import {
DataTexture,
FileLoader,
FloatType,
RedFormat,
MathUtils,
Loader,
UnsignedByteType,
LinearFilter,
HalfFloatType,
DataUtils
} from 'three';
class IESLoader extends Loader {
constructor( manager ) {
super( manager );
this.type = HalfFloatType;
}
_getIESValues( iesLamp, type ) {
const width = 360;
const height = 180;
const size = width * height;
const data = new Array( size );
function interpolateCandelaValues( phi, theta ) {
let phiIndex = 0, thetaIndex = 0;
let startTheta = 0, endTheta = 0, startPhi = 0, endPhi = 0;
for ( let i = 0; i < iesLamp.numHorAngles - 1; ++ i ) { // numHorAngles = horAngles.length-1 because of extra padding, so this wont cause an out of bounds error
if ( theta < iesLamp.horAngles[ i + 1 ] || i == iesLamp.numHorAngles - 2 ) {
thetaIndex = i;
startTheta = iesLamp.horAngles[ i ];
endTheta = iesLamp.horAngles[ i + 1 ];
break;
}
}
for ( let i = 0; i < iesLamp.numVerAngles - 1; ++ i ) {
if ( phi < iesLamp.verAngles[ i + 1 ] || i == iesLamp.numVerAngles - 2 ) {
phiIndex = i;
startPhi = iesLamp.verAngles[ i ];
endPhi = iesLamp.verAngles[ i + 1 ];
break;
}
}
const deltaTheta = endTheta - startTheta;
const deltaPhi = endPhi - startPhi;
if ( deltaPhi === 0 ) // Outside range
return 0;
const t1 = deltaTheta === 0 ? 0 : ( theta - startTheta ) / deltaTheta;
const t2 = ( phi - startPhi ) / deltaPhi;
const nextThetaIndex = deltaTheta === 0 ? thetaIndex : thetaIndex + 1;
const v1 = MathUtils.lerp( iesLamp.candelaValues[ thetaIndex ][ phiIndex ], iesLamp.candelaValues[ nextThetaIndex ][ phiIndex ], t1 );
const v2 = MathUtils.lerp( iesLamp.candelaValues[ thetaIndex ][ phiIndex + 1 ], iesLamp.candelaValues[ nextThetaIndex ][ phiIndex + 1 ], t1 );
const v = MathUtils.lerp( v1, v2, t2 );
return v;
}
const startTheta = iesLamp.horAngles[ 0 ], endTheta = iesLamp.horAngles[ iesLamp.numHorAngles - 1 ];
for ( let i = 0; i < size; ++ i ) {
let theta = i % width;
const phi = Math.floor( i / width );
if ( endTheta - startTheta !== 0 && ( theta < startTheta || theta >= endTheta ) ) { // Handle symmetry for hor angles
theta %= endTheta * 2;
if ( theta > endTheta )
theta = endTheta * 2 - theta;
}
data[ phi + theta * height ] = interpolateCandelaValues( phi, theta );
}
let result = null;
if ( type === UnsignedByteType ) result = Uint8Array.from( data.map( v => Math.min( v * 0xFF, 0xFF ) ) );
else if ( type === HalfFloatType ) result = Uint16Array.from( data.map( v => DataUtils.toHalfFloat( v ) ) );
else if ( type === FloatType ) result = Float32Array.from( data );
else console.error( 'IESLoader: Unsupported type:', type );
return result;
}
load( url, onLoad, onProgress, onError ) {
const loader = new FileLoader( this.manager );
loader.setResponseType( 'text' );
loader.setCrossOrigin( this.crossOrigin );
loader.setWithCredentials( this.withCredentials );
loader.setPath( this.path );
loader.setRequestHeader( this.requestHeader );
loader.load( url, text => {
onLoad( this.parse( text ) );
}, onProgress, onError );
}
parse( text ) {
const type = this.type;
const iesLamp = new IESLamp( text );
const data = this._getIESValues( iesLamp, type );
const texture = new DataTexture( data, 180, 1, RedFormat, type );
texture.minFilter = LinearFilter;
texture.magFilter = LinearFilter;
texture.needsUpdate = true;
return texture;
}
}
