1.下雪粒子效果启动后，新增在模型上添加积雪效果；

src/components/CesiumMap/mixins/useWeatherParticle/index.js

@@ -31,6 +31,8 @@ export const useWeatherParticle = (viewer) => {
     weather = new SnowEffect(_viewer, {
       snowSize: 0.02, // ❄️大小，最好小于0.02
       snowSpeed: 60.0, // 速度
+      isCover: true, // 是否显示积雪覆盖效果
+      coverage: 0.3, // 积雪覆盖（混色）占比
     });
     weather.show(true);
   };

src/components/CesiumMap/mixins/useWeatherParticle/snow.js

@@ -13,6 +13,9 @@ class SnowEffect {
     options = options || {};
     this.snowSize = Cesium.defaultValue(options.snowSize, 0.02); // ❄️大小，最好小于0.02
     this.snowSpeed = Cesium.defaultValue(options.snowSpeed, 60.0); // 速度
+    // 积雪效果
+    this.isCover = Cesium.defaultValue(options.isCover, false); // 是否显示积雪覆盖效果
+    this.coverage = Cesium.defaultValue(options.coverage, 0.3); // 积雪覆盖（混色）占比
     this.viewer = viewer;
     this.init();
   }
@@ -31,6 +34,27 @@ class SnowEffect {
       },
     });
     this.viewer.scene.postProcessStages.add(this.snowStage);
+    if(this.isCover) {
+      const coverShader = new Cesium.CustomShader({
+        uniforms: {
+          u_lightColor: {
+            type: Cesium.UniformType.VEC3,
+            value: new Cesium.Cartesian3(1, 1, 1),
+          },
+          u_snowAlpha: {
+            type: Cesium.UniformType.FLOAT,
+            value: this.coverage,
+          },
+        },
+        fragmentShaderText: this.cover()
+      })
+      for (let index = 0; index < this.viewer.scene.primitives.length; index++) {
+        const primitive = this.viewer.scene.primitives.get(index);
+        if(primitive instanceof Cesium.Cesium3DTileset) {
+          primitive.customShader = coverShader;
+        }
+      }
+    }
   }
 
   destroy() {
@@ -43,6 +67,19 @@ class SnowEffect {
     }
     delete this.snowSize;
     delete this.snowSpeed;
+    
+    // 销毁积雪效果
+    if(this.isCover === undefined) return;
+    if(this.isCover) {
+      for (let index = 0; index < this.viewer.scene.primitives.length; index++) {
+        const primitive = this.viewer.scene.primitives.get(index);
+        if(primitive instanceof Cesium.Cesium3DTileset) {
+          primitive.customShader = undefined;
+        }
+      }
+      delete this.isCover;
+      delete this.coverStage;
+    }
   }
   show(visible) {
     this.snowStage.enabled = visible;
@@ -82,5 +119,71 @@ class SnowEffect {
               }\n\
               ";
   }
+
+  cover() {
+    return `
+      #define MAX_RADIUS 2
+      // Set to 1 to hash twice. Slower, but less patterns.
+      #define DOUBLE_HASH 0
+      // Hash functions shamefully stolen from:
+      // https://www.shadertoy.com/view/4djSRW
+      #define HASHSCALE1 .1031
+      #define HASHSCALE3 vec3(.1031, .1030, .0973)
+      float hash12(vec2 p)
+      {
+          vec3 p3  = fract(vec3(p.xyx) * HASHSCALE1);
+          p3 += dot(p3, p3.yzx + 19.19);
+          return fract((p3.x + p3.y) * p3.z);
+      }
+      vec2 hash22(vec2 p)
+      {
+          vec3 p3 = fract(vec3(p.xyx) * HASHSCALE3);
+          p3 += dot(p3, p3.yzx+19.19);
+          return fract((p3.xx+p3.yz)*p3.zy);
+
+      }
+      void fragmentMain(FragmentInput fsInput, inout czm_modelMaterial material) {
+          vec3 positionEC = fsInput.attributes.positionEC;
+          vec3 positionMC = fsInput.attributes.positionMC;
+          vec2 uv = fsInput.attributes.texCoord_0 * 500.;
+          vec3 pos_dx = dFdx(positionEC);
+          vec3 pos_dy = dFdy(positionEC);
+          vec3 normalEC = normalize(cross(pos_dx, pos_dy));
+          vec4 positionWC = normalize(czm_inverseView * vec4(positionEC,1.0));
+          vec3 normalWC = normalize(czm_inverseViewRotation * normalEC);
+          float time = czm_frameNumber / 60.0;
+          vec2 p0 = floor(uv);
+          vec2 circles = vec2(0.);
+          for (int j = -MAX_RADIUS; j <= MAX_RADIUS; ++j)
+          {
+              for (int i = -MAX_RADIUS; i <= MAX_RADIUS; ++i)
+              {
+                  vec2 pi = p0 + vec2(i, j);
+                  #if DOUBLE_HASH
+                  vec2 hsh = hash22(pi);
+                  #else
+                  vec2 hsh = pi;
+                  #endif
+                  vec2 p = pi + hash22(hsh);
+
+                  float t = fract(0.3*time + hash12(hsh));
+                  vec2 v = p - uv;
+                  float d = length(v) - (float(MAX_RADIUS) + 1.)*t;
+
+                  float h = 1e-3;
+                  float d1 = d - h;
+                  float d2 = d + h;
+                  float p1 = sin(31.*d1) * smoothstep(-0.6, -0.3, d1) * smoothstep(0., -0.3, d1);
+                  float p2 = sin(31.*d2) * smoothstep(-0.6, -0.3, d2) * smoothstep(0., -0.3, d2);
+                  circles += 0.5 * normalize(v) * ((p2 - p1) / (2. * h) * (1. - t) * (1. - t));
+              }
+          }
+          circles /= float((MAX_RADIUS*2+1)*(MAX_RADIUS*2+1));
+          vec3 n = vec3(circles, sqrt(1. - dot(circles, circles)));
+          material.diffuse = mix(material.diffuse, vec3(1.0) , u_snowAlpha * smoothstep(0., .5, dot(positionWC.xyz, normalWC)));
+          material.diffuse *= min(max(0.0, dot(normalEC, czm_sunDirectionEC) * 1.0) + u_lightColor, 1.0);
+      }
+    `;
+  }
 }
 export default SnowEffect;

src/views/systemTemplate/forestFire/index.vue

@@ -25,6 +25,10 @@ const options = ref({
   },
   ditu: 'tianditu', // 底图选择
   isTerrainProvider: true, // 启用地形
+  modelList: [
+    '/model/hu_ma_shan/tileset.json',
+    '/model/yi_liu/tileset.json'
+  ], // 测试模型列表
 })
 const showProperty = ref(false); // 控制属性面板的显示与隐藏
 const propertyData = ref([])