/**
 * A built-in GLSL floating-point constant for <code>pi/2</code>.
 *
 * @alias czm_piOverTwo
 * @glslConstant
 *
 * @see CesiumMath.PI_OVER_TWO
 *
 * @example
 * // GLSL declaration
 * const float czm_piOverTwo = ...;
 *
 * // Example
 * float pi = 2.0 * czm_piOverTwo;
 */
const float czm_piOverTwo = 1.5707963267948966;