Initial commit of VIZ 3D project

src/utils/uvQuality.ts

@@ -0,0 +1,71 @@
+export interface UVQualityReport {
+  missingUVs: boolean;
+  extremeStretching: boolean;
+  overlappingUVs: boolean;
+  highComplexity: boolean;
+  recommendTriplanar: boolean;
+  details: {
+    vertexCount: number;
+    uvRange: [number, number];
+  };
+}
+
+export function analyzeUVQuality(
+  positions: Float32Array,
+  uvs?: Float32Array,
+  indices?: Uint32Array | Uint16Array
+): UVQualityReport {
+  const vertexCount = positions.length / 3;
+  const highComplexity = vertexCount > 50000; // Arbitrary threshold for complex geometry
+
+  if (!uvs || uvs.length === 0) {
+    return {
+      missingUVs: true,
+      extremeStretching: false,
+      overlappingUVs: false,
+      highComplexity,
+      recommendTriplanar: true,
+      details: {
+        vertexCount,
+        uvRange: [0, 0]
+      }
+    };
+  }
+
+  let minU = Infinity, maxU = -Infinity;
+  let minV = Infinity, maxV = -Infinity;
+
+  for (let i = 0; i < uvs.length; i += 2) {
+    const u = uvs[i];
+    const v = uvs[i + 1];
+    
+    if (u < minU) minU = u;
+    if (u > maxU) maxU = u;
+    if (v < minV) minV = v;
+    if (v > maxV) maxV = v;
+  }
+
+  const uRange = maxU - minU;
+  const vRange = maxV - minV;
+  
+  // Basic heuristic: if UVs are heavily clamped or barely cover any area
+  const extremeStretching = (uRange < 0.01 && uRange > 0) || (vRange < 0.01 && vRange > 0);
+  
+  // Overlapping detection is computationally expensive, skipping deep check for now
+  // A robust check would require comparing triangle areas in UV space vs World space
+  const overlappingUVs = false; 
+
+  const recommendTriplanar = extremeStretching || highComplexity;
+
+  return {
+    missingUVs: false,
+    extremeStretching,
+    overlappingUVs,
+    highComplexity,
+    recommendTriplanar,
+    details: {
+      vertexCount,
+      uvRange: [uRange, vRange]
+    }
+  };
+}