split.html 10 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340
  1. <html>
  2. <title>Split STL mesh</title>
  3. <body>
  4. <p>This is a simple piece of javascript (licensed under the MIT license) by
  5. <a href="http://www.thingiverse.com/arpruss/">Alexander Pruss</a> that splits an STL mesh file that contains multiple parts into
  6. those multiple parts.</p>
  7. <p>This may well fail if the mesh is defective and has points that are meant to be coincident
  8. but are merely close together.</p>
  9. <p>All the processing is done in your browser--your STL is not uploaded to any server.</p>
  10. <input type="file" id="file" name="file" />
  11. <ul id="console">
  12. </ul>
  13. <script>
  14. var TRIANGLE_SIZE = (3+3*3)*4+2;
  15. var ASCII_MODE = true;
  16. var allSplitMeshes = [];
  17. var baseFilaname = "";
  18. function getString(view, position, length) {
  19. var out = "";
  20. for (var i=0; i<length; i++) {
  21. var b = view.getUint8(position + i);
  22. out += String.fromCharCode(b);
  23. }
  24. return out;
  25. }
  26. // For hashing during splitting, ASCII mode is used, where vectors are stored
  27. // as strings. From a binary STL, the vectors are stored as hex strings, and
  28. // from an ASCII STL, they are stored as directly extracted ASCII.
  29. function getVector(view, position) {
  30. if (ASCII_MODE) {
  31. function fixZero(a) {
  32. return a == 0x80000000 ? 0 : a;
  33. }
  34. x = fixZero(view.getUint32(position, true));
  35. y = fixZero(view.getUint32(position+4, true));
  36. z = fixZero(view.getUint32(position+8, true));
  37. return x.toString(16)+":"+y.toString(16)+":"+z.toString(16);
  38. }
  39. x = view.getFloat32(position, true);
  40. y = view.getFloat32(position+4, true);
  41. z = view.getFloat32(position+8, true);
  42. return [x,y,z]; // x.toString()+","+y.toString()+","+z.toString(); //[x,y,z];
  43. }
  44. function parseVector(vector) {
  45. if (typeof vector === "string") {
  46. var data = vector.split(":");
  47. var buf = new ArrayBuffer(4);
  48. var view = new DataView(buf);
  49. function parse(s) {
  50. view.setUint32(0, parseInt(s,16));
  51. return view.getFloat32(0);
  52. }
  53. return [parse(data[0]),parse(data[1]),parse(data[2])];
  54. }
  55. else {
  56. return vector;
  57. }
  58. }
  59. function setVector(view, position, vector) {
  60. if (typeof vector === "string") {
  61. var data = vector.split(":");
  62. view.setUint32(position, parseInt(data[0],16), true);
  63. view.setUint32(position+4, parseInt(data[1],16), true);
  64. view.setUint32(position+8, parseInt(data[2],16), true);
  65. }
  66. else {
  67. view.setFloat32(position, vector[0], true);
  68. view.setFloat32(position+4, vector[1], true);
  69. view.setFloat32(position+8, vector[2], true);
  70. }
  71. }
  72. function getVectorFromText(line, position) {
  73. var data = line.substr(position).split(/[\s,]+/);
  74. if (data.length < 3)
  75. throw 'Invalid vector';
  76. if (ASCII_MODE) {
  77. var buf = new ArrayBuffer(4);
  78. var view = new DataView(buf);
  79. function toHex32(number) {
  80. view.setFloat32(0, parseFloat(number));
  81. return view.getUint32(0).toString(16);
  82. }
  83. return toHex32(data[0])+":"+toHex32(data[1])+":"+toHex32(data[2]);
  84. }
  85. return [parseFloat(data[0]), parseFloat(data[1]), parseFloat(data[2])];
  86. }
