SkDLine Struct Reference

#include <SkPathOpsLine.h>

Public Member Functions
const SkDPoint &	operator[] (int n) const
SkDPoint &	operator[] (int n)
const SkDLine &	set (const SkPoint pts[2])
double	exactPoint (const SkDPoint &xy) const
double	nearPoint (const SkDPoint &xy, bool *unequal) const
bool	nearRay (const SkDPoint &xy) const
SkDPoint	ptAtT (double t) const
void	dump () const
void	dumpID (int) const
void	dumpInner () const

Static Public Member Functions
static double	ExactPointH (const SkDPoint &xy, double left, double right, double y)
static double	ExactPointV (const SkDPoint &xy, double top, double bottom, double x)
static double	NearPointH (const SkDPoint &xy, double left, double right, double y)
static double	NearPointV (const SkDPoint &xy, double top, double bottom, double x)

Public Attributes
SkDPoint	fPts [2]

Detailed Description

Definition at line 14 of file SkPathOpsLine.h.

Member Function Documentation

dump()

void SkDLine::dump

(

)

const

Definition at line 163 of file PathOpsDebug.cpp.

                         {
    this->dumpInner();
    SkDebugf("}},\n");
}

dumpID()

void SkDLine::dumpID

(

int

id

)

const

Definition at line 168 of file PathOpsDebug.cpp.

                                 {
    this->dumpInner();
    SkDebugf("}");
    DumpID(id);
}

dumpInner()

void SkDLine::dumpInner

(

)

const

Definition at line 174 of file PathOpsDebug.cpp.

                              {
    SkDebugf("{{");
    fPts[0].dump();
    SkDebugf(", ");
    fPts[1].dump();
}

exactPoint()

double SkDLine::exactPoint

(

const SkDPoint &

xy

)

const

Definition at line 26 of file SkPathOpsLine.cpp.

                                                   {
    if (xy == fPts[0]) {  // do cheapest test first
        return 0;
    }
    if (xy == fPts[1]) {
        return 1;
    }
    return -1;
}

ExactPointH()

double SkDLine::ExactPointH ( const SkDPoint &  xy, double  left, double  right, double  y  )

static

Definition at line 86 of file SkPathOpsLine.cpp.

                                                                                   {
    if (xy.fY == y) {
        if (xy.fX == left) {
            return 0;
        }
        if (xy.fX == right) {
            return 1;
        }
    }
    return -1;
}

ExactPointV()

double SkDLine::ExactPointV ( const SkDPoint &  xy, double  top, double  bottom, double  x  )

static

Definition at line 121 of file SkPathOpsLine.cpp.

                                                                                   {
    if (xy.fX == x) {
        if (xy.fY == top) {
            return 0;
        }
        if (xy.fY == bottom) {
            return 1;
        }
    }
    return -1;
}

nearPoint()

double SkDLine::nearPoint	(	const SkDPoint &	xy,
		bool *	unequal
	)		const

Definition at line 36 of file SkPathOpsLine.cpp.

                                                                 {
    if (!AlmostBetweenUlps(fPts[0].fX, xy.fX, fPts[1].fX)
            || !AlmostBetweenUlps(fPts[0].fY, xy.fY, fPts[1].fY)) {
        return -1;
    }
    // project a perpendicular ray from the point to the line; find the T on the line
    SkDVector len = fPts[1] - fPts[0]; // the x/y magnitudes of the line
    double denom = len.fX * len.fX + len.fY * len.fY;  // see DLine intersectRay
    SkDVector ab0 = xy - fPts[0];
    double numer = len.fX * ab0.fX + ab0.fY * len.fY;
    if (!between(0, numer, denom)) {
        return -1;
    }
    if (!denom) {
        return 0;
    }
    double t = numer / denom;
    SkDPoint realPt = ptAtT(t);
    double dist = realPt.distance(xy);   // OPTIMIZATION: can we compare against distSq instead ?
    // find the ordinal in the original line with the largest unsigned exponent
    double tiniest = std::min(std::min(std::min(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
    double largest = std::max(std::max(std::max(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
    largest = std::max(largest, -tiniest);
    if (!AlmostEqualUlps_Pin(largest, largest + dist)) { // is the dist within ULPS tolerance?
        return -1;
    }
    if (unequal) {
        *unequal = (float) largest != (float) (largest + dist);
    }
    t = SkPinT(t);  // a looser pin breaks skpwww_lptemp_com_3
    SkASSERT(between(0, t, 1));
    return t;
}

NearPointH()

double SkDLine::NearPointH ( const SkDPoint &  xy, double  left, double  right, double  y  )

static

Definition at line 98 of file SkPathOpsLine.cpp.

