first app vibe

app/node_modules/three/src/nodes/accessors/TangentUtils.js

@@ -0,0 +1,46 @@
+import { uv as getUV } from './UV.js';
+import { positionView } from './Position.js';
+import { normalView } from './Normal.js';
+
+// Normal Mapping Without Precomputed Tangents
+// http://www.thetenthplanet.de/archives/1180
+
+const uv = getUV();
+
+const q0 = positionView.dFdx();
+const q1 = positionView.dFdy();
+const st0 = uv.dFdx();
+const st1 = uv.dFdy();
+
+const N = normalView;
+
+const q1perp = q1.cross( N );
+const q0perp = N.cross( q0 );
+
+const T = q1perp.mul( st0.x ).add( q0perp.mul( st1.x ) );
+const B = q1perp.mul( st0.y ).add( q0perp.mul( st1.y ) );
+
+const det = T.dot( T ).max( B.dot( B ) );
+const scale = det.equal( 0.0 ).select( 0.0, det.inverseSqrt() );
+
+/**
+ * Tangent vector in view space, computed dynamically from geometry and UV derivatives.
+ * Useful for normal mapping without precomputed tangents.
+ *
+ * Reference: http://www.thetenthplanet.de/archives/1180
+ *
+ * @tsl
+ * @type {Node<vec3>}
+ */
+export const tangentViewFrame = /*@__PURE__*/ T.mul( scale ).toVar( 'tangentViewFrame' );
+
+/**
+ * Bitangent vector in view space, computed dynamically from geometry and UV derivatives.
+ * Complements the tangentViewFrame for constructing the tangent space basis.
+ *
+ * Reference: http://www.thetenthplanet.de/archives/1180
+ *
+ * @tsl
+ * @type {Node<vec3>}
+ */
+export const bitangentViewFrame = /*@__PURE__*/ B.mul( scale ).toVar( 'bitangentViewFrame' );