/*******************************************************************************/
/*
* File name: MCal.cpp
* Location:  ...\Matrox Imaging\MILxxx\Examples\General\Mcal\C++
 *             
*
* Synopsis:  This program uses the Calibration module to calibrate a high
*            distortion camera with an image of a grid. Then, an image of
*            a board grabbed with the same camera is loaded and some
*            measurements are done in real world calibrated units. Finally
*            the distorted board image is corrected using the same camera
*            calibration.
*
* Printable calibration grids in PDF format can be found in your
* "Matrox Imaging/Images/" directory.
*
* Copyright (C) Matrox Electronic Systems Ltd., 1992-2015.
* All Rights Reserved
*/
#include <mil.h>

/* Example selection. */
#define RUN_LINEAR_CALIBRATION_EXAMPLE     M_YES
#define RUN_TSAI_CALIBRATION_EXAMPLE       M_YES

/* Example functions declarations. */  
void LinearInterpolationCalibration(MIL_ID MilSystem, MIL_ID MilDisplay);
void TsaiCalibration(MIL_ID MilSystem, MIL_ID MilDisplay);

/*  Main function. */
int MosMain(void)
   {
   MIL_ID MilApplication, /* Application identifier. */
          MilSystem,      /* System Identifier.      */
          MilDisplay;     /* Display identifier.     */

   /* Allocate defaults. */
   MappAllocDefault(M_DEFAULT, &MilApplication, &MilSystem, &MilDisplay, M_NULL, M_NULL);

   /* Print module name. */
   MosPrintf(MIL_TEXT("CALIBRATION MODULE:\n"));
   MosPrintf(MIL_TEXT("-------------------\n\n"));

#if (RUN_LINEAR_CALIBRATION_EXAMPLE)
   LinearInterpolationCalibration(MilSystem, MilDisplay);
#endif

#if (RUN_TSAI_CALIBRATION_EXAMPLE)
   TsaiCalibration(MilSystem, MilDisplay);
#endif

   /* Free defaults. */    
   MappFreeDefault(MilApplication, MilSystem, MilDisplay, M_NULL, M_NULL);

   return 0;
   }

/*****************************************************************************
Linear interpolation example. 
*****************************************************************************/
/* Source image files specification. */
#define GRID_IMAGE_FILE        M_IMAGE_PATH MIL_TEXT("CalGrid.mim")
#define BOARD_IMAGE_FILE       M_IMAGE_PATH MIL_TEXT("CalBoard.mim")

/* World description of the calibration grid. */
#define GRID_OFFSET_X          0
#define GRID_OFFSET_Y          0
#define GRID_OFFSET_Z          0
#define GRID_ROW_SPACING       1
#define GRID_COLUMN_SPACING    1
#define GRID_ROW_NUMBER       18
#define GRID_COLUMN_NUMBER    25

/* Measurement boxes specification. */
#define MEAS_BOX_POS_X1       55
#define MEAS_BOX_POS_Y1       24
#define MEAS_BOX_WIDTH1        7
#define MEAS_BOX_HEIGHT1     425

#define MEAS_BOX_POS_X2      225
#define MEAS_BOX_POS_Y2       11
#define MEAS_BOX_WIDTH2        7
#define MEAS_BOX_HEIGHT2     450

/* Specification of the stripes' constraints. */
#define WIDTH_APPROXIMATION  410
#define WIDTH_VARIATION       25
#define MIN_EDGE_VALUE     5

void LinearInterpolationCalibration(MIL_ID MilSystem, MIL_ID MilDisplay)
   {
   MIL_ID  MilImage,          /* Image buffer identifier.       */
           MilOverlayImage,   /* Overlay image.                 */
           MilCalibration,    /* Calibration identifier.        */
           MeasMarker1,       /* Measurement marker identifier. */
           MeasMarker2;       /* Measurement marker identifier. */
   MIL_DOUBLE  WorldDistance1,  WorldDistance2;
   MIL_DOUBLE  PixelDistance1,  PixelDistance2;
   MIL_DOUBLE  PosX1, PosY1, PosX2, PosY2, PosX3, PosY3, PosX4, PosY4;
   MIL_INT     CalibrationStatus;

