<!-- NEW1 — TEST 1 · THE LIVING DISTRICT · part 312 -->
 = normalize( dFdx( surf_pos.xyz ) );\n\t\tvec3 vSigmaY = normalize( dFdy( surf_pos.xyz ) );\n\t\tvec3 vN = surf_norm;\n\t\tvec3 R1 = cross( vSigmaY, vN );\n\t\tvec3 R2 = cross( vN, vSigmaX );\n\t\tfloat fDet = dot( vSigmaX, R1 ) * faceDirection;\n\t\tvec3 vGrad = sign( fDet ) * ( dHdxy.x * R1 + dHdxy.y * R2 );\n\t\treturn normalize( abs( fDet ) * surf_norm - vGrad );\n\t}\n#endif";

var clipping_planes_fragment = "#if NUM_CLIPPING_PLANES > 0\n\tvec4 plane;\n\t#ifdef ALPHA_TO_COVERAGE\n\t\tfloat distanceToPlane, distanceGradient;\n\t\tfloat clipOpacity = 1.0;\n\t\t#pragma unroll_loop_start\n\t\tfor ( int i = 0; i < UNION_CLIPPING_PLANES; i ++ ) {\n\t\t\tplane = clippingPlanes[ i ];\n\t\t\tdistanceToPlane = - dot( vClipPosition, plane.xyz ) + plane.w;\n\t\t\tdistanceGradient = fwidth( distanceToPlane ) / 2.0;\n\t\t\tclipOpacity *= smoothstep( - distanceGradient, distanceGradient, distanceToPlane );\n\t\t\tif ( clipOpacity == 0.0 ) discard;\n\t\t}\n\t\t#pragma unroll_loop_end\n\t\t#if UNION_CLIPPING_PLANES < NUM_CLIPPING_PLANES\n\t\t\tfloat unionClipOpacity = 1.0;\n\t\t\t#pragma unroll_loop_start\n\t\t\tfor ( int i = UNION_CLIPPING_PLANES; i < NUM_CLIPPING_PLANES; i ++ ) {\n\t\t\t\tplane = clippingPlanes[ i ];\n\t\t\t\tdistanceToPlane = - dot( vClipPosition, plane.xyz ) + plane.w;\n\t\t\t\tdistanceGradient = fwidth( distanceToPlane ) / 2.0;\n\t\t\t\tunionClipOpacity *= 1.0 - smoothstep( - distanceGradient, distanceGradient, distanceToPlane );\n\t\t\t}\n\t\t\t#pragma unroll_loop_end\n\t\t\tclipOpacity *= 1.0 - unionClipOpacity;\n\t\t#endif\n\t\tdiffuseColor.a *= clipOpacity;\n\t\tif ( diffuseColor.a == 0.0 ) discard;\n\t#else\n\t\t#pragma unroll_loop_start\n\t\tfor ( int i = 0; i < UNION_CLIPPING_PLANES; i ++ ) {\n\t\t\tplane = clippingPlanes[ i ];\n\t\t\tif ( dot( vClipPosition, plane.xyz ) > plane.w ) discard;\n\t\t}\n\t\t#pragma unroll_loop_end\n\t\t#if UNION_CLIPPING_PLANES < NUM_CLIPPING_PLANES\n\t\t\tbool clipped = true;\n\t\t\t#pragma unroll_loop_start\n\t\t\tfor ( int i = UNION_CLIPPING_PLANES; i < NUM_CLIPPING_PLANES; i ++ ) {\n\t\t\t\tplane = clippingPlanes[ i ];\n\t\t\t\tclipped = ( dot( vClipPosition, plane.xyz ) > plane.w ) && clipped;\n\t\t\t}\n\t\t\t#pragma unroll_loop_end\n\t\t\tif ( clipped ) discard;\n\t\t#endif\n\t#endif\n#endif";

var clipping_planes_pars_fragment = "#if NUM_CLIPPING_PLANES > 0\n\tvarying vec3 vClipPosition;\n\tuniform vec4 clippingPlanes[ NUM_CLIPPING_PLANES ];\n#endif";

var clipping_planes_pars_vertex = "#if NUM_CLIPPING_PLANES > 0\n\tvarying vec3 vClipPosition;\n#endif";

var clipping_planes_vertex = "#if NUM_CLIPPING_PLANES > 0\n\tvClipPosition = - mvPosition.xyz;\n#endif";

var color_fragment = "#if defined( USE_COLOR ) || defined( USE_COLOR_ALPHA )\n\tdiffuseColor *= vColor;\n#endif";

var color_pars_fragment = "#if defined( USE_COLOR ) || defined( USE_COLOR_ALPHA )\n\tvarying vec4 vColor;\n#endif";

var color_pars_vertex = "#if defined( USE_COLOR ) || defined( USE_COLOR_ALPHA ) || defined( USE_INSTANCING_COLOR ) || defined( USE_BATCHING_COLOR )\n\tvarying vec4 vColor;\n#endif";

var color_vertex = "#if defined( USE_COLOR ) || defined( USE_COLOR_ALPHA ) || defined( USE_INSTANCING_COLOR ) || defined( USE_BATCHING_COLOR )\n\tvColor = vec4( 1.0 );\n#endif\n#ifdef USE_COLOR_ALPHA\n\tvColor *= color;\n#elif defined( USE_COLOR )\n\tvColor.rgb *= color;\n#endif\n#ifdef USE_INSTANCING_COLOR\n\tvColor.rgb *= instanceColor.rgb;\n#endif\n#ifdef USE_BATCHING_COLOR\n\tvColor *= getBatchingColor( getIndirectIndex( gl_DrawID ) );\n#endif";

var common = "#define PI 3.141592653589793\n#define PI2 6.283185307179586\n#define PI_HALF 1.5707963267948966\n#define RECIPROCAL_PI 0.3183098861837907\n#define RECIPROCAL_PI2 0.15915494309189535\n#define EPSILON 1e-6\n#ifndef saturate\n#define saturate( a ) clamp( a, 0.0, 1.0 )\n#endif\n#define whiteComplement( a ) ( 1.0 - saturate( a ) )\nfloat pow2( const in float x ) { return x*x; }\nvec3 pow2( const in vec3 x ) { return x*x; }\nfloat pow3( const in float x ) { return x*x*x; }\nfloat pow4( const in float x ) { float x2 = x*x; return x2*x2; }\nfloat max3( const in vec3 v ) { return max( max( v.x, v.y ), v.z ); }\nfloat average( const in vec3 v ) { return dot( v, vec3( 0.3333333 ) ); }\nhighp float rand( const in vec2 uv ) {\n\tconst highp float a = 12.9898, b = 78.233, c = 43758.5453;\n\thighp float dt = dot( uv.xy, vec2( a,b ) ), sn = mod( dt, PI );\n\treturn fract( sin( sn ) * c );\n}\n#ifdef HIGH_PRECISION\n\tfloat precisionSafeLength( vec3 v ) { return length( v ); }\n#else\n\tfloat precisionSafeLength( vec3 v ) {\n\t\tfloat maxComponent = max3( abs( v ) );\n\t\treturn length( v / maxComponent ) * maxComponent;\n\t}\n#endif\nstruct IncidentLight {\n\tvec3 color;\n\tvec3 direction;\n\tbool visible;\n};\nstruct ReflectedLight {\n\tvec3 directDiffuse;\n\tvec3 directSpecular;\n\tvec3 indirectDiffuse;\n\tvec3 indirectSpecular;\n};\n#ifdef USE_ALPHAHASH\n\tvarying vec3 vPosition;\n#endif