function IESLamp( text ) {
const _self = this;
const textArray = text.split( '\n' );
let lineNumber = 0;
let line;
_self.verAngles = [ ];
_self.horAngles = [ ];
_self.candelaValues = [ ];
_self.tiltData = { };
_self.tiltData.angles = [ ];
_self.tiltData.mulFactors = [ ];
function textToArray( text ) {
text = text.replace( /^\s+|\s+$/g, '' ); // remove leading or trailing spaces
text = text.replace( /,/g, ' ' ); // replace commas with spaces
text = text.replace( /\s\s+/g, ' ' ); // replace white space/tabs etc by single whitespace
const array = text.split( ' ' );
return array;
}
function readArray( count, array ) {
while ( true ) {
const line = textArray[ lineNumber ++ ];
const lineData = textToArray( line );
for ( let i = 0; i < lineData.length; ++ i ) {
array.push( Number( lineData[ i ] ) );
}
if ( array.length === count )
break;
}
}
function readTilt() {
let line = textArray[ lineNumber ++ ];
let lineData = textToArray( line );
_self.tiltData.lampToLumGeometry = Number( lineData[ 0 ] );
line = textArray[ lineNumber ++ ];
lineData = textToArray( line );
_self.tiltData.numAngles = Number( lineData[ 0 ] );
readArray( _self.tiltData.numAngles, _self.tiltData.angles );
readArray( _self.tiltData.numAngles, _self.tiltData.mulFactors );
}
function readLampValues() {
const values = [ ];
readArray( 10, values );
_self.count = Number( values[ 0 ] );
_self.lumens = Number( values[ 1 ] );
_self.multiplier = Number( values[ 2 ] );
_self.numVerAngles = Number( values[ 3 ] );
_self.numHorAngles = Number( values[ 4 ] );
_self.gonioType = Number( values[ 5 ] );
_self.units = Number( values[ 6 ] );
_self.width = Number( values[ 7 ] );
_self.length = Number( values[ 8 ] );
_self.height = Number( values[ 9 ] );
}
function readLampFactors() {
const values = [ ];
readArray( 3, values );
_self.ballFactor = Number( values[ 0 ] );
_self.blpFactor = Number( values[ 1 ] );
_self.inputWatts = Number( values[ 2 ] );
}
while ( true ) {
line = textArray[ lineNumber ++ ];
if ( line.includes( 'TILT' ) ) {
break;
}
}
if ( ! line.includes( 'NONE' ) ) {
if ( line.includes( 'INCLUDE' ) ) {
readTilt();
} else {
// TODO:: Read tilt data from a file
}
}
readLampValues();
readLampFactors();
// Initialize candela value array
for ( let i = 0; i < _self.numHorAngles; ++ i ) {
_self.candelaValues.push( [ ] );
}
// Parse Angles
readArray( _self.numVerAngles, _self.verAngles );
readArray( _self.numHorAngles, _self.horAngles );
// Parse Candela values
for ( let i = 0; i < _self.numHorAngles; ++ i ) {
readArray( _self.numVerAngles, _self.candelaValues[ i ] );
}
// Calculate actual candela values, and normalize.
for ( let i = 0; i < _self.numHorAngles; ++ i ) {
for ( let j = 0; j < _self.numVerAngles; ++ j ) {
_self.candelaValues[ i ][ j ] *= _self.candelaValues[ i ][ j ] * _self.multiplier
* _self.ballFactor * _self.blpFactor;
}
}
let maxVal = - 1;
for ( let i = 0; i < _self.numHorAngles; ++ i ) {
for ( let j = 0; j < _self.numVerAngles; ++ j ) {
const value = _self.candelaValues[ i ][ j ];
maxVal = maxVal < value ? value : maxVal;
}
}
const bNormalize = true;
if ( bNormalize && maxVal > 0 ) {
for ( let i = 0; i < _self.numHorAngles; ++ i ) {
for ( let j = 0; j < _self.numVerAngles; ++ j ) {
_self.candelaValues[ i ][ j ] /= maxVal;
}
}
}
}
export { IESLoader };
