Matter Physics Drag Filter

class Example extends Phaser.Scene
{
    preload ()
    {
        this.load.setBaseURL('https://cdn.phaserfiles.com/v410');
        this.load.image('block', 'assets/sprites/block.png');
        this.load.image('mushroom', 'assets/sprites/mushroom2.png');
    }

    create ()
    {
        this.matter.world.setBounds();

        //  Add a few blocks, you can drag all of these with the pointer

        const canDrag = this.matter.world.nextGroup();

        this.matter.add.image(100, 100, 'block', null, { chamfer: 16 }).setBounce(0.9).setCollisionGroup(canDrag);
        this.matter.add.image(300, 100, 'block', null, { chamfer: 16 }).setBounce(0.9).setCollisionGroup(canDrag);
        this.matter.add.image(600, 100, 'block', null, { chamfer: 16 }).setBounce(0.9).setCollisionGroup(canDrag);

        //  Add some mushrooms, you cannot drag these

        const noDrag = this.matter.world.nextGroup();

        this.matter.add.image(200, 100, 'mushroom', null, { chamfer: 16 }).setBounce(0.9).setCollisionGroup(noDrag);
        this.matter.add.image(400, 100, 'mushroom', null, { chamfer: 16 }).setBounce(0.9).setCollisionGroup(noDrag);
        this.matter.add.image(500, 100, 'mushroom', null, { chamfer: 16 }).setBounce(0.9).setCollisionGroup(noDrag);

        //  Our constraint

        this.matter.add.mouseSpring({ length: 1, stiffness: 0.6, collisionFilter: { group: canDrag } });
    }
}

const config = {
    scale: { mode: Phaser.Scale.FIT },
    type: Phaser.AUTO,
    width: 800,
    height: 600,
    backgroundColor: '#1b1464',
    parent: 'game-container',
    physics: {
        default: 'matter'
    },
    scene: Example
};

const game = new Phaser.Game(config);