Files
rdkit/Code/GraphMol/MolDraw2D/MolDraw2DDetails.cpp
Chris Von Bargen d8f4afb558 Add getSGroupDataLabels() to MolDraw2D_detail namespace (#9189)
Adds a new function MolDraw2D_detail::getSGroupDataLabels() that returns
the text and molecule-coordinate positions of DAT SGroup labels, using
the same placement logic as the drawing code. This allows external
renderers to display SGroup labels consistently with RDKit's placement.

Refactors DrawMol::extractSGroupData() to call getSGroupDataLabels()
internally, eliminating the duplicate FIELDDISP parsing and position
computation logic.

Closes #7829

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-04-16 04:56:00 +02:00

529 lines
17 KiB
C++

//
// Copyright (C) 2015-2020 Greg Landrum
//
// @@ All Rights Reserved @@
// This file is part of the RDKit.
// The contents are covered by the terms of the BSD license
// which is included in the file license.txt, found at the root
// of the RDKit source tree.
//
#include <GraphMol/MolDraw2D/MolDraw2DDetails.h>
#include <GraphMol/MolDraw2D/StringRect.h>
#include <GraphMol/Chirality.h>
#include <GraphMol/FileParsers/FileParserUtils.h>
#include <GraphMol/SubstanceGroup.h>
#include <Geometry/Transform2D.h>
#include <RDGeneral/types.h>
#include <cmath>
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
// ****************************************************************************
namespace RDKit {
namespace MolDraw2D_detail {
// implementation from $RDBASE/rdkit/sping/pid.py
void arcPoints(const Point2D &cds1, const Point2D &cds2,
std::vector<Point2D> &res, float startAng, float extent) {
// Note: this implementation is simple and not particularly efficient.
float xScale = (cds2.x - cds1.x) / 2.0;
float yScale = (cds2.y - cds1.y) / 2.0;
if (xScale < 0) {
xScale *= -1;
}
if (yScale < 0) {
yScale *= -1;
}
float x = std::min(cds1.x, cds2.x) + xScale;
float y = std::min(cds1.y, cds2.y) + yScale;
int steps = std::max(static_cast<int>(extent * 2), 5);
float step = M_PI * extent / (180 * steps);
float angle = M_PI * startAng / 180;
for (int i = 0; i <= steps; ++i) {
Point2D point(x + xScale * cos(angle), y - yScale * sin(angle));
res.emplace_back(point);
angle += step;
}
}
namespace {
// note, this is approximate since we're just using it for drawing
bool lineSegmentsIntersect(const Point2D &s1, const Point2D &s2,
const Point2D &s3, const Point2D &s4) {
auto d1x = (s1.x - s2.x);
auto d1y = (s1.y - s2.y);
auto d2x = (s3.x - s4.x);
auto d2y = (s3.y - s4.y);
if (fabs(d1x) < 1e-4) {
// fudge factor, since this isn't super critical
d1x = 1e-4;
}
if (fabs(d2x) < 1e-4) {
// fudge factor, since this isn't super critical
d2x = 1e-4;
}
auto m1 = d1y / d1x;
auto m2 = d2y / d2x;
if (m1 == m2 || m1 == -m2) {
// parallel
return false;
}
auto b1 = (s1.x * s2.y - s2.x * s1.y) / d1x;
auto b2 = (s3.x * s4.y - s4.x * s3.y) / d2x;
auto intersectX = (b2 - b1) / (m1 - m2);
return ((intersectX < s1.x) ^ (intersectX < s2.x)) &&
((intersectX < s3.x) ^ (intersectX < s4.x));
}
} // namespace
std::vector<Point2D> getBracketPoints(
const Point2D &p1, const Point2D &p2, const Point2D &refPt,
const std::vector<std::pair<Point2D, Point2D>> &bondSegments,
double bracketFrac) {
std::vector<Point2D> res;
auto v = p2 - p1;
Point2D bracketDir{v.y, -v.x};
bracketDir *= bracketFrac;
// we'll default to use the refPt
auto refVect = p2 - refPt;
// but check if we intersect any of the bonds:
for (const auto &seg : bondSegments) {
if (lineSegmentsIntersect(p1, p2, seg.first, seg.second)) {
refVect = p2 - seg.first;
}
}
if (bracketDir.dotProduct(refVect) > 0) {
bracketDir *= -1;
}
auto p0 = p1 + bracketDir;
auto p3 = p2 + bracketDir;
return {p0, p1, p2, p3};
}
// there are a several empirically determined constants here.
