mirror of
https://github.com/felt/tippecanoe.git
synced 2026-10-02 16:35:40 +02:00
Put all of this back in geometry.cpp for conflict resolution
This commit is contained in:
Erica Fischer
+576
@@ -12,6 +12,8 @@
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#include <sqlite3.h>
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#include <mapbox/geometry/point.hpp>
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#include <mapbox/geometry/multi_polygon.hpp>
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#include <mapbox/geometry/wagyu/wagyu.hpp>
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#include <mapbox/geometry/wagyu/quick_clip.hpp>
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#include <mapbox/geometry/snap_rounding.hpp>
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#include "geometry.hpp"
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#include "projection.hpp"
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@@ -79,6 +81,342 @@ drawvec decode_geometry(char **meta, int z, unsigned tx, unsigned ty, long long
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return out;
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}
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// @@@
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void to_tile_scale(drawvec &geom, int z, int detail) {
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if (32 - detail - z < 0) {
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for (size_t i = 0; i < geom.size(); i++) {
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geom[i].x = std::round((double) geom[i].x * (1LL << (-(32 - detail - z))));
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geom[i].y = std::round((double) geom[i].y * (1LL << (-(32 - detail - z))));
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}
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} else {
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for (size_t i = 0; i < geom.size(); i++) {
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geom[i].x = std::round((double) geom[i].x / (1LL << (32 - detail - z)));
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geom[i].y = std::round((double) geom[i].y / (1LL << (32 - detail - z)));
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}
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}
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}
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drawvec from_tile_scale(drawvec const &geom, int z, int detail) {
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drawvec out;
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for (size_t i = 0; i < geom.size(); i++) {
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draw d = geom[i];
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d.x *= (1LL << (32 - detail - z));
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d.y *= (1LL << (32 - detail - z));
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out.push_back(d);
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}
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return out;
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}
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drawvec remove_noop(drawvec geom, int type, int shift) {
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// first pass: remove empty linetos
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long long x = 0, y = 0;
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drawvec out;
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for (size_t i = 0; i < geom.size(); i++) {
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if (geom[i].op == VT_LINETO && (long long) std::round((double) geom[i].x / (1LL << shift)) == x && (long long) std::round((double) geom[i].y / (1LL << shift)) == y) {
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continue;
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}
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if (geom[i].op == VT_CLOSEPATH) {
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out.push_back(geom[i]);
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} else { /* moveto or lineto */
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out.push_back(geom[i]);
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x = std::round((double) geom[i].x / (1LL << shift));
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y = std::round((double) geom[i].y / (1LL << shift));
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}
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}
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// second pass: remove unused movetos
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if (type != VT_POINT) {
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geom = out;
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out.resize(0);
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for (size_t i = 0; i < geom.size(); i++) {
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if (geom[i].op == VT_MOVETO) {
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if (i + 1 >= geom.size()) {
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continue;
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}
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if (geom[i + 1].op == VT_MOVETO) {
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continue;
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}
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if (geom[i + 1].op == VT_CLOSEPATH) {
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fprintf(stderr, "Shouldn't happen\n");
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i++; // also remove unused closepath
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continue;
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}
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}
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out.push_back(geom[i]);
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}
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}
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// second pass: remove empty movetos
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if (type == VT_LINE) {
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geom = out;
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out.resize(0);
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for (size_t i = 0; i < geom.size(); i++) {
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if (geom[i].op == VT_MOVETO) {
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if (i > 0 && geom[i - 1].op == VT_LINETO && (long long) std::round((double) geom[i - 1].x / (1LL << shift)) == (long long) std::round((double) geom[i].x / (1LL << shift)) && (long long) std::round((double) geom[i - 1].y / (1LL << shift)) == (long long) std::round((double) geom[i].y / (1LL << shift))) {
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continue;
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}
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}
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out.push_back(geom[i]);
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}
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}
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return out;
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}
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double get_area_scaled(const drawvec &geom, size_t i, size_t j) {
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const double max_exact_double = (double) ((1LL << 53) - 1);
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// keep scaling the geometry down until we can calculate its area without overflow
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for (long long scale = 2; scale < (1LL << 30); scale *= 2) {
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long long bx = geom[i].x;
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long long by = geom[i].y;
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bool again = false;
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// https://en.wikipedia.org/wiki/Shoelace_formula
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double area = 0;
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for (size_t k = i; k < j; k++) {
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area += (double) ((geom[k].x - bx) / scale) * (double) ((geom[i + ((k - i + 1) % (j - i))].y - by) / scale);
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if (std::fabs(area) >= max_exact_double) {
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again = true;
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break;
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}
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area -= (double) ((geom[k].y - by) / scale) * (double) ((geom[i + ((k - i + 1) % (j - i))].x - bx) / scale);
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if (std::fabs(area) >= max_exact_double) {
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again = true;
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break;
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}
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}
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if (again) {
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continue;
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} else {
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area /= 2;
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return area * scale * scale;
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}
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}
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fprintf(stderr, "get_area_scaled: can't happen\n");
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exit(EXIT_IMPOSSIBLE);
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}
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double get_area(const drawvec &geom, size_t i, size_t j) {
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const double max_exact_double = (double) ((1LL << 53) - 1);
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// Coordinates in `geom` are 40-bit integers, so there is no good way
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// to multiply them without possible precision loss. Since they probably
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// do not use the full precision, shift them nearer to the origin so
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// their product is more likely to be exactly representable as a double.
