MTV PolygonvsPolygon(Shape* pa, Shape* pb)
{
Polygon* a = dynamic_cast<Polygon*>(pa);
Polygon* b = dynamic_cast<Polygon*>(pb);
Vec2 smallest;
float overlap = FLT_MAX;
for (unsigned i = 0; i < a->getAxesNum(); i++) {
Vec2 axis = a->getAxes(i);
Projection p1 = a->project(axis);
Projection p2 = b->project(axis);
if (!p1.overlap(p2)) {
return MTV(false);
}
else {
// get the overlap
float o = p1.getOverlap(p2);
o = fabs(o);
// check for minimum
if (o < overlap) {
// then set this one as smallest
overlap = o;
smallest = axis;
Vec2 d;
d = a->Center() - b->Center();
if (Dot(d, smallest) < 0)
smallest.Negate();
}
}
}
for (unsigned i = 0; i < b->getAxesNum(); i++) {
Vec2 axis = b->getAxes(i);
Projection p1 = a->project(axis);
Projection p2 = b->project(axis);
if (!p1.overlap(p2)) {
return MTV(false);
}
else {
// get the overlap
float o = p1.getOverlap(p2);
o = fabs(o);
// check for minimum
if (o < overlap) {
// then set this one as smallest
overlap = o;
smallest = axis;
Vec2 d;
d = a->Center() - b->Center();
if (Dot(d, smallest) < 0)
smallest.Negate();
}
}
}
return MTV(smallest, overlap, true);
}
MTV CirclevsPolygon(Shape* pa, Shape* pb)
{
Circle* a = dynamic_cast<Circle*>(pa);
Polygon* b = dynamic_cast<Polygon*>(pb);
// Transform circle center to Polygon model space
Vec2 center = a->center;
// Find edge with minimum penetration
float separation = -FLT_MAX;
unsigned faceNormal = 0;
for (unsigned i = 0; i < b->getVertsNum(); ++i)
{
float s = Dot(b->getAxes(i), center - b->vertices[i]);
if (s > a->radius) {
return MTV(false);
}
if (s > separation) {
separation = s;
faceNormal = i;
}
}
// Grab face's vertices
Vec2 v1 = b->vertices[faceNormal];
unsigned i2 = faceNormal + 1 < b->getVertsNum() ? faceNormal + 1 : 0;
Vec2 v2 = b->vertices[i2];
// Determine which voronoi region of the edge center of circle lies within
float dot1 = Dot(center - v1, v2 - v1);
float dot2 = Dot(center - v2, v1 - v2);
if (dot1 <= 0.0f) {
if (DistSqr(center, v1) > a->radius * a->radius)
return MTV(false);
}
else if (dot2 <= 0.0f) {
if (DistSqr(center, v2) > a->radius * a->radius)
return MTV(false);
}
else {
Vec2 n = b->getAxes(faceNormal);
if (Dot(center - v1, n) > a->radius)
return MTV(false);
}
return MTV(b->getAxes(faceNormal), a->radius - separation, true);
}
MTV CirclevsCircle(Shape* pa, Shape* pb)
{
Circle* a = dynamic_cast<Circle*>(pa);
Circle* b = dynamic_cast<Circle*>(pb);
float r = a->radius + b->radius;
float p = Magnitude((a->center) - (b->center)) - r;
if (p < 0) {
Vec2 normal = a->center - b->center;
Normalize(normal);
p = abs(p);
return MTV(normal,p,true);
}
return MTV(false);
}
#include "Collision.h"
#include "Projection.h"
MTV MTV::NONE = MTV(0,maths::Vector2(0,0));
Collision::~Collision(){
}
float Collision::minValue(float a,float b,float c,float d){
float min = a;
min = (b < min ? b : min);
min = (c < min ? c : min);
min = (d < min ? d : min);
return min;
}
float Collision::maxValue(float a,float b,float c,float d){
float max = a;
max = (b > max ? b : max);
max = (c > max ? c : max);
max = (c > max ? c : max);
return max;
}
MTV Collision::getCollision(const sf::Sprite& object1,Entity::ENTITY_SHAPE shape1,const sf::Sprite& object2,Entity::ENTITY_SHAPE shape2){
//Use Separating Axis Theorem to determine whether two objects are overlapping
//See documentation for full explanation of this algorithm
//Get the oriented bounding box in world coordinates (includes rotation) of objects
OBB obb1 = getOBB(object1);