std::vector<Point2D> handdrawnLine(Point2D cds1, Point2D cds2, double scale,
bool shiftBegin, bool shiftEnd,
unsigned nSteps, double deviation,
double endShift) {
// std::cout << " " << scale << " " << endShift / scale << std::endl;
while (endShift / scale > 0.02) {
endShift *= 0.75;
}
if (shiftBegin) {
cds1.x += (std::rand() % 10 >= 5 ? endShift : -endShift) / scale;
cds1.y += (std::rand() % 10 >= 5 ? endShift : -endShift) / scale;
}
if (shiftEnd) {
cds2.x += (std::rand() % 10 >= 5 ? endShift : -endShift) / scale;
cds2.y += (std::rand() % 10 >= 5 ? endShift : -endShift) / scale;
}
Point2D step = (cds2 - cds1) / nSteps;
// make sure we aren't adding loads of wiggles to short lines
while (step.length() < 0.2 && nSteps > 2) {
--nSteps;
step = (cds2 - cds1) / nSteps;
}
// make sure the wiggles aren't too big
while (deviation / step.length() > 0.15 || deviation * scale > 0.70) {
deviation *= 0.75;
}
Point2D perp{step.y, -step.x};
perp.normalize();
std::vector<Point2D> pts;
pts.push_back(cds1);
for (unsigned int i = 1; i < nSteps; ++i) {
auto tgt = cds1 + step * i;
tgt += perp * deviation * (std::rand() % 20 - 10) / 10.0;
pts.push_back(tgt);
}
pts.push_back(cds2);
return pts;
}
// ****************************************************************************
bool doesLineIntersect(const StringRect &rect, const Point2D &end1,
const Point2D &end2, double padding) {
Point2D tl, tr, bl, br;
rect.calcCorners(tl, tr, br, bl, padding);
if (doLinesIntersect(end2, end1, tl, tr, nullptr)) {
return true;
}
if (doLinesIntersect(end2, end1, tr, br, nullptr)) {
return true;
}
if (doLinesIntersect(end2, end1, br, bl, nullptr)) {
return true;
}
if (doLinesIntersect(end2, end1, bl, tl, nullptr)) {
return true;
}
return false;
}
// ****************************************************************************
bool doesTriangleIntersect(const StringRect &rect, const Point2D &pt1,
const Point2D &pt2, const Point2D &pt3,
double padding) {
// the quick test is for any of the triangle points inside the rectangle.
if (rect.isPointInside(pt1, padding) || rect.isPointInside(pt2, padding) ||
rect.isPointInside(pt3, padding)) {
return true;
}
// But if the rectangle is inside the triangle, that's not enough of a test.
Point2D tl, tr, br, bl;
rect.calcCorners(tl, tr, br, bl, padding);
if (isPointInTriangle(tl, pt1, pt2, pt3) ||
isPointInTriangle(tr, pt1, pt2, pt3) ||
isPointInTriangle(br, pt1, pt2, pt3) ||
isPointInTriangle(bl, pt1, pt2, pt3)) {
return true;
}
// and finally all the points in the rectangle can be outside the triangle,
// but the sides can cross it. And vice versa. So see if any of the sides
// intersect.