   /* Clear the display */
   MdispControl(MilDisplay, M_OVERLAY_CLEAR, M_DEFAULT);

   /* Restore source image into an automatically allocated image buffer. */
   MbufRestore(GRID_IMAGE_FILE, MilSystem, &MilImage);

   /* Display the image buffer. */
   MdispSelect(MilDisplay, MilImage);

   /* Prepare for overlay annotation. */
   MdispControl(MilDisplay, M_OVERLAY, M_ENABLE);
   MdispInquire(MilDisplay, M_OVERLAY_ID, &MilOverlayImage);

   /* Pause to show the original image. */
   MosPrintf(MIL_TEXT("\nLINEAR INTERPOLATION CALIBRATION:\n"));
   MosPrintf(MIL_TEXT("------------\n\n"));
   MosPrintf(MIL_TEXT("The displayed grid has been grabbed with a high distortion\n"));
   MosPrintf(MIL_TEXT("camera and will be used to calibrate the camera.\n"));
   MosPrintf(MIL_TEXT("Press <Enter> to continue.\n\n"));
   MosGetch();

   /* Allocate a camera calibration context. */
   McalAlloc(MilSystem, M_DEFAULT, M_DEFAULT, &MilCalibration);

   /* Calibrate the camera with the image of the grid and its world description. */
   McalGrid(MilCalibration, MilImage,
            GRID_OFFSET_X, GRID_OFFSET_Y, GRID_OFFSET_Z,
            GRID_ROW_NUMBER, GRID_COLUMN_NUMBER,
            GRID_ROW_SPACING, GRID_COLUMN_SPACING,
            M_DEFAULT, M_DEFAULT);

   McalInquire(MilCalibration, M_CALIBRATION_STATUS + M_TYPE_MIL_INT, &CalibrationStatus);
   if( CalibrationStatus == M_CALIBRATED )
      {
      /* Perform a first image transformation with the calibration grid. */
      McalTransformImage(MilImage, MilImage, MilCalibration,
                         M_BILINEAR + M_OVERSCAN_CLEAR, M_DEFAULT, M_DEFAULT);

      /* Pause to show the corrected image of the grid. */
      MosPrintf(MIL_TEXT("The camera has been calibrated and the image of the grid\n"));
      MosPrintf(MIL_TEXT("has been transformed to remove its distortions.\n"));
      MosPrintf(MIL_TEXT("Press <Enter> to continue.\n\n"));
      MosGetch();

      /* Read the image of the board and associate the calibration to the image. */
      MbufLoad(BOARD_IMAGE_FILE, MilImage);
      McalAssociate(MilCalibration, MilImage, M_DEFAULT);

      /* Allocate the measurement markers. */
      MmeasAllocMarker(MilSystem, M_STRIPE, M_DEFAULT, &MeasMarker1);
      MmeasAllocMarker(MilSystem, M_STRIPE, M_DEFAULT, &MeasMarker2);

      /* Set the markers' measurement search region. */
      MmeasSetMarker(MeasMarker1, M_BOX_ORIGIN, MEAS_BOX_POS_X1, MEAS_BOX_POS_Y1);
      MmeasSetMarker(MeasMarker1, M_BOX_SIZE, MEAS_BOX_WIDTH1, MEAS_BOX_HEIGHT1);
      MmeasSetMarker(MeasMarker2, M_BOX_ORIGIN, MEAS_BOX_POS_X2, MEAS_BOX_POS_Y2);
      MmeasSetMarker(MeasMarker2, M_BOX_SIZE, MEAS_BOX_WIDTH2, MEAS_BOX_HEIGHT2);

      /* Set markers' orientation. */
      MmeasSetMarker(MeasMarker1, M_ORIENTATION, M_HORIZONTAL, M_NULL);
      MmeasSetMarker(MeasMarker2, M_ORIENTATION, M_HORIZONTAL, M_NULL);

      /* Set markers' settings to locate the largest stripe within the range
         [WIDTH_APPROXIMATION - WIDTH_VARIATION,
          WIDTH_APPROXIMATION + WIDTH_VARIATION],
         and with an edge strength over MIN_EDGE_VALUE. */
      MmeasSetMarker(MeasMarker1, M_EDGEVALUE_MIN, MIN_EDGE_VALUE, M_NULL);

      /* Remove the default strength characteristic score mapping. */
      MmeasSetScore(MeasMarker1, M_STRENGTH_SCORE,
                                 0.0,
                                 0.0,
                                 M_MAX_POSSIBLE_VALUE,
                                 M_MAX_POSSIBLE_VALUE,
                                 M_DEFAULT,
                                 M_DEFAULT,
                                 M_DEFAULT);

      /* Add a width characteristic score mapping (increasing ramp)
         to find the largest stripe within a given range.