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//
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// (In practice they are actually 34-bit integers: 32 bits for the
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// Mercator world plane, plus another two bits so features can stick
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// off either the left or right side. But that is still too many bits
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// for the product to fit either in a 64-bit long long or in a
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// double where the largest exact integer is 2^53.)
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//
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// If the intermediate calculation still exceeds 2^53, start trying to
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// recalculate the area by scaling down the geometry. This will not
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// produce as precise an area, but it will still be close, and the
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// sign will be correct, which is more important, since the sign
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// determines the winding order of the rings. We can then use that
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// sign with this generally more precise area calculation.
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long long bx = geom[i].x;
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long long by = geom[i].y;
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// https://en.wikipedia.org/wiki/Shoelace_formula
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double area = 0;
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bool overflow = false;
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for (size_t k = i; k < j; k++) {
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area += (double) (geom[k].x - bx) * (double) (geom[i + ((k - i + 1) % (j - i))].y - by);
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if (std::fabs(area) >= max_exact_double) {
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overflow = true;
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}
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area -= (double) (geom[k].y - by) * (double) (geom[i + ((k - i + 1) % (j - i))].x - bx);
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if (std::fabs(area) >= max_exact_double) {
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overflow = true;
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}
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}
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area /= 2;
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if (overflow) {
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double scaled_area = get_area_scaled(geom, i, j);
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if ((area < 0 && scaled_area > 0) || (area > 0 && scaled_area < 0)) {
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area = -area;
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}
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}
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return area;
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}
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double get_mp_area(drawvec &geom) {
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double ret = 0;
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for (size_t i = 0; i < geom.size(); i++) {
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if (geom[i].op == VT_MOVETO) {
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size_t j;
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for (j = i + 1; j < geom.size(); j++) {
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if (geom[j].op != VT_LINETO) {
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break;
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}
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}
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ret += get_area(geom, i, j);
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i = j - 1;
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}
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}
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return ret;
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}
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/// @@@
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/// @@@
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static void decode_clipped(mapbox::geometry::multi_polygon<long long> &t, drawvec &out) {
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out.clear();
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for (size_t i = 0; i < t.size(); i++) {
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for (size_t j = 0; j < t[i].size(); j++) {
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drawvec ring;
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for (size_t k = 0; k < t[i][j].size(); k++) {
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ring.push_back(draw((k == 0) ? VT_MOVETO : VT_LINETO, t[i][j][k].x, t[i][j][k].y));
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}
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if (ring.size() > 0 && ring[ring.size() - 1] != ring[0]) {
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fprintf(stderr, "Had to close ring\n");
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ring.push_back(draw(VT_LINETO, ring[0].x, ring[0].y));
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}
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double area = get_area(ring, 0, ring.size());
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if ((j == 0 && area < 0) || (j != 0 && area > 0)) {
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fprintf(stderr, "Ring area has wrong sign: %f for %zu\n", area, j);
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exit(EXIT_IMPOSSIBLE);
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}
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for (size_t k = 0; k < ring.size(); k++) {
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out.push_back(ring[k]);
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}
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}