                                                                                  {
    if (!AlmostBequalUlps(xy.fY, y)) {
        return -1;
    }
    if (!AlmostBetweenUlps(left, xy.fX, right)) {
        return -1;
    }
    double t = (xy.fX - left) / (right - left);
    t = SkPinT(t);
    SkASSERT(between(0, t, 1));
    double realPtX = (1 - t) * left + t * right;
    SkDVector distU = {xy.fY - y, xy.fX - realPtX};
    double distSq = distU.fX * distU.fX + distU.fY * distU.fY;
    double dist = sqrt(distSq); // OPTIMIZATION: can we compare against distSq instead ?
    double tiniest = std::min(std::min(y, left), right);
    double largest = std::max(std::max(y, left), right);
    largest = std::max(largest, -tiniest);
    if (!AlmostEqualUlps(largest, largest + dist)) { // is the dist within ULPS tolerance?
        return -1;
    }
    return t;
}

NearPointV()

double SkDLine::NearPointV ( const SkDPoint &  xy, double  top, double  bottom, double  x  )

static

Definition at line 133 of file SkPathOpsLine.cpp.

                                                                                  {
    if (!AlmostBequalUlps(xy.fX, x)) {
        return -1;
    }
    if (!AlmostBetweenUlps(top, xy.fY, bottom)) {
        return -1;
    }
    double t = (xy.fY - top) / (bottom - top);
    t = SkPinT(t);
    SkASSERT(between(0, t, 1));
    double realPtY = (1 - t) * top + t * bottom;
    SkDVector distU = {xy.fX - x, xy.fY - realPtY};
    double distSq = distU.fX * distU.fX + distU.fY * distU.fY;
    double dist = sqrt(distSq); // OPTIMIZATION: can we compare against distSq instead ?
    double tiniest = std::min(std::min(x, top), bottom);
    double largest = std::max(std::max(x, top), bottom);
    largest = std::max(largest, -tiniest);
    if (!AlmostEqualUlps(largest, largest + dist)) { // is the dist within ULPS tolerance?
        return -1;
    }
    return t;
}

nearRay()

bool SkDLine::nearRay

(

const SkDPoint &

xy

)

const

Definition at line 70 of file SkPathOpsLine.cpp.

                                              {
    // project a perpendicular ray from the point to the line; find the T on the line
    SkDVector len = fPts[1] - fPts[0]; // the x/y magnitudes of the line
    double denom = len.fX * len.fX + len.fY * len.fY;  // see DLine intersectRay
    SkDVector ab0 = xy - fPts[0];
    double numer = len.fX * ab0.fX + ab0.fY * len.fY;
    double t = numer / denom;
    SkDPoint realPt = ptAtT(t);
    double dist = realPt.distance(xy);   // OPTIMIZATION: can we compare against distSq instead ?
    // find the ordinal in the original line with the largest unsigned exponent
    double tiniest = std::min(std::min(std::min(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
    double largest = std::max(std::max(std::max(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
    largest = std::max(largest, -tiniest);
    return RoughlyEqualUlps(largest, largest + dist); // is the dist within ULPS tolerance?
}

operator[]() [1/2]

SkDPoint & SkDLine::operator[] ( int  n )

inline

Definition at line 18 of file SkPathOpsLine.h.

{ SkASSERT(n >= 0 && n < 2); return fPts[n]; }

operator[]() [2/2]

const SkDPoint & SkDLine::operator[] ( int  n ) const

inline

Definition at line 17 of file SkPathOpsLine.h.

{ SkASSERT(n >= 0 && n < 2); return fPts[n]; }

ptAtT()

SkDPoint SkDLine::ptAtT

(

double

t

)

const

Definition at line 14 of file SkPathOpsLine.cpp.

                                      {
    if (0 == t) {
        return fPts[0];
    }
    if (1 == t) {
        return fPts[1];
    }
    double one_t = 1 - t;
    SkDPoint result = { one_t * fPts[0].fX + t * fPts[1].fX, one_t * fPts[0].fY + t * fPts[1].fY };
    return result;
}

set()

const SkDLine & SkDLine::set ( const SkPoint  pts[2] )

inline

Definition at line 20 of file SkPathOpsLine.h.

                                             {
        fPts[0] = pts[0];
        fPts[1] = pts[1];
        return *this;
    }

Member Data Documentation

fPts

SkDPoint SkDLine::fPts[2]

Definition at line 15 of file SkPathOpsLine.h.

---

The documentation for this struct was generated from the following files:

• third_party/skia/src/pathops/SkPathOpsLine.h
• third_party/skia/src/pathops/SkPathOpsLine.cpp
• third_party/skia/tests/PathOpsDebug.cpp