/// <summary>
/// Draws the radius of size sightDistance around the agent.
///
/// Adaptation of Lague, S. (2015) Field of view visualisation (E01). Available at: https://www.youtube.com/watch?v=rQG9aUWarwE (Accessed: 05 January 2018).
/// </summary>
private void OnSceneGUI()
{
VisionCone cone = (VisionCone)target; // Agent's FOV cone in game
Handles.color = Color.white; // Change colour to white
// View distance
Handles.DrawWireArc(cone.transform.position, Vector3.up, Vector3.forward, 360, cone.viewDistance); // Draw a circle of radius sightDistance around agent
// View angle
// Get the angle in radians of half the view angle left and right of the agent's forward vector.
float rightSightAngle = ((cone.FOV / 2) + cone.transform.eulerAngles.y) * Mathf.Deg2Rad;
float leftSightAngle = ((cone.FOV / 2) - cone.transform.eulerAngles.y) * Mathf.Deg2Rad;
// Convert these angles to direction vectors
Vector3 rightSightPoint = new Vector3(Mathf.Sin(rightSightAngle), 0.0f, Mathf.Cos(rightSightAngle));
Vector3 leftSightPoint = new Vector3(Mathf.Sin(-leftSightAngle), 0.0f, Mathf.Cos(-leftSightAngle));
// Draw a line from the agent's position, along the direction vectors until they intersect with the view distance.
Handles.DrawLine(cone.transform.position, cone.transform.position + rightSightPoint * cone.viewDistance);
Handles.DrawLine(cone.transform.position, cone.transform.position + leftSightPoint * cone.viewDistance);
// Enemies in proximity
List <GameObject> enemies = cone.getNearbyTargets();
List <GameObject> visibleEnemies = cone.getNearbyTargets();
for (int i = 0; i < enemies.Count; i++)
{
if (!visibleEnemies.Contains(enemies[i])) // Can't see enemy
{
Handles.color = Color.red;
}
else
{
float percentageVisible = cone.getTimeVisible(enemies[i]) / cone.timeToSpot;
Color visibilityColour = new Color(1 - percentageVisible, percentageVisible, 0);
Handles.color = visibilityColour;
}
Handles.DrawLine(cone.transform.position, enemies[i].transform.position);
}
}