154 lines
3.0 KiB
JavaScript
154 lines
3.0 KiB
JavaScript
/**
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* @author alteredq / http://alteredqualia.com/
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* @author mrdoob / http://mrdoob.com/
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*/
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var _Math = {
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DEG2RAD: Math.PI / 180,
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RAD2DEG: 180 / Math.PI,
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generateUUID: ( function () {
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// http://stackoverflow.com/questions/105034/how-to-create-a-guid-uuid-in-javascript/21963136#21963136
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var lut = [];
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for ( var i = 0; i < 256; i ++ ) {
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lut[ i ] = ( i < 16 ? '0' : '' ) + ( i ).toString( 16 );
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}
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return function generateUUID() {
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var d0 = Math.random() * 0xffffffff | 0;
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var d1 = Math.random() * 0xffffffff | 0;
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var d2 = Math.random() * 0xffffffff | 0;
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var d3 = Math.random() * 0xffffffff | 0;
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var uuid = lut[ d0 & 0xff ] + lut[ d0 >> 8 & 0xff ] + lut[ d0 >> 16 & 0xff ] + lut[ d0 >> 24 & 0xff ] + '-' +
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lut[ d1 & 0xff ] + lut[ d1 >> 8 & 0xff ] + '-' + lut[ d1 >> 16 & 0x0f | 0x40 ] + lut[ d1 >> 24 & 0xff ] + '-' +
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lut[ d2 & 0x3f | 0x80 ] + lut[ d2 >> 8 & 0xff ] + '-' + lut[ d2 >> 16 & 0xff ] + lut[ d2 >> 24 & 0xff ] +
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lut[ d3 & 0xff ] + lut[ d3 >> 8 & 0xff ] + lut[ d3 >> 16 & 0xff ] + lut[ d3 >> 24 & 0xff ];
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// .toUpperCase() here flattens concatenated strings to save heap memory space.
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return uuid.toUpperCase();
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};
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} )(),
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clamp: function ( value, min, max ) {
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return Math.max( min, Math.min( max, value ) );
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},
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// compute euclidian modulo of m % n
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// https://en.wikipedia.org/wiki/Modulo_operation
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euclideanModulo: function ( n, m ) {
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return ( ( n % m ) + m ) % m;
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},
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// Linear mapping from range <a1, a2> to range <b1, b2>
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mapLinear: function ( x, a1, a2, b1, b2 ) {
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return b1 + ( x - a1 ) * ( b2 - b1 ) / ( a2 - a1 );
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},
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// https://en.wikipedia.org/wiki/Linear_interpolation
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lerp: function ( x, y, t ) {
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return ( 1 - t ) * x + t * y;
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},
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// http://en.wikipedia.org/wiki/Smoothstep
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smoothstep: function ( x, min, max ) {
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if ( x <= min ) return 0;
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if ( x >= max ) return 1;
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x = ( x - min ) / ( max - min );
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return x * x * ( 3 - 2 * x );
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},
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smootherstep: function ( x, min, max ) {
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if ( x <= min ) return 0;
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if ( x >= max ) return 1;
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x = ( x - min ) / ( max - min );
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return x * x * x * ( x * ( x * 6 - 15 ) + 10 );
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},
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// Random integer from <low, high> interval
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randInt: function ( low, high ) {
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return low + Math.floor( Math.random() * ( high - low + 1 ) );
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},
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// Random float from <low, high> interval
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randFloat: function ( low, high ) {
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return low + Math.random() * ( high - low );
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},
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// Random float from <-range/2, range/2> interval
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randFloatSpread: function ( range ) {
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return range * ( 0.5 - Math.random() );
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},
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degToRad: function ( degrees ) {
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return degrees * _Math.DEG2RAD;
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},
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radToDeg: function ( radians ) {
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return radians * _Math.RAD2DEG;
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},
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isPowerOfTwo: function ( value ) {
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return ( value & ( value - 1 ) ) === 0 && value !== 0;
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},
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ceilPowerOfTwo: function ( value ) {
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return Math.pow( 2, Math.ceil( Math.log( value ) / Math.LN2 ) );
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},
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floorPowerOfTwo: function ( value ) {
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return Math.pow( 2, Math.floor( Math.log( value ) / Math.LN2 ) );
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}
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};
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export { _Math };
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