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godot/core/math/geometry.h
Marcel Admiraal 3cbc6330bb Fix Geometry::get_closest_points_between_segments() returns NaN 
Also fix Geometry::get_closest_distance_between_segments() returning
incorrect values.
2022-09-01 17:51:33 +01:00

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/*************************************************************************/
/* geometry.h */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
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/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md). */
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#ifndef GEOMETRY_H
#define GEOMETRY_H
#include "core/math/delaunay.h"
#include "core/math/face3.h"
#include "core/math/rect2.h"
#include "core/math/triangulate.h"
#include "core/math/vector3.h"
#include "core/object.h"
#include "core/pool_vector.h"
#include "core/print_string.h"
#include "core/vector.h"
class Geometry {
public:
static real_t get_closest_points_between_segments(const Vector2 &p1, const Vector2 &q1, const Vector2 &p2, const Vector2 &q2, Vector2 &c1, Vector2 &c2) {
Vector2 d1 = q1 - p1; // Direction vector of segment S1.
Vector2 d2 = q2 - p2; // Direction vector of segment S2.
Vector2 r = p1 - p2;
real_t a = d1.dot(d1); // Squared length of segment S1, always nonnegative.
real_t e = d2.dot(d2); // Squared length of segment S2, always nonnegative.
real_t f = d2.dot(r);
real_t s, t;
// Check if either or both segments degenerate into points.
if (a <= (real_t)CMP_EPSILON && e <= (real_t)CMP_EPSILON) {
// Both segments degenerate into points.
c1 = p1;
c2 = p2;
return Math::sqrt((c1 - c2).dot(c1 - c2));
}
if (a <= (real_t)CMP_EPSILON) {
// First segment degenerates into a point.
s = 0;
t = f / e; // s = 0 => t = (b*s + f) / e = f / e
t = CLAMP(t, 0, 1);
} else {
real_t c = d1.dot(r);
if (e <= (real_t)CMP_EPSILON) {
// Second segment degenerates into a point.
t = 0;
s = CLAMP(-c / a, 0, 1); // t = 0 => s = (b*t - c) / a = -c / a
} else {
// The general nondegenerate case starts here.
real_t b = d1.dot(d2);
real_t denom = a * e - b * b; // Always nonnegative.
// If segments not parallel, compute closest point on L1 to L2 and
// clamp to segment S1. Else pick arbitrary s (here 0).
if (denom != 0) {
s = CLAMP((b * f - c * e) / denom, 0, 1);
} else {
s = 0;
}
// Compute point on L2 closest to S1(s) using
// t = Dot((P1 + D1*s) - P2,D2) / Dot(D2,D2) = (b*s + f) / e
t = (b * s + f) / e;
//If t in [0,1] done. Else clamp t, recompute s for the new value
// of t using s = Dot((P2 + D2*t) - P1,D1) / Dot(D1,D1)= (t*b - c) / a
// and clamp s to [0, 1].
if (t < 0) {
t = 0;
s = CLAMP(-c / a, 0, 1);
} else if (t > 1) {
t = 1;
s = CLAMP((b - c) / a, 0, 1);
}
}
}
c1 = p1 + d1 * s;
c2 = p2 + d2 * t;
return Math::sqrt((c1 - c2).dot(c1 - c2));
}
static void get_closest_points_between_segments(const Vector3 &p_p0, const Vector3 &p_p1, const Vector3 &p_q0, const Vector3 &p_q1, Vector3 &r_ps, Vector3 &r_qt);
static real_t get_closest_distance_between_segments(const Vector3 &p_p0, const Vector3 &p_p1, const Vector3 &p_q0, const Vector3 &p_q1);
static inline bool ray_intersects_triangle(const Vector3 &p_from, const Vector3 &p_dir, const Vector3 &p_v0, const Vector3 &p_v1, const Vector3 &p_v2, Vector3 *r_res = nullptr) {
Vector3 e1 = p_v1 - p_v0;
Vector3 e2 = p_v2 - p_v0;
Vector3 h = p_dir.cross(e2);
real_t a = e1.dot(h);
if (Math::is_zero_approx(a)) { // Parallel test.
return false;
}
real_t f = 1 / a;
Vector3 s = p_from - p_v0;
real_t u = f * s.dot(h);
if ((u < 0) || (u > 1)) {
return false;
}
Vector3 q = s.cross(e1);
real_t v = f * p_dir.dot(q);
if ((v < 0) || (u + v > 1)) {
return false;
}
// At this stage we can compute t to find out where
// the intersection point is on the line.
