问水在流动图的透明部分three.js上

EN

    //Creating a texture loader
    var textureLoader = new THREE.TextureLoader();
    let s = 1;

    //DisplacementMap
    const disMap = textureLoader.load('Assets/Textures/heightmap1.jpg')
    disMap.wrapS = disMap.wrapT = THREE.RepeatWrapping;
    disMap.repeat.set(s, s);
    
    //The plane
    var planeGeometry = new THREE.PlaneBufferGeometry(5000, 5000);
    var planeMaterial = new THREE.MeshStandardMaterial({
        color: 0x90EE90,
        displacementMap: disMap,
        displacementScale: 2
    });
    var plane = new THREE.Mesh(planeGeometry, planeMaterial);

    scene.add(plane);

    //The flowmap and the river plane
    const flowMap = textureLoader.load('Assets/Textures/flowmap1.png')
    const river1Geo = new THREE.PlaneGeometry(5000, 5000)

    //The water itself
    const water = new THREE.Water(river1Geo, {
        scale: .1,
        textureWidth: 512,
        textureHeight: 512,
        flowSpeed: 0.04,
        reflectivity: 0.35,
        flowMap: flowMap,
        color: 0x87CEEB
    });
    
    //Positioning and stuff.
    water.position.z = 20;
    water.rotation.x = Math.PI*2;
    scene.add(water);