예제 #1
0
        /// <summary>
        /// Automatically computes bounding box for the specified vertex arrays.
        /// </summary>
        /// <param name="vertexArrayObject">
        ///
        /// </param>
        /// <returns>
        /// It returns the <see cref="IBoundingVolume"/> for <paramref name="vertexArrayObject"/>, if possible.
        /// </returns>
        private static IBoundingVolume ComputeBoundingVolume(VertexArrayObject vertexArrayObject)
        {
            if (vertexArrayObject == null)
            {
                throw new ArgumentNullException("vertexArrayObject");
            }

            VertexArrayObject.IVertexArray vertexArray = vertexArrayObject.GetVertexArray(VertexArraySemantic.Position);
            if (vertexArray == null)
            {
                return(null);
            }

            ArrayBufferObjectBase positionArray = vertexArray.Array;
            Type positionArrayType = positionArray.GetType();

            if (positionArrayType == typeof(ArrayBufferObject <Vertex4f>))
            {
                ArrayBufferObject <Vertex4f> positionArray4f = (ArrayBufferObject <Vertex4f>)positionArray;
                Vertex4f min = Vertex4f.Maximum, max = Vertex4f.Minimum;
                positionArray4f.MinMax(out min, out max);

                return(new BoundingBox((Vertex3f)min, (Vertex3f)max));
            }
            else if (positionArrayType == typeof(ArrayBufferObject <Vertex3f>))
            {
                ArrayBufferObject <Vertex3f> positionArray3f = (ArrayBufferObject <Vertex3f>)positionArray;
                Vertex3f min = Vertex3f.Maximum, max = Vertex3f.Minimum;
                positionArray3f.MinMax(out min, out max);

                return(new BoundingBox(min, max));
            }
            else
            {
                return(null);
            }
        }