Add device visibility controls: right-click hide and top bar type toggles

- Right-click context menu: "Hide" option to hide individual symbols
- "Show All Hidden" appears in context menu when anything is hidden
- Top visibility bar with toggle chips for each device group
- Hidden symbols are excluded from rendering, hit testing, and SVG export

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

svelte-app/src/components/Canvas.svelte

@@ -84,6 +84,21 @@
     contextMenu = null;
   }
 
+  function handleHide() {
+    if (!contextMenu) return;
+    if (layout.selectedIds.has(contextMenu.symId) && layout.selectedIds.size > 1) {
+      layout.hideSelected();
+    } else {
+      layout.toggleSymbolHidden(contextMenu.symId);
+    }
+    contextMenu = null;
+  }
+
+  function handleShowAll() {
+    layout.showAllHidden();
+    contextMenu = null;
+  }
+
   function handleSetLabel() {
     if (!contextMenu) return;
     const sym = layout.symbols.find(s => s.id === contextMenu!.symId);
@@ -142,7 +157,12 @@
     <button class="context-menu-item" onclick={handleSetLabel} role="menuitem">Set ID</button>
     <button class="context-menu-item" onclick={handleMirror} role="menuitem">Mirror</button>
     <button class="context-menu-item" onclick={handleDuplicate} role="menuitem">Duplicate</button>
+    <button class="context-menu-item" onclick={handleHide} role="menuitem">Hide</button>
     <button class="context-menu-item" onclick={handleDelete} role="menuitem">Delete</button>
+    {#if layout.symbols.some(s => s.hidden) || layout.hiddenGroups.size > 0}
+      <div class="context-menu-divider"></div>
+      <button class="context-menu-item" onclick={handleShowAll} role="menuitem">Show All Hidden</button>
+    {/if}
   </div>
 {/if}
 
@@ -222,4 +242,10 @@
   .context-menu-item:hover {
     background: #e94560;
   }
+
+  .context-menu-divider {
+    height: 1px;
+    background: #0f3460;
+    margin: 4px 0;
+  }
 </style>

svelte-app/src/components/VisibilityBar.svelte

@@ -0,0 +1,80 @@
+<script lang="ts">
+  import { layout } from '$lib/stores/layout.svelte.js';
+  import { SYMBOL_GROUPS } from '$lib/symbols.js';
+
+  function toggle(group: string) {
+    layout.toggleGroupHidden(group);
+  }
+
+  let hasHidden = $derived(layout.symbols.some(s => s.hidden));
+</script>
+
+<div class="visibility-bar">
+  {#each SYMBOL_GROUPS as group}
+    <button
+      class="group-chip"
+      class:hidden-group={layout.hiddenGroups.has(group)}
+      onclick={() => toggle(group)}
+      title={layout.hiddenGroups.has(group) ? `Show ${group}` : `Hide ${group}`}
+    >
+      {group}
+    </button>
+  {/each}
+  {#if hasHidden}
+    <button class="show-all-btn" onclick={() => layout.showAllHidden()}>
+      Show Hidden
+    </button>
+  {/if}
+</div>
+
+<style>
+  .visibility-bar {
+    display: flex;
+    align-items: center;
+    gap: 6px;
+    padding: 4px 8px;
+    background: #1a1a2e;
+    border-bottom: 1px solid #0f3460;
+    flex-shrink: 0;
+  }
+
+  .group-chip {
+    padding: 3px 10px;
+    font-size: 11px;
+    border-radius: 12px;
+    border: 1px solid #0f3460;
+    background: #16213e;
+    color: #e0e0e0;
+    cursor: pointer;
+    transition: all 0.15s;
+    user-select: none;
+  }
+
+  .group-chip:hover {
+    border-color: #e94560;
+  }
+
+  .group-chip.hidden-group {
+    background: transparent;
+    color: #555;
+    border-color: #333;
+    text-decoration: line-through;
+  }
+
+  .show-all-btn {
+    margin-left: auto;
+    padding: 3px 10px;
+    font-size: 11px;
+    border-radius: 12px;
+    border: 1px solid #e94560;
+    background: transparent;
+    color: #e94560;
+    cursor: pointer;
+    transition: all 0.15s;
+  }
+
+  .show-all-btn:hover {
+    background: #e94560;
+    color: #fff;
+  }
+</style>

svelte-app/src/lib/canvas/hit-testing.ts

@@ -1,6 +1,7 @@
 /** Pure hit-testing functions — no module state, no side effects */
 
