#include "config.h"
#include "FloatQuad.h"
#include <algorithm>
#include <limits>
using namespace std;
namespace WebCore {
static inline float min4(float a, float b, float c, float d)
{
return min(min(a, b), min(c, d));
}
static inline float max4(float a, float b, float c, float d)
{
return max(max(a, b), max(c, d));
}
inline float dot(const FloatSize& a, const FloatSize& b)
{
return a.width() * b.width() + a.height() * b.height();
}
inline bool isPointInTriangle(const FloatPoint& p, const FloatPoint& t1, const FloatPoint& t2, const FloatPoint& t3)
{
FloatSize v0 = t3 - t1;
FloatSize v1 = t2 - t1;
FloatSize v2 = p - t1;
float dot00 = dot(v0, v0);
float dot01 = dot(v0, v1);
float dot02 = dot(v0, v2);
float dot11 = dot(v1, v1);
float dot12 = dot(v1, v2);
float invDenom = 1.0f / (dot00 * dot11 - dot01 * dot01);
float u = (dot11 * dot02 - dot01 * dot12) * invDenom;
float v = (dot00 * dot12 - dot01 * dot02) * invDenom;
return (u >= 0) && (v >= 0) && (u + v <= 1);
}
FloatRect FloatQuad::boundingBox() const
{
float left = min4(m_p1.x(), m_p2.x(), m_p3.x(), m_p4.x());
float top = min4(m_p1.y(), m_p2.y(), m_p3.y(), m_p4.y());
float right = max4(m_p1.x(), m_p2.x(), m_p3.x(), m_p4.x());
float bottom = max4(m_p1.y(), m_p2.y(), m_p3.y(), m_p4.y());
return FloatRect(left, top, right - left, bottom - top);
}
static inline bool withinEpsilon(float a, float b)
{
return fabs(a - b) < numeric_limits<float>::epsilon();
}
bool FloatQuad::isRectilinear() const
{
return (withinEpsilon(m_p1.x(), m_p2.x()) && withinEpsilon(m_p2.y(), m_p3.y()) && withinEpsilon(m_p3.x(), m_p4.x()) && withinEpsilon(m_p4.y(), m_p1.y()))
|| (withinEpsilon(m_p1.y(), m_p2.y()) && withinEpsilon(m_p2.x(), m_p3.x()) && withinEpsilon(m_p3.y(), m_p4.y()) && withinEpsilon(m_p4.x(), m_p1.x()));
}
bool FloatQuad::containsPoint(const FloatPoint& p) const
{
return isPointInTriangle(p, m_p1, m_p2, m_p3) || isPointInTriangle(p, m_p1, m_p3, m_p4);
}
bool FloatQuad::containsQuad(const FloatQuad& other) const
{
return containsPoint(other.p1()) && containsPoint(other.p2()) && containsPoint(other.p3()) && containsPoint(other.p4());
}
bool FloatQuad::isCounterclockwise() const
{
FloatPoint v1 = FloatPoint(m_p2.x() - m_p1.x(), m_p2.y() - m_p1.y());
FloatPoint v2 = FloatPoint(m_p3.x() - m_p2.x(), m_p3.y() - m_p2.y());
return (v1.x() * v2.y() - v1.y() * v2.x()) < 0;
}
}