Looking for example for plotting Volumetric Slice in Ilnumerics

Question

is there any example for plotting volumetric slice in Ilnumerics use community version. This is an example I got from matlab website:

Volumetric slice image example of matlab

I have array X, Y, Z as posistions and V (velocity) as value for color plotting. All I have done is use Ilpoints to plot that V in position X, Y, Z not , a surfaces. Here are My Code and the result,

ILArray<float> plotXY = ILMath.zeros<float>(3, XcoordinateXY.Length);
        plotXY["0;:"] = ILMath.tosingle(SurfaceXY[":;:;1"]);
        plotXY["1;:"] = ILMath.tosingle(SurfaceXY[":;:;2"]);
        plotXY["2;:"] = ILMath.tosingle(SurfaceXY[":;:;3"]);

        ILArray<float> ColorMap = ILMath.tosingle(SurfaceXY[":;:;0"]);

var ilsurfaceplotXY = new ILPoints()
        {

            /*Wireframe = { Color = Color.FromArgb(50, Color.LightGray) },
            Colormap = new ILColormap(dataXY),
            Children = { new ILColorbar() }*/
            Positions = plotXY,
            Colors = cm.Map(ColorMap).T,
            Color = null
        };

Here are code for displaying:

 var scene = new ILScene();
        scene.Add(
                new ILPlotCube
                {
                    TwoDMode = false,
                    Axes =
                    {

                        XAxis =
                        {
                            Label = { Text = "UTM X (Km)" },
                            GridMajor =
                            {
                                DashStyle = DashStyle.Dashed,
                                Color = Color.DarkGray,
                                Width = 1

                            }
                        },
                        YAxis =
                        {
                            Label = { Text = "UTM Y (Km)" },
                            GridMajor =
                            {
                                DashStyle = DashStyle.Dashed,
                                Color = Color.DarkGray,
                                Width = 1
                            }
                        },
                        ZAxis =
                        {
                            Label = { Text = "DEPTH (Km)" },
                            GridMajor =
                            {
                                DashStyle = DashStyle.Dashed,
                                Color = Color.DarkGray,
                                Width = 1
                            }
                        }
                    },

                    Children = { ilsurfaceplotXY, ilsurfaceplotXZ, ilsurfaceplotYZ },
                }
            );

        this.ilPanel1.Scene = scene;
        this.ilPanel1.Scene.Configure(); 
        this.ilPanel1.Refresh();

And here is an image result.

Result Image

I'm sorry the image is in the link.

Answer 1

Regarding the visualization this can be done with regular surfaces, imagesc plots, or the new fast surface in the Drawing2 toolbox. They all allow to provide X,Y, and Z values as well as a color for each grid point or tile.

Regarding the computation of the points: it seems that you just pick points from the available set. It would be much better to interpolate between these points. The Interpolation Toolbox provides functions for the interpolation of gridded and scattered data. (In your case the data seem to be gridded ?). This allows to have slices in arbitrary orientation / angles. The interpolation toolbox interpolates the positions of the slice grid points as well as the values for the colors.

From an online example:

The setup of the horizontal slices is done as follows:

ILArray<float> C; 
for (int i = 0; i < m_nrSlices; i += m_nrSlices / 4) {
    C = m_V[":",":", i];
    pc1.Add(new ILSurface(grid + i, C, colormap: Colormaps.Bone) 
    { 
        Wireframe = { Visible = false },
    });

}

Here, m_V is your 3D dataset, handled as 3D array. pc is the plot cube. The surfaces are simply added to the plot cube. The points of the red interpolated area are dynamically computed as the user moves the red balls:

// Points on the cutting area are considered scattered points, because the area is not (necessarily) plain. However, V 
// is a grid. interp3s interpolates the scattered points very efficiently. 
// Note how the shape of the coordinate arrays Xn, Yn and Zn is not important. interp3s takes their elements in sequential order. 
// The output is a vector of interpolated values. (We gonna reshape it below.)
ILArray < float> Z = Interpolation.interp3s(m_V, m_x, m_x, m_x, m_Xn, m_Yn, Zn, method: InterpolationMethod.cubic);

// let's plot! We get a reference to the fast surface
var fsurf = ilPanel1.Scene.First<ILFastSurface>("dynslice"); 
if (fsurf != null) {
    // first time setup only: provide the full coordinates of X and V. Here it is sufficient to provide grid vectors. 
    if (fsurf.Cols == 0) {
        fsurf.Update(X: m_xn * res, Y: m_xn * res, Z: Zn * res, C: ILMath.reshape(Z, Zn.S), colormap: Colormaps.Hot);
    } else {
        // the grid was configured already and did not change. we save some recomputing by ommiting the X and Y coordinates, prevent from reshaping buffers.
        fsurf.Update(Z: Zn * res, C: ILMath.reshape(Z, Zn.S), colormap: Colormaps.Hot);
    }
}
fsurf.Configure();
ilPanel1.Refresh(); 

To go into the details is out of scope for SO. You can download the example and run it on your machine. You will need a recent version of ILNumerics though.

EDIT: Axis aligned slices as in the plot you provided are only a subdomain, of course. Generating them works in the very same way: