//
// Check if the trailer is colliding with the drag vehicle
//
public static bool IsTrailerCollidingWithDragVehicle(
Vector3 semiRearWheelPos, float semiHeading, CarData semiData,
Vector3 trailerRearWheelPos, float trailerHeading, CarData trailerData)
{
bool isColliding = false;
//Use triangle-traingle intersection so we need the rectangles
Vector3 trailerCenter = trailerData.GetCenterPos(trailerRearWheelPos, trailerHeading);
Rectangle trailerRect = CarData.GetCornerPositions(trailerCenter, trailerHeading, trailerData.carWidth * 0.9f, trailerData.CarLength);
//The semi's cabin rectangle
Vector3 cabinCenter = semiData.GetSemiCabinCenter(semiRearWheelPos, semiHeading);
//Make it slightly shorter or too many false collisions
Rectangle semiRect = CarData.GetCornerPositions(cabinCenter, semiHeading, semiData.carWidth, semiData.cabinLength * 0.95f);
if (Intersections.AreRectangleRectangleIntersecting(trailerRect, semiRect))
{
return(true);
}
return(isColliding);
}
//
// Check if the car is colliding with an obstacle or is outside of map
//
public static bool HasCarInvalidPosition(Vector3 carRearWheelPos, float heading, CarData carData, Map map)
{
bool hasInvalidPosition = false;
//Step 1. Check if the car's rear wheel center is inside of the map
IntVector2 rearWheelCellPos = map.ConvertWorldToCell(carRearWheelPos);
if (!map.IsCellWithinGrid(rearWheelCellPos))
{
//This is not a valid position
hasInvalidPosition = true;
return(hasInvalidPosition);
}
//Step 2. Check if any of the car's corner is outside of the map
//Make the car bigger than it is to be on the safe side
float carLength = carData.CarLength + Parameters.marginOfSafety;
float carWidth = carData.carWidth + Parameters.marginOfSafety;
Vector3 carCenterPos = carData.GetCenterPos(carRearWheelPos, heading);
//Find all corners of the car
Rectangle corners = CarData.GetCornerPositions(carCenterPos, heading, carWidth, carLength);
//Detect if any of the corners is outside of the map = is the cell the corner is a part of the map
HashSet <IntVector2> carCellPositions = new HashSet <IntVector2>();
carCellPositions.Add(map.ConvertWorldToCell(corners.FL));
carCellPositions.Add(map.ConvertWorldToCell(corners.FR));
carCellPositions.Add(map.ConvertWorldToCell(corners.BL));
carCellPositions.Add(map.ConvertWorldToCell(corners.BR));
foreach (IntVector2 cellPos in carCellPositions)
{
if (!map.IsCellWithinGrid(cellPos))
{
//At least one of the corners is outside of the map
hasInvalidPosition = true;
return(hasInvalidPosition);
}
}
//Step 3. Check if some of the car's known positions are far away from an obstacle
//The car is not colliding with anything if the steps to an obstacle from center of car is greater than the length of the car
IntVector2 carCenterCellPos = map.ConvertWorldToCell(carCenterPos);
if (map.cellData[carCenterCellPos.x, carCenterCellPos.z].distanceToClosestObstacle > carData.CarLength * 0.7f)
{
//This is a valid position
hasInvalidPosition = false;
return(hasInvalidPosition);
}
//Step 4. Check if the car is hitting an obstacle
//Use the car's corners and then rectangle-rectangle-intersection with the obstacles
hasInvalidPosition = IsCarIntersectingWithObstacles(corners, carCenterCellPos, map);
return(hasInvalidPosition);
}