add attribute name consts

README.md

@@ -118,8 +118,8 @@ doc.Meshes = []*gltf.Mesh{{
     Primitives: []*gltf.Primitive{{
         Indices: gltf.Index(modeler.WriteIndices(doc, []uint16{0, 1, 2})),
         Attributes: map[string]uint32{
-          "POSITION": modeler.WritePosition(doc, [][3]float32{{0, 0, 0}, {0, 10, 0}, {0, 0, 10}}),
-          "COLOR_0":  modeler.WriteColor(doc, [][3]uint8{{255, 0, 0}, {0, 255, 0}, {0, 0, 255}}),
+          gltf.POSITION: modeler.WritePosition(doc, [][3]float32{{0, 0, 0}, {0, 10, 0}, {0, 0, 10}}),
+          gltf.COLOR_0:  modeler.WriteColor(doc, [][3]uint8{{255, 0, 0}, {0, 255, 0}, {0, 0, 255}}),
         },
     }},
 }}

const.go

@@ -13,6 +13,18 @@ var (
 	DefaultTranslation = [3]float32{0, 0, 0}
 )
 
+// Attribute names defined in the spec.
+const (
+	POSITION   = "POSITION"
+	NORMAL     = "NORMAL"
+	TANGENT    = "TANGENT"
+	TEXCOORD_0 = "TEXCOORD_0"
+	TEXCOORD_1 = "TEXCOORD_1"
+	WEIGHTS_0  = "WEIGHTS_0"
+	JOINTS_0   = "JOINTS_0"
+	COLOR_0    = "COLOR_0"
+)
+
 var (
 	emptyMatrix   = [16]float32{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
 	emptyRotation = [4]float32{0, 0, 0, 0}

decoder_test.go

@@ -45,7 +45,7 @@ func TestOpen(t *testing.T) {
 			Buffers:   []*Buffer{{ByteLength: 1800, URI: "Cube.bin", Data: readFile("testdata/Cube/glTF/Cube.bin")}},
 			Images:    []*Image{{URI: "Cube_BaseColor.png"}, {URI: "Cube_MetallicRoughness.png"}},
 			Materials: []*Material{{Name: "Cube", AlphaMode: AlphaOpaque, AlphaCutoff: Float(0.5), PBRMetallicRoughness: &PBRMetallicRoughness{BaseColorFactor: &[4]float32{1, 1, 1, 1}, MetallicFactor: Float(1), RoughnessFactor: Float(1), BaseColorTexture: &TextureInfo{Index: 0}, MetallicRoughnessTexture: &TextureInfo{Index: 1}}}},
-			Meshes:    []*Mesh{{Name: "Cube", Primitives: []*Primitive{{Indices: Index(0), Material: Index(0), Mode: PrimitiveTriangles, Attributes: map[string]uint32{"NORMAL": 2, "POSITION": 1, "TANGENT": 3, "TEXCOORD_0": 4}}}}},
+			Meshes:    []*Mesh{{Name: "Cube", Primitives: []*Primitive{{Indices: Index(0), Material: Index(0), Mode: PrimitiveTriangles, Attributes: map[string]uint32{NORMAL: 2, POSITION: 1, TANGENT: 3, TEXCOORD_0: 4}}}}},
 			Nodes:     []*Node{{Mesh: Index(0), Name: "Cube", Matrix: [16]float32{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1}, Rotation: [4]float32{0, 0, 0, 1}, Scale: [3]float32{1, 1, 1}}},
 			Samplers:  []*Sampler{{WrapS: WrapRepeat, WrapT: WrapRepeat}},
 			Scene:     Index(0),
@@ -69,7 +69,7 @@ func TestOpen(t *testing.T) {
 				{Perspective: &Perspective{AspectRatio: Float(1.0), Yfov: 0.7, Zfar: Float(100), Znear: 0.01}},
 				{Orthographic: &Orthographic{Xmag: 1.0, Ymag: 1.0, Zfar: 100, Znear: 0.01}},
 			},
-			Meshes: []*Mesh{{Primitives: []*Primitive{{Indices: Index(0), Mode: PrimitiveTriangles, Attributes: map[string]uint32{"POSITION": 1}}}}},
+			Meshes: []*Mesh{{Primitives: []*Primitive{{Indices: Index(0), Mode: PrimitiveTriangles, Attributes: map[string]uint32{POSITION: 1}}}}},
 			Nodes: []*Node{
 				{Mesh: Index(0), Matrix: [16]float32{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1}, Rotation: [4]float32{-0.3, 0, 0, 0.9}, Scale: [3]float32{1, 1, 1}},
 				{Camera: Index(0), Matrix: [16]float32{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1}, Rotation: [4]float32{0, 0, 0, 1}, Scale: [3]float32{1, 1, 1}, Translation: [3]float32{0.5, 0.5, 3.0}},
@@ -96,7 +96,7 @@ func TestOpen(t *testing.T) {
 			},
 			Buffers:   []*Buffer{{ByteLength: 1224, Data: readFile("testdata/BoxVertexColors/glTF-Binary/BoxVertexColors.glb")[1628+20+8:]}},
 			Materials: []*Material{{Name: "Default", AlphaMode: AlphaOpaque, AlphaCutoff: Float(0.5), PBRMetallicRoughness: &PBRMetallicRoughness{BaseColorFactor: &[4]float32{0.8, 0.8, 0.8, 1}, MetallicFactor: Float(0.1), RoughnessFactor: Float(0.99)}}},
-			Meshes:    []*Mesh{{Name: "Cube", Primitives: []*Primitive{{Indices: Index(0), Material: Index(0), Mode: PrimitiveTriangles, Attributes: map[string]uint32{"POSITION": 1, "COLOR_0": 3, "NORMAL": 2, "TEXCOORD_0": 4}}}}},
+			Meshes:    []*Mesh{{Name: "Cube", Primitives: []*Primitive{{Indices: Index(0), Material: Index(0), Mode: PrimitiveTriangles, Attributes: map[string]uint32{POSITION: 1, COLOR_0: 3, NORMAL: 2, TEXCOORD_0: 4}}}}},
 			Nodes: []*Node{
 				{Name: "RootNode", Children: []uint32{1, 2, 3}, Matrix: [16]float32{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1}, Rotation: [4]float32{0, 0, 0, 1}, Scale: [3]float32{1, 1, 1}},
 				{Name: "Mesh", Matrix: [16]float32{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1}, Rotation: [4]float32{0, 0, 0, 1}, Scale: [3]float32{1, 1, 1}},