real_t t = f * e2.dot(q);
if (t > 0.00001f) { // ray intersection
if (r_res) {
*r_res = p_from + p_dir * t;
}
return true;
} else { // This means that there is a line intersection but not a ray intersection.
return false;
}
}
static inline bool segment_intersects_triangle(const Vector3 &p_from, const Vector3 &p_to, const Vector3 &p_v0, const Vector3 &p_v1, const Vector3 &p_v2, Vector3 *r_res = nullptr) {
Vector3 rel = p_to - p_from;
Vector3 e1 = p_v1 - p_v0;
Vector3 e2 = p_v2 - p_v0;
Vector3 h = rel.cross(e2);
real_t a = e1.dot(h);
if (Math::is_zero_approx(a)) { // Parallel test.
return false;
}
real_t f = 1 / a;
Vector3 s = p_from - p_v0;
real_t u = f * s.dot(h);
if ((u < 0) || (u > 1)) {
return false;
}
Vector3 q = s.cross(e1);
real_t v = f * rel.dot(q);
if ((v < 0) || (u + v > 1)) {
return false;
}
// At this stage we can compute t to find out where
// the intersection point is on the line.
real_t t = f * e2.dot(q);
if (t > (real_t)CMP_EPSILON && t <= 1) { // Ray intersection.
if (r_res) {
*r_res = p_from + rel * t;
}
return true;
} else { // This means that there is a line intersection but not a ray intersection.
return false;
}
}
static inline bool segment_intersects_sphere(const Vector3 &p_from, const Vector3 &p_to, const Vector3 &p_sphere_pos, real_t p_sphere_radius, Vector3 *r_res = nullptr, Vector3 *r_norm = nullptr) {
Vector3 sphere_pos = p_sphere_pos - p_from;
Vector3 rel = (p_to - p_from);
real_t rel_l = rel.length();
if (rel_l < (real_t)CMP_EPSILON) {
return false; // Both points are the same.
}
Vector3 normal = rel / rel_l;
real_t sphere_d = normal.dot(sphere_pos);
real_t ray_distance = sphere_pos.distance_to(normal * sphere_d);
if (ray_distance >= p_sphere_radius) {
return false;
}
real_t inters_d2 = p_sphere_radius * p_sphere_radius - ray_distance * ray_distance;
real_t inters_d = sphere_d;
if (inters_d2 >= (real_t)CMP_EPSILON) {
inters_d -= Math::sqrt(inters_d2);
}
// Check in segment.
if (inters_d < 0 || inters_d > rel_l) {
return false;
}
Vector3 result = p_from + normal * inters_d;
if (r_res) {
*r_res = result;
}
if (r_norm) {
*r_norm = (result - p_sphere_pos).normalized();
}
return true;
}
static inline bool segment_intersects_cylinder(const Vector3 &p_from, const Vector3 &p_to, real_t p_height, real_t p_radius, Vector3 *r_res = nullptr, Vector3 *r_norm = nullptr, int p_cylinder_axis = 2) {
Vector3 rel = (p_to - p_from);
real_t rel_l = rel.length();
if (rel_l < (real_t)CMP_EPSILON) {
return false; // Both points are the same.
}
ERR_FAIL_COND_V(p_cylinder_axis < 0, false);
ERR_FAIL_COND_V(p_cylinder_axis > 2, false);
Vector3 cylinder_axis;
cylinder_axis[p_cylinder_axis] = 1;
// First check if they are parallel.
Vector3 normal = (rel / rel_l);
Vector3 crs = normal.cross(cylinder_axis);
real_t crs_l = crs.length();
Vector3 axis_dir;
if (crs_l < (real_t)CMP_EPSILON) {
Vector3 side_axis;
side_axis[(p_cylinder_axis + 1) % 3] = 1; // Any side axis OK.
axis_dir = side_axis;
} else {
axis_dir = crs / crs_l;
}
real_t dist = axis_dir.dot(p_from);
if (dist >= p_radius) {
return false; // Too far away.
}
// Convert to 2D.
real_t w2 = p_radius * p_radius - dist * dist;
if (w2 < (real_t)CMP_EPSILON) {
return false; // Avoid numerical error.
