Of course. This is a great evolution of the highlighting logic. We are now creating a very informative and visually rich display based on your selection.
**Our Next Goal:** When a node is selected from the slicer:
1. The **selected node** itself turns **green**.
2. The entire path of **parent nodes** above it turns **red**.
3. The entire sub-tree of **child nodes** below it turns **amber** (yellow/orange).
4. All other nodes are white.
The Power BI setup is already perfect for this. We just need to add more sophisticated logic to our Deneb JSON.
-----
### **Deneb JSON Modifications**
#### **Step 1: Add New Signals to Identify Parents and Children**
We need to give the visual the ability to distinguish between parents and children. To do this, we'll add two new signals.
1. Open the Deneb editor.
2. Find the `"signals": [...]` array.
3. Add the following two signals inside the array, right after the `slicerHighlightPath` signal.
<!-- end list -->
```json
{
"name": "slicerParentPath",
"value": [],
"update": "slicerSelection ? slice(slicerHighlightPath, 0, -1) : []"
},
{
"name": "slicerDescendantsPath",
"value": [],
"update": "slicerSelection ? pluck(filter(data('treeCalcs'), test(regexp('^' + slicerSelection), datum.id)), 'id') : []"
}
```
**Explanation:**
* **`slicerParentPath`**: This takes the full ancestor path (`slicerHighlightPath`) and cleverly removes the last item (the selected node itself), leaving us with an array of *only* the parents.
* **`slicerDescendantsPath`**: This finds all children, grandchildren, etc., below your selection. It also includes the selected node itself, but our coloring logic will handle that.
#### **Step 2: Update the Node Color Logic**
This is the main change. We will replace the `fill` and `stroke` logic for the nodes with a new set of rules that checks for all three colors.
1. Scroll down to the `"marks": [...]` array and find the group mark with `"name": "node"`.
2. Inside its `"encode": { "update": { ... } }` block, **replace** the `fill` and `stroke` properties with these new, more advanced ones:
<!-- end list -->
```json
"fill": {
"signal": "slicerSelection && slicerSelection !== '' ? (datum.id === slicerSelection ? '#d4edda' : indexof(slicerParentPath, datum.id) > -1 ? '#f8d7da' : indexof(slicerDescendantsPath, datum.id) > -1 ? '#fff3cd' : '#ffffff') : merge(hsl(scale('colour', datum.treeParent)), {l:0.94})"
},
"stroke": {
"signal": "slicerSelection && slicerSelection !== '' ? (datum.id === slicerSelection ? '#155724' : indexof(slicerParentPath, datum.id) > -1 ? '#721c24' : indexof(slicerDescendantsPath, datum.id) > -1 ? '#856404' : '#d3d3d3') : merge(hsl(scale('colour', datum.treeParent)), {l:0.79})"
},
```
**How this new code works:**
It's a nested conditional check that follows a clear priority:
1. Is the node the **selected one**? If yes, make it **green**.
2. If not, is it in the **parent path**? If yes, make it **red**.
3. If not, is it in the **descendant path**? If yes, make it **amber**.
4. If none of the above, make it **white**.
5. If nothing is selected at all, it shows the original chart colors.
#### **Step 3: Update the Link Colors to Match**
Finally, let's make the connecting lines match the new color scheme.
1. In the `"marks"` array, find the first mark (`"type": "path"`).
2. **Replace** its `"stroke"` property with the following code:
<!-- end list -->
```json
"stroke": {
"signal": "slicerSelection && slicerSelection !== '' ? (indexof(slicerHighlightPath, datum.target.id) > -1 ? '#721c24' : indexof(slicerDescendantsPath, datum.target.id) > -1 ? '#856404' : '#d3d3d3') : scale('colour', reverse(pluck(treeAncestors('treeCalcs', datum.target.id), 'id'))[1])"
}
```
**How this new code works:**
1. Is the link part of the path leading to the selected node (`slicerHighlightPath`)? If yes, make the line a dark **red**.
2. If not, is the link part of the descendant sub-tree? If yes, make the line a dark **amber**.
3. If neither, make the line light **grey**.
#### **Step 4: Apply Changes**
Click the "Apply" button in the Deneb editor.
Your visual is now incredibly dynamic. Selecting a single node will instantly give you a colored view of its entire context within the hierarchy: its ancestry in red, itself in green, and its descendants in amber.
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