encode_test.go

@@ -152,8 +152,8 @@ func TestEncoder_Encode(t *testing.T) {
 		{"withMeshes", args{&Document{Meshes: []*Mesh{
 			{Extras: 8.0, Name: "mesh_1", Weights: []float32{1.2, 2}},
 			{Extras: 8.0, Name: "mesh_2", Primitives: []*Primitive{
-				{Extras: 8.0, Attributes: Attribute{"POSITION": 1}, Indices: Index(2), Material: Index(1), Mode: PrimitiveLines},
-				{Extras: 8.0, Targets: []Attribute{{"POSITION": 1, "THEN": 4}, {"OTHER": 2}}, Indices: Index(2), Material: Index(1), Mode: PrimitiveLines},
+				{Extras: 8.0, Attributes: Attribute{POSITION: 1}, Indices: Index(2), Material: Index(1), Mode: PrimitiveLines},
+				{Extras: 8.0, Targets: []Attribute{{POSITION: 1, "THEN": 4}, {"OTHER": 2}}, Indices: Index(2), Material: Index(1), Mode: PrimitiveLines},
 			}},
 		}}}, false},
 		{"withNodes", args{&Document{Nodes: []*Node{

example_test.go

@@ -36,7 +36,7 @@ func ExampleSave() {
 			Name: "Default", AlphaMode: gltf.AlphaOpaque, AlphaCutoff: gltf.Float(0.5),
 			PBRMetallicRoughness: &gltf.PBRMetallicRoughness{BaseColorFactor: &[4]float32{0.8, 0.8, 0.8, 1}, MetallicFactor: gltf.Float(0.1), RoughnessFactor: gltf.Float(0.99)},
 		}},
-		Meshes: []*gltf.Mesh{{Name: "Cube", Primitives: []*gltf.Primitive{{Indices: gltf.Index(0), Material: gltf.Index(0), Mode: gltf.PrimitiveTriangles, Attributes: map[string]uint32{"POSITION": 1, "COLOR_0": 3, "NORMAL": 2, "TEXCOORD_0": 4}}}}},
+		Meshes: []*gltf.Mesh{{Name: "Cube", Primitives: []*gltf.Primitive{{Indices: gltf.Index(0), Material: gltf.Index(0), Mode: gltf.PrimitiveTriangles, Attributes: map[string]uint32{gltf.POSITION: 1, gltf.COLOR_0: 3, gltf.NORMAL: 2, gltf.TEXCOORD_0: 4}}}}},
 		Nodes: []*gltf.Node{
 			{Name: "RootNode", Children: []uint32{1, 2, 3}},
 			{Name: "Mesh"},

modeler/example_test.go

@@ -16,8 +16,8 @@ func Example() {
 			{
 				Indices: gltf.Index(indicesAccessor),
 				Attributes: map[string]uint32{
-					"POSITION": positionAccessor,
-					"COLOR_0":  colorIndices,
+					gltf.POSITION: positionAccessor,
+					gltf.COLOR_0:  colorIndices,
 				},
 			},
 		},
@@ -42,8 +42,8 @@ func ExampleWriteAccessorsInterleaved() {
 			{
 				Indices: gltf.Index(indicesAccessor),
 				Attributes: map[string]uint32{
-					"POSITION": indices[0],
-					"COLOR_0":  indices[1],
+					gltf.POSITION: indices[0],
+					gltf.COLOR_0:  indices[1],
 				},
 			},
 		},

