// Create array for use of ConvertCoordinates method.
ImGearPoint[] igPoints = new ImGearPoint[1];
// Setup location for the point based on display coordinates,
// often received from mouse events.
igPoints[0] = new ImGearPoint(100, 100);
// Convert point from display coordinates to image coordinates.
igARTPage.ConvertCoordinates(
igPageView, igPageView.Display, igPageView.CreateGraphics(),
ImGearCoordConvModes.DEVICE_TO_IMAGE, igPoints
);
// Setup color for the point.
ImGearRGBQuad igRGBQuad = new ImGearRGBQuad(0, 255, 0);
// Create the point annotation with a width of 10 and 60% opacity
ImGearARTPoint igARTPoint = new ImGearARTPoint(
igPoints[0], igRGBQuad, 10, (int)(0.60 * 255)
);
// Add the annotation to the ARTPage.
igARTPage.AddMark(igARTPoint, ImGearARTCoordinatesType.IMAGE_COORD);