-import { isResizable, isCurvedType, isSpurType, isEpcType, isInductionType, EPC_CONFIG, INDUCTION_CONFIG, getCurveGeometry } from '../symbols.js';
+import { isResizable, isCurvedType, isSpurType, isEpcType, isInductionType, getSymbolGroup, EPC_CONFIG, INDUCTION_CONFIG, getCurveGeometry } from '../symbols.js';
+import { layout } from '../stores/layout.svelte.js';
 import { THEME } from './render-theme.js';
 import type { PlacedSymbol } from '../types.js';
 
@@ -160,6 +161,7 @@ export function hitTestSymbols(
 ): number | null {
   for (let i = symbols.length - 1; i >= 0; i--) {
     const sym = symbols[i];
+    if (sym.hidden || layout.hiddenGroups.has(getSymbolGroup(sym.symbolId))) continue;
     const local = toSymbolLocal(cx, cy, sym);
     if (pointInSymbol(local.x, local.y, sym)) return sym.id;
   }

svelte-app/src/lib/canvas/renderer.ts

@@ -1,5 +1,5 @@
 import { layout } from '../stores/layout.svelte.js';
-import { getSymbolImage, isResizable, isCurvedType, isSpurType, isEpcType, isInductionType, isPhotoeyeType, getCurveGeometry, SPACING_EXEMPT, EPC_CONFIG, INDUCTION_CONFIG, PHOTOEYE_CONFIG } from '../symbols.js';
+import { getSymbolImage, isResizable, isCurvedType, isSpurType, isEpcType, isInductionType, isPhotoeyeType, getCurveGeometry, getSymbolGroup, SPACING_EXEMPT, EPC_CONFIG, INDUCTION_CONFIG, PHOTOEYE_CONFIG } from '../symbols.js';
 import { checkSpacingViolation } from './collision.js';
 import { THEME } from './render-theme.js';
 import type { PlacedSymbol } from '../types.js';
@@ -68,11 +68,14 @@ export function render() {
     drawGrid(ctx);
   }
 
-  // Draw non-overlay symbols first, then overlay symbols (photoeyes) on top
+  // Draw non-overlay symbols first, then overlay symbols (photoeyes/FIOs) on top
+  // Skip hidden symbols (individually hidden or group hidden)
   for (const sym of layout.symbols) {
+    if (sym.hidden || layout.hiddenGroups.has(getSymbolGroup(sym.symbolId))) continue;
     if (!SPACING_EXEMPT.has(sym.symbolId)) drawSymbol(ctx, sym as PlacedSymbol);
   }
   for (const sym of layout.symbols) {
+    if (sym.hidden || layout.hiddenGroups.has(getSymbolGroup(sym.symbolId))) continue;
     if (SPACING_EXEMPT.has(sym.symbolId)) drawSymbol(ctx, sym as PlacedSymbol);
   }
 
@@ -487,15 +490,23 @@ function drawSymbolOverlays(ctx: CanvasRenderingContext2D, sym: PlacedSymbol) {
     strokeOutline(ctx, sym, 0);
   }
 
-  // Label above symbol
+  // Label: centered inside symbol if large enough, above if too small
   if (sym.label) {
     ctx.fillStyle = THEME.label.color;
     ctx.font = THEME.label.font;
+    const metrics = ctx.measureText(sym.label);
+    const textH = 10; // approximate font height
+    if (sym.w >= metrics.width + 4 && sym.h >= textH + 4) {
+      ctx.textAlign = 'center';
+      ctx.textBaseline = 'middle';
+      ctx.fillText(sym.label, cx, sym.y + sym.h / 2);
+    } else {
       ctx.textAlign = 'center';
       ctx.textBaseline = 'bottom';
       ctx.fillText(sym.label, cx, sym.y + THEME.label.offsetY);
     }
   }
+}
 
 function drawSymbol(ctx: CanvasRenderingContext2D, sym: PlacedSymbol) {
   ctx.save();

svelte-app/src/lib/export.ts

@@ -1,5 +1,5 @@
 import { layout } from './stores/layout.svelte.js';
-import { isEpcType, isInductionType, isSpurType, isCurvedType, EPC_CONFIG, INDUCTION_CONFIG, getCurveGeometry } from './symbols.js';
+import { isEpcType, isInductionType, isSpurType, isCurvedType, getSymbolGroup, EPC_CONFIG, INDUCTION_CONFIG, getCurveGeometry } from './symbols.js';
 import { deserializeSymbol } from './serialization.js';
 import type { PlacedSymbol } from './types.js';
 
