# Week 2 Task 4 - Click to Highlight / Select

## Objective
Implement a "Click to Select" pattern where clicking an object changes its visual state (glow, scale, or color).

## Vanilla three.js
- **Possible**: Yes
- **Notes**: Achieved using a `Raycaster` to detect mouse intersections with 3D objects. Requires manual math to convert mouse coordinates to NDC (Normalized Device Coordinates).
- **Key concepts**: Raycasting, Intersection detection, NDC conversion.
- **Complexity**: Medium-Hard (for beginners).

## R3F
- **Possible**: Yes
- **Notes**: Built-in support for pointer events directly on meshes (e.g., `<mesh onClick={...} />`). This is the industry standard for 3D web interactions.
- **What R3F abstracted**: Raycasting setup and event propagation.
- **Complexity**: Easy.

## Thob Page Builder
- **Possible**: **No / Partial**
- **Notes**: The 3D Mesh nodes do not support click or hover the triggers. The only way to "select" an object is through external UI buttons or RadioGroups.
- **Builder steps**: Create an external UI -> Assign a selection state -> Link that state to a 3D property (like Emissive intensity).
- **Complexity**: Hard (requires complex logic-linking to simulate a basic 3D interaction).

## Comparison Summary
- **Possible in all 3?**: **No**. Native 3D interaction is missing in Thob.
- **Main differences**: Vanilla/R3F allow clicking the object; Thob forces you to click a 2D UI button.
- **Where Thob is better**: Visual property animation is easy once triggered.
- **Where Thob is weaker**: Total lack of Scene-level Raycasting.
- **What feels awkward or unclear**: Trying to find interaction settings in the 3D properties panel, only to realize they don't exist yet.

## Limitation Type (if any)
- [ ] Editor UX limitation
- [ ] Runtime limitation
- [ ] Schema / data model limitation
- [ ] Component limitation
- [x] Event system limitation (Critical: No 3D Raycasting)
- [ ] Asset pipeline limitation

## Workaround
- **Is there a workaround?**: Yes. Offload all interaction to **2D UI Buttons** and use them as triggers for 3D state changes.

## Suggested Improvement
- **Primary Optimization**: Implement **3D Move/Click Triggers** on Mesh nodes. Thob needs an "Interactions" tab in the 3D Properties panel to allow users to trigger app-states directly from 3D objects.
- **Is it**: runtime, component, UX.

## Business Value
- **Medium-High**: Required for "Hotspots," "Guided Tours," and modern "Click-to-Configure" interiors.

## Product Lens
- **Is this pattern useful for real customers?**: Yes.
- **What kind of customer use case does this support?**: Virtual showrooms, architectural hotspots, and feature discovery points.
- **Does Thob feel strong enough for this use case?**: **No**. Without native 3D interaction, the experience feels "disconnected" compared to modern 3D apps.
- **What would improve the experience?**: Native pointer events on 3D meshes.

## Recommendation
Adding 3D Raycasting/Interactions should be a top priority roadmap item. It is the missing "bridge" that would allow designers to build truly immersive and interactive 3D digital products.