File size: 4,408 Bytes
71174bc | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 | /**
* VRML file processing utilities for parsing, modifying,
* and reconstructing VRML content during mesh optimization.
*/
import { truncateValues } from "./Math";
import { mergeVertices, updateIndices } from "./MergeVerticesByDistance";
import { parseVRML, replaceVerticesAndIndicesInVRML } from "./ParseVRML";
import { simplifyMesh } from "./QEM";
// Helper function to count faces
/**
* Count the number of faces in a mesh.
*
* @param {number[]} indices The indices of the mesh.
* @returns {number} The number of faces in the mesh.
*/
function countFaces(indices: number[]): number {
return indices.filter((index) => index === -1 && index !== undefined)
.length;
}
/**
* Process a VRML file by merging vertices, simplifying the mesh, and replacing
* the vertices and indices in the VRML content.
*
* @param {string} content The content of the VRML file.
* @param {number} mergeCutoff The distance cutoff for merging vertices.
* @param {number} reductionFraction The fraction of vertices to reduce to.
* @returns {Promise<string>} The processed VRML content.
*/
export async function processVRML(
content: string,
mergeCutoff: number,
reductionFraction: number
): Promise<string> {
const { chunkDatas, firstChunkContent } = parseVRML(content);
const newVRMLContents: string[] = [];
for (const chunkDataIdx in chunkDatas) {
const chunkData = chunkDatas[chunkDataIdx];
const { vertices, indices, colors, normals, shapeChunkContent } =
chunkData;
console.log("Original mesh:");
console.log(` Vertices: ${vertices.length}`);
console.log(` Faces: ${countFaces(indices)}`);
// Merge vertices by distance and color
const { mergedVertices, mergedColors, mapping } = mergeVertices(
vertices,
colors,
mergeCutoff
);
const updatedIndices = updateIndices(indices, mapping);
console.log("After vertex merging:");
console.log(` Vertices: ${mergedVertices.length}`);
console.log(` Faces: ${countFaces(updatedIndices)}`);
// Calculate target vertex count based on reduction fraction
let targetVertexCount = null;
if (reductionFraction !== null) {
targetVertexCount = Math.round(
mergedVertices.length * reductionFraction
);
// console.log(`Target vertex count: ${targetVertexCount} (${reductionFraction * 100}% of merged vertices)`);
}
// Simplify the mesh using Vertex Clustering if targetVertexCount is provided
let simplifiedVertices = mergedVertices;
let simplifiedIndices = updatedIndices;
let simplifiedColors = mergedColors;
if (targetVertexCount) {
const simplifiedMesh = simplifyMesh(
mergedVertices,
updatedIndices,
mergedColors,
targetVertexCount
);
simplifiedVertices = simplifiedMesh.vertices.map(truncateValues);
simplifiedIndices = simplifiedMesh.indices;
simplifiedColors = simplifiedMesh.colors.map(truncateValues);
console.log("After Vertex Clustering simplification:");
console.log(` Vertices: ${simplifiedVertices.length}`);
console.log(` Faces: ${countFaces(simplifiedIndices)}`);
}
// Truncate normals if they exist
const mergedNormals =
normals.length > 0 ? normals.map(truncateValues) : normals;
// Replace vertices, colors, normals, and indices in VRML
const newVRMLContent = replaceVerticesAndIndicesInVRML(
shapeChunkContent,
simplifiedVertices,
simplifiedColors,
mergedNormals,
simplifiedIndices
);
// console.log(newVRMLContent.slice(0, 1000));
newVRMLContents.push(newVRMLContent);
// fs.writeFileSync(outputFile + "_" + vrmlChunkIdx.toString() + ".wrl", newVRMLContent);
// console.log(`Processed VRML file saved as ${outputFile}`);
// console.log(newVRMLContent);
console.log("");
}
const newVRMLContent =
firstChunkContent + "Shape {" + newVRMLContents.join("Shape {");
console.log(newVRMLContents.length);
console.log(newVRMLContent);
return newVRMLContent;
}
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