Adding position, normals, and uvs to primitive level rather than mesh level

lib/createGltf.js

@@ -131,10 +131,8 @@ function addBufferView(gltf, buffers, accessors, byteStride, target) {
 }
 
 function addBuffers(gltf, bufferState, name) {
-    // Positions and normals share the same byte stride so they can share the same bufferView
+    addBufferView(gltf, bufferState.positionBuffers, bufferState.positionAccessors, 12, WebGLConstants.ARRAY_BUFFER);
-    var positionsAndNormalsAccessors = bufferState.positionAccessors.concat(bufferState.normalAccessors);
+    addBufferView(gltf, bufferState.normalBuffers, bufferState.normalAccessors, 12, WebGLConstants.ARRAY_BUFFER);
-    var positionsAndNormalsBuffers = bufferState.positionBuffers.concat(bufferState.normalBuffers);
-    addBufferView(gltf, positionsAndNormalsBuffers, positionsAndNormalsAccessors, 12, WebGLConstants.ARRAY_BUFFER);
     addBufferView(gltf, bufferState.uvBuffers, bufferState.uvAccessors, 8, WebGLConstants.ARRAY_BUFFER);
     addBufferView(gltf, bufferState.indexBuffers, bufferState.indexAccessors, undefined, WebGLConstants.ELEMENT_ARRAY_BUFFER);
 
@@ -297,68 +295,73 @@ function requiresUint32Indices(nodes) {
         var meshes = nodes[i].meshes;
         var meshesLength = meshes.length;
         for (var j = 0; j < meshesLength; ++j) {
+            var primitives = meshes[j].primitives;
+            var primitivesLength = primitives.length;
+            for (var k = 0; k < primitivesLength; ++k) {
                 // Reserve the 65535 index for primitive restart
-            var vertexCount = meshes[j].positions.length / 3;
+                var vertexCount = primitives[k].positions.length / 3;
                 if (vertexCount > 65534) {
                     return true;
                 }
             }
         }
+    }
     return false;
 }
 
-function addMesh(gltf, materials, bufferState, uint32Indices, mesh, options) {
+function addPrimitive(gltf, materials, bufferState, uint32Indices, mesh, primitive, index, options) {
-    var hasPositions = mesh.positions.length > 0;
+    var hasPositions = primitive.positions.length > 0;
-    var hasNormals = mesh.normals.length > 0;
+    var hasNormals = primitive.normals.length > 0;
-    var hasUVs = mesh.uvs.length > 0;
+    var hasUVs = primitive.uvs.length > 0;
 
-    // Vertex attributes are shared by all primitives in the mesh
     var accessorIndex;
     var attributes = {};
     if (hasPositions) {
-        accessorIndex = addVertexAttribute(gltf, mesh.positions, 3, mesh.name + '_positions');
+        accessorIndex = addVertexAttribute(gltf, primitive.positions, 3, mesh.name + '_' + index + '_positions');
         attributes.POSITION = accessorIndex;
-        bufferState.positionBuffers.push(mesh.positions.toFloatBuffer());
+        bufferState.positionBuffers.push(primitive.positions.toFloatBuffer());
         bufferState.positionAccessors.push(accessorIndex);
     }
     if (hasNormals) {
-        accessorIndex = addVertexAttribute(gltf, mesh.normals, 3, mesh.name + '_normals');
+        accessorIndex = addVertexAttribute(gltf, primitive.normals, 3, mesh.name + '_' + index + '_normals');
         attributes.NORMAL = accessorIndex;
-        bufferState.normalBuffers.push(mesh.normals.toFloatBuffer());
+        bufferState.normalBuffers.push(primitive.normals.toFloatBuffer());
         bufferState.normalAccessors.push(accessorIndex);
     }
     if (hasUVs) {
-        accessorIndex = addVertexAttribute(gltf, mesh.uvs, 2, mesh.name + '_texcoords');
+        accessorIndex = addVertexAttribute(gltf, primitive.uvs, 2, mesh.name + '_' + index + '_texcoords');
         attributes.TEXCOORD_0 = accessorIndex;
-        bufferState.uvBuffers.push(mesh.uvs.toFloatBuffer());
+        bufferState.uvBuffers.push(primitive.uvs.toFloatBuffer());
         bufferState.uvAccessors.push(accessorIndex);
     }
 
