sprotty/src/features/edge-layout/model.ts

A next-gen framework for graphical views

/********************************************************************************
 * Copyright (c) 2017-2024 TypeFox and others.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the Eclipse
 * Public License v. 2.0 are satisfied: GNU General Public License, version 2
 * with the GNU Classpath Exception which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 ********************************************************************************/

import type { EdgePlacement as EdgePlacementSchema } from 'sprotty-protocol/lib/model';
import { SModelElementImpl, SChildElementImpl } from '../../base/model/smodel';
import { InternalBoundsAware, isBoundsAware } from '../bounds/model';
import { SRoutableElementImpl } from '../routing/model';

export const edgeLayoutFeature = Symbol('edgeLayout');

/**
 * @deprecated Use EdgeLayoutable from sprotty-protocol instead
 * Feature extension interface for {@link edgeLayoutFeature}.
 */
export interface EdgeLayoutable {
    edgePlacement: EdgePlacementSchema
}

export function isEdgeLayoutable<T extends SModelElementImpl>(element: T): element is T & SChildElementImpl & InternalBoundsAware & EdgeLayoutable {
    return element instanceof SChildElementImpl
        && element.parent instanceof SRoutableElementImpl
        && isBoundsAware(element)
        && element.hasFeature(edgeLayoutFeature);
}

export function checkEdgePlacement(element: SChildElementImpl): element is SChildElementImpl & EdgeLayoutable {
    return 'edgePlacement' in element;
}

/**
 * @deprecated Use EdgeSide from sprotty-protocol instead
 */
export type EdgeSide = 'left' | 'right' | 'top' | 'bottom' | 'on';

/**
 * @deprecated Use EdgePlacement from sprotty-protocol instead
 */
export class EdgePlacement extends Object {
    /**
     * true, if the label should be rotated to touch the edge tangentially
     */
    rotate: boolean;

    /**
     * where is the label relative to the line's direction
     */
    side: EdgeSide;

    /**
     * between 0 (source anchor) and 1 (target anchor)
     */
    position: number;

    /**
     * space between label and edge/connected nodes
     */
    offset: number;

    /**
     * where should the label be moved when move feature is enabled.
     * 'edge' means the label is moved along the edge, 'free' means the label is moved freely, 'none' means the label is not moved.
     * Default is 'edge'.
     */
    moveMode?: 'edge' | 'free' | 'none';

}

export const DEFAULT_EDGE_PLACEMENT: EdgePlacementSchema = {
    rotate: true,
    side: 'top',
    position: 0.5,
    offset: 7
};