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three

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JavaScript 3D library

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console.warn( "THREE.LightProbeGenerator: As part of the transition to ES6 Modules, the files in 'examples/js' were deprecated in May 2020 (r117) and will be deleted in December 2020 (r124). You can find more information about developing using ES6 Modules in https://threejs.org/docs/#manual/en/introduction/Installation." ); THREE.LightProbeGenerator = { // https://www.ppsloan.org/publications/StupidSH36.pdf fromCubeTexture: function ( cubeTexture ) { var norm, lengthSq, weight, totalWeight = 0; var coord = new THREE.Vector3(); var dir = new THREE.Vector3(); var color = new THREE.Color(); var shBasis = [ 0, 0, 0, 0, 0, 0, 0, 0, 0 ]; var sh = new THREE.SphericalHarmonics3(); var shCoefficients = sh.coefficients; for ( var faceIndex = 0; faceIndex < 6; faceIndex ++ ) { var image = cubeTexture.image[ faceIndex ]; var width = image.width; var height = image.height; var canvas = document.createElement( 'canvas' ); canvas.width = width; canvas.height = height; var context = canvas.getContext( '2d' ); context.drawImage( image, 0, 0, width, height ); var imageData = context.getImageData( 0, 0, width, height ); var data = imageData.data; var imageWidth = imageData.width; // assumed to be square var pixelSize = 2 / imageWidth; for ( var i = 0, il = data.length; i < il; i += 4 ) { // RGBA assumed // pixel color color.setRGB( data[ i ] / 255, data[ i + 1 ] / 255, data[ i + 2 ] / 255 ); // convert to linear color space convertColorToLinear( color, cubeTexture.encoding ); // pixel coordinate on unit cube var pixelIndex = i / 4; var col = - 1 + ( pixelIndex % imageWidth + 0.5 ) * pixelSize; var row = 1 - ( Math.floor( pixelIndex / imageWidth ) + 0.5 ) * pixelSize; switch ( faceIndex ) { case 0: coord.set( - 1, row, - col ); break; case 1: coord.set( 1, row, col ); break; case 2: coord.set( - col, 1, - row ); break; case 3: coord.set( - col, - 1, row ); break; case 4: coord.set( - col, row, 1 ); break; case 5: coord.set( col, row, - 1 ); break; } // weight assigned to this pixel lengthSq = coord.lengthSq(); weight = 4 / ( Math.sqrt( lengthSq ) * lengthSq ); totalWeight += weight; // direction vector to this pixel dir.copy( coord ).normalize(); // evaluate SH basis functions in direction dir THREE.SphericalHarmonics3.getBasisAt( dir, shBasis ); // accummuulate for ( var j = 0; j < 9; j ++ ) { shCoefficients[ j ].x += shBasis[ j ] * color.r * weight; shCoefficients[ j ].y += shBasis[ j ] * color.g * weight; shCoefficients[ j ].z += shBasis[ j ] * color.b * weight; } } } // normalize norm = ( 4 * Math.PI ) / totalWeight; for ( var j = 0; j < 9; j ++ ) { shCoefficients[ j ].x *= norm; shCoefficients[ j ].y *= norm; shCoefficients[ j ].z *= norm; } return new THREE.LightProbe( sh ); }, fromCubeRenderTarget: function ( renderer, cubeRenderTarget ) { // The renderTarget must be set to RGBA in order to make readRenderTargetPixels works var norm, lengthSq, weight, totalWeight = 0; var coord = new THREE.Vector3(); var dir = new THREE.Vector3(); var color = new THREE.Color(); var shBasis = [ 0, 0, 0, 0, 0, 0, 0, 0, 0 ]; var sh = new THREE.SphericalHarmonics3(); var shCoefficients = sh.coefficients; for ( var faceIndex = 0; faceIndex < 6; faceIndex ++ ) { var imageWidth = cubeRenderTarget.width; // assumed to be square var data = new Uint8Array( imageWidth * imageWidth * 4 ); renderer.readRenderTargetPixels( cubeRenderTarget, 0, 0, imageWidth, imageWidth, data, faceIndex ); var pixelSize = 2 / imageWidth; for ( var i = 0, il = data.length; i < il; i += 4 ) { // RGBA assumed // pixel color color.setRGB( data[ i ] / 255, data[ i + 1 ] / 255, data[ i + 2 ] / 255 ); // convert to linear color space convertColorToLinear( color, cubeRenderTarget.texture.encoding ); // pixel coordinate on unit cube var pixelIndex = i / 4; var col = - 1 + ( pixelIndex % imageWidth + 0.5 ) * pixelSize; var row = 1 - ( Math.floor( pixelIndex / imageWidth ) + 0.5 ) * pixelSize; switch ( faceIndex ) { case 0: coord.set( 1, row, - col ); break; case 1: coord.set( - 1, row, col ); break; case 2: coord.set( col, 1, - row ); break; case 3: coord.set( col, - 1, row ); break; case 4: coord.set( col, row, 1 ); break; case 5: coord.set( - col, row, - 1 ); break; } // weight assigned to this pixel lengthSq = coord.lengthSq(); weight = 4 / ( Math.sqrt( lengthSq ) * lengthSq ); totalWeight += weight; // direction vector to this pixel dir.copy( coord ).normalize(); // evaluate SH basis functions in direction dir THREE.SphericalHarmonics3.getBasisAt( dir, shBasis ); // accummuulate for ( var j = 0; j < 9; j ++ ) { shCoefficients[ j ].x += shBasis[ j ] * color.r * weight; shCoefficients[ j ].y += shBasis[ j ] * color.g * weight; shCoefficients[ j ].z += shBasis[ j ] * color.b * weight; } } } // normalize norm = ( 4 * Math.PI ) / totalWeight; for ( var j = 0; j < 9; j ++ ) { shCoefficients[ j ].x *= norm; shCoefficients[ j ].y *= norm; shCoefficients[ j ].z *= norm; } return new THREE.LightProbe( sh ); } }; var convertColorToLinear = function ( color, encoding ) { switch ( encoding ) { case THREE.sRGBEncoding: color.convertSRGBToLinear(); break; case THREE.LinearEncoding: break; default: console.warn( 'WARNING: LightProbeGenerator convertColorToLinear() encountered an unsupported encoding.' ); break; } return color; };