_metarelation(draw_context, mei_graph, g_elem) {
   var type = relation_type(g_elem)
   // Get the targets - we don't differentiate primaries and secondaries in
   // this drawing style.
-  var targets = relation_allnodes(mei_graph, g_elem).map(
-    (e) => document.getElementById(draw_context.id_prefix + get_id(e)))
-  // TODO should be possible to draw partial metarelations
-  if (targets.indexOf(null) != -1) {
+  var targets = relation_allnodes(mei_graph, g_elem).map((e) => {
+    let he = document.getElementById(draw_context.id_prefix + get_id(e))
+    if (!he) return
+    return he.classList.contains('hidden-reduced') ? null : he
+  })
+  if (!targets[0]) {
     console.log('Missing relation, not drawing metarelation')
     return []
   }
 
-  const isDownward = targets.every(target => target.getAttribute('is-downward') === 'true')
+  const isDownward = targets.every(
+    target => target.getAttribute('is-downward') === 'true'
+  )
 
   // Where are our targets
   var coords = targets.map(target => {

src/js/modules/Score/index.js

@@ -36,7 +36,10 @@ class Score {
   // Cached members.
 
   get flatSelection() {
-    return this.#cache.remember('flatSelection', () => Object.values(this.selection).flat())
+    return this.#cache.remember('flatSelection',
+      () => this.selection
+        ? Object.values(this.selection).flat()
+        : null)
   }
 
   get hasSelection() {
@@ -46,7 +49,9 @@ class Score {
   get selectionType() {
     return this.#cache.remember('selectionType', () => {
       return SELECTABLE_TYPES.find(type => {
-        return this.flatSelection[0]?.classList.contains(type)
+        return this.flatSelection
+          ? this.flatSelection[0]?.classList.contains(type)
+          : null
       }) ?? null
     })
   }

src/js/utils/misc.js

@@ -373,6 +373,8 @@ export function id_in_svg(draw_context, id) {
   // that's how it is), then dc.id_prefix to calculate the final id
   var layer_id = id_in_layer(draw_context.layer, id)
   var svg_note = document.getElementById(layer_id)
+  if (svg_note && svg_note.classList.contains('hidden-reduced'))
+    return null
   if (draw_context.svg_elem.contains(svg_note))
     return layer_id
   if (layer_id)