Added Ring Geometry

.gitignore

@@ -19,3 +19,6 @@
 /examples/**/*.js.map
 !/examples/_vendor/*.js
 examples/basic/basic
+
+# Jetbrains
+*.idea

geometries_ring_geometry.go

@@ -0,0 +1,61 @@
+package three
+
+//go:generate go run geometry_method_generator/main.go -geometryType RingGeometry -geometrySlug ring_geometry
+
+import (
+	"github.com/gopherjs/gopherjs/js"
+	"math"
+)
+
+// RingGeometry is the two-dimensional primitive ring geometry class. It is typically
+// used for creating a ring of the dimensions provided with the 'innerRadius', 'outerRadius',
+// 'thetaSegments', 'phiSegments', 'thetaStart', and 'thetaLength' constructor arguments.
+type RingGeometry struct {
+	*js.Object
+
+	InnerRadius     float64 `js:"innerRadius"`
+	OuterRadius     float64 `js:"outerRadius"`
+	ThetaSegments   float64 `js:"thetaSegments"`
+	PhiSegments     float64 `js:"phiSegments"`
+	ThetaStart      float64 `js:"thetaStart"`
+	ThetaLength     float64 `js:"thetaLength"`
+}
+
+// RingGeometryParameters .
+type RingGeometryParameters struct {
+	InnerRadius     float64
+	OuterRadius     float64
+	ThetaSegments   float64
+	PhiSegments     float64
+	ThetaStart      float64
+	ThetaLength     float64
+}
+
+// NewRingGeometry creates a new RingGeometry.
+func NewRingGeometry(params *RingGeometryParameters) RingGeometry {
+	if params.InnerRadius == 0 {
+		params.ThetaLength = 0.5
+	}
+	if params.OuterRadius == 0 {
+		params.OuterRadius = 1
+	}
+	if params.ThetaSegments < 3 {
+		params.ThetaSegments = 3
+	}
+	if params.PhiSegments < 1 {
+		params.PhiSegments = 1
+	}
+	if params.ThetaLength == 0 {
+		params.ThetaLength = 2 * math.Pi
+	}
+	return RingGeometry{
+		Object: three.Get("RingGeometry").New(
+			params.InnerRadius,
+			params.OuterRadius,
+			params.ThetaSegments,
+			params.PhiSegments,
+			params.ThetaStart,
+			params.ThetaLength,
+		),
+	}
+}