modeler/write.go

@@ -254,40 +254,40 @@ func WriteAttributesInterleaved(doc *gltf.Document, v Attributes) (map[string]ui
 		data  []interface{}
 	)
 	if len(v.Position) != 0 {
-		props = append(props, attrProps{Name: "POSITION"})
+		props = append(props, attrProps{Name: gltf.POSITION})
 		data = append(data, v.Position)
 	}
 	if len(v.Normal) != 0 {
-		props = append(props, attrProps{Name: "NORMAL"})
+		props = append(props, attrProps{Name: gltf.NORMAL})
 		data = append(data, v.Normal)
 	}
 	if len(v.Tangent) != 0 {
-		props = append(props, attrProps{Name: "TANGENT"})
+		props = append(props, attrProps{Name: gltf.TANGENT})
 		data = append(data, v.Tangent)
 	}
 	if sliceLength(v.TextureCoord_0) != 0 {
 		normalized := checkTextureCoord(v.TextureCoord_0)
-		props = append(props, attrProps{Name: "TEXCOORD_0", Normalized: normalized})
+		props = append(props, attrProps{Name: gltf.TEXCOORD_0, Normalized: normalized})
 		data = append(data, v.TextureCoord_0)
 	}
 	if sliceLength(v.TextureCoord_1) != 0 {
 		normalized := checkTextureCoord(v.TextureCoord_1)
-		props = append(props, attrProps{Name: "TEXCOORD_1", Normalized: normalized})
+		props = append(props, attrProps{Name: gltf.TEXCOORD_1, Normalized: normalized})
 		data = append(data, v.TextureCoord_1)
 	}
 	if sliceLength(v.Weights) != 0 {
 		normalized := checkWeights(v.Weights)
-		props = append(props, attrProps{Name: "WEIGHTS_0", Normalized: normalized})
+		props = append(props, attrProps{Name: gltf.WEIGHTS_0, Normalized: normalized})
 		data = append(data, v.Weights)
 	}
 	if sliceLength(v.Joints) != 0 {
 		checkJoints(v.Joints)
-		props = append(props, attrProps{Name: "JOINTS_0"})
+		props = append(props, attrProps{Name: gltf.JOINTS_0})
 		data = append(data, v.Joints)
 	}
 	if sliceLength(v.Color) != 0 {
 		normalized := checkColor(v.Color)
-		props = append(props, attrProps{Name: "COLOR_0", Normalized: normalized})
+		props = append(props, attrProps{Name: gltf.COLOR_0, Normalized: normalized})
 		data = append(data, v.Color)
 	}
 	for _, c := range v.CustomAttributes {
@@ -306,7 +306,7 @@ func WriteAttributesInterleaved(doc *gltf.Document, v Attributes) (map[string]ui
 		attrs[prop.Name] = index
 		doc.Accessors[index].Normalized = prop.Normalized
 	}
-	if pos, ok := attrs["POSITION"]; ok {
+	if pos, ok := attrs[gltf.POSITION]; ok {
 		min, max := minMaxFloat32(v.Position)
 		doc.Accessors[pos].Min = min[:]
 		doc.Accessors[pos].Max = max[:]

modeler/write_test.go

@@ -58,16 +58,16 @@ func TestWriteAttributesInterleaved(t *testing.T) {
 		t.Errorf("TestWriteAttributesInterleaved() accessors size = %v, want 10", len(doc.Accessors))
 	}
 	want := map[string]uint32{
-		"POSITION":   0,
-		"NORMAL":     1,
-		"TANGENT":    2,
-		"TEXCOORD_0": 3,
-		"TEXCOORD_1": 4,
-		"WEIGHTS_0":  5,
-		"JOINTS_0":   6,
-		"COLOR_0":    7,
-		"COLOR_1":    8,
-		"COLOR_2":    9,
+		gltf.POSITION:   0,
+		gltf.NORMAL:     1,
+		gltf.TANGENT:    2,
+		gltf.TEXCOORD_0: 3,
+		gltf.TEXCOORD_1: 4,
+		gltf.WEIGHTS_0:  5,
+		gltf.JOINTS_0:   6,
+		gltf.COLOR_0:    7,
+		"gltf.COLOR_1":  8,
+		"gltf.COLOR_2":  9,
 	}
 	if diff := deep.Equal(attrs, want); diff != nil {
 		t.Errorf("TestWriteAttributesInterleaved() = %v", diff)