-    // Unload resources
+    var indexAccessorIndex = addIndexArray(gltf, primitive.indices, uint32Indices, mesh.name + '_' + index + '_indices');
-    mesh.positions = undefined;
-    mesh.normals = undefined;
-    mesh.uvs = undefined;
-
-    var gltfPrimitives = [];
-    var primitives = mesh.primitives;
-    var primitivesLength = primitives.length;
-    for (var i = 0; i < primitivesLength; ++i) {
-        var primitive = primitives[i];
-        var indexAccessorIndex = addIndexArray(gltf, primitive.indices, uint32Indices, mesh.name + '_' + i + '_indices');
     var indexBuffer = uint32Indices ? primitive.indices.toUint32Buffer() : primitive.indices.toUint16Buffer();
     bufferState.indexBuffers.push(indexBuffer);
     bufferState.indexAccessors.push(indexAccessorIndex);
 
-        primitive.indices = undefined; // Unload resources
+    // Unload resources
+    primitive.positions = undefined;
+    primitive.normals = undefined;
+    primitive.uvs = undefined;
+    primitive.indices = undefined;
 
     var materialIndex = getMaterial(gltf, materials, primitive.material, options);
 
-        gltfPrimitives.push({
+    return {
         attributes : attributes,
         indices : indexAccessorIndex,
         material : materialIndex,
         mode : WebGLConstants.TRIANGLES
-        });
+    };
+}
+
+function addMesh(gltf, materials, bufferState, uint32Indices, mesh, options) {
+    var gltfPrimitives = [];
+    var primitives = mesh.primitives;
+    var primitivesLength = primitives.length;
+    for (var i = 0; i < primitivesLength; ++i) {
+        gltfPrimitives.push(addPrimitive(gltf, materials, bufferState, uint32Indices, mesh, primitives[i], i, options));
     }
 
     var gltfMesh = {

lib/loadObj.js

@@ -36,14 +36,14 @@ function Node() {
 function Mesh() {
     this.name = undefined;
     this.primitives = [];
-    this.positions = new ArrayStorage(ComponentDatatype.FLOAT);
-    this.normals = new ArrayStorage(ComponentDatatype.FLOAT);
-    this.uvs = new ArrayStorage(ComponentDatatype.FLOAT);
 }
 
 function Primitive() {
     this.material = undefined;
     this.indices = new ArrayStorage(ComponentDatatype.UNSIGNED_INT);
+    this.positions = new ArrayStorage(ComponentDatatype.FLOAT);
+    this.normals = new ArrayStorage(ComponentDatatype.FLOAT);
+    this.uvs = new ArrayStorage(ComponentDatatype.FLOAT);
 }
 
 // OBJ regex patterns are modified from ThreeJS (https://github.com/mrdoob/three.js/blob/master/examples/js/loaders/OBJLoader.js)
@@ -76,7 +76,7 @@ function loadObj(objPath, options) {
     // All nodes seen in the obj
     var nodes = [];
 
-    // Used to build the indices. The vertex cache is unique to each mesh.
+    // Used to build the indices. The vertex cache is unique to each primitive.
     var vertexCache = {};
     var vertexCacheLimit = 1000000;
     var vertexCacheCount = 0;
@@ -158,9 +158,9 @@ function loadObj(objPath, options) {
             var px = positions.get(pi + 0);
             var py = positions.get(pi + 1);
             var pz = positions.get(pi + 2);
-            mesh.positions.push(px);
+            primitive.positions.push(px);
-            mesh.positions.push(py);
+            primitive.positions.push(py);
-            mesh.positions.push(pz);
+            primitive.positions.push(pz);
         }
 
         // Normals
@@ -169,9 +169,9 @@ function loadObj(objPath, options) {
             var nx = normals.get(ni + 0);
             var ny = normals.get(ni + 1);
             var nz = normals.get(ni + 2);
-            mesh.normals.push(nx);
+            primitive.normals.push(nx);
-            mesh.normals.push(ny);
+            primitive.normals.push(ny);
-            mesh.normals.push(nz);
+            primitive.normals.push(nz);
         }
 
         // UVs
@@ -179,8 +179,8 @@ function loadObj(objPath, options) {
             var ui = getOffset(u, uvs, 2);
             var ux = uvs.get(ui + 0);
             var uy = uvs.get(ui + 1);
-            mesh.uvs.push(ux);
+            primitive.uvs.push(ux);
-            mesh.uvs.push(uy);
+            primitive.uvs.push(uy);
         }
     }
 