         Width score mapping to find the largest stripe within a given
         width range ]Wmin, Wmax]:

            Score
               ^
               |         /|
               |       /  |
               |     /    |
               +---------------> Width
                   Wmin  Wmax
      */
      MmeasSetScore(MeasMarker1, M_STRIPE_WIDTH_SCORE,
                                 WIDTH_APPROXIMATION - WIDTH_VARIATION,
                                 WIDTH_APPROXIMATION + WIDTH_VARIATION,
                                 WIDTH_APPROXIMATION + WIDTH_VARIATION,
                                 WIDTH_APPROXIMATION + WIDTH_VARIATION,
                                 M_DEFAULT,
                                 M_PIXEL,
                                 M_DEFAULT);

      /* Set the same settings for the second marker. */
      MmeasSetMarker(MeasMarker2, M_EDGEVALUE_MIN, MIN_EDGE_VALUE, M_NULL);

      MmeasSetScore(MeasMarker2, M_STRENGTH_SCORE,
                                 0.0,
                                 0.0,
                                 M_MAX_POSSIBLE_VALUE,
                                 M_MAX_POSSIBLE_VALUE,
                                 M_DEFAULT,
                                 M_DEFAULT,
                                 M_DEFAULT);

      MmeasSetScore(MeasMarker2, M_STRIPE_WIDTH_SCORE,
                                 WIDTH_APPROXIMATION - WIDTH_VARIATION,
                                 WIDTH_APPROXIMATION + WIDTH_VARIATION,
                                 WIDTH_APPROXIMATION + WIDTH_VARIATION,
                                 WIDTH_APPROXIMATION + WIDTH_VARIATION,
                                 M_DEFAULT,
                                 M_PIXEL,
                                 M_DEFAULT);

      /* Find and measure the position and width of the board. */
      MmeasFindMarker(M_DEFAULT, MilImage, MeasMarker1, M_STRIPE_WIDTH+M_POSITION);
      MmeasFindMarker(M_DEFAULT, MilImage, MeasMarker2, M_STRIPE_WIDTH+M_POSITION);

      /* Get the world width of the two markers. */
      MmeasGetResult(MeasMarker1, M_STRIPE_WIDTH, &WorldDistance1, M_NULL);
      MmeasGetResult(MeasMarker2, M_STRIPE_WIDTH, &WorldDistance2, M_NULL);

      /* Get the pixel width of the two markers. */
      MmeasSetMarker(MeasMarker1, M_RESULT_OUTPUT_UNITS, M_PIXEL, M_NULL);
      MmeasSetMarker(MeasMarker2, M_RESULT_OUTPUT_UNITS, M_PIXEL, M_NULL);
      MmeasGetResult(MeasMarker1, M_STRIPE_WIDTH, &PixelDistance1, M_NULL);
      MmeasGetResult(MeasMarker2, M_STRIPE_WIDTH, &PixelDistance2, M_NULL);

      /* Get the edges position in pixel to draw the annotations. */
      MmeasGetResult(MeasMarker1, M_POSITION+M_EDGE_FIRST,  &PosX1, &PosY1);
      MmeasGetResult(MeasMarker1, M_POSITION+M_EDGE_SECOND, &PosX2, &PosY2);
      MmeasGetResult(MeasMarker2, M_POSITION+M_EDGE_FIRST,  &PosX3, &PosY3);
      MmeasGetResult(MeasMarker2, M_POSITION+M_EDGE_SECOND, &PosX4, &PosY4);