}
Size2 size(Math::sqrt(w2), p_height * 0.5f);
Vector3 side_dir = axis_dir.cross(cylinder_axis).normalized();
Vector2 from2D(side_dir.dot(p_from), p_from[p_cylinder_axis]);
Vector2 to2D(side_dir.dot(p_to), p_to[p_cylinder_axis]);
real_t min = 0, max = 1;
int axis = -1;
for (int i = 0; i < 2; i++) {
real_t seg_from = from2D[i];
real_t seg_to = to2D[i];
real_t box_begin = -size[i];
real_t box_end = size[i];
real_t cmin, cmax;
if (seg_from < seg_to) {
if (seg_from > box_end || seg_to < box_begin) {
return false;
}
real_t length = seg_to - seg_from;
cmin = (seg_from < box_begin) ? ((box_begin - seg_from) / length) : 0;
cmax = (seg_to > box_end) ? ((box_end - seg_from) / length) : 1;
} else {
if (seg_to > box_end || seg_from < box_begin) {
return false;
}
real_t length = seg_to - seg_from;
cmin = (seg_from > box_end) ? (box_end - seg_from) / length : 0;
cmax = (seg_to < box_begin) ? (box_begin - seg_from) / length : 1;
}
if (cmin > min) {
min = cmin;
axis = i;
}
if (cmax < max) {
max = cmax;
}
if (max < min) {
return false;
}
}
// Convert to 3D again.
Vector3 result = p_from + (rel * min);
Vector3 res_normal = result;
if (axis == 0) {
res_normal[p_cylinder_axis] = 0;
} else {
int axis_side = (p_cylinder_axis + 1) % 3;
res_normal[axis_side] = 0;
axis_side = (axis_side + 1) % 3;
res_normal[axis_side] = 0;
}
res_normal.normalize();
if (r_res) {
*r_res = result;
}
if (r_norm) {
*r_norm = res_normal;
}
return true;
}
static bool segment_intersects_convex(const Vector3 &p_from, const Vector3 &p_to, const Plane *p_planes, int p_plane_count, Vector3 *p_res, Vector3 *p_norm) {
real_t min = -1e20, max = 1e20;
Vector3 rel = p_to - p_from;
real_t rel_l = rel.length();
if (rel_l < (real_t)CMP_EPSILON) {
return false;
}
Vector3 dir = rel / rel_l;
int min_index = -1;
for (int i = 0; i < p_plane_count; i++) {
const Plane &p = p_planes[i];
real_t den = p.normal.dot(dir);
if (Math::abs(den) <= (real_t)CMP_EPSILON) {
continue; // Ignore parallel plane.
}
real_t dist = -p.distance_to(p_from) / den;
if (den > 0) {
// Backwards facing plane.
if (dist < max) {
max = dist;
}
} else {
// Front facing plane.
if (dist > min) {
min = dist;
min_index = i;
}
}
}
if (max <= min || min < 0 || min > rel_l || min_index == -1) { // Exit conditions.
return false; // No intersection.
}
if (p_res) {
*p_res = p_from + dir * min;
}
if (p_norm) {
*p_norm = p_planes[min_index].normal;
}
return true;
}
static Vector3 get_closest_point_to_segment(const Vector3 &p_point, const Vector3 *p_segment) {
Vector3 p = p_point - p_segment[0];
Vector3 n = p_segment[1] - p_segment[0];
real_t l2 = n.length_squared();
if (l2 < 1e-20f) {
return p_segment[0]; // Both points are the same, just give any.
}
real_t d = n.dot(p) / l2;
if (d <= 0) {
return p_segment[0]; // Before first point.
} else if (d >= 1.0) {
return p_segment[1]; // After first point.
} else {
return p_segment[0] + n * d; // Inside.
}
}
static Vector3 get_closest_point_to_segment_uncapped(const Vector3 &p_point, const Vector3 *p_segment) {
Vector3 p = p_point - p_segment[0];
Vector3 n = p_segment[1] - p_segment[0];
real_t l2 = n.length_squared();
if (l2 < 1e-20f) {
return p_segment[0]; // Both points are the same, just give any.
}
real_t d = n.dot(p) / l2;
return p_segment[0] + n * d; // Inside.
}
static Vector2 get_closest_point_to_segment_2d(const Vector2 &p_point, const Vector2 *p_segment) {
Vector2 p = p_point - p_segment[0];
Vector2 n = p_segment[1] - p_segment[0];
real_t l2 = n.length_squared();
if (l2 < 1e-20f) {
return p_segment[0]; // Both points are the same, just give any.
