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Use a label point for the general representative point for polygons

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(Skipping the iteration to find one that is as far as possible from
the borders)

This makes the labels look better in many cases (like France at z1)
but unfortunately ripples into changing the sequence of polygons in
many tests, so the diff is big.
This commit is contained in:
Erica Fischer
2022-10-07 12:11:12 -07:00
parent 2f0c9bf9c8
commit 2261adf05e
55 changed files with 25015 additions and 24803 deletions
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geometry.cpp
+30 -28
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@@ -1488,7 +1488,7 @@ double label_goodness(const drawvec &dv, size_t start, size_t count, long long x
// until something works well, or if nothing does after several iterations, use the
// least-bad option.
drawvec polygon_to_anchor(const drawvec &geom) {
drawvec polygon_to_anchor(const drawvec &geom, bool good) {
std::vector<polygon_label> labels;
drawvec dv;
@@ -1525,42 +1525,44 @@ drawvec polygon_to_anchor(const drawvec &geom) {
draw centroid(VT_MOVETO, xsum / count, ysum / count);
draw d = centerOfMass(geom, i, j, centroid);
double radius = sqrt(area / M_PI);
double goodness_threshold = radius / 5;
if (good) {
double radius = sqrt(area / M_PI);
double goodness_threshold = radius / 5;
double goodness = label_goodness(geom, i, j - i - 1, d.x, d.y);
if (goodness < goodness_threshold) {
// Label is too close to the border or outside it,
// so try some other possible points
double goodness = label_goodness(geom, i, j - i - 1, d.x, d.y);
if (goodness < goodness_threshold) {
// Label is too close to the border or outside it,
// so try some other possible points
for (long long sub = 2;
sub < 32 && (xmax - xmin) > 2 * sub && (ymax - ymin) > 2 * sub;
sub *= 2) {
for (long long x = 1; x < sub; x++) {
for (long long y = 1; y < sub; y++) {
draw maybe(VT_MOVETO,
xmin + x * (xmax - xmin) / sub,
ymin + y * (ymax - ymin) / sub);
for (long long sub = 2;
sub < 32 && (xmax - xmin) > 2 * sub && (ymax - ymin) > 2 * sub;
sub *= 2) {
for (long long x = 1; x < sub; x++) {
for (long long y = 1; y < sub; y++) {
draw maybe(VT_MOVETO,
xmin + x * (xmax - xmin) / sub,
ymin + y * (ymax - ymin) / sub);
double maybe_goodness = label_goodness(geom, i, j - i, maybe.x, maybe.y);
if (maybe_goodness > goodness) {
// better than the previous
d = maybe;
goodness = maybe_goodness;
double maybe_goodness = label_goodness(geom, i, j - i, maybe.x, maybe.y);
if (maybe_goodness > goodness) {
// better than the previous
d = maybe;
goodness = maybe_goodness;
}
}
}
if (goodness > goodness_threshold) {
break;
}
}
if (goodness > goodness_threshold) {
break;
// There is nothing really good. Is the centroid maybe better?
// If not, we're stuck with whatever the best we found was.
if (label_goodness(geom, i, j - i, centroid.x, centroid.y) > goodness) {
d = centroid;
}
}
// There is nothing really good. Is the centroid maybe better?
// If not, we're stuck with whatever the best we found was.
if (label_goodness(geom, i, j - i, centroid.x, centroid.y) > goodness) {
d = centroid;
}
}
polygon_label pl;