jtBaseApp/node_modules/@cesium/engine/Source/Shaders/Builtin/Functions/unpackUint.glsl

/**
 * Unpack unsigned integers of 1-4 bytes. in WebGL 1, there is no uint type,
 * so the return value is an int.
 * <p>
 * There are also precision limitations in WebGL 1. highp int is still limited
 * to 24 bits. Above the value of 2^24 = 16777216, precision loss may occur.
 * </p>
 *
 * @param {float|vec2|vec3|vec4} packed The packed value. For vectors, the components are listed in little-endian order.
 *
 * @return {int} The unpacked value.
 */
 int czm_unpackUint(float packedValue) {
   float rounded = czm_round(packedValue * 255.0);
   return int(rounded);
 }

 int czm_unpackUint(vec2 packedValue) {
   vec2 rounded = czm_round(packedValue * 255.0);
   return int(dot(rounded, vec2(1.0, 256.0)));
 }

 int czm_unpackUint(vec3 packedValue) {
   vec3 rounded = czm_round(packedValue * 255.0);
   return int(dot(rounded, vec3(1.0, 256.0, 65536.0)));
 }

 int czm_unpackUint(vec4 packedValue) {
   vec4 rounded = czm_round(packedValue * 255.0);
   return int(dot(rounded, vec4(1.0, 256.0, 65536.0, 16777216.0)));
 }