}
real_t d = n.dot(p) / l2;
if (d <= 0) {
return p_segment[0]; // Before first point.
} else if (d >= 1) {
return p_segment[1]; // After first point.
} else {
return p_segment[0] + n * d; // Inside.
}
}
static bool is_point_in_triangle(const Vector2 &s, const Vector2 &a, const Vector2 &b, const Vector2 &c) {
Vector2 an = a - s;
Vector2 bn = b - s;
Vector2 cn = c - s;
bool orientation = an.cross(bn) > 0;
if ((bn.cross(cn) > 0) != orientation) {
return false;
}
return (cn.cross(an) > 0) == orientation;
}
static Vector3 barycentric_coordinates_2d(const Vector2 &s, const Vector2 &a, const Vector2 &b, const Vector2 &c) {
// http://www.blackpawn.com/texts/pointinpoly/
Vector2 v0 = c - a;
Vector2 v1 = b - a;
Vector2 v2 = s - a;
// Compute dot products
double dot00 = v0.dot(v0);
double dot01 = v0.dot(v1);
double dot02 = v0.dot(v2);
double dot11 = v1.dot(v1);
double dot12 = v1.dot(v2);
// Check for divide by zero
double denom = dot00 * dot11 - dot01 * dot01;
if (denom == 0.0) {
return Vector3(0.0, 0.0, 0.0);
}
// Compute barycentric coordinates
double invDenom = 1.0 / denom;
double b2 = (dot11 * dot02 - dot01 * dot12) * invDenom;
double b1 = (dot00 * dot12 - dot01 * dot02) * invDenom;
double b0 = 1.0 - b2 - b1;
return Vector3(b0, b1, b2);
}
static Vector2 get_closest_point_to_segment_uncapped_2d(const Vector2 &p_point, const Vector2 *p_segment) {
Vector2 p = p_point - p_segment[0];
Vector2 n = p_segment[1] - p_segment[0];
real_t l2 = n.length_squared();
if (l2 < 1e-20f) {
return p_segment[0]; // Both points are the same, just give any.
}
real_t d = n.dot(p) / l2;
return p_segment[0] + n * d; // Inside.
}
static bool line_intersects_line_2d(const Vector2 &p_from_a, const Vector2 &p_dir_a, const Vector2 &p_from_b, const Vector2 &p_dir_b, Vector2 &r_result) {
// See http://paulbourke.net/geometry/pointlineplane/
const real_t denom = p_dir_b.y * p_dir_a.x - p_dir_b.x * p_dir_a.y;
if (Math::is_zero_approx(denom)) { // Parallel?
return false;
}
const Vector2 v = p_from_a - p_from_b;
const real_t t = (p_dir_b.x * v.y - p_dir_b.y * v.x) / denom;
r_result = p_from_a + t * p_dir_a;
return true;
}
static bool segment_intersects_segment_2d(const Vector2 &p_from_a, const Vector2 &p_to_a, const Vector2 &p_from_b, const Vector2 &p_to_b, Vector2 *r_result) {
Vector2 B = p_to_a - p_from_a;
Vector2 C = p_from_b - p_from_a;
Vector2 D = p_to_b - p_from_a;
real_t ABlen = B.dot(B);
if (ABlen <= 0) {
return false;
}
Vector2 Bn = B / ABlen;
C = Vector2(C.x * Bn.x + C.y * Bn.y, C.y * Bn.x - C.x * Bn.y);
D = Vector2(D.x * Bn.x + D.y * Bn.y, D.y * Bn.x - D.x * Bn.y);
if ((C.y < 0 && D.y < 0) || (C.y >= 0 && D.y >= 0)) {
return false;
}
real_t ABpos = D.x + (C.x - D.x) * D.y / (D.y - C.y);
// Fail if segment C-D crosses line A-B outside of segment A-B.
if ((ABpos < 0) || (ABpos > 1)) {
return false;
}
// (4) Apply the discovered position to line A-B in the original coordinate system.