@@ -614,10 +614,10 @@ function removeEmptyMeshes(meshes) {
     return meshes.filter(function(mesh) {
         // Remove empty primitives
         mesh.primitives = mesh.primitives.filter(function(primitive) {
-            return primitive.indices.length > 0;
+            return primitive.indices.length > 0 && primitive.positions.length > 0;
         });
-        // Valid meshes must have at least one primitive and contain positions
+        // Valid meshes must have at least one primitive
-        return (mesh.primitives.length > 0) && (mesh.positions.length > 0);
+        return (mesh.primitives.length > 0);
     });
 }
 

specs/lib/createGltfSpec.js

@@ -133,42 +133,42 @@ describe('createGltf', function() {
     });
 
     it('runs without normals', function() {
-        boxObjData.nodes[0].meshes[0].normals.length = 0;
+        boxObjData.nodes[0].meshes[0].primitives[0].normals.length = 0;
 
         var gltf = createGltf(boxObjData, options);
-        var attributes = gltf.meshes[Object.keys(gltf.meshes)[0]].primitives[0].attributes;
+        var attributes = gltf.meshes[0].primitives[0].attributes;
         expect(attributes.POSITION).toBeDefined();
         expect(attributes.NORMAL).toBeUndefined();
         expect(attributes.TEXCOORD_0).toBeDefined();
     });
 
     it('runs without uvs', function() {
-        boxObjData.nodes[0].meshes[0].uvs.length = 0;
+        boxObjData.nodes[0].meshes[0].primitives[0].uvs.length = 0;
 
         var gltf = createGltf(boxObjData, options);
-        var attributes = gltf.meshes[Object.keys(gltf.meshes)[0]].primitives[0].attributes;
+        var attributes = gltf.meshes[0].primitives[0].attributes;
         expect(attributes.POSITION).toBeDefined();
         expect(attributes.NORMAL).toBeDefined();
         expect(attributes.TEXCOORD_0).toBeUndefined();
     });
 
     it('runs without uvs and normals', function() {
-        boxObjData.nodes[0].meshes[0].normals.length = 0;
+        boxObjData.nodes[0].meshes[0].primitives[0].normals.length = 0;
-        boxObjData.nodes[0].meshes[0].uvs.length = 0;
+        boxObjData.nodes[0].meshes[0].primitives[0].uvs.length = 0;
 
         var gltf = createGltf(boxObjData, options);
-        var attributes = gltf.meshes[Object.keys(gltf.meshes)[0]].primitives[0].attributes;
+        var attributes = gltf.meshes[0].primitives[0].attributes;
         expect(attributes.POSITION).toBeDefined();
         expect(attributes.NORMAL).toBeUndefined();
         expect(attributes.TEXCOORD_0).toBeUndefined();
     });
 
     function expandObjData(objData, duplicatesLength) {
-        var mesh = objData.nodes[0].meshes[0];
+        var primitive = objData.nodes[0].meshes[0].primitives[0];
-        var indices = mesh.primitives[0].indices;
+        var indices = primitive.indices;
-        var positions = mesh.positions;
+        var positions = primitive.positions;
-        var normals = mesh.normals;
+        var normals = primitive.normals;
-        var uvs = mesh.uvs;
+        var uvs = primitive.uvs;
 
         var indicesLength = indices.length;
         var vertexCount = positions.length / 3;
@@ -192,12 +192,12 @@ describe('createGltf', function() {
 
     it('detects need to use uint32 indices', function() {
         expandObjData(boxObjData, 2731); // Right above 65536 limit
-        var mesh = boxObjData.nodes[0].meshes[0];
+        var primitive = boxObjData.nodes[0].meshes[0].primitives[0];
-        var indicesLength = mesh.primitives[0].indices.length;
+        var indicesLength = primitive.indices.length;
-        var vertexCount = mesh.positions.length / 3;
+        var vertexCount = primitive.positions.length / 3;
 
         var gltf = createGltf(boxObjData, options);
-        var primitive = gltf.meshes[Object.keys(gltf.meshes)[0]].primitives[0];
+        primitive = gltf.meshes[0].primitives[0];
         var indicesAccessor = gltf.accessors[primitive.indices];
         expect(indicesAccessor.count).toBe(indicesLength);
         expect(indicesAccessor.max[0]).toBe(vertexCount - 1);

