コード例 #1
0
        /// <summary>
        /// Creates a transfer function from RGB and alpha cubic splines.
        /// </summary>
        /// <param name="tcp">Transfer control points to use.</param>
        /// <returns>An array of RGBA colors corresponding to each isovalue 0-255.</returns>
        public static Color[] CreateTransferFunction(TransferControlPoints tcp)
        {
            Debug.Assert(tcp.rgbPoints.Count == tcp.rgbIsoValues.Count);
            Debug.Assert(tcp.alphaPoints.Count == tcp.alphaIsoValues.Count);
            Debug.Assert(tcp.rgbIsoValues[0] == 0 && tcp.rgbIsoValues[tcp.rgbIsoValues.Count - 1] == 255,
                         "The first and last isovalues must be 0 and 255, respectively.");
            Debug.Assert(tcp.alphaIsoValues[0] == 0 && tcp.alphaIsoValues[tcp.alphaIsoValues.Count - 1] == 255,
                         "The first and last isovalues must be 0 and 255, respectively.");

            // Calculate the cubic splines for the RGB and alpha values.
            CubicSpline <Cubic3> rgbSpline   = new CubicSpline <Cubic3>();
            CubicSpline <Cubic1> alphaSpline = new CubicSpline <Cubic1>();

            rgbSpline.Calculate(tcp.rgbPoints);
            alphaSpline.Calculate(tcp.alphaPoints);

            // Create the transfer function from the two splines.
            Color[] transferFunc = new Color[256];

            // ...RGB portion.
            int index = 0;

            for (int i = 0; i < rgbSpline.Count; ++i)
            {
                int interval = tcp.rgbIsoValues[i + 1] - tcp.rgbIsoValues[i];
                Debug.Assert(interval > 0, "Isovalues must be incremental by at least 1/increment.");

                // Fill in the color at the isovalues covered by the current spline segment.
                for (int j = 0; j < interval; ++j)
                {
                    float position = j / (float)interval;
                    transferFunc[index++] = rgbSpline.GetPointOnSpline(i, position).ToColor();
                }
            }
            transferFunc[index] = rgbSpline.GetPointOnSpline(rgbSpline.Count - 1, 1f).ToColor();

            // ...alpha portion.
            index = 0;
            for (int i = 0; i < alphaSpline.Count; ++i)
            {
                int interval = tcp.alphaIsoValues[i + 1] - tcp.alphaIsoValues[i];
                Debug.Assert(interval > 0, "Isovalues must be incremental by at least 1/increment.");

                // Fill in the alpha at the isovalues covered by the current spline segment.
                for (int j = 0; j < interval; ++j)
                {
                    float position = j / (float)interval;
                    transferFunc[index++].A = alphaSpline.GetPointOnSpline(i, position).ToByte();
                }
            }
            transferFunc[index].A = alphaSpline.GetPointOnSpline(alphaSpline.Count - 1, 1f).ToByte();

            return(transferFunc);
        }
コード例 #2
0
        /// <summary>
        /// Creates a transfer function from RGB and alpha cubic splines.
        /// </summary>
        /// <param name="tcp">Transfer control points to use.</param>
        /// <returns>An array of RGBA colors corresponding to each isovalue 0-255.</returns>
        public static Color[] CreateTransferFunction(TransferControlPoints tcp)
        {
            Debug.Assert(tcp.rgbPoints.Count == tcp.rgbIsoValues.Count);
            Debug.Assert(tcp.alphaPoints.Count == tcp.alphaIsoValues.Count);
            Debug.Assert(tcp.rgbIsoValues[0] == 0 && tcp.rgbIsoValues[tcp.rgbIsoValues.Count - 1] == 255,
                "The first and last isovalues must be 0 and 255, respectively.");
            Debug.Assert(tcp.alphaIsoValues[0] == 0 && tcp.alphaIsoValues[tcp.alphaIsoValues.Count - 1] == 255,
                "The first and last isovalues must be 0 and 255, respectively.");

            // Calculate the cubic splines for the RGB and alpha values.
            CubicSpline<Cubic3> rgbSpline = new CubicSpline<Cubic3>();
            CubicSpline<Cubic1> alphaSpline = new CubicSpline<Cubic1>();
            rgbSpline.Calculate(tcp.rgbPoints);
            alphaSpline.Calculate(tcp.alphaPoints);

            // Create the transfer function from the two splines.
            Color[] transferFunc = new Color[256];

            // ...RGB portion.
            int index = 0;
            for (int i = 0; i < rgbSpline.Count; ++i)
            {
                int interval = tcp.rgbIsoValues[i + 1] - tcp.rgbIsoValues[i];
                Debug.Assert(interval > 0, "Isovalues must be incremental by at least 1/increment.");

                // Fill in the color at the isovalues covered by the current spline segment.
                for (int j = 0; j < interval; ++j)
                {
                    float position = j / (float)interval;
                    transferFunc[index++] = rgbSpline.GetPointOnSpline(i, position).ToColor();
                }
            }
            transferFunc[index] = rgbSpline.GetPointOnSpline(rgbSpline.Count - 1, 1f).ToColor();

            // ...alpha portion.
            index = 0;
            for (int i = 0; i < alphaSpline.Count; ++i)
            {
                int interval = tcp.alphaIsoValues[i + 1] - tcp.alphaIsoValues[i];
                Debug.Assert(interval > 0, "Isovalues must be incremental by at least 1/increment.");

                // Fill in the alpha at the isovalues covered by the current spline segment.
                for (int j = 0; j < interval; ++j)
                {
                    float position = j / (float)interval;
                    transferFunc[index++].A = alphaSpline.GetPointOnSpline(i, position).ToByte();
                }
            }
            transferFunc[index].A = alphaSpline.GetPointOnSpline(alphaSpline.Count - 1, 1f).ToByte();

            return transferFunc;
        }