if (r_result) {
*r_result = p_from_a + B * ABpos;
}
return true;
}
static inline bool point_in_projected_triangle(const Vector3 &p_point, const Vector3 &p_v1, const Vector3 &p_v2, const Vector3 &p_v3) {
Vector3 face_n = (p_v1 - p_v3).cross(p_v1 - p_v2);
Vector3 n1 = (p_point - p_v3).cross(p_point - p_v2);
if (face_n.dot(n1) < 0) {
return false;
}
Vector3 n2 = (p_v1 - p_v3).cross(p_v1 - p_point);
if (face_n.dot(n2) < 0) {
return false;
}
Vector3 n3 = (p_v1 - p_point).cross(p_v1 - p_v2);
if (face_n.dot(n3) < 0) {
return false;
}
return true;
}
static inline bool triangle_sphere_intersection_test(const Vector3 *p_triangle, const Vector3 &p_normal, const Vector3 &p_sphere_pos, real_t p_sphere_radius, Vector3 &r_triangle_contact, Vector3 &r_sphere_contact) {
real_t d = p_normal.dot(p_sphere_pos) - p_normal.dot(p_triangle[0]);
if (d > p_sphere_radius || d < -p_sphere_radius) { // Not touching the plane of the face, return.
return false;
}
Vector3 contact = p_sphere_pos - (p_normal * d);
/** 2nd) TEST INSIDE TRIANGLE **/
if (Geometry::point_in_projected_triangle(contact, p_triangle[0], p_triangle[1], p_triangle[2])) {
r_triangle_contact = contact;
r_sphere_contact = p_sphere_pos - p_normal * p_sphere_radius;
//printf("solved inside triangle\n");
return true;
}
/** 3rd TEST INSIDE EDGE CYLINDERS **/
const Vector3 verts[4] = { p_triangle[0], p_triangle[1], p_triangle[2], p_triangle[0] }; // for() friendly
for (int i = 0; i < 3; i++) {
// Check edge cylinder.
Vector3 n1 = verts[i] - verts[i + 1];
Vector3 n2 = p_sphere_pos - verts[i + 1];
///@TODO Maybe discard by range here to make the algorithm quicker.
// Check point within cylinder radius.
Vector3 axis = n1.cross(n2).cross(n1);
axis.normalize();
real_t ad = axis.dot(n2);
if (ABS(ad) > p_sphere_radius) {
// No chance with this edge, too far away.
continue;
}
// Check point within edge capsule cylinder.
/** 4th TEST INSIDE EDGE POINTS **/
real_t sphere_at = n1.dot(n2);
if (sphere_at >= 0 && sphere_at < n1.dot(n1)) {
r_triangle_contact = p_sphere_pos - axis * (axis.dot(n2));
r_sphere_contact = p_sphere_pos - axis * p_sphere_radius;
// Point inside here.
return true;
}
real_t r2 = p_sphere_radius * p_sphere_radius;
if (n2.length_squared() < r2) {
Vector3 n = (p_sphere_pos - verts[i + 1]).normalized();
r_triangle_contact = verts[i + 1];
r_sphere_contact = p_sphere_pos - n * p_sphere_radius;
return true;
}
if (n2.distance_squared_to(n1) < r2) {
Vector3 n = (p_sphere_pos - verts[i]).normalized();
r_triangle_contact = verts[i];
r_sphere_contact = p_sphere_pos - n * p_sphere_radius;
return true;
}
break; // It's pointless to continue at this point, so save some CPU cycles.
}
return false;
}
static inline bool is_point_in_circle(const Vector2 &p_point, const Vector2 &p_circle_pos, real_t p_circle_radius) {
return p_point.distance_squared_to(p_circle_pos) <= p_circle_radius * p_circle_radius;
}
static real_t segment_intersects_circle(const Vector2 &p_from, const Vector2 &p_to, const Vector2 &p_circle_pos, real_t p_circle_radius) {
Vector2 line_vec = p_to - p_from;
Vector2 vec_to_line = p_from - p_circle_pos;
// Create a quadratic formula of the form ax^2 + bx + c = 0
real_t a, b, c;
a = line_vec.dot(line_vec);
b = 2 * vec_to_line.dot(line_vec);
c = vec_to_line.dot(vec_to_line) - p_circle_radius * p_circle_radius;
// Solve for t.
real_t sqrtterm = b * b - 4 * a * c;
// If the term we intend to square root is less than 0 then the answer won't be real,
// so it definitely won't be t in the range 0 to 1.
if (sqrtterm < 0) {
return -1;
}
// If we can assume that the line segment starts outside the circle (e.g. for continuous time collision detection)
// then the following can be skipped and we can just return the equivalent of res1.