  87. function message(text) {
  88. document.getElementById('console').innerHTML += '<li>'+text+'</li>';
  89. }
  90. function getASCIISTL(text) {
  91. var triangles = [];
  92. var triangle = [];
  93. var normal = [0,0,0];
  94. var lines = text.split(/[\r\n]+/);
  95. message(lines.length+" lines of data");
  96. for (var i = 0 ; i < lines.length ; i++ ) {
  97. l = lines[i].trim().toLowerCase();
  98. if (l == 'endfacet') {
  99. if (triangle.length != 3)
  100. throw 'invalid triangle';
  101. triangles.push([triangle[0],triangle[1],triangle[2],normal]);
  102. triangle = [];
  103. normal = [0,0,0];
  104. }
  105. else if (l.startsWith('facet')) {
  106. if (l.length > 6) {
  107. if (l.substr(6).startsWith('normal'))
  108. normal = getVectorFromText(l, 13);
  109. }
  110. }
  111. else if (l.startsWith('vertex')) {
  112. if (l.length > 7)
  113. triangle.push(getVectorFromText(l, 7));
  114. }
  115. }
  116. message(String(triangles.length) + " triangles");
  117. return triangles;
  118. }
  119. function getBinarySTL(view) {
  120. var triangles = [];
  121. var numTriangles = view.getUint32(80, true);
  122. message(String(numTriangles) + " triangles");
  123. for (var i = 0 ; i < numTriangles ; i++) {
  124. position = 84 + TRIANGLE_SIZE*i;
  125. normal = getVector(view, position);
  126. v1 = getVector(view, position+12);
  127. v2 = getVector(view, position+12*2);
  128. v3 = getVector(view, position+12*3);
  129. triangles.push( [v1,v2,v3,normal] );
  130. }
  131. return triangles;
  132. }
  133. function splitMesh(triangles) {
  134. meshes = [];
  135. for (var i = 0; i<triangles.length; i++) {
  136. var t = triangles[i];
  137. var matches = [];
  138. for (var j = 0 ; j < meshes.length; j++) {
  139. for (var k = 0 ; k < 3 ; k++) {
  140. if (t[k] in meshes[j].points) {
  141. matches.push(j);
  142. break;
  143. }
  144. }
  145. }
  146. var m;
  147. if (matches.length == 0) {
  148. m = {points:{}, triangles:[]};
  149. meshes.push(m);
  150. }
  151. else {
  152. m = meshes[matches[0]];
  153. for (var j = matches.length - 1 ; j >= 1 ; j--) {
  154. mm = meshes[matches[j]];
  155. for (var key in mm.points) {
  156. if (mm.points.hasOwnProperty(key))
  157. m.points[key] = true;
  158. }
  159. for (var k = 0 ; k < mm.triangles.length; k++) {
  160. m.triangles.push(mm.triangles[k]);
  161. }
  162. meshes.splice(matches[j], 1);
  163. }
  164. }
  165. for (var k = 0 ; k < 3 ; k++) {
  166. m.points[t[k]] = true;
  167. }
  168. m.triangles.push(t);
  169. }
  170. for (var i = 0 ; i < meshes.length ; i++) {
  171. var bounds = [Number.POSITIVE_INFINITY, Number.POSITIVE_INFINITY, Number.POSITIVE_INFINITY,
  172. Number.NEGATIVE_INFINITY, Number.NEGATIVE_INFINITY, Number.NEGATIVE_INFINITY ];
  173. for (var key in meshes[i].points) {
  174. if (meshes[i].points.hasOwnProperty(key)) {
  175. var v = parseVector(key);
  176. for (var k=0; k<3; k++) {
  177. bounds[k] = Math.min(bounds[k], v[k]);
  178. bounds[3+k] = Math.max(bounds[3+k], v[k]);
  179. }
  180. }
  181. }
  182. meshes[i].bounds = bounds;
  183. delete meshes[i].points;
  184. }
  185. function compareByBounds(m,m) {
  186. for (var i=0; i<6; i++) {
  187. if (m.bounds[i] < m.bounds[i])
  188. return -1;
  189. else if (m.bounds[i] < m.bounds[i])
  190. return -1;
  191. }
  192. return 0;
  193. }
  194. meshes.sort(compareByBounds);
