double SkDLine::nearPoint(const SkDPoint& xy) const {
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;
}
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 = SkTMin(SkTMin(SkTMin(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
double largest = SkTMax(SkTMax(SkTMax(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
largest = SkTMax(largest, -tiniest);
if (!AlmostEqualUlps(largest, largest + dist)) { // is the dist within ULPS tolerance?
return -1;
}
t = SkPinT(t);
SkASSERT(between(0, t, 1));
return t;
}
bool SkDLine::nearRay(const SkDPoint& xy) const {
// 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 = SkTMin(SkTMin(SkTMin(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
double largest = SkTMax(SkTMax(SkTMax(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
largest = SkTMax(largest, -tiniest);
return RoughlyEqualUlps(largest, largest + dist); // is the dist within ULPS tolerance?
}
static void pointFinder(const SkDQuad& q1, const SkDQuad& q2) {
for (int index = 0; index < 3; ++index) {
double t = q1.nearestT(q2[index]);
SkDPoint onQuad = q1.ptAtT(t);
SkDebugf("%s t=%1.9g (%1.9g,%1.9g) dist=%1.9g\n", __FUNCTION__, t, onQuad.fX, onQuad.fY,
onQuad.distance(q2[index]));
double left[3];
left[0] = ((const SkDLine&) q1[0]).isLeft(q2[index]);
left[1] = ((const SkDLine&) q1[1]).isLeft(q2[index]);
SkDLine diag = {{q1[0], q1[2]}};
left[2] = diag.isLeft(q2[index]);
SkDebugf("%s left=(%d, %d, %d) inHull=%s\n", __FUNCTION__, floatSign(left[0]),
floatSign(left[1]), floatSign(left[2]),
q1.pointInHull(q2[index]) ? "true" : "false");
}
SkDebugf("\n");
}
