Property subscriptions allow you to monitor specific attributes of objects in real-time. The plugin supports Python expressions and provides intelligent autocomplete to help you explore object properties.
Entering Property Paths
To subscribe to a property:
Locate the property input field
At the bottom of each subscription box, you’ll find an input field with the placeholder “Enter property to subscribe”.
Enter a Python expression
Type the property name or Python expression you want to monitor. Examples:
- Simple property:
width
- Nested property:
transform.position.x
- Python expression:
len(tracks)
Configure update frequency (optional)
Set the update frequency in milliseconds (default: 50ms).
Subscribe
Click Subscribe or press Enter to add the property subscription.
<!-- From PropertyInput.vue:3-7 -->
<input
type="text"
v-model="inputValue"
placeholder="Enter property to subscribe"
@keyup.enter="emitSubscribe"
@keydown.tab.prevent="completeSuggestion"
:list="autocompleteListId"
/>
Autocomplete Feature
The plugin provides intelligent autocomplete suggestions as you type, powered by Python’s rlcompleter module.
How Autocomplete Works
Autocomplete suggestions appear automatically as you type and update in real-time with a 250ms debounce delay.
- Start typing - Suggestions appear in a dropdown as you type
- Select suggestion - Click a suggestion or press Tab to autocomplete
- Explore properties - Type
. after an object to see its attributes
Autocomplete Implementation
// From PropertyInput.vue:82-91
watchDebounced(inputValue, async (newValue) => {
if (newValue.trim()) {
const result = await autocomplete(props.objectName, newValue.trim());
suggestions.value = JSON.parse(result.returnValue) || [];
} else {
suggestions.value = [];
}
}, {
debounce: 250
});
Python Autocomplete Backend
The autocomplete functionality is powered by a Python script that evaluates the object context:
# From liveupdate_tester.py:7-30
def autocomplete(objExpr, propPath):
object = Expression.evaluateFromString(objExpr)
if object is None:
return None
names = dict(subscription_manager.__dict__)
names.update(object=object)
completer = Completer(names)
matches = []
index = 0
while len(matches) < 20: # Limit total results
match = completer.complete(propPath, index)
if match is None:
break
if '__' in match:
index += 1
continue
matches.append(match)
index += 1
return matches
The autocomplete filters out Python dunder methods (those containing __) and limits results to 20 suggestions for better performance.
Property Subscription Options
When subscribing to a property, you can configure its behavior:
Update Frequency
Control how often the property value is updated:
<!-- From PropertyInput.vue:19-26 -->
<div style="margin-top: 10px;">
<label for="update-frequency">Update Frequency (ms):</label>
<input
id="update-frequency"
type="number"
min="0"
v-model.number="updateFrequencyMs"
style="width: 100px; margin-left: 8px;"
/>
</div>
- Default value: 50ms (updates 20 times per second)
- Minimum value: 0ms (updates as fast as possible)
- Recommended range: 16ms-1000ms
Very low update frequencies (below 16ms) may impact performance, especially when monitoring many properties simultaneously.
Subscription Configuration
The subscription is created with your specified options:
// From PropertyInput.vue:57-68
const emitSubscribe = () => {
const property = inputValue.value.trim();
if (property) {
emit('subscribe', {
property,
options: {
updateFrequencyMs: updateFrequencyMs.value
}
});
inputValue.value = '';
}
};
Viewing Property Values in JSON Editor
Property values are displayed in an interactive JSON editor that supports:
- Tree view - Hierarchical display of complex objects
- Syntax highlighting - Color-coded JSON for better readability
- Collapsible nodes - Expand/collapse nested structures
- Real-time updates - Values update automatically at the configured frequency
<!-- From PropertySubscription.vue:4-5 -->
<td>
<JsonEditorVue v-model="jsonValue" :mode="Mode.tree" :navigation-bar="false" :main-menu-bar="false" />
</td>
Value Types
The JSON editor displays various value types:
Primitives
Objects
Arrays
Null
Simple values like strings, numbers, and booleans: Complex objects with nested properties:{
"x": 0.0,
"y": 0.0,
"z": 0.0
}
Lists of values:["track1", "track2", "track3"]
Null or undefined values: Unsubscribing from Properties
To stop monitoring a property:
- Locate the property row in the subscription table
- Click the trash icon in the Action column
- The property subscription will be removed immediately
// From ObjectSubscription.vue:90-92
const unsubscribe = (property: string) => {
subscriptions.value = subscriptions.value.filter(sub => sub.property !== property);
};
Unsubscribing from a property removes it from localStorage, so it won’t be restored when you reload the plugin.
Python Expression Examples
The plugin supports full Python expressions, not just simple property paths. This gives you powerful querying capabilities.
Basic Properties
Access simple object properties:
width
height
name
description
Nested Properties
Access nested attributes using dot notation:
transform.position.x
transform.rotation.y
transform.scale.z
# From ObjectSubscription.vue:96
type(object)
# Check if object is a Resource
# From ObjectSubscription.vue:97
isinstance(object, Resource)
Resource Properties
Access resource-specific properties:
# From ResourceInfo.vue:30-32
object.description
"0x{:x}".format(object.uid) # UID in hexadecimal
str(object.path) # Full resource path
Collection Operations
Work with lists and collections:
len(tracks) # Number of tracks
tracks[0].name # First track name
[t.name for t in tracks] # List of all track names
Computed Values
Perform calculations and transformations:
width * height # Calculate area
round(opacity * 100, 2) # Convert to percentage
str(uuid).upper() # Format UUID
Conditional Expressions
Use Python conditionals:
"enabled" if active else "disabled"
width if width > 0 else "auto"
Advanced Usage
Multiple Subscriptions
You can subscribe to multiple properties of the same object. Each subscription operates independently with its own update frequency:
// Example: Subscribe to multiple properties with different frequencies
// Fast updates for animation properties (16ms = ~60fps)
position.x // updateFrequencyMs: 16
// Slower updates for static properties (1000ms = 1fps)
description // updateFrequencyMs: 1000
// From ObjectSubscription.vue:80
const subscriptions = useStorage<PropertySubscriptionConfig[]>(storageKey, []);
// Storage format:
[
{
property: "width",
options: { updateFrequencyMs: 50 }
},
{
property: "object.description",
options: { updateFrequencyMs: 1000 }
}
]
Visibility Optimization
The plugin automatically pauses subscriptions when they’re not visible in the viewport, optimizing performance for large numbers of subscriptions.
// From PropertySubscription.vue:52
useSubscriptionVisibility(row, subscription);