飞线，光照

src/Obj/Materail/LineTextureMaterialProperty.js

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+/*
+ * @Description: 流动线
+ */
+function LineTexture() {
+  class LineTextureMaterialProperty {
+    constructor(options) {
+      this._definitionChanged = new Cesium.Event();
+      this._image = undefined;
+      this._color = undefined;
+      this._imageW = undefined;
+      this.image = options.image || "";
+      this.color = new Cesium.Color.fromCssColorString(options.color || "rgba(255,255,255,1)");
+      this.imageW = options.imageW || 1;
+    }
+
+    get isConstant() {
+      return false;
+    }
+
+    get definitionChanged() {
+      return this._definitionChanged;
+    }
+
+    getType(time) {
+      return Cesium.Material.LineTextureMaterialType;
+    }
+
+    getValue(time, result) {
+      if (!Cesium.defined(result)) {
+        result = {};
+      }
+      result.image = Cesium.Property.getValueOrDefault(
+        this._image,
+        time,
+        "",
+        result.image
+      );
+      result.color = Cesium.Property.getValueOrDefault(
+        this._color,
+        time,
+        Cesium.Color.RED,
+        result.color
+      );
+      result.imageW = Cesium.Property.getValueOrDefault(
+        this._imageW,
+        time,
+        1,
+        result.imageW
+      );
+      return result;
+    }
+
+    equals(other) {
+      return (
+        this === other ||
+        (other instanceof LineTextureMaterialProperty &&
+          Cesium.Property.equals(this._image, other._image) &&
+          Cesium.Property.equals(this._color, other._color) &&
+          Cesium.Property.equals(this._imageW, other._imageW))
+      );
+    }
+  }
+
+  Object.defineProperties(LineTextureMaterialProperty.prototype, {
+    image: Cesium.createPropertyDescriptor("image"),
+    color: Cesium.createPropertyDescriptor("color"),
+    imageW: Cesium.createPropertyDescriptor("imageW"),
+  });
+
+  Cesium.LineTextureMaterialProperty = LineTextureMaterialProperty;
+  Cesium.Material.LineTextureMaterialProperty = "LineTextureMaterialProperty";
+  Cesium.Material.LineTextureMaterialType = "LineTextureMaterialType";
+  Cesium.Material.LineTextureMaterialSource = `
+        #extension GL_OES_standard_derivatives : enable
+        czm_material czm_getMaterial(czm_materialInput materialInput)
+        {
+            czm_material m = czm_getDefaultMaterial(materialInput);
+
+
+            vec2 st = materialInput.st * vec2(494/172, 1.0); // 横向重复两次
+            vec2 uv = vec2(fract(st.s + uTime*0.1), st.t);
+            // uv.y = mix(uv.y, 1.0-uv.y, step(0.5, fract(uTime))); // 周期性反转Y轴
+            vec4 tex = texture(image, uv);
+            m.diffuse =(tex.rgb+color.rgb)/2.0;
+            m.alpha = tex.a * (1.0 - fract(st.t)) * color.a; // 顶部渐隐
+
+            return m;
+        }
+       `;
+  Cesium.Material._materialCache.addMaterial(
+    Cesium.Material.LineTextureMaterialType,
+    {
+      fabric: {
+        type: Cesium.Material.LineTextureMaterialType,
+        uniforms: {
+          color: new Cesium.Color(1.0, 1.0, 1.0, 1.0),
+          image: '',
+          imageW: 1,
+          uTime: 1
+        },
+        source: Cesium.Material.LineTextureMaterialSource,
+      },
+      translucent: function (material) {
+        return true;
+      },
+    }
+  );
+}
+
+export { LineTexture }