The Larvitar Store

The Larvitar Store is a centralized data configuration store that manages the state and settings required for the application. It keeps track of information related to tools, series, viewports, and other imaging-related data, enabling dynamic interaction with the viewer.

Core Responsibilities

The Larvitar Store serves several key purposes:

1. Tools Management:

   • Stores the currently active tools for the left and right mouse buttons.
   • Allows dynamic switching and resetting of tools.

2. Series Management: Tracks series data, including:

   • imageIds: Array of image identifiers for each series.
   • cached: Indicates whether each image in the series has been cached.
   • progress: Tracks the loading progress of the series.
   • elementId: HTML element ID where the series is rendered.

3. Viewport Management: Keeps viewport-specific data, such as:

   • Slice and time positions (sliceId, timeId).
   • Pixel spacing, dimensions, and modality.
   • Viewer settings like zoom, rotation, and translation.

4. Error and Logging: Captures errors and logs them for debugging purposes.

Store Structure

The store is defined by the Store type and includes the following key properties:

Property	Type	Description
colormapId	string	Current colormap identifier (e.g., "gray").
errorLog	string	Error log for debugging.
leftActiveTool	string (optional)	Active tool for the left mouse button.
rightActiveTool	string (optional)	Active tool for the right mouse button.
series	{ [uniqueUID: string]: StoreSeries }	Object mapping uniqueUID to series-specific data.
viewports	{ [key: string]: StoreViewport }	Object mapping viewport IDs to viewport-specific data.

The StoreSeries type includes the following key properties:

Property	Type	Description
imageIds	string	Array of imageIds for the series.
cached	{ [imageId: string]: boolean }	Tracks whether each imageId in the series has been cached or not.

The StoreViewport type includes the following key properties:

Property	Type	Description
loading	number	Caching progress of the series from 0% to 100 %, initialized to null.
ready	boolean	True when the viewport is ready and imageId has been rendered.
uniqueUID	string?	Unique identifier for the series.
modality	string	Modality of the image (e.g., "CT").
isColor	boolean	True if the image is in color.
isMultiframe	boolean	True if the image is multiframe.
isTimeserie	boolean	True if the image is a timeserie.
isDSAEnabled	boolean	True if DSA is enabled.
isPDF	boolean	True if the image is a PDF.
imageId	string	Identifier for the image.
rows	number	Rows in the image.
cols	number	Columns in the image.
spacing_x	number	Spacing in the x direction.
spacing_y	number	Spacing in the y direction.
thickness	number	Slice thickness.
numberOfSlices	number?	Number of slices in the image.
numberOfFrames	number?	Number of frames in the image.
minPixelValue	number	Minimum pixel value.
maxPixelValue	number	Maximum pixel value.
sliceId	number	Slice index identifier of the rendered image.
minSliceId	number	Minimum slice index.
maxSliceId	number	Maximum slice index.
pendingSliceId	number?	Pending slice index to be rendered.
timeId	number	Time index identifier, for timeseries.
timeIndex	number?	Time index, for timeseries.
minTimeId	number	Minimum time index, for timeseries.
maxTimeId	number	Maximum time index, for timeseries.
timeIds	number[]	Array of time index identifiers, for timeseries.
timestamp	number	Timestamp of the image, for timeseries.
timestamps	number[]	Array of image timestamps, for timeseries.
numberOfTemporalPositions	number?	Number of temporal positions, for timeseries.
dsa	boolean	True if DSA is enabled.
pixelShift	number[]	Pixel shift for the image in DSA mode.
waveform	boolean	True if the image has waveform data, for ecg
viewport	viewportType	Type of the viewport.

The Viewport type includes the following key properties:

Property	Type	Description
scale	number	Current scale factor for the viewport.
rotation	number	Current rotation for the viewport.
translation	{x:number, y:number}	Current translation for the viewport.
voi	{windowCenter:number, windowWidth:number}	Current windowing settings for the viewport.
default	viewportType	Default viewport settings.

Initialization

The store must be initialized before use:

import { store } from 'larvitar';
store.initialize();

Viewport Management

A Viewport is a window that displays an image. The store manages viewport-specific data, such as the slice and time positions, pixel spacing, dimensions, and modality. It also stores viewer settings like zoom, rotation, and translation.

To add a viewport to the store, use the addViewport function with the HTML element ID where the viewport is rendered:

import { store } from 'larvitar';
store.addViewport(elementId);

To get the viewport data for a specific element ID, use the get function with the viewport key:

import { store } from 'larvitar';
const viewport = store.get(["viewports", elementId]);

To delete a viewport from the store, use the deleteViewport function with the viewport key:

import { store } from 'larvitar';
store.deleteViewport(elementId);

Series Management

The store tracks series data, including image identifiers, caching status, and loading progress.

To add a set of imageIds to the store, use the addImageIds function with the uniqueUID and imageIds:

import { store } from 'larvitar';
store.addImageIds(uniqueUID, imageIds);

To remove set of imageIds from the store, use the removeImageIds function with the uniqueUID:

import { store } from 'larvitar';
store.removeImageIds(uniqueUID);

To remove all imageIds from the store, use the resetImageIds function:

import { store } from 'larvitar';
store.resetImageIds();

Useful functions

The store provides several utility functions for managing data:

Function	Parameters	Description
setSliceId	elementId, imageIndex	Sets the slice ID for the viewport identified by elementId.
setPendingSliceId	elementId, timeIndex	Sets the pending slice ID for the viewport identified by elementId.
setMaxSliceId	elementId, imageIndex	Sets the max Slice ID for the viewport identified by elementId.
setTimeId	elementId, timeIndex	Sets the time ID for the viewport identified by elementId.
setDSAEnabled	elementId, enabled	Sets the DSA mode for the viewport identified by elementId.
setDSAPixelShift	elementId, pixelShift	Sets the DSA pixel shift for the viewport identified by elementId.
ResetActiveTools	elementId	Resets the active tools.