Kinect.KinectManager.UpdateUserHistogramImage C# (CSharp) Method

        void UpdateUserHistogramImage()
        {
            int numOfPoints = 0;
            Array.Clear(usersHistogramMap, 0, usersHistogramMap.Length);

            // Calculate cumulative histogram for depth
            for (int i = 0; i < usersMapSize; i++)
            {
                // Only calculate for depth that contains users
                if (sensorData.bodyIndexImage[i] != 255)
                {
                    ushort depth = sensorData.depthImage[i];
                    if (depth > 5000)
                        depth = 5000;

                    usersHistogramMap[depth]++;
                    numOfPoints++;
                }
            }

            if (numOfPoints > 0)
            {
                for (int i = 1; i < usersHistogramMap.Length; i++)
                {
                    usersHistogramMap[i] += usersHistogramMap[i - 1];
                }

                for (int i = 0; i < usersHistogramMap.Length; i++)
                {
                    usersHistogramMap[i] = 1.0f - (usersHistogramMap[i] / numOfPoints);
                }
            }

            List<int> alTrackedIndexes = new List<int>(dictUserIdToIndex.Values);
            byte btSelBI = sensorData.selectedBodyIndex;
            Color32 clrClear = Color.clear;

            // Create the actual users texture based on label map and depth histogram
            for (int i = 0; i < usersMapSize; i++)
            {
                ushort userMap = sensorData.bodyIndexImage[i];
                ushort userDepth = sensorData.depthImage[i];

                if (userDepth > 5000)
                    userDepth = 5000;

                ushort nowUserPixel = userMap != 255 ? (ushort)((userMap << 13) | userDepth) : userDepth;
                ushort wasUserPixel = usersPrevState[i];

                // draw only the changed pixels
                if (nowUserPixel != wasUserPixel)
                {
                    usersPrevState[i] = nowUserPixel;

                    bool bUserTracked = btSelBI != 255 ? btSelBI == (byte)userMap :
                        (bLimitedUsers ? alTrackedIndexes.Contains(userMap) : userMap != 255);

                    if (!bUserTracked)
                    {
                        usersHistogramImage[i] = clrClear;
                    }
                    else
                    {
                        if (sensorData.colorImage != null)
                        {
                            Vector2 vColorPos = Vector2.zero;

                            if (sensorData.depth2ColorCoords != null)
                            {
                                vColorPos = sensorData.depth2ColorCoords[i];
                            }
                            else
                            {
                                Vector2 vDepthPos = Vector2.zero;
                                vDepthPos.x = i % sensorData.depthImageWidth;
                                vDepthPos.y = i / sensorData.depthImageWidth;

                                vColorPos = KinectInterop.MapDepthPointToColorCoords(sensorData, vDepthPos, userDepth);
                            }

                            if (!float.IsInfinity(vColorPos.x) && !float.IsInfinity(vColorPos.y))
                            {
                                int cx = (int)vColorPos.x;
                                int cy = (int)vColorPos.y;
                                int colorIndex = cx + cy * sensorData.colorImageWidth;

                                if (colorIndex >= 0 && colorIndex < usersClrSize)
                                {
                                    int ci = colorIndex << 2;
                                    Color32 colorPixel = new Color32(sensorData.colorImage[ci], sensorData.colorImage[ci + 1], sensorData.colorImage[ci + 2], 255);

                                    usersHistogramImage[i] = colorPixel;
                                }
                            }
                        }
                        else
                        {
                            // Create a blending color based on the depth histogram
                            float histDepth = usersHistogramMap[userDepth];
                            Color c = new Color(histDepth, histDepth, histDepth, 0.9f);

                            switch (userMap % 4)
                            {
                                case 0:
                                    usersHistogramImage[i] = Color.red * c;
                                    break;
                                case 1:
                                    usersHistogramImage[i] = Color.green * c;
                                    break;
                                case 2:
                                    usersHistogramImage[i] = Color.blue * c;
                                    break;
                                case 3:
                                    usersHistogramImage[i] = Color.magenta * c;
                                    break;
                            }
                        }
                    }

                }
            }

        }