RenderState
type RenderState = object;
RenderState is the information passed to a panel's onRender function.
To receive updates for specific parts of the RenderState, you must first call the watch function and specify the field name. For example, call watch("currentTime") to receive updates for currentTime.
If a field is missing from the RenderState, it could be because the value hasn't changed since the last onRender call, or you haven't called watch for that field.
Properties
currentFrame?
optional currentFrame: MessageEvent[];
The latest messages for the current render frame. These are new messages since the previous render frame.
didSeek?
optional didSeek: boolean;
True if the data source performed a seek operation. This indicates that some data may have been skipped (never appeared in currentFrame), so the panel should clear any stale state to avoid displaying incorrect data.
allFrames?
optional allFrames: MessageEvent[];
All available messages. Lists all available messages when possible.
Deprecated
Please use PanelExtensionContext.subscribeMessageRange instead.
parameters?
optional parameters: Map<string, ParameterValue>;
A map of current parameter values. Parameters are key/value pairs associated with a data source, and may not be supported by all data sources. For example, ROS 1 live connections support parameters via the parameter server.
sharedPanelState?
optional sharedPanelState: Record<string, unknown>;
Temporary panel state shared between panels of the same type. This can be any data that panel authors wish to share between panels.
variables?
optional variables: Map<string, VariableValue>;
A map of current Studio variables. Variables are key/value pairs that are globally accessible by panels and scripts in the current layout.
topics?
optional topics: Topic[];
A list of available topics. This list includes both subscribed and unsubscribed topics.
currentTime?
optional currentTime: Time;
A timestamp value representing the current playback time.
startTime?
optional startTime: Time;
The starting timestamp of the current data source playback range. For offline files, this value is expected to be present. For live connections, the start time may or may not be present depending on the data source.
endTime?
optional endTime: Time;
The ending timestamp of the current data source playback range. For offline files, this value is expected to be present. For live connections, the end time may or may not be present depending on the data source.
previewTime?
optional previewTime: number;
A value in seconds representing the preview time. Preview time is set when a user hovers over the seek bar or when a panel explicitly sets the preview time. The preview time is a value in seconds within the playback range.
For example, a chart panel might set the preview time when the user hovers over the chart, signaling to other panels where the user is currently hovering and allowing them to render accordingly.
colorScheme?
optional colorScheme: "dark" | "light";
The color scheme currently used throughout the application.
appSettings?
optional appSettings: Map<string, AppSettingValue>;
Application settings. This will only include key/values subscribed to with @PanelExtensionContext.subscribeAppSettings.