Attempt to load missing resources by looking in the same directory as the obj

lib/loadMtl.js

@@ -222,6 +222,11 @@ function loadMaterialTexture(material, name, texturePath, textureOptions, mtlDir
             texturePromise = Promise.resolve();
         } else {
             texturePromise = loadTexture(texturePath, textureOptions)
+                .catch(function() {
+                    // Try looking for the texture in the same directory as the obj
+                    var shallowPath = path.resolve(path.join(mtlDirectory, path.basename(texturePath)));
+                    return loadTexture(shallowPath, textureOptions);
+                })
                 .catch(function() {
                     options.logger('Could not read texture file at ' + texturePath + '. This texture will be ignored.');
                 });

lib/loadObj.js

@@ -520,7 +520,13 @@ function loadMtls(mtlPaths, objPath, options) {
             options.logger('Could not read mtl file at ' + mtlPath + ' because it is outside of the obj directory and the secure flag is true. Using default material instead.');
             return;
         }
+
         return loadMtl(mtlPath, options)
+            .catch(function() {
+                // Try looking for the .mtl in the same directory as the obj
+                var shallowPath = path.resolve(path.join(objDirectory, path.basename(mtlPath)));
+                return loadMtl(shallowPath, options);
+            })
             .then(function(materialsInMtl) {
                 materials = materials.concat(materialsInMtl);
             })

specs/data/box-resources-in-root/box-resources-in-root.mtl

@@ -0,0 +1,13 @@
+# Blender MTL File: 'box.blend'
+# Material Count: 1
+
+newmtl Material
+Ns 96.078431
+Ka 0.000000 0.000000 0.000000
+Kd 0.640000 0.640000 0.640000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.000000
+d 1.000000
+illum 2
+map_Kd resources/textures/cesium.png

specs/data/box-resources-in-root/box-resources-in-root.obj

@@ -0,0 +1,46 @@
+# Blender v2.78 (sub 0) OBJ File: 'box.blend'
+# www.blender.org
+mtllib resources/box-resources-in-root.mtl
+o Cube
+v -1.000000 -1.000000 1.000000
+v -1.000000 1.000000 1.000000
+v -1.000000 -1.000000 -1.000000
+v -1.000000 1.000000 -1.000000
+v 1.000000 -1.000000 1.000000
+v 1.000000 1.000000 1.000000
+v 1.000000 -1.000000 -1.000000
+v 1.000000 1.000000 -1.000000
+vt 0.0000 0.0000
+vt 1.0000 0.0000
+vt 1.0000 1.0000
+vt 0.0000 1.0000
+vt 0.0000 0.0000
+vt 1.0000 0.0000
+vt 1.0000 1.0000
+vt 0.0000 1.0000
+vt 0.0000 0.0000
+vt 1.0000 0.0000
+vt 1.0000 1.0000
+vt 0.0000 1.0000
+vt 0.0000 0.0000
+vt 1.0000 0.0000
+vt 1.0000 1.0000
+vt 0.0000 1.0000
+vt 1.0000 0.0000
+vt 1.0000 1.0000
+vt 0.0000 0.0000
+vt 0.0000 1.0000
+vn -1.0000 0.0000 0.0000
+vn 0.0000 0.0000 -1.0000
+vn 1.0000 0.0000 0.0000
+vn 0.0000 0.0000 1.0000
+vn 0.0000 -1.0000 0.0000
+vn 0.0000 1.0000 0.0000
+usemtl Material
+s off
+f 1/1/1 2/2/1 4/3/1 3/4/1
+f 3/5/2 4/6/2 8/7/2 7/8/2
+f 7/9/3 8/10/3 6/11/3 5/12/3
+f 5/13/4 6/14/4 2/15/4 1/16/4
+f 3/5/5 7/17/5 5/18/5 1/16/5
+f 8/19/6 4/6/6 2/15/6 6/20/6

specs/lib/loadMtlSpec.js

@@ -14,6 +14,7 @@ var texturedMaterialPath = 'specs/data/box-complex-material/box-complex-material
 var texturedWithOptionsMaterialPath = 'specs/data/box-texture-options/box-texture-options.mtl';
 var multipleMaterialsPath = 'specs/data/box-multiple-materials/box-multiple-materials.mtl';
 var externalMaterialPath = 'specs/data/box-external-resources/box-external-resources.mtl';
+var resourcesInRootPath = 'specs/data/box-resources-in-root/box-resources-in-root.mtl';
 var transparentMaterialPath = 'specs/data/box-transparent/box-transparent.mtl';
 
 var diffuseTexturePath = 'specs/data/box-textured/cesium.png';
@@ -211,6 +212,16 @@ describe('loadMtl', function() {
             }), done).toResolve();
     });
 
+    it('loads textures from root directory when the texture paths do not exist', function(done) {
+        expect(loadMtl(resourcesInRootPath, options)
+            .then(function(materials) {
+                var material = materials[0];
+                var baseColorTexture = material.pbrMetallicRoughness.baseColorTexture;
+                expect(baseColorTexture.source).toBeDefined();
+                expect(baseColorTexture.name).toBe('cesium');
+            }), done).toResolve();
+    });
+
     it('alpha of 0.0 is treated as 1.0', function(done) {
         expect(loadMtl(transparentMaterialPath, options)
             .then(function(materials) {

specs/lib/loadObjSpec.js

@@ -23,6 +23,7 @@ var objUncleanedPath = 'specs/data/box-uncleaned/box-uncleaned.obj';
 var objMtllibPath = 'specs/data/box-mtllib/box-mtllib.obj';
 var objMissingMtllibPath = 'specs/data/box-missing-mtllib/box-missing-mtllib.obj';
 var objExternalResourcesPath = 'specs/data/box-external-resources/box-external-resources.obj';
+var objResourcesInRootPath = 'specs/data/box-resources-in-root/box-resources-in-root.obj';
 var objTexturedPath = 'specs/data/box-textured/box-textured.obj';
 var objMissingTexturePath = 'specs/data/box-missing-texture/box-missing-texture.obj';
 var objSubdirectoriesPath = 'specs/data/box-subdirectories/box-textured.obj';
@@ -327,6 +328,15 @@ describe('loadObj', function() {
             }), done).toResolve();
     });
 
+    it('loads .mtl from root directory when the .mtl path does not exist', function(done) {
+        expect(loadObj(objResourcesInRootPath, options)
+            .then(function(data) {
+                var baseColorTexture = data.materials[0].pbrMetallicRoughness.baseColorTexture;
+                expect(baseColorTexture.name).toBe('cesium');
+                expect(baseColorTexture.source).toBeDefined();
+            }), done).toResolve();
+    });
+
     it('loads obj with texture', function(done) {
         expect(loadObj(objTexturedPath, options)
             .then(function(data) {