Polygon::Polygon(std::vector<Vec2> v)
{
mType = PolygonType;
for (std::vector<Vec2>::iterator iter = v.begin(); iter != v.end(); iter++) {
vertices.push_back(*iter);
}
axes.reserve(vertices.size());
for (unsigned i = 0; i < getVertsNum(); i++) {
// get the current vertex
Vec2 p1 = vertices[i];
// get the next vertex
Vec2 p2 = vertices[i + 1 == getVertsNum() ? 0 : i + 1];
// subtract thw two to get the edge vector
Vec2 edge = Subtract(p1, p2);
// get either perpendicular vector
Vec2 normal = edge.Perpendicular();
Normalize(normal);
axes.emplace_back(normal);
}
}
void PolygonCollider::Init(std::vector<Vec2>& vec)
{
mType = PolygonType;
FirstPoint(vec);
PointAngle(vec);
PointSort(vec, vertices);
PointSearch(vec, vertices);
Vec2 normal{};
Vec2 u = vertices[1] - vertices[0];
Vec2 v = vertices[2] - vertices[0];
normal = Cross(u, v);
Normalize(normal);
for (unsigned i = 0; i < vertices.size(); i++)
{
vertices[i].nx = normal.x;
vertices[i].ny = normal.y;
vertices[i].nz = normal.z;
}
COPY_TO_VERTEXBUFFER();
axes.reserve(getVertsNum());
for (unsigned i = 0; i < getVertsNum(); i++) {
// get the current vertex
Vec2 p1 = vertices[i];
// get the next vertex
Vec2 p2 = vertices[i + 1 == getVertsNum() ? 0 : i + 1];
// subtract thw two to get the edge vector
Vec2 edge = Subtract(p1, p2);
// get either perpendicular vector
Vec2 normal = edge.Perpendicular();
Normalize(normal);
axes.emplace_back(normal);
}
}
Direction GetRotationDirection(Vec2 heading, Vec2 target) {
Vec2 perp = heading.Perpendicular();
target.Normalize();
return perp.Dot(target) >= 0.0 ? Direction::Right : Direction::Left;
}