if (doLinesIntersect(tl, tr, pt1, pt2, nullptr) ||
doLinesIntersect(tl, tr, pt2, pt3, nullptr) ||
doLinesIntersect(tl, tr, pt3, pt1, nullptr) ||
doLinesIntersect(tr, br, pt1, pt2, nullptr) ||
doLinesIntersect(tr, br, pt2, pt3, nullptr) ||
doLinesIntersect(tr, br, pt3, pt1, nullptr) ||
doLinesIntersect(br, bl, pt1, pt2, nullptr) ||
doLinesIntersect(br, bl, pt2, pt3, nullptr) ||
doLinesIntersect(br, bl, pt3, pt1, nullptr) ||
doLinesIntersect(bl, tl, pt1, pt2, nullptr) ||
doLinesIntersect(bl, tl, pt2, pt3, nullptr) ||
doLinesIntersect(bl, tl, pt3, pt1, nullptr)) {
return true;
}
return false;
}
// ****************************************************************************
bool doesLineIntersectEllipse(const Point2D &centre, double xradius,
double yradius, double padding,
const Point2D &end1, const Point2D &end2) {
// using
// https://math.stackexchange.com/questions/76457/check-if-a-point-is-within-an-ellipse
// to see if either end1 or end2 are inside the ellipse.
double xr2 = (xradius + padding) * (xradius + padding);
double yr2 = (yradius + padding) * (yradius + padding);
double xdisc = (end1.x - centre.x) * (end1.x - centre.x) / xr2;
double ydisc = (end1.y - centre.y) * (end1.y - centre.y) / yr2;
if (xdisc + ydisc <= 1.0) {
return true;
}
xdisc = (end2.x - centre.x) * (end2.x - centre.x) / xr2;
ydisc = (end2.y - centre.y) * (end2.y - centre.y) / yr2;
return xdisc + ydisc <= 1.0;
}
// ****************************************************************************
bool doesLineIntersectArc(const Point2D &centre, double xradius, double yradius,
double start_ang, double stop_ang, double padding,
const Point2D &end1, const Point2D &end2) {
double xr = xradius + padding;
double yr = yradius + padding;
double xr2 = xr * xr;
double yr2 = yr * yr;
auto pointInArc = [&](const Point2D &p) -> bool {
double xdisc = p.x * p.x / xr2;
double ydisc = p.y * p.y / yr2;
// start_ang can be more than stop_ang, if, for example, the arc goes from
// 315 to 45.
if (xdisc + ydisc <= 1.0) {
// end1 is inside the whole ellipse. See if the angle it makes with the
// x axis lies between start_and and stop_ang.
double th = atan2(p.x, p.y) * 180.0 / M_PI;
if (th < 0.0) {
th += 360.0;
}
if (start_ang < stop_ang) {
// it's pretty straightforward
if (th >= start_ang && th <= stop_ang) {
return true;
}
} else {
// the arc crosses 0.
if (th >= start_ang && th <= 360.0) {
return true;
}
if (th >= 0.0 && th <= stop_ang) {
return true;
}
}
}
return false;
};
Point2D p1 = end1 - centre;
if (pointInArc(p1)) {
return true;
}
Point2D p2 = end2 - centre;
return pointInArc(p2);
}
// ****************************************************************************
bool doLinesIntersect(const Point2D &l1s, const Point2D &l1f,
const Point2D &l2s, const Point2D &l2f, Point2D *ip) {
// using spell from answer 2 of
// https://stackoverflow.com/questions/563198/how-do-you-detect-where-two-line-segments-intersect
double s1_x = l1f.x - l1s.x;
double s1_y = l1f.y - l1s.y;
double s2_x = l2f.x - l2s.x;
double s2_y = l2f.y - l2s.y;
double d = (-s2_x * s1_y + s1_x * s2_y);
if (d == 0.0) {
// parallel lines.
