maxGraph · tbouffard · Jan 7, 2025 · Jan 6, 2025 · Jan 6, 2025
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
@@ -159,6 +159,7 @@ export { default as ObjectIdentity } from './util/ObjectIdentity';
 export { default as Point } from './view/geometry/Point';
 export { default as Rectangle } from './view/geometry/Rectangle';
 
+export * from './view/style/config';
 export { default as EdgeStyle } from './view/style/EdgeStyle';
 export { default as Perimeter } from './view/style/Perimeter';
 export { default as StyleRegistry } from './view/style/StyleRegistry';

diff --git a/packages/core/src/util/Constants.ts b/packages/core/src/util/Constants.ts
@@ -362,8 +362,7 @@ export const DEFAULT_MARKERSIZE = 6;
 export const DEFAULT_IMAGESIZE = 24;
 
 /**
- * Defines the length of the horizontal segment of an `Entity Relation`.
- * This can be overridden using {@link CellStateStyle.segment} style.
+ * Default value of {@link EntityRelationConnectorConfig.segment}.
  */
 export const ENTITY_SEGMENT = 30;
 

diff --git a/packages/core/src/view/style/config.ts b/packages/core/src/view/style/config.ts
@@ -0,0 +1,45 @@
+/*
+Copyright 2025-present The maxGraph project Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { ENTITY_SEGMENT } from '../../util/Constants';
+
+/**
+ * Configure the `Entity Relation connector` defaults for maxGraph.
+ *
+ * @experimental subject to change or removal. maxGraph's global configuration may be modified in the future without prior notice.
+ * @since 0.15.0
+ * @category Configuration
+ */
+export const EntityRelationConnectorConfig = {
+  /**
+   * Defines the length of the horizontal segment of an `Entity Relation`.
+   * This can be overridden using {@link CellStateStyle.segment} style.
+   * @default {@link ENTITY_SEGMENT}
+   */
+  segment: ENTITY_SEGMENT,
+};
+
+/**
+ * Resets {@link EntityRelationConnectorConfig} to default values.
+ *
+ * @experimental Subject to change or removal. maxGraph's global configuration may be modified in the future without prior notice.
+ * @since 0.15.0
+ * @category Configuration
+ */
+export const resetEntityRelationConnectorConfig = (): void => {
+  // implement the reset manually as there are a few properties for now
+  EntityRelationConnectorConfig.segment = ENTITY_SEGMENT;
+};
diff --git a/packages/core/src/view/style/edge/EntityRelation.ts b/packages/core/src/view/style/edge/EntityRelation.ts
@@ -19,11 +19,10 @@ limitations under the License.
 import CellState from '../../cell/CellState';
 import Geometry from '../../geometry/Geometry';
 import Point from '../../geometry/Point';
-import { DIRECTION_MASK, ENTITY_SEGMENT } from '../../../util/Constants';
+import { DIRECTION_MASK } from '../../../util/Constants';
 import { getPortConstraints } from '../../../util/mathUtils';
-import { getValue } from '../../../util/Utils';
-
 import type { EdgeStyleFunction } from '../../../types';
+import { EntityRelationConnectorConfig } from '../config';
 
 export const EntityRelation: EdgeStyleFunction = (
   state: CellState,
@@ -33,7 +32,8 @@ export const EntityRelation: EdgeStyleFunction = (
   result: Point[]
 ) => {
   const { view } = state;
-  const segment = getValue(state.style, 'segment', ENTITY_SEGMENT) * view.scale;
+  const segment =
+    (state.style?.segment ?? EntityRelationConnectorConfig.segment) * view.scale;
 
   const pts = state.absolutePoints;
   const p0 = pts[0];

diff --git a/packages/html/.storybook/preview.ts b/packages/html/.storybook/preview.ts
@@ -3,6 +3,7 @@ import {
   GlobalConfig,
   NoOpLogger,
   resetEdgeHandlerConfig,
+  resetEntityRelationConnectorConfig,
   resetHandleConfig,
   resetStyleDefaultsConfig,
   resetVertexHandlerConfig,
@@ -19,6 +20,7 @@ const resetMaxGraphConfigs = (): void => {
   GlobalConfig.logger = defaultLogger;
 
   resetEdgeHandlerConfig();
+  resetEntityRelationConnectorConfig();
   resetHandleConfig();
   resetStyleDefaultsConfig();
   resetVertexHandlerConfig();

diff --git a/packages/html/stories/Folding.stories.ts b/packages/html/stories/Folding.stories.ts
@@ -15,7 +15,14 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import { constants, EdgeStyle, Graph, LayoutManager, StackLayout } from '@maxgraph/core';
+import {
+  constants,
+  EdgeStyle,
+  EntityRelationConnectorConfig,
+  Graph,
+  LayoutManager,
+  StackLayout,
+} from '@maxgraph/core';
 import { globalTypes, globalValues } from './shared/args.js';
 import {
   configureExpandedAndCollapsedImages,
@@ -37,9 +44,8 @@ const Template = ({ label, ...args }: Record<string, string>) => {
   configureImagesBasePath();
   const container = createGraphContainer(args);
 
-  // TODO Allow overriding constants. See https://github.com/maxGraph/maxGraph/issues/192
-  // Enables crisp rendering of rectangles in SVG
-  // constants.ENTITY_SEGMENT = 20;
+  // Override default values
+  EntityRelationConnectorConfig.segment = 20;
 
   // Creates the graph inside the given container
   const graph = new Graph(container);

diff --git a/packages/website/docs/usage/global-configuration.md b/packages/website/docs/usage/global-configuration.md
@@ -14,6 +14,7 @@ The following objects can be used to configure `maxGraph` globally:
 
   - `Client`: this is the historical entry point for global configuration, coming from the `mxGraph` library.
   - `EdgeHandlerConfig` (since 0.14.0): for `EdgeHandler` (including subclasses).
+  - `EntityRelationConnectorConfig` (since 0.15.0): for the `EntityRelation` Connector/EdgeStyle.
   - `GlobalConfig` (since 0.11.0): for shared resources (logger).
   - `HandleConfig` (since 0.14.0): for shared handle configurations.
   - `StencilShapeConfig` (since 0.11.0): for stencil shapes.
@@ -23,6 +24,7 @@ The following objects can be used to configure `maxGraph` globally:
 Some functions are provided to reset the global configuration to the default values. For example:
 
   - `resetEdgeHandlerConfig` (since 0.14.0)
+  - `resetEntityRelationConnectorConfig` (since 0.15.0)
   - `resetHandleConfig` (since 0.14.0)
   - `resetStyleDefaultsConfig` (since 0.14.0)
   - `resetVertexHandlerConfig` (since 0.14.0)