      /* Draw the measurement indicators on the image.  */
      MgraColor(M_DEFAULT, M_COLOR_YELLOW);
      MmeasDraw(M_DEFAULT, MeasMarker1, MilOverlayImage, M_DRAW_WIDTH, M_DEFAULT, M_RESULT);
      MmeasDraw(M_DEFAULT, MeasMarker2, MilOverlayImage, M_DRAW_WIDTH, M_DEFAULT, M_RESULT);

      MgraBackColor(M_DEFAULT, M_COLOR_BLACK);
      MgraText(M_DEFAULT, MilOverlayImage, (MIL_INT)(PosX1+0.5-40),
         (MIL_INT)((PosY1+0.5)+((PosY2 - PosY1)/2.0)), MIL_TEXT(" Distance 1 "));
      MgraText(M_DEFAULT, MilOverlayImage, (MIL_INT)(PosX3+0.5-40),
         (MIL_INT)((PosY3+0.5)+((PosY4 - PosY3)/2.0)), MIL_TEXT(" Distance 2 "));

      /* Pause to show the original image and the measurement results. */
      MosPrintf(MIL_TEXT("A distorted image grabbed with the same camera was loaded and\n"));
      MosPrintf(MIL_TEXT("calibrated measurements were done to evaluate ")
                                       MIL_TEXT("the board dimensions.\n"));
      MosPrintf(MIL_TEXT("\n========================================================\n"));
      MosPrintf(MIL_TEXT("                      Distance 1          Distance 2 \n"));
      MosPrintf(MIL_TEXT("--------------------------------------------------------\n"));
      MosPrintf(MIL_TEXT(" Calibrated unit:   %8.2lf cm           %6.2lf cm    \n"),
                                                         WorldDistance1, WorldDistance2);
      MosPrintf(MIL_TEXT(" Uncalibrated unit: %8.2lf pixels       %6.2lf pixels\n"),
                                                         PixelDistance1, PixelDistance2);
      MosPrintf(MIL_TEXT("========================================================\n\n"));
      MosPrintf(MIL_TEXT("Press <Enter> to continue.\n\n"));
      MosGetch();

      /* Clear the display overlay. */
      MdispControl(MilDisplay, M_OVERLAY_CLEAR, M_DEFAULT);

      /* Read the image of the PCB. */
      MbufLoad(BOARD_IMAGE_FILE, MilImage);

      /* Transform the image of the board. */
      McalTransformImage(MilImage, MilImage, MilCalibration,
         M_BILINEAR+M_OVERSCAN_CLEAR, M_DEFAULT, M_DEFAULT);

      /* show the transformed image of the board. */
      MosPrintf(MIL_TEXT("The image was corrected to remove its distortions.\n"));

      /* Free measurement markers. */
      MmeasFree(MeasMarker1);
      MmeasFree(MeasMarker2);
      }
   else
      {
      MosPrintf(MIL_TEXT("Calibration generated an exception.\n"));
      MosPrintf(MIL_TEXT("See User Guide to resolve the situation.\n\n"));
      }

   /* Wait for a key to be pressed. */ 
   MosPrintf(MIL_TEXT("Press <Enter> to continue.\n\n"));
   MosGetch();

   /* Free all allocations. */
   McalFree(MilCalibration);
   MbufFree(MilImage);
   }


/*****************************************************************************
Tsai example. 
*****************************************************************************/
/* Source image files specification. */
#define GRID_ORIGINAL_IMAGE_FILE     M_IMAGE_PATH MIL_TEXT("CalGridOriginal.mim")
#define OBJECT_ORIGINAL_IMAGE_FILE   M_IMAGE_PATH MIL_TEXT("CalObjOriginal.mim")
#define OBJECT_MOVED_IMAGE_FILE      M_IMAGE_PATH MIL_TEXT("CalObjMoved.mim")

/* World description of the calibration grid. */
#define GRID_ORG_ROW_SPACING       1.5
#define GRID_ORG_COLUMN_SPACING    1.5
#define GRID_ORG_ROW_NUMBER        12
#define GRID_ORG_COLUMN_NUMBER     13
#define GRID_ORG_OFFSET_X          0
#define GRID_ORG_OFFSET_Y          0 
#define GRID_ORG_OFFSET_Z          0

