ENG-8627 | Fix .3ds files not rendering in MFR viewer

Author: sh-andriy

mfr/extensions/jsc3d/static/js/jsc3d.3ds.js

@@ -199,9 +199,12 @@ JSC3D.Autodesk3DSLoader.prototype.readAmount = function(reader,end) {
 	len = reader.readUInt32();
 
 	switch (cid) {
-		case 0x0030: // Floats
+		case 0x0030:
 			amount = reader.readUInt16();
 			break;
+		case 0x0031:
+			amount = reader.readFloat32() * 100.0;
+			break;
 		default:
 			break;
 	}
@@ -489,8 +492,8 @@ JSC3D.Autodesk3DSLoader.prototype.parseSmoothingGroups = function (reader) {
 JSC3D.Autodesk3DSLoader.prototype.finalizeCurrentMaterial = function () {
 	var mat = new JSC3D.Material;
 
-	if (this._cur_mat.colorMap) {
-		mat.textureFileName = this._cur_mat.colorMap.texture;
+	if (this._cur_mat.colorMap && this._cur_mat.colorMap.url) {
+		mat.textureFileName = this._cur_mat.colorMap.url;
 	}
 	else {
 		mat.diffuseColor = this._cur_mat.diffuseColor;
@@ -572,25 +575,59 @@ JSC3D.Autodesk3DSLoader.prototype.parse3DS = function(scene, data) {
 //			mesh.texCoordIndexBuffer = mesh.indexBuffer;
 			mesh.material = new JSC3D.Material;
 
-			var materialFaces = this._cur_obj.materialFaces;
-			var currentMaterial = null;
-			for(var materialName in materialFaces){
-				 currentMaterial = this._materials[materialName];
-				if (currentMaterial.colorMap) {
+			// Defaults: opaque & double-sided (helps open meshes)
+			mesh.material.transparency = 0;
+			mesh.isDoubleSided = true;
+			mesh.material.bothSides = true;
+
+			var materialFaces = this._cur_obj.materialFaces || {};
+			var sawMaterial = false;
+			for (var materialName in materialFaces) {
+				if (!Object.prototype.hasOwnProperty.call(materialFaces, materialName))
+					continue;
+				sawMaterial = true;
+
+				var currentMaterial = this._materials[materialName];
+				if (!currentMaterial) {
+					if (JSC3D.console) JSC3D.console.logWarning('3DS: missing material "' + materialName + '", using defaults.');
+					continue;
+				}
+
+				if (currentMaterial.colorMap && currentMaterial.colorMap.url) {
 					if(JSC3D.console)
-						JSC3D.console.logInfo('set texture: '+currentMaterial.colorMap.url);
+						JSC3D.console.logInfo('set texture: ' + currentMaterial.colorMap.url);
 					this.setupTexture([mesh], currentMaterial.colorMap.url);
 				}
-				else {
+				else if (currentMaterial.diffuseColor != null) {
 					mesh.material.diffuseColor = currentMaterial.diffuseColor;
 				}
-//				mesh.material.ambientColor = currentMaterial.ambientColor;
-//				mesh.material.simulateSpecular = (currentMaterial.specularColor>0);
-				mesh.isDoubleSided = true;//currentMaterial.twoSided;
-				mesh.material.transparency = currentMaterial.transparency>0?(currentMaterial.transparency)/100:0;
+
+				// Transparency: normalize (0..1), snap tiny values to 0 to avoid z-sort artifacts
+				var t = currentMaterial.transparency;
+				if (typeof t === 'number') {
+					var alpha = (t > 1) ? (t / 100.0) : t;
+					alpha = Math.max(0, Math.min(1, alpha));
+					if (alpha < 0.01) alpha = 0;
+					mesh.material.transparency = alpha;
+				} else {
+					mesh.material.transparency = 0;
+				}
+
+				var two = (currentMaterial.twoSided !== undefined) ? !!currentMaterial.twoSided : true;
+				mesh.isDoubleSided = two;
+				mesh.material.bothSides = two;
 			}
 
+			if (!sawMaterial) {
+				mesh.isDoubleSided = true;
+				mesh.material.bothSides = true;
+				mesh.material.transparency = 0;
+			}
 
+			if (!mesh.texCoordBuffer || !mesh.texCoordIndexBuffer) {
+				mesh.texCoordBuffer = null;
+				mesh.texCoordIndexBuffer = null;
+			}
 
 			//mesh.faceNormalBuffer = [];
 //			mesh.init();
@@ -672,7 +709,7 @@ JSC3D.Autodesk3DSLoader.prototype.parse3DS = function(scene, data) {
 				this._cur_obj = {};
 				this._cur_obj.name = this.readNulTermString(reader);
 				this._cur_obj.materials = [];
-				this._cur_obj.materialFaces = [];
+				this._cur_obj.materialFaces = {};
 				break;
 
 			case 0x4100: // OBJ_TRIMESH