  195. return meshes;
  196. }
  197. function downloadBlob(name,blob) {
  198. var link = document.createElement('a');
  199. link.download = name;
  200. link.href = window.URL.createObjectURL(blob);
  201. link.onclick = function(e) {
  202. setTimeout(function() {
  203. window.URL.revokeObjectURL(link.href);
  204. }, 1600);
  205. };
  206. link.click();
  207. link.remove();
  208. }
  209. function makeMeshByteArray(triangles) {
  210. data = new ArrayBuffer(84 + triangles.length * TRIANGLE_SIZE);
  211. view = new DataView(data);
  212. view.setUint32(80, triangles.length, true);
  213. for (var i=0; i<triangles.length; i++) {
  214. var offset = 84 + i*TRIANGLE_SIZE;
  215. setVector(view, offset, triangles[i][3]); // normal
  216. setVector(view, offset+12, triangles[i][0]); // v1
  217. setVector(view, offset+12*2, triangles[i][1]); // v2
  218. setVector(view, offset+12*3, triangles[i][2]); // v3
  219. }
  220. return view.buffer;
  221. }
  222. function downloadMesh(i) {
  223. downloadBlob(baseFilename+i+".stl", new Blob([makeMeshByteArray(allSplitMeshes[i])], {type: "application/octet-stream"}));
  224. }
  225. function describeBounds(bounds) {
  226. return "("+bounds[0].toFixed(2)+", "+bounds[1].toFixed(2)+", "+bounds[2].toFixed(2)+") - ("+
  227. bounds[3].toFixed(2)+", "+bounds[4].toFixed(2)+", "+bounds[5].toFixed(2)+")";
  228. }
  229. function processSTL(data) {
  230. length = data.byteLength;
  231. view = new DataView(data);
  232. var header = getString(view, 0, 5);
  233. var binary = true;
  234. var text;
  235. if (header == "solid") {
  236. // probably ASCII
  237. text = getString(view, 0, length);
  238. if (text.includes("endfacet")) {
  239. binary = false;
  240. }
  241. }
  242. message(binary ? "binary STL" : "ASCII STL");
  243. triangles = binary ? getBinarySTL(view) : getASCIISTL(text);
  244. message("data successfully read");
  245. splitMeshes = splitMesh(triangles);
  246. if (splitMeshes.length == 1) {
  247. message("No splitting done: Only one mesh in file.");
  248. }
  249. else if (splitMeshes.length == 0) {
  250. message("No mesh found in file.");
  251. }
  252. else {
  253. message(String(splitMeshes.length)+" meshes extracted");
  254. allSplitMeshes = [];
  255. for (var i=0; i<splitMeshes.length; i++) {
  256. allSplitMeshes.push(splitMeshes[i].triangles);
  257. message("<a href='#' onclick='downloadMesh("+i+");'>Download mesh part "+i+"</a> "+describeBounds(splitMeshes[i].bounds));
  258. }
  259. }
  260. }
  261. function handleFileSelect(evt) {
  262. var e = document.getElementById('file');
  263. e.disabled = true;
  264. document.getElementById('console').innerHTML = '';
  265. var f = evt.target.files[0];
  266. message( String(f.size) + ' bytes');
  267. var n = f.name.split(/[/\\]+/);
  268. baseFilename = f.name.replace(/.*[/\\]/, "").replace(/\.[sS][tT][lL]$/, "");
  269. var reader = new FileReader();
  270. reader.onload = function(event) {
  271. try {
  272. processSTL(event.target.result);
  273. }
  274. catch(err) {
  275. message( "Error: "+err);
  276. }
  277. var e = document.getElementById('file');
  278. e.disabled = false;
  279. }
  280. reader.readAsArrayBuffer(f);
  281. }
  282. document.getElementById('file').addEventListener('change', handleFileSelect, false);
  283. </script>
  284. </body>
  285. </html>