Ring.qml Example File | Qt 3D 5.12.9

- Qt 5.12
- Qt 3D
- Qt 3D: Planets QML Example
- Ring.qml Example File
- Qt 5.12.9 Reference Documentation

# Ring.qml Example File

planets-qml/Ring.qml

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     import Qt3D.Render 2.0

     // TODO: Once support for meshes from arrays is implemented, replace ring.obj with that
     Mesh {
         property real innerRadius
         property real outerRadius
         /*
         property real ringSegments

         property var vertices: []
         property var faces: []
         property var faceVertexUvs: []
         */

         source: "qrc:/meshes/ring.obj"

         // Converted from the _RingGeometry() method in the threex.planets.js extension.
         /*
         function makeRing() {
             innerRadius = innerRadius || 0
             outerRadius = outerRadius || 50
             var thetaSegments = ringSegments || 8
             console.log(innerRadius + "," + outerRadius + "," + thetaSegments)

             var normal = Qt.vector3d(0, 0, 1)

             for (var i = 0; i < thetaSegments; i++) {
                 var angleLo = (i / thetaSegments) * Math.PI * 2
                 var angleHi = ((i + 1) / thetaSegments) * Math.PI * 2

                 var vertex1 = Qt.vector3d(innerRadius * Math.cos(angleLo),
                                           innerRadius * Math.sin(angleLo),
                                           0)
                 var vertex2 = Qt.vector3d(outerRadius * Math.cos(angleLo),
                                           outerRadius * Math.sin(angleLo),
                                           0)
                 var vertex3 = Qt.vector3d(innerRadius * Math.cos(angleHi),
                                           innerRadius * Math.sin(angleHi),
                                           0)
                 var vertex4 = Qt.vector3d(outerRadius * Math.cos(angleHi),
                                           outerRadius * Math.sin(angleHi),
                                           0)

                 vertices.push(vertex1)
                 vertices.push(vertex2)
                 vertices.push(vertex3)
                 vertices.push(vertex4)

                 var vertexIdx = i * 4

                 // Create the first triangle
                 var face = Qt.vector4d(vertexIdx + 0, vertexIdx + 1, vertexIdx + 2, normal)
                 var uvs = []

                 var uv = Qt.vector2d(0, 0)
                 uvs.push(uv)
                 uv = Qt.vector2d(1, 0)
                 uvs.push(uv)
                 uv = Qt.vector2d(0, 1)
                 uvs.push(uv)

                 faces.push(face)
                 //faceVertexUvs[0].push(uvs)
                 faceVertexUvs.push(uvs)

                 // Create the second triangle
                 face = Qt.vector4d(vertexIdx + 2, vertexIdx + 1, vertexIdx + 3, normal)
                 uvs = []

                 uv = Qt.vector2d(0, 1)
                 uvs.push(uv)
                 uv = Qt.vector2d(1, 0)
                 uvs.push(uv)
                 uv = Qt.vector2d(1, 1)
                 uvs.push(uv)

                 faces.push(face)
                 //faceVertexUvs[0].push(uvs)
                 faceVertexUvs.push(uvs)
             }

             computeFaceNormals()
         }

         // Converted from the computeFaceNormals() method in the three.js extension.
         function computeFaceNormals() {
             var cb = Qt.vector3d(0, 0, 0)
             var ab = Qt.vector3d(0, 0, 0)

             for (var f = 0, fl = faces.length; f < fl; f ++) {
                 var face = faces[f]

                 var vA = vertices[face.x]
                 var vB = vertices[face.y]
                 var vC = vertices[face.z]

                 cb = vC.minus(vB)
                 ab = vA.minus(vB)
                 cb = cb.crossProduct(ab)

                 cb = cb.normalized()

                 face.w = cb
             }
         }
         */
     }