sqrtterm = Math::sqrt(sqrtterm);
real_t res1 = (-b - sqrtterm) / (2 * a);
real_t res2 = (-b + sqrtterm) / (2 * a);
if (res1 >= 0 && res1 <= 1) {
return res1;
}
if (res2 >= 0 && res2 <= 1) {
return res2;
}
return -1;
}
static inline Vector<Vector3> clip_polygon(const Vector<Vector3> &polygon, const Plane &p_plane) {
enum LocationCache {
LOC_INSIDE = 1,
LOC_BOUNDARY = 0,
LOC_OUTSIDE = -1
};
if (polygon.size() == 0) {
return polygon;
}
int *location_cache = (int *)alloca(sizeof(int) * polygon.size());
int inside_count = 0;
int outside_count = 0;
for (int a = 0; a < polygon.size(); a++) {
real_t dist = p_plane.distance_to(polygon[a]);
if (dist < (real_t)-CMP_POINT_IN_PLANE_EPSILON) {
location_cache[a] = LOC_INSIDE;
inside_count++;
} else {
if (dist > (real_t)CMP_POINT_IN_PLANE_EPSILON) {
location_cache[a] = LOC_OUTSIDE;
outside_count++;
} else {
location_cache[a] = LOC_BOUNDARY;
}
}
}
if (outside_count == 0) {
return polygon; // No changes.
} else if (inside_count == 0) {
return Vector<Vector3>(); // Empty.
}
long previous = polygon.size() - 1;
Vector<Vector3> clipped;
for (int index = 0; index < polygon.size(); index++) {
int loc = location_cache[index];
if (loc == LOC_OUTSIDE) {
if (location_cache[previous] == LOC_INSIDE) {
const Vector3 &v1 = polygon[previous];
const Vector3 &v2 = polygon[index];
Vector3 segment = v1 - v2;
real_t den = p_plane.normal.dot(segment);
real_t dist = p_plane.distance_to(v1) / den;
dist = -dist;
clipped.push_back(v1 + segment * dist);
}
} else {
const Vector3 &v1 = polygon[index];
if ((loc == LOC_INSIDE) && (location_cache[previous] == LOC_OUTSIDE)) {
const Vector3 &v2 = polygon[previous];
Vector3 segment = v1 - v2;
real_t den = p_plane.normal.dot(segment);
real_t dist = p_plane.distance_to(v1) / den;
dist = -dist;
clipped.push_back(v1 + segment * dist);
}
clipped.push_back(v1);
}
previous = index;
}
return clipped;
}
enum PolyBooleanOperation {
OPERATION_UNION,
OPERATION_DIFFERENCE,
OPERATION_INTERSECTION,
OPERATION_XOR
};
enum PolyJoinType {
JOIN_SQUARE,
JOIN_ROUND,
JOIN_MITER
};
enum PolyEndType {
END_POLYGON,
END_JOINED,
END_BUTT,
END_SQUARE,
END_ROUND
};
static Vector<Vector<Point2>> merge_polygons_2d(const Vector<Point2> &p_polygon_a, const Vector<Point2> &p_polygon_b) {
return _polypaths_do_operation(OPERATION_UNION, p_polygon_a, p_polygon_b);
}
static Vector<Vector<Point2>> clip_polygons_2d(const Vector<Point2> &p_polygon_a, const Vector<Point2> &p_polygon_b) {
return _polypaths_do_operation(OPERATION_DIFFERENCE, p_polygon_a, p_polygon_b);
}
static Vector<Vector<Point2>> intersect_polygons_2d(const Vector<Point2> &p_polygon_a, const Vector<Point2> &p_polygon_b) {
return _polypaths_do_operation(OPERATION_INTERSECTION, p_polygon_a, p_polygon_b);
}
static Vector<Vector<Point2>> exclude_polygons_2d(const Vector<Point2> &p_polygon_a, const Vector<Point2> &p_polygon_b) {
return _polypaths_do_operation(OPERATION_XOR, p_polygon_a, p_polygon_b);
}
static Vector<Vector<Point2>> clip_polyline_with_polygon_2d(const Vector<Vector2> &p_polyline, const Vector<Vector2> &p_polygon) {
return _polypaths_do_operation(OPERATION_DIFFERENCE, p_polyline, p_polygon, true);
}