specs/lib/loadObjSpec.js

@@ -94,9 +94,9 @@ describe('loadObj', function() {
 
                 expect(node.name).toBe('Cube');
                 expect(mesh.name).toBe('Cube-Mesh');
-                expect(mesh.positions.length / 3).toBe(24);
+                expect(primitive.positions.length / 3).toBe(24);
-                expect(mesh.normals.length / 3).toBe(24);
+                expect(primitive.normals.length / 3).toBe(24);
-                expect(mesh.uvs.length / 2).toBe(24);
+                expect(primitive.uvs.length / 2).toBe(24);
                 expect(primitive.indices.length).toBe(36);
                 expect(primitive.material).toBe('Material');
             }), done).toResolve();
@@ -105,10 +105,10 @@ describe('loadObj', function() {
     it('loads obj with normals', function(done) {
         expect(loadObj(objNormalsPath, options)
             .then(function(data) {
-                var mesh = getMeshes(data)[0];
+                var primitive = getPrimitives(data)[0];
-                expect(mesh.positions.length / 3).toBe(24);
+                expect(primitive.positions.length / 3).toBe(24);
-                expect(mesh.normals.length / 3).toBe(24);
+                expect(primitive.normals.length / 3).toBe(24);
-                expect(mesh.uvs.length / 2).toBe(0);
+                expect(primitive.uvs.length / 2).toBe(0);
             }), done).toResolve();
     });
 
@@ -116,8 +116,8 @@ describe('loadObj', function() {
         expect(loadObj(objUnnormalizedPath, options)
             .then(function(data) {
                 var scratchNormal = new Cesium.Cartesian3();
-                var mesh = getMeshes(data)[0];
+                var primitive = getPrimitives(data)[0];
-                var normals = mesh.normals;
+                var normals = primitive.normals;
                 var normalsLength = normals.length / 3;
                 for (var i = 0; i < normalsLength; ++i) {
                     var normalX = normals.get(i * 3);
@@ -132,10 +132,10 @@ describe('loadObj', function() {
     it('loads obj with uvs', function(done) {
         expect(loadObj(objUvsPath, options)
             .then(function(data) {
-                var mesh = getMeshes(data)[0];
+                var primitive = getPrimitives(data)[0];
-                expect(mesh.positions.length / 3).toBe(20);
+                expect(primitive.positions.length / 3).toBe(20);
-                expect(mesh.normals.length / 3).toBe(0);
+                expect(primitive.normals.length / 3).toBe(0);
-                expect(mesh.uvs.length / 2).toBe(20);
+                expect(primitive.uvs.length / 2).toBe(20);
             }), done).toResolve();
     });
 
@@ -145,8 +145,8 @@ describe('loadObj', function() {
             loadObj(objNegativeIndicesPath, options)
         ])
             .then(function(results) {
-                var positionsReference = getMeshes(results[0])[0].positions.toFloatBuffer();
+                var positionsReference = getPrimitives(results[0])[0].positions.toFloatBuffer();
-                var positions = getMeshes(results[1])[0].positions.toFloatBuffer();
+                var positions = getPrimitives(results[1])[0].positions.toFloatBuffer();
                 expect(positions).toEqual(positionsReference);
             }), done).toResolve();
     });
@@ -154,9 +154,8 @@ describe('loadObj', function() {
     it('loads obj with triangle faces', function(done) {
         expect(loadObj(objTrianglesPath, options)
             .then(function(data) {
-                var mesh = getMeshes(data)[0];
                 var primitive = getPrimitives(data)[0];
-                expect(mesh.positions.length / 3).toBe(24);
+                expect(primitive.positions.length / 3).toBe(24);
                 expect(primitive.indices.length).toBe(36);
             }), done).toResolve();
     });
@@ -256,9 +255,8 @@ describe('loadObj', function() {
     it('loads obj with concave face containing 5 vertices', function(done) {
         expect(loadObj(objConcavePath, options)
             .then(function(data) {
-                var mesh = getMeshes(data)[0];
                 var primitive = getPrimitives(data)[0];
-                expect(mesh.positions.length / 3).toBe(30);
+                expect(primitive.positions.length / 3).toBe(30);
                 expect(primitive.indices.length).toBe(48);
             }), done).toResolve();
     });