virtualx-engine/core/math/geometry.h
Rémi Verschelde 1426cd3b3a
One Copyright Update to rule them all
As many open source projects have started doing it, we're removing the
current year from the copyright notice, so that we don't need to bump
it every year.

It seems like only the first year of publication is technically
relevant for copyright notices, and even that seems to be something
that many companies stopped listing altogether (in a version controlled
codebase, the commits are a much better source of date of publication
than a hardcoded copyright statement).

We also now list Godot Engine contributors first as we're collectively
the current maintainers of the project, and we clarify that the
"exclusive" copyright of the co-founders covers the timespan before
opensourcing (their further contributions are included as part of Godot
Engine contributors).

Also fixed "cf." Frenchism - it's meant as "refer to / see".

Backported from #70885.
2023-01-10 15:26:54 +01:00

1029 lines
30 KiB
C++

/**************************************************************************/
/* geometry.h */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#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