public static float projection(VectorF a, VectorF b)
{
if (b.isZero())
{
return(0.0f);
}
return((a.x * b.x + a.y * b.y) / b.length());
}
public void RunCollision(VectorF impactVelocity, float deltaTime)
{
if (this.numHits == 0)
{
return;
}
VectorF posImpact = VectorF.zero();
VectorF negImpact = VectorF.zero();
int i = 0;
for (i = 0; i < NUM_COLLISION_POINTS; i += 1)
{
if (this.collPtHit[i] < 0)
{
continue;
}
if (this.oldCollPtHit[i] == this.collPtHit[i])
{
continue;
}
VectorF impact = VectorF.subtract(this.collPoint[i], this.oldCollPt[i]);
if (impact.isZero())
{
continue;
}
impact.normalize();
float velProjection = VectorF.projection(this.velocity, impact);
if (velProjection > 0.0f)
{
impact.scale(-velProjection * (2.0f - this.hardImpactLossFactor));
posImpact.max(impact);
negImpact.min(impact);
}
}
impactVelocity.add(posImpact);
impactVelocity.add(negImpact);
}
public VectorF DetectCollision(VectorF[] rect, VectorF otherVelocity, int otherIndex)
{
this.numCarHits = 0;
VectorF p21 = VectorF.subtract(rect[1], rect[0]);
VectorF p41 = VectorF.subtract(rect[3], rect[0]);
float p21magnitude_squared = p21.x * p21.x + p21.y * p21.y;
float p41magnitude_squared = p41.x * p41.x + p41.y * p41.y;
int i = 0;
for (i = 0; i < NUM_COLLISION_POINTS; i += 1)
{
this.collPtCarHit[i] = -1;
VectorF p = VectorF.subtract(this.collPoint[i], rect[0]);
float pp21 = p.x * p21.x + p.y * p21.y;
if (pp21 >= 0.0 && pp21 <= p21magnitude_squared)
{
float pp41 = p.x * p41.x + p.y * p41.y;
if (pp41 >= 0.0 && pp41 <= p41magnitude_squared)
{
this.collPtCarHit[i] = otherIndex;
this.numCarHits += 1;
}
}
}
if (this.numCarHits == 0)
{
return(null);
}
VectorF impactVelocity = new VectorF();
VectorF posImpact = VectorF.zero();
VectorF negImpact = VectorF.zero();
for (i = 0; i < NUM_COLLISION_POINTS; i += 1)
{
if (this.collPtCarHit[i] < 0)
{
continue;
}
if (this.oldCollPtCarHit[i] == this.collPtCarHit[i])
{
continue;
}
VectorF impact = VectorF.subtract(this.collPoint[i], this.oldCollPt[i]);
if (impact.isZero())
{
continue;
}
impact.normalize();
float velProjection = VectorF.projection(this.velocity, impact);
if (velProjection > 0.0f)
{
impact.scale(-velProjection * (1.0f - this.softImpactLossFactor));
posImpact.max(impact);
negImpact.min(impact);
impact.negate();
impact.normalize();
}
float otherProjection = VectorF.projection(otherVelocity, impact);
if (otherProjection < 0.0f)
{
impact.scale(otherProjection * (1.0f - this.softImpactLossFactor));
posImpact.max(impact);
negImpact.min(impact);
}
}
impactVelocity.add(posImpact);
impactVelocity.add(negImpact);
return(impactVelocity);
}
