static void collideWith(MobileSpaceObject* object) {
// check for collision with each mobile object
for (typename std::list<Derived*>::iterator it = Derived::activeParticles_.begin(); it != Derived::activeParticles_.end(); ++it) {
// don't check for self collision
if (*it != object) {
// get faster object
MobileSpaceObject *source, *target;
if (object->velocity() > (*it)->velocity()) {
source = object;
target = *it;
}
else {
source = *it;
target = object;
}
const float minDistSquared = std::pow(object->radius() + (*it)->radius(), 2);
// if objects are moving
if (source->velocity().lengthSquare() > 0) {
const Vector2f velocitySourceNorm ( source->velocity().normalize());
const Vector2f velocitySourceOrtho (-velocitySourceNorm.y_, velocitySourceNorm.x_);
const Vector2f centerDist ( velocitySourceOrtho * ((source->location() - target->location())*velocitySourceOrtho));
// if path of object crosses target object
if (centerDist.lengthSquare() < minDistSquared) {
const Vector2f lastFrameLocation = source->location() - source->velocity()*timer::frameTime()*0.6f;
const Vector2f chordMidPoint = target->location() + centerDist;
// if path of object has intersected with target within the last frame
if ( ((source->location() - target->location() ).lengthSquare() < minDistSquared)
|| ((lastFrameLocation - target->location() ).lengthSquare() < minDistSquared)
|| ((chordMidPoint - source->location())*(chordMidPoint - lastFrameLocation) < 0.f)) {
if (source->velocity()*(target->location() - lastFrameLocation) > 0) {
const Vector2f impactLocation ((source->location() + target->location())*0.5f);
const Vector2f impactDirection ((target->location() - source->location()).normalize());
// calculate velocity of objects in direction of impact before collision
const Vector2f velocitySourceBefore = impactDirection * (source->velocity() * impactDirection);
const Vector2f velocityTargetBefore = impactDirection * (target->velocity() * impactDirection);
// calculate velocity of objects in direction of impact after collision
const Vector2f velocitySourceAfter = (velocitySourceBefore*source->mass() + velocityTargetBefore*target->mass() - (velocitySourceBefore - velocityTargetBefore)*target->mass()) / (source->mass() + target->mass());
const Vector2f velocityTargetAfter = (velocitySourceBefore*source->mass() + velocityTargetBefore*target->mass() - (velocityTargetBefore - velocitySourceBefore)*source->mass()) / (source->mass() + target->mass());
// calculate collision result
target->onCollision(source, impactLocation, impactDirection, velocitySourceBefore);
source->onCollision(target, impactLocation, impactDirection, velocityTargetBefore);
// add to orthongonal speed component of initial velocity
// special case: Collision with rofle bullets is not physically correct, for improved gameplay
if ((source->type() == spaceObjects::oAmmoROFLE) | (target->type() == spaceObjects::oAmmoROFLE))
target-> velocity() += (0.05f*source->velocity()*source->mass() + (velocityTargetAfter - velocityTargetBefore) * 0.6);
else if (((source->type() == spaceObjects::oAmmoRocket) | (target->type() == spaceObjects::oAmmoRocket)) &&
((source->type() != spaceObjects::oAmmoFist) | (target->type() != spaceObjects::oAmmoFist))) {
source->velocity() += (velocitySourceAfter - velocitySourceBefore) * 0.8;
target->velocity() += (velocityTargetAfter - velocityTargetBefore) * 0.1;
}
else {
source->velocity() += (velocitySourceAfter - velocitySourceBefore) * 0.8;
target->velocity() += (velocityTargetAfter - velocityTargetBefore) * 0.8;
}
}
}
}
}
}
}
}
