飞线，光照

src/Obj/Materail/PolylineFlowMultMaterialProperty.js

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+/*
+ * @Description: 流动线
+ */
+function PolylineFlowMult() {
+  class PolylineFlowMultMaterialProperty {
+    constructor(options) {
+      this._definitionChanged = new Cesium.Event();
+      this._color = undefined;
+      this._speed = undefined;
+      this.color = new Cesium.Color.fromCssColorString(options.color || "rgba(255,255,255,1)");
+      this.speed = options.speed || 0.1;//速度
+      this.lineBackAlpha = options.lineBackAlpha || 0.05;
+    }
+
+    get isConstant() {
+      return false;
+    }
+
+    get definitionChanged() {
+      return this._definitionChanged;
+    }
+
+    getType(time) {
+      return Cesium.Material.PolylineFlowMultMaterialType;
+    }
+
+    getValue(time, result) {
+      if (!Cesium.defined(result)) {
+        result = {};
+      }
+
+      result.color = Cesium.Property.getValueOrDefault(
+        this._color,
+        time,
+        Cesium.Color.RED,
+        result.color
+      );
+      result.speed = Cesium.Property.getValueOrDefault(
+        this._speed,
+        time,
+        10,
+        result.speed
+      );
+      result.lineBackAlpha = this.lineBackAlpha;
+      result.frameNumber = Cesium.getTimestamp();
+      return result;
+    }
+
+    equals(other) {
+      return (
+        this === other ||
+        (other instanceof PolylineFlowMultMaterialProperty &&
+          Cesium.Property.equals(this._color, other._color) &&
+          Cesium.Property.equals(this._speed, other.speed) &&
+          Cesium.Property.equals(this.lineBackAlpha, other.lineBackAlpha))
+      );
+    }
+  }
+
+  Object.defineProperties(PolylineFlowMultMaterialProperty.prototype, {
+    color: Cesium.createPropertyDescriptor("color"),
+    speed: Cesium.createPropertyDescriptor("speed"),
+    transparency: Cesium.createPropertyDescriptor("lineBackAlpha"),
+  });
+
+  Cesium.PolylineFlowMultMaterialProperty = PolylineFlowMultMaterialProperty;
+  Cesium.Material.PolylineFlowMultMaterialProperty = "PolylineFlowMultMaterialProperty";
+  Cesium.Material.PolylineFlowMultMaterialType = "PolylineFlowMultMaterialType";
+  Cesium.Material.PolylineFlowMaterialSource = `
+      uniform vec4 color;
+      uniform float speed;
+      uniform float lineBackAlpha;
+
+      czm_material czm_getMaterial(czm_materialInput materialInput)
+        {
+            czm_material material = czm_getDefaultMaterial(materialInput);
+            vec2 st = materialInput.st;
+
+            // 基础时间轴（控制主光带）
+            float baseTime = fract(czm_frameNumber * speed / 60.0) * 1.1;
+
+            // 高频时间轴（控制高光点）
+            float highlightTime = fract(czm_frameNumber * speed * 3.0 / 60.0);
+            float highlightSpacing = 0.3; // 高光点间隔
+
+            // 主光带透明度计算
+            float mainAlpha = smoothstep(baseTime-0.1, baseTime, st.s) * step(-baseTime, -st.s);
+
+            // 多高光点计算（3个周期性光斑）
+            float highlight1 = smoothstep(highlightTime-0.05, highlightTime, st.s) *
+                              step(-highlightTime, -st.s) *
+                              (1.0 - smoothstep(0.0, highlightSpacing, abs(st.s - highlightTime)));
+
+            float highlight2 = smoothstep(highlightTime+highlightSpacing-0.05,
+                                        highlightTime+highlightSpacing, st.s) *
+                              step(-(highlightTime+highlightSpacing), -st.s) *
+                              (1.0 - smoothstep(0.0, highlightSpacing, abs(st.s - (highlightTime+highlightSpacing))));
+
+            float highlight3 = smoothstep(highlightTime+2.0*highlightSpacing-0.05,
+                                        highlightTime+2.0*highlightSpacing, st.s) *
+                              step(-(highlightTime+2.0*highlightSpacing), -st.s) *
+                              (1.0 - smoothstep(0.0, highlightSpacing, abs(st.s - (highlightTime+2.0*highlightSpacing))));
+
+            // 合并效果
+            // material.alpha = mainAlpha * 0.7 +
+            //                 (highlight1 + highlight2 + highlight3) * 0.5 +
+            //                 lineBackAlpha;
+            material.alpha = (highlight1 + highlight2 + highlight3) * 0.5 +
+                            lineBackAlpha;
+            material.diffuse = color.rgb; // 高光区变亮
+            return material;
+        }
+       `;
+
+  Cesium.Material._materialCache.addMaterial(
+    Cesium.Material.PolylineFlowMultMaterialType,
+    {
+      fabric: {
+        type: Cesium.Material.PolylineFlowMultMaterialType,
+        uniforms: {
+          color: new Cesium.Color(1.0, 1.0, 1.0, 1.0),
+          speed: 0.1,
+          lineBackAlpha: 0.05,
+        },
+        source: Cesium.Material.PolylineFlowMaterialSource,
+      },
+      translucent: function (material) {
+        return true;
+      },
+    }
+  );
+}
+
+export { PolylineFlowMult }