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}
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}
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drawvec clean_or_clip_poly(drawvec &geom, int z, int buffer, bool clip) {
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mapbox::geometry::wagyu::wagyu<long long> wagyu;
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geom = remove_noop(geom, VT_POLYGON, 0);
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for (size_t i = 0; i < geom.size(); i++) {
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if (geom[i].op == VT_MOVETO) {
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size_t j;
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for (j = i + 1; j < geom.size(); j++) {
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if (geom[j].op != VT_LINETO) {
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break;
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}
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}
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if (j >= i + 4) {
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mapbox::geometry::linear_ring<long long> lr;
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for (size_t k = i; k < j; k++) {
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lr.push_back(mapbox::geometry::point<long long>(geom[k].x, geom[k].y));
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}
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if (lr.size() >= 3) {
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wagyu.add_ring(lr);
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}
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}
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i = j - 1;
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}
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}
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if (clip) {
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long long area = 0xFFFFFFFF;
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if (z != 0) {
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area = 1LL << (32 - z);
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}
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long long clip_buffer = buffer * area / 256;
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mapbox::geometry::linear_ring<long long> lr;
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lr.push_back(mapbox::geometry::point<long long>(-clip_buffer, -clip_buffer));
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lr.push_back(mapbox::geometry::point<long long>(-clip_buffer, area + clip_buffer));
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lr.push_back(mapbox::geometry::point<long long>(area + clip_buffer, area + clip_buffer));
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lr.push_back(mapbox::geometry::point<long long>(area + clip_buffer, -clip_buffer));
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lr.push_back(mapbox::geometry::point<long long>(-clip_buffer, -clip_buffer));
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wagyu.add_ring(lr, mapbox::geometry::wagyu::polygon_type_clip);
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}
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mapbox::geometry::multi_polygon<long long> result;
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try {
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wagyu.execute(mapbox::geometry::wagyu::clip_type_union, result, mapbox::geometry::wagyu::fill_type_positive, mapbox::geometry::wagyu::fill_type_positive);
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} catch (std::runtime_error &e) {
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FILE *f = fopen("/tmp/wagyu.log", "w");
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fprintf(f, "%s\n", e.what());
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fprintf(stderr, "%s\n", e.what());
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fprintf(f, "[");
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for (size_t i = 0; i < geom.size(); i++) {
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if (geom[i].op == VT_MOVETO) {
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size_t j;
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for (j = i + 1; j < geom.size(); j++) {
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if (geom[j].op != VT_LINETO) {
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break;
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}
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}
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if (j >= i + 4) {
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mapbox::geometry::linear_ring<long long> lr;
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if (i != 0) {
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fprintf(f, ",");
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}
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fprintf(f, "[");
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for (size_t k = i; k < j; k++) {
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lr.push_back(mapbox::geometry::point<long long>(geom[k].x, geom[k].y));
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if (k != i) {
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fprintf(f, ",");
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}
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fprintf(f, "[%lld,%lld]", geom[k].x, geom[k].y);
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}
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fprintf(f, "]");
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if (lr.size() >= 3) {
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}
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}
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i = j - 1;
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}
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}
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fprintf(f, "]");
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fprintf(f, "\n\n\n\n\n");
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fclose(f);
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fprintf(stderr, "Internal error: Polygon cleaning failed. Log in /tmp/wagyu.log\n");
