public static bool PassSector(Car objA, Background background, Color markerColor)
{
// Calculate a matrix which transforms from A's local space into
// world space and then into B's local space
Matrix transformAToB = objA.transformMatrix * Matrix.Invert(background.transformMatrix);
//For each row of pixel in A
for (int yA = 0; yA < objA.Height; yA++)
{
//For each pixel in that row
for (int xA = 0; xA < objA.Width; xA++)
{
//Calculate this pixel's location in B
Vector2 positionInB = Vector2.Transform(new Vector2(xA, yA), transformAToB);
int xB = (int)Math.Round(positionInB.X);
int yB = (int)Math.Round(positionInB.Y);
if (xB >= 0 && xB < background.Width &&
yB >= 0 && yB < background.Height)
{
//Get colors of the overlapping pixels
Color colorA = objA.colorData[xA + yA * objA.Width];
Color colorB = background.colorData[xB + yB * background.Width];
//If both pixels are not completely transparent
if (colorA.A != 0 && colorB == markerColor)
{
//Intersection found
return true;
}
}
}
}
//No intersection
return false;
}
public override void Update(GameTime gameTime)
{
KeyboardState newState = Keyboard.GetState();
if (lastCountdown == new TimeSpan())
lastCountdown = gameTime.TotalGameTime;
if (countdown > 0 && lastCountdown + countdownTime < gameTime.TotalGameTime)
{
countdown -= 1;
lastCountdown = gameTime.TotalGameTime;
}
if (countdown <= 1)
{
if (!gameDone)
{
//Update Cars
if (Car.OnGrass(carBasic, background))
{
carBasic.speedMax = 4.5f;
carBasic.accel = 0.05f;
carBasic.friction = 0.2f;
}
else
{
carBasic.speedMax = 6;
carBasic.accel = 0.1f;
carBasic.friction = 0.1f;
}
carBasic.Update();
Car.AICarSteer(aiCar, background);
aiCar.Update();
}
else
{
if (oldState.IsKeyUp(Keys.Enter) && newState.IsKeyDown(Keys.Enter))
{
ScreenEvent.Invoke(this, new EventArgs());
}
}
}
//Check and change car sectors
if (carBasic.sector == 2 && Car.PassSector(carBasic, background, sector1Color))
{
carBasic.sector = 1;
carBasic.lap += 1;
}
else if (carBasic.sector == 1 && Car.PassSector(carBasic, background, sector2Color))
{
carBasic.sector = 2;
}
if (aiCar.sector == 2 && Car.PassSector(aiCar, background, sector1Color))
{
aiCar.sector = 1;
aiCar.lap += 1;
}
else if (aiCar.sector == 1 && Car.PassSector(aiCar, background, sector2Color))
{
aiCar.sector = 2;
}
if (carBasic.lap >= 10)
{
gameDone = true;
winner = carBasic;
}
else if (aiCar.lap >= 10)
{
gameDone = true;
winner = aiCar;
}
oldState = newState;
base.Update(gameTime);
}