@google/model-viewer/lib/three-components/shader-chunk/normalmap_pars_fragment.glsl.d.ts

Easily display interactive 3D models on the web and in AR!

/**
 * @license MIT
 * @see https://github.com/mrdoob/three.js/blob/dev/LICENSE
 */
export declare const normalmapChunk = "\n#ifdef USE_NORMALMAP\n\n\tuniform sampler2D normalMap;\n\tuniform vec2 normalScale;\n\n#endif\n\n#ifdef OBJECTSPACE_NORMALMAP\n\n\tuniform mat3 normalMatrix;\n\n#endif\n\n#if ! defined ( USE_TANGENT ) && ( defined ( TANGENTSPACE_NORMALMAP ) || defined ( USE_CLEARCOAT_NORMALMAP ) )\n\n\t// Per-Pixel Tangent Space Normal Mapping\n\t// http://hacksoflife.blogspot.ch/2009/11/per-pixel-tangent-space-normal-mapping.html\n\n\tvec3 perturbNormal2Arb( vec3 eye_pos, vec3 surf_norm, vec2 normalScale, in sampler2D normalMap ) {\n\n\t\t// Workaround for Adreno 3XX dFd*( vec3 ) bug. See #9988\n\n\t\tvec3 q0 = vec3( dFdx( eye_pos.x ), dFdx( eye_pos.y ), dFdx( eye_pos.z ) );\n\t\tvec3 q1 = vec3( dFdy( eye_pos.x ), dFdy( eye_pos.y ), dFdy( eye_pos.z ) );\n\t\tvec2 st0 = dFdx( vUv.st );\n\t\tvec2 st1 = dFdy( vUv.st );\n\n\t\tfloat scale = sign( st1.t * st0.s - st0.t * st1.s ); // we do not care about the magnitude\n\n\t\tvec3 S = normalize( ( q0 * st1.t - q1 * st0.t ) * scale );\n\t\tvec3 T = normalize( ( - q0 * st1.s + q1 * st0.s ) * scale );\n\t\tvec3 N = normalize( surf_norm );\n\n\t\t// (elalish) Biased the normal mip to anti-alias the normal's screen-space derivatives\n\t\tvec3 mapN = texture2D( normalMap, vUv, 2.0 ).xyz * 2.0 - 1.0;\n\n\t\tmapN.xy *= normalScale;\n\n\t\t#ifdef DOUBLE_SIDED\n\n\t\t\t// Workaround for Adreno GPUs gl_FrontFacing bug. See #15850 and #10331\n\t\t\t// http://hacksoflife.blogspot.com/2009/11/per-pixel-tangent-space-normal-mapping.html?showComment=1522254677437#c5087545147696715943\n\t\t\tvec3 NfromST = cross( S, T );\n\t\t\tif( dot( NfromST, N ) > 0.0 ) {\n\n\t\t\t\tS *= -1.0;\n\t\t\t\tT *= -1.0;\n\n\t\t\t}\n\n\t\t#else\n\n\t\t\tmapN.xy *= ( float( gl_FrontFacing ) * 2.0 - 1.0 );\n\n\t\t#endif\n\n\t\tmat3 tsn = mat3( S, T, N );\n\t\treturn normalize( tsn * mapN );\n\n\t}\n\n#endif\n";