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exit(EXIT_IMPOSSIBLE);
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}
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drawvec ret;
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decode_clipped(result, ret);
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return ret;
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}
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// @@@
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/* pnpoly:
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Copyright (c) 1970-2003, Wm. Randolph Franklin
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@@ -186,6 +524,94 @@ void check_polygon(drawvec &geom) {
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}
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}
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// @@@
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drawvec close_poly(drawvec &geom) {
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drawvec out;
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for (size_t i = 0; i < geom.size(); i++) {
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if (geom[i].op == VT_MOVETO) {
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size_t j;
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for (j = i + 1; j < geom.size(); j++) {
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if (geom[j].op != VT_LINETO) {
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break;
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}
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}
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if (j - 1 > i) {
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if (geom[j - 1].x != geom[i].x || geom[j - 1].y != geom[i].y) {
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fprintf(stderr, "Internal error: polygon not closed\n");
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}
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}
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for (size_t n = i; n < j - 1; n++) {
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out.push_back(geom[n]);
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}
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out.push_back(draw(VT_CLOSEPATH, 0, 0));
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i = j - 1;
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}
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}
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return out;
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}
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// @@@
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// @@@
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drawvec simple_clip_poly(drawvec &geom, long long minx, long long miny, long long maxx, long long maxy) {
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drawvec out;
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mapbox::geometry::point<long long> min(minx, miny);
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mapbox::geometry::point<long long> max(maxx, maxy);
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mapbox::geometry::box<long long> bbox(min, max);
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for (size_t i = 0; i < geom.size(); i++) {
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if (geom[i].op == VT_MOVETO) {
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size_t j;
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for (j = i + 1; j < geom.size(); j++) {
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if (geom[j].op != VT_LINETO) {
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break;
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}
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}
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mapbox::geometry::linear_ring<long long> ring;
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for (size_t k = i; k < j; k++) {
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ring.push_back(mapbox::geometry::point<long long>(geom[k].x, geom[k].y));
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}
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mapbox::geometry::linear_ring<long long> lr = mapbox::geometry::wagyu::quick_clip::quick_lr_clip(ring, bbox);
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if (lr.size() > 0) {
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for (size_t k = 0; k < lr.size(); k++) {
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if (k == 0) {
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out.push_back(draw(VT_MOVETO, lr[k].x, lr[k].y));
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} else {
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out.push_back(draw(VT_LINETO, lr[k].x, lr[k].y));
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}
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}
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if (lr.size() > 0 && lr[0] != lr[lr.size() - 1]) {
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out.push_back(draw(VT_LINETO, lr[0].x, lr[0].y));
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}
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}
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i = j - 1;
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} else {
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fprintf(stderr, "Unexpected operation in polygon %d\n", (int) geom[i].op);
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exit(EXIT_IMPOSSIBLE);
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}
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}
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return out;
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}
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drawvec simple_clip_poly(drawvec &geom, int z, int buffer) {
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long long area = 1LL << (32 - z);
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long long clip_buffer = buffer * area / 256;
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return simple_clip_poly(geom, -clip_buffer, -clip_buffer, area + clip_buffer, area + clip_buffer);
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}
