public bool ClipRay(
Point2d rayOrigin,
Vector2d rayDirection,
out float clipMinT,
out float clipMaxT)
{
bool intersects = false;
Vector2d tMin = new Vector2d();
Vector2d tMax = new Vector2d();
// Compute the ray intersection times along the x-axis
if (rayDirection.i > MathConstants.EPSILON)
{
// ray has positive x component
tMin.i = (m_pMin.x - rayOrigin.x) / rayDirection.i;
tMax.i = (m_pMax.x - rayOrigin.x) / rayDirection.i;
}
else if (rayDirection.i < -MathConstants.EPSILON)
{
// ray has negative x component
tMin.i = (m_pMax.x - rayOrigin.x) / rayDirection.i;
tMax.i = (m_pMin.x - rayOrigin.x) / rayDirection.i;
}
else
{
// Ray has no x component (parallel to x-axis)
tMin.i = MathConstants.REAL_MIN;
tMax.i = MathConstants.REAL_MAX;
}
// Compute the ray intersection times along the y-axis
if (rayDirection.j > MathConstants.EPSILON)
{
// ray has positive y component
tMin.j = (m_pMin.y - rayOrigin.y) / rayDirection.j;
tMax.j = (m_pMax.y - rayOrigin.y) / rayDirection.j;
}
else if (rayDirection.j < -MathConstants.EPSILON)
{
// ray has negative y component
tMin.j = (m_pMax.y - rayOrigin.y) / rayDirection.j;
tMax.j = (m_pMin.y - rayOrigin.y) / rayDirection.j;
}
else
{
// Ray has no y component (parallel to y-axis)
tMin.j = MathConstants.REAL_MIN;
tMax.j = MathConstants.REAL_MAX;
}
// Ray only intersects AABB if minT is before maxT and maxT is non-negative
clipMinT = tMin.MaxComponent();
clipMaxT = tMax.MinComponent();
intersects = clipMinT < clipMaxT && clipMaxT >= 0;
return intersects;
}
public static eDirection GetDirectionForVector(Vector2d vector)
{
eDirection direction = eDirection.none;
if (vector.MagnitudeSquared() > EPSILON_SQUARED)
{
if (vector.i > 0)
{
if (vector.j > vector.i)
{
direction = eDirection.down;
}
else if (vector.j < -vector.i)
{
direction = eDirection.up;
}
else
{
direction = eDirection.right;
}
}
else
{
if (vector.j > -vector.i)
{
direction = eDirection.down;
}
else if (vector.j < vector.i)
{
direction = eDirection.up;
}
else
{
direction = eDirection.left;
}
}
}
return direction;
}
public static float GetAngleForVector(Vector2d v)
{
// (1, 0) -> 0 degrees
// (0, 1) -> 90 degrees
// (-1, 0) -> 180 degrees
// (0, -1) -> 270 degrees
return (((float)Math.Atan2(v.j, v.i) + MathConstants.TWO_PI) % MathConstants.TWO_PI) * RADIANS_TO_DEGREES;
}
public float Dot(Vector2d v)
{
return i * v.i + j * v.j;
}
public float Cross(Vector2d v)
{
return i * v.j - v.i * j;
}
public void Copy(Vector2d v)
{
this.i = v.i;
this.j = v.j;
}
public Vector2d(Vector2d v)
{
this.i = v.i;
this.j = v.j;
}
public float NormalizeWithDefault(Vector2d defaultVector)
{
float length = Magnitude();
if (length > MathConstants.EPSILON)
{
ScaleBy(1.0f / length);
}
else
{
Copy(defaultVector);
}
return length;
}
public Point2d Offset(Vector2d v)
{
return new Point2d(x + v.i, y + v.j);
}
public void Move(Vector2d v)
{
m_pMin += v;
m_pMax += v;
}