static Vector<Vector<Point2>> intersect_polyline_with_polygon_2d(const Vector<Vector2> &p_polyline, const Vector<Vector2> &p_polygon) {
return _polypaths_do_operation(OPERATION_INTERSECTION, p_polyline, p_polygon, true);
}
static Vector<Vector<Point2>> offset_polygon_2d(const Vector<Vector2> &p_polygon, real_t p_delta, PolyJoinType p_join_type) {
return _polypath_offset(p_polygon, p_delta, p_join_type, END_POLYGON);
}
static Vector<Vector<Point2>> offset_polyline_2d(const Vector<Vector2> &p_polygon, real_t p_delta, PolyJoinType p_join_type, PolyEndType p_end_type) {
ERR_FAIL_COND_V_MSG(p_end_type == END_POLYGON, Vector<Vector<Point2>>(), "Attempt to offset a polyline like a polygon (use offset_polygon_2d instead).");
return _polypath_offset(p_polygon, p_delta, p_join_type, p_end_type);
}
static Vector<int> triangulate_delaunay_2d(const Vector<Vector2> &p_points) {
Vector<Delaunay2D::Triangle> tr = Delaunay2D::triangulate(p_points);
Vector<int> triangles;
for (int i = 0; i < tr.size(); i++) {
triangles.push_back(tr[i].points[0]);
triangles.push_back(tr[i].points[1]);
triangles.push_back(tr[i].points[2]);
}
return triangles;
}
static Vector<int> triangulate_polygon(const Vector<Vector2> &p_polygon) {
Vector<int> triangles;
if (!Triangulate::triangulate(p_polygon, triangles)) {
return Vector<int>(); //fail
}
return triangles;
}
static bool is_polygon_clockwise(const Vector<Vector2> &p_polygon) {
int c = p_polygon.size();
if (c < 3) {
return false;
}
const Vector2 *p = p_polygon.ptr();
real_t sum = 0;
for (int i = 0; i < c; i++) {
const Vector2 &v1 = p[i];
const Vector2 &v2 = p[(i + 1) % c];
sum += (v2.x - v1.x) * (v2.y + v1.y);
}
return sum > 0.0f;
}
// Alternate implementation that should be faster.
static bool is_point_in_polygon(const Vector2 &p_point, const Vector<Vector2> &p_polygon) {
int c = p_polygon.size();
if (c < 3) {
return false;
}
const Vector2 *p = p_polygon.ptr();
Vector2 further_away(-1e20, -1e20);
Vector2 further_away_opposite(1e20, 1e20);
for (int i = 0; i < c; i++) {
further_away.x = MAX(p[i].x, further_away.x);
further_away.y = MAX(p[i].y, further_away.y);
further_away_opposite.x = MIN(p[i].x, further_away_opposite.x);
further_away_opposite.y = MIN(p[i].y, further_away_opposite.y);
}
// Make point outside that won't intersect with points in segment from p_point.
further_away += (further_away - further_away_opposite) * Vector2(1.221313, 1.512312);
int intersections = 0;
for (int i = 0; i < c; i++) {
const Vector2 &v1 = p[i];
const Vector2 &v2 = p[(i + 1) % c];
if (segment_intersects_segment_2d(v1, v2, p_point, further_away, nullptr)) {
intersections++;
}
}
return (intersections & 1);
}
static PoolVector<PoolVector<Face3>> separate_objects(PoolVector<Face3> p_array);
// Create a "wrap" that encloses the given geometry.
static PoolVector<Face3> wrap_geometry(PoolVector<Face3> p_array, real_t *p_error = nullptr);
struct MeshData {
struct Face {
Plane plane;
Vector<int> indices;
};
Vector<Face> faces;
struct Edge {
int a, b;
};
Vector<Edge> edges;
Vector<Vector3> vertices;
void optimize_vertices();
void clear();
};
// Occluder Meshes contain convex faces which may contain 0 to many convex holes.
