void Ball::update(Uint32 deltaTime, AngularWall * wallAngle)
{
BasePhysics::update(deltaTime);
updateLabels(deltaTime);
//Detect the collision with the ground
if ((Ypos - ballRadius) < pixelsToMeters(10))
{
Ypos = pixelsToMeters(10.01) + ballRadius;
Yvel = R *- Yvel;
Xvel *= R;
}
//Collision detection with the right wall
if ((Xpos + ballRadius) > pixelsToMeters(1490))
{
Xpos = pixelsToMeters(1489.99) - ballRadius;
Yvel *= R;
Xvel = R *- Xvel;
}
//Collision detection with the left wall
if ((Xpos - ballRadius) < pixelsToMeters(10))
{
Xpos = pixelsToMeters(10.01) + ballRadius;
Yvel *= R;
Xvel = R *-Xvel;
}
//Collision detection against angular wall
Vector2D pos(Xpos, Ypos);
//For each side of the wall
for (int i = 0; i < 4; i++)
{
//Get the start and end points of the line that represents this edge
Vector2D start, end;
wallAngle->getWallPoints(i, start, end);
//Project the ball onto this line
Vector2D point = GetClosestPointOnLineSegment(start, end, pos);
float dist = (point - pos).length();
// If the closest point on the line segment is within the bounds of our radius, then we have collided with it
if (dist <= ballRadius)
{
Vector2D surfaceNormal = wallAngle->getSurfaceNormal(i);
//Push the ball out so it isn't colliding anymore
Vector2D newpos = point + (surfaceNormal * (ballRadius + pixelsToMeters(0.01)));
Xpos = newpos.x;
Ypos = newpos.y;
//Since we have collided wih the wall, we need to bounce off it
//To do so, we reflect the ball's velocity, around the wall's edge's surfacenormal
//This code was adapted from: http://www.3dkingdoms.com/weekly/weekly.php?a=2
Vector2D incoming(Xvel, Yvel);
Vector2D result = surfaceNormal * incoming.dot(surfaceNormal);
result *= -2.f;
result += incoming;
result *= R;
Xvel = result.x;
Yvel = result.y;
}
}
}
bool LineInsideCircle(const LineSegment& aLine, const CommonUtilities::Vector::Vector2<float>& aCircleCenterPosition, const float aCircleRadius)
{
CommonUtilities::Vector::Vector2<float> closestPoint = GetClosestPointOnLineSegment(aLine, aCircleCenterPosition);
return PointInsideCircle(closestPoint, aCircleCenterPosition, aCircleRadius);
}