return false;
}
double s, t;
s = (-s1_y * (l1s.x - l2s.x) + s1_x * (l1s.y - l2s.y)) / d;
t = (s2_x * (l1s.y - l2s.y) - s2_y * (l1s.x - l2s.x)) / d;
if (s >= 0 && s <= 1 && t >= 0 && t <= 1) {
if (ip) {
ip->x = l1s.x + t * s1_x;
ip->y = l1s.y + t * s1_y;
}
return true;
}
return false;
}
// ****************************************************************************
bool isPointInTriangle(const Point2D &pt, const Point2D &t1, const Point2D &t2,
const Point2D &t3) {
double d = ((t2.y - t3.y) * (t1.x - t3.x) + (t3.x - t2.x) * (t1.y - t3.y));
double a =
((t2.y - t3.y) * (pt.x - t3.x) + (t3.x - t2.x) * (pt.y - t3.y)) / d;
double b =
((t3.y - t1.y) * (pt.x - t3.x) + (t1.x - t3.x) * (pt.y - t3.y)) / d;
double c = 1 - a - b;
return 0 <= a && a <= 1 && 0 <= b && b <= 1 && 0 <= c && c <= 1;
}
std::vector<std::tuple<Point2D, Point2D, Point2D, Point2D>> getWavyLineSegments(
const Point2D &p1, const Point2D &p2, unsigned int nSegments,
double vertOffset) {
std::vector<std::tuple<Point2D, Point2D, Point2D, Point2D>> res;
PRECONDITION(nSegments > 1, "too few segments");
if (nSegments % 2) {
++nSegments; // we're going to assume an even number of segments
}
Point2D delta = (p2 - p1);
Point2D perp(delta.y, -delta.x);
perp.normalize();
perp *= vertOffset;
delta /= nSegments;
for (unsigned int i = 0; i < nSegments; ++i) {
Point2D startpt = p1 + delta * i;
Point2D segpt = startpt + delta;
Point2D cpt1 = startpt + perp * (i % 2 ? -1 : 1);
Point2D cpt2 = segpt + perp * (i % 2 ? -1 : 1);
res.emplace_back(startpt, cpt1, cpt2, segpt);
}
return res;
}
RDKIT_MOLDRAW2D_EXPORT void calcArrowHead(Point2D &arrowEnd, Point2D &arrow1,
Point2D &arrow2,
const Point2D &arrowBegin,
double frac, double lineWidth,
double angle) {
if (angle < 1.0e-6) {
return;
}
// Allow for the mitre.
double adjuster = 0.5 * lineWidth / sin(angle);
double len = (arrowBegin - arrowEnd).length();
if (len > 1.0e-6) {
double adjLen = len - adjuster;
arrowEnd.x = arrowBegin.x + (arrowEnd.x - arrowBegin.x) * adjLen / len;
arrowEnd.y = arrowBegin.y + (arrowEnd.y - arrowBegin.y) * adjLen / len;
}
auto delta = arrowBegin - arrowEnd;
double cos_angle = std::cos(angle), sin_angle = std::sin(angle);
// To have the arrowhead a consistent fraction of the line length, we need
// the hypotenuse.
frac /= cos_angle;
arrow1 = arrowEnd;
arrow1.x += frac * (delta.x * cos_angle + delta.y * sin_angle);
arrow1.y += frac * (delta.y * cos_angle - delta.x * sin_angle);
arrow2 = arrowEnd;
arrow2.x += frac * (delta.x * cos_angle - delta.y * sin_angle);
arrow2.y += frac * (delta.y * cos_angle + delta.x * sin_angle);
}
// ****************************************************************************
void adjustLineEndForEllipse(const Point2D &centre, double xradius,
double yradius, Point2D p1, Point2D &p2) {
// move everything so the ellipse is centred on the origin.
p1 -= centre;
p2 -= centre;
double a2 = xradius * xradius;
double b2 = yradius * yradius;
double A =
(p2.x - p1.x) * (p2.x - p1.x) / a2 + (p2.y - p1.y) * (p2.y - p1.y) / b2;
double B = 2.0 * p1.x * (p2.x - p1.x) / a2 + 2.0 * p1.y * (p2.y - p1.y) / b2;
double C = p1.x * p1.x / a2 + p1.y * p1.y / b2 - 1.0;
auto t_to_point = [&](double t) -> Point2D {
Point2D ret_val;
ret_val.x = p1.x + (p2.x - p1.x) * t + centre.x;
ret_val.y = p1.y + (p2.y - p1.y) * t + centre.y;
return ret_val;
};
double disc = B * B - 4.0 * A * C;
if (disc < 0.0) {
// no solutions, leave things as they are. Bit crap, though.
