Add existing to tracked

node_modules/@cesium/engine/Source/Shaders/BufferPointMaterialFS.glsl

@@ -0,0 +1,28 @@
+in vec4 v_pickColor;
+in vec4 v_color;
+in vec4 v_outlineColor;
+in float v_innerRadiusFrac;
+
+void main()
+{
+    // Distance between fragment and point center, 0 to 0.5.
+    float distanceToCenter = length(gl_PointCoord - vec2(0.5));
+    float delta = fwidth(distanceToCenter);
+
+    float outerLimit = 0.5;
+    float innerLimit = 0.5 * v_innerRadiusFrac;
+
+    float outerAlpha = 1.0 - smoothstep(max(0.0, outerLimit - delta), outerLimit, distanceToCenter);
+    float innerAlpha = 1.0 - smoothstep(innerLimit - delta, innerLimit, distanceToCenter);
+
+    vec4 color = vec4(mix(v_outlineColor.rgb, v_color.rgb, innerAlpha), outerAlpha);
+    color.a *= mix(v_outlineColor.a, v_color.a, innerAlpha);
+
+    if (color.a < 0.005)   // matches 0/255 and 1/255
+    {
+        discard;
+    }
+
+    out_FragColor = czm_gammaCorrect(color);
+    czm_writeLogDepth();
+}