godot-module-template/engine/thirdparty/msdfgen/core/edge-selectors.h

118 lines
3 KiB
C++

#pragma once
#include "Vector2.hpp"
#include "SignedDistance.hpp"
#include "edge-segments.h"
namespace msdfgen {
struct MultiDistance {
double r, g, b;
};
struct MultiAndTrueDistance : MultiDistance {
double a;
};
/// Selects the nearest edge by its true distance.
class TrueDistanceSelector {
public:
typedef double DistanceType;
struct EdgeCache {
Point2 point;
double absDistance;
EdgeCache();
};
void reset(const Point2 &p);
void addEdge(EdgeCache &cache, const EdgeSegment *prevEdge, const EdgeSegment *edge, const EdgeSegment *nextEdge);
void merge(const TrueDistanceSelector &other);
DistanceType distance() const;
private:
Point2 p;
SignedDistance minDistance;
};
class PerpendicularDistanceSelectorBase {
public:
struct EdgeCache {
Point2 point;
double absDistance;
double aDomainDistance, bDomainDistance;
double aPerpendicularDistance, bPerpendicularDistance;
EdgeCache();
};
static bool getPerpendicularDistance(double &distance, const Vector2 &ep, const Vector2 &edgeDir);
PerpendicularDistanceSelectorBase();
void reset(double delta);
bool isEdgeRelevant(const EdgeCache &cache, const EdgeSegment *edge, const Point2 &p) const;
void addEdgeTrueDistance(const EdgeSegment *edge, const SignedDistance &distance, double param);
void addEdgePerpendicularDistance(double distance);
void merge(const PerpendicularDistanceSelectorBase &other);
double computeDistance(const Point2 &p) const;
SignedDistance trueDistance() const;
private:
SignedDistance minTrueDistance;
double minNegativePerpendicularDistance;
double minPositivePerpendicularDistance;
const EdgeSegment *nearEdge;
double nearEdgeParam;
};
/// Selects the nearest edge by its perpendicular distance.
class PerpendicularDistanceSelector : public PerpendicularDistanceSelectorBase {
public:
typedef double DistanceType;
void reset(const Point2 &p);
void addEdge(EdgeCache &cache, const EdgeSegment *prevEdge, const EdgeSegment *edge, const EdgeSegment *nextEdge);
DistanceType distance() const;
private:
Point2 p;
};
/// Selects the nearest edge for each of the three channels by its perpendicular distance.
class MultiDistanceSelector {
public:
typedef MultiDistance DistanceType;
typedef PerpendicularDistanceSelectorBase::EdgeCache EdgeCache;
void reset(const Point2 &p);
void addEdge(EdgeCache &cache, const EdgeSegment *prevEdge, const EdgeSegment *edge, const EdgeSegment *nextEdge);
void merge(const MultiDistanceSelector &other);
DistanceType distance() const;
SignedDistance trueDistance() const;
private:
Point2 p;
PerpendicularDistanceSelectorBase r, g, b;
};
/// Selects the nearest edge for each of the three color channels by its perpendicular distance and by true distance for the alpha channel.
class MultiAndTrueDistanceSelector : public MultiDistanceSelector {
public:
typedef MultiAndTrueDistance DistanceType;
DistanceType distance() const;
};
}