// (holes are analogous to portals)
struct OccluderMeshData {
struct Hole {
LocalVectori<uint32_t> indices;
};
struct Face {
Plane plane;
bool two_way = false;
LocalVectori<uint32_t> indices;
LocalVectori<Hole> holes;
};
LocalVectori<Face> faces;
LocalVectori<Vector3> vertices;
void clear();
};
_FORCE_INLINE_ static int get_uv84_normal_bit(const Vector3 &p_vector) {
int lat = Math::fast_ftoi(Math::floor(Math::acos(p_vector.dot(Vector3(0, 1, 0))) * 4.0 / Math_PI + 0.5));
if (lat == 0) {
return 24;
} else if (lat == 4) {
return 25;
}
int lon = Math::fast_ftoi(Math::floor((Math_PI + Math::atan2(p_vector.x, p_vector.z)) * 8.0 / (Math_PI * 2.0) + 0.5)) % 8;
return lon + (lat - 1) * 8;
}
_FORCE_INLINE_ static int get_uv84_normal_bit_neighbors(int p_idx) {
if (p_idx == 24) {
return 1 | 2 | 4 | 8;
} else if (p_idx == 25) {
return (1 << 23) | (1 << 22) | (1 << 21) | (1 << 20);
} else {
int ret = 0;
if ((p_idx % 8) == 0) {
ret |= (1 << (p_idx + 7));
} else {
ret |= (1 << (p_idx - 1));
}
if ((p_idx % 8) == 7) {
ret |= (1 << (p_idx - 7));
} else {
ret |= (1 << (p_idx + 1));
}
int mask = ret | (1 << p_idx);
if (p_idx < 8) {
ret |= 24;
} else {
ret |= mask >> 8;
}
if (p_idx >= 16) {
ret |= 25;
} else {
ret |= mask << 8;
}
return ret;
}
}
static real_t vec2_cross(const Point2 &O, const Point2 &A, const Point2 &B) {
return (real_t)(A.x - O.x) * (B.y - O.y) - (real_t)(A.y - O.y) * (B.x - O.x);
}
// Returns a list of points on the convex hull in counter-clockwise order.
// Note: the last point in the returned list is the same as the first one.
static Vector<Point2> convex_hull_2d(Vector<Point2> P) {
int n = P.size(), k = 0;
Vector<Point2> H;
H.resize(2 * n);
// Sort points lexicographically.
P.sort();
// Build lower hull.
for (int i = 0; i < n; ++i) {
while (k >= 2 && vec2_cross(H[k - 2], H[k - 1], P[i]) <= 0) {
k--;
}
H.write[k++] = P[i];
}
// Build upper hull.
for (int i = n - 2, t = k + 1; i >= 0; i--) {
while (k >= t && vec2_cross(H[k - 2], H[k - 1], P[i]) <= 0) {
k--;
}
H.write[k++] = P[i];
}
H.resize(k);
return H;
}
static Vector<Vector<Vector2>> decompose_polygon_in_convex(Vector<Point2> polygon);
static MeshData build_convex_mesh(const PoolVector<Plane> &p_planes);
static PoolVector<Plane> build_sphere_planes(real_t p_radius, int p_lats, int p_lons, Vector3::Axis p_axis = Vector3::AXIS_Z);
static PoolVector<Plane> build_box_planes(const Vector3 &p_extents);
static PoolVector<Plane> build_cylinder_planes(real_t p_radius, real_t p_height, int p_sides, Vector3::Axis p_axis = Vector3::AXIS_Z);
static PoolVector<Plane> build_capsule_planes(real_t p_radius, real_t p_height, int p_sides, int p_lats, Vector3::Axis p_axis = Vector3::AXIS_Z);
static void sort_polygon_winding(Vector<Vector2> &r_verts, bool p_clockwise = true);
static real_t find_polygon_area(const Vector3 *p_verts, int p_num_verts);
static void make_atlas(const Vector<Size2i> &p_rects, Vector<Point2i> &r_result, Size2i &r_size);
struct PackRectsResult {
int x;
int y;
bool packed;
};
static Vector<PackRectsResult> partial_pack_rects(const Vector<Vector2i> &p_sizes, const Size2i &p_atlas_size);
static Vector<Vector3> compute_convex_mesh_points(const Plane *p_planes, int p_plane_count, real_t p_epsilon = CMP_EPSILON);
static bool convex_hull_intersects_convex_hull(const Plane *p_planes_a, int p_plane_count_a, const Plane *p_planes_b, int p_plane_count_b);
static real_t calculate_convex_hull_volume(const Geometry::MeshData &p_md);
private:
static Vector<Vector<Point2>> _polypaths_do_operation(PolyBooleanOperation p_op, const Vector<Point2> &p_polypath_a, const Vector<Point2> &p_polypath_b, bool is_a_open = false);
static Vector<Vector<Point2>> _polypath_offset(const Vector<Point2> &p_polypath, real_t p_delta, PolyJoinType p_join_type, PolyEndType p_end_type);
};
#endif // GEOMETRY_H
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