@@ -30,6 +30,7 @@ export async function exportSVG() {
   ];
 
   for (const sym of layout.symbols) {
+    if (sym.hidden || layout.hiddenGroups.has(getSymbolGroup(sym.symbolId))) continue;
     const rot = sym.rotation || 0;
     const mirrored = sym.mirrored || false;
     const cx = sym.x + sym.w / 2;

svelte-app/src/lib/stores/layout.svelte.ts

@@ -35,6 +35,9 @@ class LayoutStore {
   // Label-drag drop target highlight (symbol id or null)
   labelDropTarget = $state<number | null>(null);
 
+  // Visibility: hidden device type groups and count of individually hidden symbols
+  hiddenGroups = $state<Set<string>>(new Set());
+
   // Dirty flag for canvas re-render
   dirty = $state(0);
 
@@ -204,6 +207,58 @@ class LayoutStore {
     this.saveMcmState();
   }
 
+  toggleSymbolHidden(id: number) {
+    const sym = this.symbols.find(s => s.id === id);
+    if (!sym) return;
+    sym.hidden = !sym.hidden;
+    if (this.selectedIds.has(id)) {
+      const newSet = new Set(this.selectedIds);
+      newSet.delete(id);
+      this.selectedIds = newSet;
+    }
+    this.markDirty();
+    this.saveMcmState();
+  }
+
+  hideSelected() {
+    if (this.selectedIds.size === 0) return;
+    for (const id of this.selectedIds) {
+      const sym = this.symbols.find(s => s.id === id);
+      if (sym) sym.hidden = true;
+    }
+    this.selectedIds = new Set();
+    this.markDirty();
+    this.saveMcmState();
+  }
+
+  showAllHidden() {
+    let changed = false;
+    for (const sym of this.symbols) {
+      if (sym.hidden) {
+        sym.hidden = false;
+        changed = true;
+      }
+    }
+    if (this.hiddenGroups.size > 0) {
+      this.hiddenGroups = new Set();
+      changed = true;
+    }
+    if (changed) {
+      this.markDirty();
+    }
+  }
+
+  toggleGroupHidden(group: string) {
+    const newSet = new Set(this.hiddenGroups);
+    if (newSet.has(group)) {
+      newSet.delete(group);
+    } else {
+      newSet.add(group);
+    }
+    this.hiddenGroups = newSet;
+    this.markDirty();
+  }
+
   clearAll() {
     this.pushUndo();
     this.symbols = [];

svelte-app/src/lib/symbols.ts

@@ -72,6 +72,11 @@ export const SYMBOLS: SymbolDef[] = [
 
 export const SYMBOL_GROUPS = [...new Set(SYMBOLS.map(s => s.group))];
 
+const SYMBOL_GROUP_MAP = new Map(SYMBOLS.map(s => [s.id, s.group]));
+export function getSymbolGroup(symbolId: string): string {
+  return SYMBOL_GROUP_MAP.get(symbolId) || '';
+}
+
 export const PRIORITY_TYPES = new Set([
   'conveyor', 'conveyor_v', 'chute', 'chute_v',
   'tipper', 'tipper_v', 'extendo', 'extendo_v',

svelte-app/src/lib/types.ts

@@ -29,6 +29,7 @@ export interface PlacedSymbol {
   w2?: number; // Spur: top base width
   rotation: number;
   mirrored?: boolean; // Horizontal flip
+  hidden?: boolean; // Individually hidden via context menu
   curveAngle?: number; // For curved conveyors/chutes
   epcWaypoints?: EpcWaypoint[]; // EPC editable line waypoints (local coords)
   pdpCBs?: number[]; // PDP visible circuit breaker numbers (1-26)

svelte-app/src/routes/+page.svelte

@@ -2,6 +2,7 @@
   import { onMount } from 'svelte';
   import { preloadSymbolImages } from '$lib/symbols.js';
   import Toolbar from '../components/Toolbar.svelte';
+  import VisibilityBar from '../components/VisibilityBar.svelte';
   import Canvas from '../components/Canvas.svelte';
   import DeviceDock from '../components/DeviceDock.svelte';
 
@@ -20,7 +21,10 @@
 {#if ready}
   <div class="app">
     <Toolbar />
+    <div class="main-area">
+      <VisibilityBar />
       <Canvas />
+    </div>
     <DeviceDock />
   </div>
 {:else}
@@ -37,6 +41,13 @@
     overflow: hidden;
   }
 
+  .main-area {
+    display: flex;
+    flex-direction: column;
+    flex: 1;
+    min-width: 0;
+  }
+
   .loading {
     display: flex;
     flex-direction: column;