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// @@@
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drawvec reduce_tiny_poly(drawvec &geom, int z, int detail, bool *still_needs_simplification, bool *reduced_away, double *accum_area, serial_feature *this_feature, serial_feature *tiny_feature) {
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drawvec out;
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const double pixel = (1LL << (32 - detail - z)) * (double) tiny_polygon_size;
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@@ -306,6 +732,30 @@ drawvec reduce_tiny_poly(drawvec &geom, int z, int detail, bool *still_needs_sim
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return out;
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}
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// @@@
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drawvec clip_point(drawvec &geom, int z, long long buffer) {
|
||||
long long min = 0;
|
||||
long long area = 1LL << (32 - z);
|
||||
|
||||
min -= buffer * area / 256;
|
||||
area += buffer * area / 256;
|
||||
|
||||
return clip_point(geom, min, min, area, area);
|
||||
}
|
||||
|
||||
drawvec clip_point(drawvec &geom, long long minx, long long miny, long long maxx, long long maxy) {
|
||||
drawvec out;
|
||||
|
||||
for (size_t i = 0; i < geom.size(); i++) {
|
||||
if (geom[i].x >= minx && geom[i].y >= miny && geom[i].x <= maxx && geom[i].y <= maxy) {
|
||||
out.push_back(geom[i]);
|
||||
}
|
||||
}
|
||||
|
||||
return out;
|
||||
}
|
||||
// @@@
|
||||
|
||||
int quick_check(long long *bbox, int z, long long buffer) {
|
||||
long long min = 0;
|
||||
long long area = 1LL << (32 - z);
|
||||
@@ -339,6 +789,47 @@ bool point_within_tile(long long x, long long y, int z) {
|
||||
return x >= 0 && y >= 0 && x < area && y < area;
|
||||
}
|
||||
|
||||
// @@@
|
||||
drawvec clip_lines(drawvec &geom, int z, long long buffer) {
|
||||
long long min = 0;
|
||||
long long area = 1LL << (32 - z);
|
||||
min -= buffer * area / 256;
|
||||
area += buffer * area / 256;
|
||||
|
||||
return clip_lines(geom, min, min, area, area);
|
||||
}
|
||||
|
||||
drawvec clip_lines(drawvec &geom, long long minx, long long miny, long long maxx, long long maxy) {
|
||||
drawvec out;
|
||||
|
||||
for (size_t i = 0; i < geom.size(); i++) {
|
||||
if (i > 0 && (geom[i - 1].op == VT_MOVETO || geom[i - 1].op == VT_LINETO) && geom[i].op == VT_LINETO) {
|
||||
double x1 = geom[i - 1].x;
|
||||
double y1 = geom[i - 1].y;
|
||||
|
||||
double x2 = geom[i - 0].x;
|
||||
double y2 = geom[i - 0].y;
|
||||
|
||||
int c = clip(&x1, &y1, &x2, &y2, minx, miny, maxx, maxy);
|
||||
|
||||
if (c > 1) { // clipped
|
||||
out.push_back(draw(VT_MOVETO, x1, y1));
|
||||
out.push_back(draw(VT_LINETO, x2, y2));
|
||||
out.push_back(draw(VT_MOVETO, geom[i].x, geom[i].y));
|
||||
} else if (c == 1) { // unchanged
|
||||
out.push_back(geom[i]);
|
||||
} else { // clipped away entirely
|
||||
out.push_back(draw(VT_MOVETO, geom[i].x, geom[i].y));
|
||||
}
|
||||
} else {
|
||||
out.push_back(geom[i]);
|
||||
}
|
||||
}
|
||||
|
||||
return out;
|
||||
}
|
||||
// @@@
|
||||
|
||||
static double square_distance_from_line(long long point_x, long long point_y, long long segA_x, long long segA_y, long long segB_x, long long segB_y) {
|
||||
long long p2x = segB_x - segA_x;
|
||||
long long p2y = segB_y - segA_y;
|
||||
@@ -774,6 +1265,91 @@ std::vector<drawvec> chop_polygon(std::vector<drawvec> &geoms) {
|
||||
}
|
||||
}
|
||||
|
||||
// @@@
|
||||
#define INSIDE 0
|
||||
#define LEFT 1
|
||||
#define RIGHT 2
|
||||
#define BOTTOM 4
|
||||
#define TOP 8
|
||||
|
||||
static int computeOutCode(double x, double y, double xmin, double ymin, double xmax, double ymax) {
|
||||
int code = INSIDE;
|
||||
|
||||
if (x < xmin) {
|
||||
code |= LEFT;
|
||||
} else if (x > xmax) {
|
||||
code |= RIGHT;
|
||||
}
|
||||
|
||||
if (y < ymin) {
|
||||
code |= BOTTOM;
|
||||
} else if (y > ymax) {
|
||||
code |= TOP;
|
||||
}
|
||||
|
||||
return code;
|
||||
}
|
||||
|
||||
int clip(double *x0, double *y0, double *x1, double *y1, double xmin, double ymin, double xmax, double ymax) {
|
||||
int outcode0 = computeOutCode(*x0, *y0, xmin, ymin, xmax, ymax);
|
||||
int outcode1 = computeOutCode(*x1, *y1, xmin, ymin, xmax, ymax);
|
||||
int accept = 0;
|
||||
int changed = 0;
|
||||
|
||||
while (1) {
|
||||
if (!(outcode0 | outcode1)) { // Bitwise OR is 0. Trivially accept and get out of loop
|
||||
accept = 1;
|
||||
break;
|
||||
} else if (outcode0 & outcode1) { // Bitwise AND is not 0. Trivially reject and get out of loop
|
||||
break;
|
||||
} else {
|
||||
// failed both tests, so calculate the line segment to clip
|
||||
// from an outside point to an intersection with clip edge
|
||||
double x = *x0, y = *y0;
|
||||
|
||||
// At least one endpoint is outside the clip rectangle; pick it.
|
||||
int outcodeOut = outcode0 ? outcode0 : outcode1;
|
||||
|
||||
// Now find the intersection point;
|
||||
// use formulas y = y0 + slope * (x - x0), x = x0 + (1 / slope) * (y - y0)
|
||||
if (outcodeOut & TOP) { // point is above the clip rectangle
|
||||
x = *x0 + (*x1 - *x0) * (ymax - *y0) / (*y1 - *y0);
|
||||
y = ymax;
|
||||
} else if (outcodeOut & BOTTOM) { // point is below the clip rectangle
|
||||
x = *x0 + (*x1 - *x0) * (ymin - *y0) / (*y1 - *y0);
|
||||
y = ymin;
|
||||
} else if (outcodeOut & RIGHT) { // point is to the right of clip rectangle
|
||||
y = *y0 + (*y1 - *y0) * (xmax - *x0) / (*x1 - *x0);
|
||||
x = xmax;
|
||||
} else if (outcodeOut & LEFT) { // point is to the left of clip rectangle
|
||||
y = *y0 + (*y1 - *y0) * (xmin - *x0) / (*x1 - *x0);
|
||||
x = xmin;
|
||||
}
|
||||
|
||||
// Now we move outside point to intersection point to clip
|
||||
// and get ready for next pass.
|
||||
if (outcodeOut == outcode0) {
|
||||
*x0 = x;
|
||||
*y0 = y;
|
||||
outcode0 = computeOutCode(*x0, *y0, xmin, ymin, xmax, ymax);
|
||||
changed = 1;
|
||||
} else {
|
||||
*x1 = x;
|
||||
*y1 = y;
|
||||
outcode1 = computeOutCode(*x1, *y1, xmin, ymin, xmax, ymax);
|
||||
changed = 1;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (accept == 0) {
|
||||
return 0;
|
||||
} else {
|
||||
return changed + 1;
|
||||
}
|
||||
}
|
||||
// @@@
|
||||
|
||||
drawvec stairstep(drawvec &geom, int z, int detail) {
|
||||
drawvec out;
|
||||
double scale = 1 << (32 - detail - z);
|
||||
|
||||
Reference in New Issue
Block a user