/* Camera transformation */
#define ENCODER_TRANSLATION_X       0.817
#define ENCODER_TRANSLATION_Y       13.293
#define ENCODER_TRANSLATION_Z      -14.060
#define ENCODER_ROTATION_Y          354.207
#define ENCODER_ROTATION_X          317.467
#define ENCODER_ROTATION_Z          281.969

/* Region parameters for metrology */
#define MEASURED_CIRCLE_LABEL       1
#define RING1_POS1_X                2.3
#define RING1_POS1_Y                3.9
#define RING2_POS1_X                10.7
#define RING2_POS1_Y                11.1

#define RING1_POS2_X                8.6
#define RING1_POS2_Y                2.5
#define RING2_POS2_X                7.9
#define RING2_POS2_Y                13.2

#define RING_START_RADIUS          1.25
#define RING_END_RADIUS            2.3

/* measured plane position */
#define RING_THICKNESS             0.175
#define STEP_THICKNESS             4.0

/* Color definitions */
#define REGION_COLOR     M_RGB888(0,100,255)
#define FEATURE_COLOR    M_RGB888(255,0,255)

/* Functions declarations for this example. */
void MeasureRing(MIL_ID MilSystem, MIL_ID MilDisplay, MIL_ID MilImage, 
                 MIL_DOUBLE MeasureRing1X, MIL_DOUBLE MeasureRing1Y );
void ShowCameraInformation(MIL_ID MilCalibration);
void SetCalibrationOffset(MIL_ID MilCalibration, MIL_DOUBLE ZOffset, MIL_ID MilImage);

void TsaiCalibration(MIL_ID MilSystem, MIL_ID MilDisplay)
   {
   MIL_ID  MilImage,          /* Image buffer identifier.       */
           MilCalibration;    /* Calibration identifier.        */

   MIL_INT CalibrationStatus;          

   /* Restore source image into an automatically allocated image buffer. */
   MbufRestore(GRID_ORIGINAL_IMAGE_FILE, MilSystem, &MilImage);

   /* Display the image buffer. */
   MdispSelect(MilDisplay, MilImage);

   /* Pause to show the original image. */
   MosPrintf(MIL_TEXT("TSAI BASED CALIBRATION:\n"));
   MosPrintf(MIL_TEXT("------------\n\n"));
   MosPrintf(MIL_TEXT("The displayed grid has been grabbed with a high perspective\n"));
   MosPrintf(MIL_TEXT("camera and will be used to calibrate the camera.\n"));
   MosPrintf(MIL_TEXT("Press <Enter> to continue.\n\n"));
   MosGetch();

   /* Allocate a camera calibration context. */
   McalAlloc(MilSystem, M_TSAI_BASED, M_DEFAULT, &MilCalibration);

   /* Calibrate the camera with the image of the grid and its world description. */
   McalGrid(MilCalibration, MilImage,
            GRID_ORG_OFFSET_X, GRID_ORG_OFFSET_Y, GRID_ORG_OFFSET_Z,
            GRID_ORG_ROW_NUMBER, GRID_ORG_COLUMN_NUMBER,
            GRID_ORG_ROW_SPACING, GRID_ORG_COLUMN_SPACING,
            M_DEFAULT, M_DEFAULT);

   /* Verify if the camera calibration is successful. */
   McalInquire(MilCalibration, M_CALIBRATION_STATUS + M_TYPE_MIL_INT, &CalibrationStatus);
   if( CalibrationStatus == M_CALIBRATED )
      {
      /* Print camera information */
      MosPrintf(MIL_TEXT("The camera has been calibrated.\n\n"));
      ShowCameraInformation(MilCalibration);

      /* Load source image into an image buffer. */
      MbufLoad(OBJECT_ORIGINAL_IMAGE_FILE, MilImage);
      
      /* Set offset to the camera calibration plane and associate calibration to image. */
      /* This moves the relative origin to the top of the first measured circle */
      SetCalibrationOffset(MilCalibration, -RING_THICKNESS, MilImage);

      /* Measure the first circle. */
      MosPrintf(MIL_TEXT("First measured circle at  z = %.2f cm. "), -RING_THICKNESS);
      MeasureRing(MilSystem, MilDisplay, MilImage, RING1_POS1_X, RING1_POS1_Y );