p2 += centre;
return;
} else if (fabs(disc) < 1.0e-6) {
// 1 solution
double t = -B / (2.0 * A);
p2 = t_to_point(t);
} else {
// 2 solutions - take the one nearest p1.
double disc_rt = sqrt(disc);
double t1 = (-B + disc_rt) / (2.0 * A);
double t2 = (-B - disc_rt) / (2.0 * A);
double t;
// prefer the t between 0 and 1, as that must be between the original
// points. If both are, prefer the lower, as that will be nearest p1,
// so on the bit of the ellipse the line comes to first.
bool t1_ok = (t1 >= 0.0 && t1 <= 1.0);
bool t2_ok = (t2 >= 0.0 && t2 <= 1.0);
if (t1_ok && !t2_ok) {
t = t1;
} else if (t2_ok && !t1_ok) {
t = t2;
} else if (t1_ok && t2_ok) {
t = std::min(t1, t2);
} else {
// the intersections are both outside the line between p1 and p2
// so don't do anything.
p2 += centre;
return;
}
p2 = t_to_point(t);
}
}
// ****************************************************************************
std::vector<SGroupDataLabel> getSGroupDataLabels(const ROMol &mol,
double rotate) {
std::vector<SGroupDataLabel> result;
if (!mol.getNumConformers()) {
return result;
}
const auto &sgs = getSubstanceGroups(mol);
if (sgs.empty()) {
return result;
}
double rot = rotate * M_PI / 180.0;
RDGeom::Transform2D tform;
tform.SetTransform(Point2D(0.0, 0.0), rot);
const auto &conf = mol.getConformer();
for (const auto &sg : sgs) {
std::string typ;
if (!sg.getPropIfPresent("TYPE", typ) || typ != "DAT") {
continue;
}
std::string text;
if (sg.hasProp("DATAFIELDS")) {
STR_VECT dfs = sg.getProp<STR_VECT>("DATAFIELDS");
for (const auto &df : dfs) {
text += df + "|";
}
text.pop_back();
}
if (text.empty()) {
continue;
}
int atomIdx = -1;
if (!sg.getAtoms().empty()) {
atomIdx = sg.getAtoms()[0];
}
bool located = false;
std::string fieldDisp;
Point2D pos(0.0, 0.0);
if (sg.getPropIfPresent("FIELDDISP", fieldDisp)) {
double xp =
FileParserUtils::stripSpacesAndCast<double>(fieldDisp.substr(0, 10));
double yp =
FileParserUtils::stripSpacesAndCast<double>(fieldDisp.substr(10, 10));
// we always invert y for the molecule coords
pos = Point2D{xp, -yp};
if (fieldDisp[25] == 'R') {
if (atomIdx < 0) {
// no atom to anchor relative position to, skip
continue;
} else if (fabs(xp) > 1e-3 || fabs(yp) > 1e-3) {
// opposite sign for y
pos.x += conf.getAtomPos(atomIdx).x;
pos.y -= conf.getAtomPos(atomIdx).y;
located = true;
}
} else {
// Absolute position - check for centroid offset set by drawing pipeline
if (mol.hasProp("_centroidx")) {
Point2D centroid;
mol.getProp("_centroidx", centroid.x);
mol.getProp("_centroidy", centroid.y);
// opposite sign for y
pos.x += centroid.x;
pos.y -= centroid.y;
}
located = true;
}
tform.TransformPoint(pos);
}
if (!located) {
if (atomIdx >= 0) {
const auto &p = conf.getAtomPos(atomIdx);
pos = Point2D{p.x, p.y};
} else {
BOOST_LOG(rdWarningLog)
<< "FIELDDISP info not found for DAT SGroup which isn't "
"associated with an atom. SGroup will not be included."
<< std::endl;
continue;
}
}
result.push_back({text, pos, located, atomIdx});
}
return result;
}
} // namespace MolDraw2D_detail
} // namespace RDKit