chore(TS): BaseBrush abstract methods

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## [next]
 
+- chore(TS): BaseBrush abstract methods [#8428](https://github.com/fabricjs/fabric.js/pull/8428)
 - feat(): Add `createObjectDefaultControls` and `createTextboxDefaultControls` to create copies of control sets. [#8415](https://github.com/fabricjs/fabric.js/pull/8415)
 - fix(PatternBrush): `getPatternSrc`, rm `getPatternSrcFunction` [#8468](https://github.com/fabricjs/fabric.js/pull/8468)
 - chore(TS): more FabricObject typing [#8405](https://github.com/fabricjs/fabric.js/pull/8405)

src/brushes/base_brush.class.ts

@@ -1,9 +1,12 @@
 import { fabric } from '../../HEADER';
 import { Color } from '../color';
-import { Point } from '../point.class';
+import type { Point } from '../point.class';
+import { TEvent } from '../EventTypeDefs';
 import type { Shadow } from '../shadow.class';
 import { Canvas } from '../__types__';
 
+type TBrushEventData = TEvent & { pointer: Point };
+
 /**
  * @see {@link http://fabricjs.com/freedrawing|Freedrawing demo}
  */
@@ -76,6 +79,14 @@ export abstract class BaseBrush {
     this.canvas = canvas;
   }
 
+  abstract _render(): void;
+  abstract onMouseDown(pointer: Point, ev: TBrushEventData): void;
+  abstract onMouseMove(pointer: Point, ev: TBrushEventData): void;
+  /**
+   * @returns true if brush should continue blocking interaction
+   */
+  abstract onMouseUp(ev: TBrushEventData): boolean | void;
+
   /**
    * Sets brush styles
    * @private
@@ -101,6 +112,11 @@ export abstract class BaseBrush {
     ctx.transform(v[0], v[1], v[2], v[3], v[4], v[5]);
   }
 
+  protected needsFullRender() {
+    const color = new Color(this.color);
+    return color.getAlpha() < 1 || !!this.shadow;
+  }
+
   /**
    * Sets brush shadow styles
    * @private
@@ -121,11 +137,6 @@ export abstract class BaseBrush {
     ctx.shadowOffsetY = shadow.offsetY * zoom;
   }
 
-  protected needsFullRender() {
-    const color = new Color(this.color);
-    return color.getAlpha() < 1 || !!this.shadow;
-  }
-
   /**
    * Removes brush shadow styles
    * @private