      /* Set offset to the camera calibration plane and associate calibration to image. */
      /* This moves the relative origin to the top of the second measured circle  */
      SetCalibrationOffset(MilCalibration, -(STEP_THICKNESS+RING_THICKNESS), MilImage);

      /* Measure the second circle. */
      MosPrintf(MIL_TEXT("Second measured circle at z = %.2f cm. "), 
                                              -(STEP_THICKNESS+RING_THICKNESS));
      MeasureRing(MilSystem, MilDisplay, MilImage, RING2_POS1_X, RING2_POS1_Y );
      MosPrintf(MIL_TEXT("Press <Enter> to continue.\n\n"));
      MosGetch();

      /* Clear the overlay to transparent. */
      MdispControl(MilDisplay, M_OVERLAY_CLEAR, M_DEFAULT);

      /* Move camera rotation with the tool */
      McalSetCoordinateSystem(MilCalibration, 
                              M_TOOL_COORDINATE_SYSTEM,
                              M_ABSOLUTE_COORDINATE_SYSTEM,
                              M_ROTATION_YXZ + M_ASSIGN,
                              M_NULL,
                              ENCODER_ROTATION_Y, 
                              ENCODER_ROTATION_X, 
                              ENCODER_ROTATION_Z,
                              M_DEFAULT);

      /* Move camera position with the tool */
      McalSetCoordinateSystem(MilCalibration, 
                              M_TOOL_COORDINATE_SYSTEM,
                              M_ABSOLUTE_COORDINATE_SYSTEM,
                              M_TRANSLATION + M_COMPOSE_WITH_CURRENT,
                              M_NULL,
                              ENCODER_TRANSLATION_X, 
                              ENCODER_TRANSLATION_Y, 
                              ENCODER_TRANSLATION_Z,
                              M_DEFAULT);

      /* Load source image into an image buffer. */
      MbufLoad(OBJECT_MOVED_IMAGE_FILE, MilImage);

      /* Print camera information */
      MosPrintf(MIL_TEXT("Calibration module moved camera position and camera \n"));
      MosPrintf(MIL_TEXT("orientation according to known encoder transformation.\n\n"));      
      ShowCameraInformation(MilCalibration);

      /* Set offset to the camera calibration plane and associate calibration to image. */
      /* This moves the relative origin to the top of the first measured circle   */
      SetCalibrationOffset(MilCalibration, -RING_THICKNESS, MilImage);

      /* Measure the first circle. */
      MosPrintf(MIL_TEXT("First measured circle at  z = %.2f cm. "), -RING_THICKNESS);
      MeasureRing(MilSystem, MilDisplay, MilImage, RING1_POS2_X, RING1_POS2_Y );

      /* Set offset to the camera calibration plane and associate calibration to image. */
      /* This moves the relative origin to the top of the second measured circle  */
      SetCalibrationOffset(MilCalibration, -(STEP_THICKNESS+RING_THICKNESS), MilImage);

      /* Measure the second circle. */
      MosPrintf(MIL_TEXT("Second measured circle at z = %.2f cm. "), 
                                              -(STEP_THICKNESS+RING_THICKNESS));
      MeasureRing(MilSystem, MilDisplay, MilImage, RING2_POS2_X, RING2_POS2_Y );
      
      MosPrintf(MIL_TEXT("Press <Enter> to quit.\n\n"));
      MosGetch();
      }
   else
      {
      MosPrintf(MIL_TEXT("Calibration generated an exception.\n"));
      MosPrintf(MIL_TEXT("See User Guide to resolve the situation.\n\n"));
      }

   /* Free all allocations. */
   McalFree(MilCalibration);
   MbufFree(MilImage);
   }

/* Offset camera calibration plane. */
void SetCalibrationOffset(MIL_ID MilCalibration, MIL_DOUBLE ZOffset, MIL_ID MilImage)
   {
   McalSetCoordinateSystem(MilCalibration, 
                           M_RELATIVE_COORDINATE_SYSTEM,
                           M_ABSOLUTE_COORDINATE_SYSTEM,
                           M_TRANSLATION + M_ASSIGN,
                           M_NULL,
                           0, 0, ZOffset,
                           M_DEFAULT);

   /* Associate calibration context to source image */   
   McalAssociate(MilCalibration, MilImage, M_DEFAULT);
   }

