C# Display Enumeration Sample (Windows only) Complete Code

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using System;
using System.Drawing;
using System.Windows.Forms;
namespace CSharpSample
class Program
static void Main()
// create the interaction library
Tobii.InteractionLib.IInteractionLib intlib =
// EnumerateDisplayAreas will enumerate all displays on the windows machine, including their
// virtual screen bounds and display IDs, and put the results into an IList<MonitorDisplayArea>.
// The display IDs have the same formatting as are used on Tobii eyetrackers to
// identify which display they are attached to.
foreach (var area in DisplayEnumerationHelper.DisplayEnumerationHelper.EnumerateDisplayAreas())
// For each display we tell the Interaction Library
// 1) the coordinate scaling we want to use by giving the size as we see it
// 2) the size and origin in virtual screen coordinates, and
// 3) the ID of the display.
// Interaction Library will use this information to map connected devices to display areas,
// to transform all data streams when outputting them and to properly transform all added
// interactors to its internal, global coordinate space when performing gaze focus calculations.
// Here we are using the native scaling (so first to parameters are the same as the virtual
// screen size) but we could have used any scaling we like, eg (1.0, 1.0) for relative
// coordinates.
area.wVirtual, area.hVirtual,
area.wVirtual, area.hVirtual,
area.xVirtual, area.yVirtual,
var form = new Form();
form.Text = "Interactor Window";
// By telling the Interaction Library to offset the coordinate system origin
// so that it matches the location of the window client area, we can add and
// update interactors using window-local coordinates.
// The origin offset has to be in the virtual coordinate space we used when
// adding the display areas above.
form.Move += (sender, e) =>
var offset = form.PointToScreen(new Point(0, 0));
intlib.CoordinateTransformSetOriginOffset(offset.X, offset.Y);
// In this sample we want the entire window client area to be an interactor
// that changes color when it gets and loses gaze focus.
void AddOrUpdateInteractor(Size clientSize)
var rect = new Tobii.InteractionLib.Rectangle(0, 0, clientSize.Width, clientSize.Height);
intlib.AddOrUpdateInteractor(0, rect, 0);
form.Resize += (sender, e) => AddOrUpdateInteractor(form.ClientSize);
// Subscribe to gaze focus events. When the form client area (which is an
// interactor) gets or loses gaze focus, set the form color accordingly.
intlib.GazeFocusEvent += e => form.BackColor = e.hasFocus ?
SystemColors.Highlight :
var closed = false;
form.Closed += (sender, e) => closed = true;
// Now that all events and subscriptions are set up, the physical form can be created.
// Handle window events and update interaction library to trigger all callbacks
while (!closed)