Bit optimized version of particle draw loop for delta engine

deltaengine_particledraw.cs

        private VertexPositionColorTextured[] _vertices = new VertexPositionColorTextured[4 * 1000];
        private short[] _indices = new short[6 * 1000];

        public virtual void Draw(Time gameTime, Drawing drawing)
        {
            int pc = particles.Count;
            if (_vertices.Length < (4 * pc) || _indices.Length < (6 * pc))
            {
                _vertices = new VertexPositionColorTextured[4 * pc];
                _indices = new short[6 * pc];
            }

            Particle p; 
            var indicesIndex = 0;
            var quadIndex = 0;
            for (int i = 0; i < pc; i++, quadIndex+=4)
            {
                p = particles[i];
                _vertices[quadIndex] = new VertexPositionColorTextured(
                    Rotate(p.DrawArea.TopLeft, p), p.Color, Point.Zero);
                _vertices[quadIndex + 1] = new VertexPositionColorTextured(
                    Rotate(p.DrawArea.TopRight, p), p.Color, Point.UnitX);
                _vertices[quadIndex + 2] = new VertexPositionColorTextured(
                    Rotate(p.DrawArea.BottomRight, p), p.Color, Point.One);
                _vertices[quadIndex + 3] = new VertexPositionColorTextured(
                    Rotate(p.DrawArea.BottomLeft, p), p.Color, Point.UnitY);

                _indices[indicesIndex++] = (short)quadIndex;
                _indices[indicesIndex++] = (short)(quadIndex + 1);
                _indices[indicesIndex++] = (short)(quadIndex + 2);
                _indices[indicesIndex++] = (short)quadIndex;
                _indices[indicesIndex++] = (short)(quadIndex + 2);
                _indices[indicesIndex++] = (short)(quadIndex + 3);
            }

            foreach (Image img in textures)
            {
                img.Draw(new VertexPositionColorTextured[4]);
            }

            drawing.SetIndices(_indices, indicesIndex);
            drawing.DrawVertices(VerticesMode.Triangles, _vertices);
        }

  	protected Point Rotate(Point point, Particle particle)
		{
			var rotationCenter = particle.DrawArea.Center;
			point -= rotationCenter;
			float sin = MathFunctions.Sin(particle.Rotation);
			float cos = MathFunctions.Cos(particle.Rotation);
			point = new Point(point.X * cos - point.Y * sin, point.X * sin + point.Y * cos);
			return rotationCenter + point;
		}