import * as Cesium from 'cesium';
/**
 * 定义Cesium材质对象
 */
class ImageTrailMaterial {
    constructor(options = {}) {
        this._definitionChanged = new Cesium.Event();
        this._color = void 0;
        this._colorSubscription = void 0;
        this._speed = void 0;
        this._speedSubscription = void 0;
        this._image = void 0;
        this._imageSubscription = void 0;
        this._repeat = void 0;
        this._repeatSubscription = void 0;
        this.color = options.color || Cesium.Color.fromBytes(0, 0, 255, 255);
        this.speed = options.speed || 1;
        this.image = options.image;
        this.repeat = new Cesium.Cartesian2(
            options.repeat?.x || 1,
            options.repeat?.y || 1,
        );
    }

    get isConstant() {
        return false;
    }

    get definitionChanged() {
        return this._definitionChanged;
    }

    getType() {
        return Cesium.Material.ImageTrailMaterialType;
    }

    getValue(time, result) {
        if (!result) {
            result = {};
        }
        result.color = Cesium.Property.getValueOrUndefined(this._color, time);
        result.image = Cesium.Property.getValueOrUndefined(this._image, time);
        result.repeat = Cesium.Property.getValueOrUndefined(this._repeat, time);
        result.speed = this._speed;
        return result;
    }

    equals(other) {
        return (
            this === other ||
            (other instanceof ImageTrailMaterial &&
                Cesium.Property.equals(this._color, other._color) &&
                Cesium.Property.equals(this._image, other._image) &&
                Cesium.Property.equals(this._repeat, other._repeat) &&
                Cesium.Property.equals(this._speed, other._speed))
        );
    }
}

Object.defineProperties(ImageTrailMaterial.prototype, {
    color: Cesium.createPropertyDescriptor('color'),
    speed: Cesium.createPropertyDescriptor('speed'),
    image: Cesium.createPropertyDescriptor('image'),
    repeat: Cesium.createPropertyDescriptor('repeat'),
});
//材质类型
Cesium.Material.ImageTrailMaterialType = 'PolylineImageTrail';
//添加材质到缓冲区中
Cesium.Material._materialCache.addMaterial(
    Cesium.Material.ImageTrailMaterialType,
    {
        fabric: {
            type: Cesium.Material.ImageTrailMaterialType,
            //uniform变量
            uniforms: {
                color: new Cesium.Color(1.0, 0.0, 0.0, 0.7),
                image: Cesium.Material.DefaultImageId,
                speed: 1,
                repeat: new Cesium.Cartesian2(1, 1),
            },
            //
            source: `
                    uniform sampler2D image; 
                    uniform float speed;
                    uniform vec4 color;
                    uniform vec2 repeat;
                    
                    czm_material czm_getMaterial(czm_materialInput materialInput){
                        czm_material material=czm_getDefaultMaterial(materialInput);
                        vec2 st=repeat * materialInput.st;
                        float time=fract(czm_frameNumber*speed/1000.);
                        vec4 colorImage=texture2D(image,vec2(fract(st.s-time),st.t));
                        material.alpha = colorImage.a * color.a;
                        material.diffuse = (colorImage.rgb+color.rgb)/2.0;
                        return material;
                    }
                    `,
        },
        translucent: function () {
            return true;
        },
    },
);
export default ImageTrailMaterial;

//之前的航线材质编写
// source: `
// uniform sampler2D image;
// uniform float speed;
// uniform vec4 color;
// uniform vec2 repeat;

// czm_material czm_getMaterial(czm_materialInput materialInput){
//     czm_material material=czm_getDefaultMaterial(materialInput);
//     vec2 st=repeat * materialInput.st;
//     float time=fract(czm_frameNumber*speed/1000.);
//     // st.s是横轴方向运动,st.t是纵轴，
//     // vec2(fract(st.s-time),st.t)是横轴按照时间变化而变化，纵轴保持正常不变化
//     vec4 colorImage=texture2D(image,vec2(fract(st.s-time),st.t));
//     vec4 fragColor;
//     fragColor.rgb=color.rgb / 1.0;
//     if(color.a==0.){
//         material.alpha=colorImage.a;
//         material.diffuse=colorImage.rgb;
//     }else{
//         material.alpha=colorImage.a*color.a;
//         material.diffuse=max(color.rgb*material.alpha*3.,color.rgb);
//     }
//     return material;
// }
// `