/* Measuring function with MilMetrology module */
void MeasureRing(MIL_ID MilSystem, MIL_ID MilDisplay, MIL_ID MilImage, 
                    MIL_DOUBLE MeasureRingX, MIL_DOUBLE MeasureRingY )
   {
   MIL_ID  MilMetrolContext,  /* Metrology Context              */
           MilMetrolResult,   /* Metrology Result               */
           MilOverlayImage;   /* Overlay image.                 */

   MIL_DOUBLE Value;

   /* Prepare for overlay annotation. */
   MdispControl(MilDisplay, M_OVERLAY, M_ENABLE);
   MdispInquire(MilDisplay, M_OVERLAY_ID, &MilOverlayImage);

   /* Allocate metrology context and result. */
   MmetAlloc(MilSystem, M_DEFAULT, &MilMetrolContext);
   MmetAllocResult(MilSystem, M_DEFAULT, &MilMetrolResult);

   /* Add a first measured segment feature to context and set its search region */
   MmetAddFeature(MilMetrolContext, M_MEASURED, M_CIRCLE, MEASURED_CIRCLE_LABEL,
                  M_DEFAULT, M_NULL, M_NULL, 0, M_DEFAULT);

   MmetSetRegion(MilMetrolContext, M_FEATURE_LABEL(MEASURED_CIRCLE_LABEL), 
                 M_DEFAULT, M_RING,
                 MeasureRingX, MeasureRingY,
                 RING_START_RADIUS, RING_END_RADIUS,
                 M_NULL, M_NULL );

   /* Calculate */
   MmetCalculate(MilMetrolContext, MilImage, MilMetrolResult, M_DEFAULT);

   /* Draw region */
   MgraColor(M_DEFAULT, REGION_COLOR);
   MmetDraw(M_DEFAULT, MilMetrolResult, MilOverlayImage, M_DRAW_REGION, M_DEFAULT, M_DEFAULT);

   /* Draw features */
   MgraColor(M_DEFAULT, FEATURE_COLOR);
   MmetDraw(M_DEFAULT, MilMetrolResult, MilOverlayImage, M_DRAW_FEATURE, M_DEFAULT, M_DEFAULT);

   MmetGetResult(MilMetrolResult, M_FEATURE_LABEL(MEASURED_CIRCLE_LABEL), M_RADIUS, &Value);
   MosPrintf(MIL_TEXT("Measured Radius: %.3f cm\n"), Value );

   /* Free all allocations. */
   MmetFree(MilMetrolResult);
   MmetFree(MilMetrolContext);
   }

/* Print the current camera position and orientation  */
void ShowCameraInformation(MIL_ID MilCalibration)
   {
   MIL_DOUBLE CameraPosX,
              CameraPosY,
              CameraPosZ,
              CameraYaw,
              CameraPitch,
              CameraRoll;

   McalGetCoordinateSystem(MilCalibration,
                           M_CAMERA_COORDINATE_SYSTEM,
                           M_ABSOLUTE_COORDINATE_SYSTEM,
                           M_TRANSLATION,
                           M_NULL,
                           &CameraPosX, &CameraPosY, &CameraPosZ, 
                           M_NULL);

   McalGetCoordinateSystem(MilCalibration,
                           M_CAMERA_COORDINATE_SYSTEM,
                           M_ABSOLUTE_COORDINATE_SYSTEM,
                           M_ROTATION_YXZ,
                           M_NULL,
                           &CameraYaw, &CameraPitch, &CameraRoll, 
                           M_NULL);

   /* Pause to show the corrected image of the grid. */
   MosPrintf(MIL_TEXT("Camera Position in cm:          (x, y, z)           ")
             MIL_TEXT("(%.2f, %.2f, %.2f)\n"), CameraPosX, CameraPosY, CameraPosZ);
   MosPrintf(MIL_TEXT("Camera Orientation in degrees:  (yaw, pitch, roll)  ")
             MIL_TEXT("(%.2f, %.2f, %.2f)\n"), CameraYaw, CameraPitch, CameraRoll);
   MosPrintf(MIL_TEXT("Press <Enter> to continue.\n\n"));
   MosGetch();
   }