Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Fix a polygon clipping edge case #83

Merged
merged 1 commit into from
Oct 22, 2018
Merged

Fix a polygon clipping edge case #83

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 4 additions & 4 deletions include/mapbox/geojsonvt/clip.hpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -127,15 +127,15 @@ class clipper {

slice = newSlice(line);

} else if (bk >= k1) { // ---|--> |
} else if (bk > k1) { // ---|--> |
t = calc_progress<I>(a, b, k1);
slice.push_back(intersect<I>(a, b, k1, t));
if (lineMetrics) slice.segStart = lineLen + segLen * t;

if (i == len - 2)
slice.push_back(b); // last point
}
} else if (ak >= k2) {
} else if (ak > k2) {
if (bk < k1) { // <--|-----|---
t = calc_progress<I>(a, b, k2);
slice.push_back(intersect<I>(a, b, k2, t));
Expand Down Expand Up @@ -202,7 +202,7 @@ class clipper {
const double bk = get<I>(b);

if (ak < k1) {
if (bk >= k1) {
if (bk > k1) {
// ---|--> |
slice.push_back(intersect<I>(a, b, k1, calc_progress<I>(a, b, k1)));
if (bk > k2)
Expand All @@ -211,7 +211,7 @@ class clipper {
else if (i == len - 2)
slice.push_back(b); // last point
}
} else if (ak >= k2) {
} else if (ak > k2) {
if (bk < k2) { // | <--|---
slice.push_back(intersect<I>(a, b, k2, calc_progress<I>(a, b, k2)));
if (bk < k1) // <--|-----|---
Expand Down
10 changes: 10 additions & 0 deletions test/fixtures/polygon-bug.json
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,10 @@
{
"type": "Polygon",
"coordinates": [[
[42.1875, 57.32652122521708],
[47.8125, 57.32652122521708],
[47.8125, 54.16243396806781],
[42.1875, 54.16243396806781],
[42.1875, 57.32652122521708]
]]
}
21 changes: 21 additions & 0 deletions test/test.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -243,6 +243,27 @@ TEST(GetTile, AntimeridianTriangle) {
}
}

TEST(GetTile, PolygonClippingBug) {
const auto geojson = mapbox::geojson::parse(loadFile("test/fixtures/polygon-bug.json"));

Options options;
options.buffer = 1024;

GeoJSONVT index{ geojson, options };

auto tile = index.getTile(5, 19, 9);
ASSERT_EQ(tile.features.size(), 1);
ASSERT_EQ(tile.num_points, 5);

const mapbox::geometry::polygon<int16_t> expected{
{ {3072, 3072}, {5120, 3072}, {5120, 5120}, {3072, 5120}, {3072, 3072} }
};

const auto actual = tile.features[0].geometry.get<mapbox::geometry::polygon<int16_t>>();

ASSERT_EQ(actual, expected);
}

TEST(GetTile, Projection) {
const auto geojson = mapbox::geojson::parse(loadFile("test/fixtures/linestring.json"));

Expand Down