gdnative_cpp/core/rect2.cpp
2023-10-23 19:24:53 +02:00

320 lines
8.4 KiB
C++

/*************************************************************************/
/* Rect2.cpp */
/*************************************************************************/
/* This file is part of: */
/* PANDEMONIUM ENGINE */
/* https://pandemoniumengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2022 Pandemonium Engine contributors (cf. AUTHORS.md). */
/* */
/* 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. */
/*************************************************************************/
#include "rect2.h"
#include "transform_2d.h"
#include "ustring.h"
#include "vector2.h"
#include <cmath>
#ifndef MAX
#define MAX(a, b) (a > b ? a : b)
#endif
#ifndef MIN
#define MIN(a, b) (a < b ? a : b)
#endif
real_t Rect2::distance_to(const Vector2 &p_point) const {
real_t dist = 0.0;
bool inside = true;
if (p_point.x < position.x) {
real_t d = position.x - p_point.x;
dist = d;
inside = false;
}
if (p_point.y < position.y) {
real_t d = position.y - p_point.y;
dist = inside ? d : MIN(dist, d);
inside = false;
}
if (p_point.x >= (position.x + size.x)) {
real_t d = p_point.x - (position.x + size.x);
dist = inside ? d : MIN(dist, d);
inside = false;
}
if (p_point.y >= (position.y + size.y)) {
real_t d = p_point.y - (position.y + size.y);
dist = inside ? d : MIN(dist, d);
inside = false;
}
if (inside) {
return 0;
} else {
return dist;
}
}
Rect2 Rect2::clip(const Rect2 &p_rect) const { /// return a clipped rect
Rect2 new_rect = p_rect;
if (!intersects(new_rect))
return Rect2();
new_rect.position.x = MAX(p_rect.position.x, position.x);
new_rect.position.y = MAX(p_rect.position.y, position.y);
Point2 p_rect_end = p_rect.position + p_rect.size;
Point2 end = position + size;
new_rect.size.x = MIN(p_rect_end.x, end.x) - new_rect.position.x;
new_rect.size.y = MIN(p_rect_end.y, end.y) - new_rect.position.y;
return new_rect;
}
Rect2 Rect2::merge(const Rect2 &p_rect) const { ///< return a merged rect
Rect2 new_rect;
new_rect.position.x = MIN(p_rect.position.x, position.x);
new_rect.position.y = MIN(p_rect.position.y, position.y);
new_rect.size.x = MAX(p_rect.position.x + p_rect.size.x, position.x + size.x);
new_rect.size.y = MAX(p_rect.position.y + p_rect.size.y, position.y + size.y);
new_rect.size = new_rect.size - new_rect.position; // make relative again
return new_rect;
}
Rect2::operator String() const {
return String(position) + ", " + String(size);
}
bool Rect2::intersects_segment(const Point2 &p_from, const Point2 &p_to, Point2 *r_position, Point2 *r_normal) const {
real_t min = 0, max = 1;
int axis = 0;
real_t sign = 0;
for (int i = 0; i < 2; i++) {
real_t seg_from = p_from[i];
real_t seg_to = p_to[i];
real_t box_begin = position[i];
real_t box_end = box_begin + size[i];
real_t cmin, cmax;
real_t csign;
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;
csign = -1.0;
} 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;
csign = 1.0;
}
if (cmin > min) {
min = cmin;
axis = i;
sign = csign;
}
if (cmax < max)
max = cmax;
if (max < min)
return false;
}
Vector2 rel = p_to - p_from;
if (r_normal) {
Vector2 normal;
normal[axis] = sign;
*r_normal = normal;
}
if (r_position)
*r_position = p_from + rel * min;
return true;
}
bool Rect2::intersects_transformed(const Transform2D &p_xform, const Rect2 &p_rect) const {
// SAT intersection between local and transformed rect2
Vector2 xf_points[4] = {
p_xform.xform(p_rect.position),
p_xform.xform(Vector2(p_rect.position.x + p_rect.size.x, p_rect.position.y)),
p_xform.xform(Vector2(p_rect.position.x, p_rect.position.y + p_rect.size.y)),
p_xform.xform(Vector2(p_rect.position.x + p_rect.size.x, p_rect.position.y + p_rect.size.y)),
};
real_t low_limit;
// base rect2 first (faster)
if (xf_points[0].y > position.y)
goto next1;
if (xf_points[1].y > position.y)
goto next1;
if (xf_points[2].y > position.y)
goto next1;
if (xf_points[3].y > position.y)
goto next1;
return false;
next1:
low_limit = position.y + size.y;
if (xf_points[0].y < low_limit)
goto next2;
if (xf_points[1].y < low_limit)
goto next2;
if (xf_points[2].y < low_limit)
goto next2;
if (xf_points[3].y < low_limit)
goto next2;
return false;
next2:
if (xf_points[0].x > position.x)
goto next3;
if (xf_points[1].x > position.x)
goto next3;
if (xf_points[2].x > position.x)
goto next3;
if (xf_points[3].x > position.x)
goto next3;
return false;
next3:
low_limit = position.x + size.x;
if (xf_points[0].x < low_limit)
goto next4;
if (xf_points[1].x < low_limit)
goto next4;
if (xf_points[2].x < low_limit)
goto next4;
if (xf_points[3].x < low_limit)
goto next4;
return false;
next4:
Vector2 xf_points2[4] = {
position,
Vector2(position.x + size.x, position.y),
Vector2(position.x, position.y + size.y),
Vector2(position.x + size.x, position.y + size.y),
};
real_t maxa = p_xform.elements[0].dot(xf_points2[0]);
real_t mina = maxa;
real_t dp = p_xform.elements[0].dot(xf_points2[1]);
maxa = MAX(dp, maxa);
mina = MIN(dp, mina);
dp = p_xform.elements[0].dot(xf_points2[2]);
maxa = MAX(dp, maxa);
mina = MIN(dp, mina);
dp = p_xform.elements[0].dot(xf_points2[3]);
maxa = MAX(dp, maxa);
mina = MIN(dp, mina);
real_t maxb = p_xform.elements[0].dot(xf_points[0]);
real_t minb = maxb;
dp = p_xform.elements[0].dot(xf_points[1]);
maxb = MAX(dp, maxb);
minb = MIN(dp, minb);
dp = p_xform.elements[0].dot(xf_points[2]);
maxb = MAX(dp, maxb);
minb = MIN(dp, minb);
dp = p_xform.elements[0].dot(xf_points[3]);
maxb = MAX(dp, maxb);
minb = MIN(dp, minb);
if (mina > maxb)
return false;
if (minb > maxa)
return false;
maxa = p_xform.elements[1].dot(xf_points2[0]);
mina = maxa;
dp = p_xform.elements[1].dot(xf_points2[1]);
maxa = MAX(dp, maxa);
mina = MIN(dp, mina);
dp = p_xform.elements[1].dot(xf_points2[2]);
maxa = MAX(dp, maxa);
mina = MIN(dp, mina);
dp = p_xform.elements[1].dot(xf_points2[3]);
maxa = MAX(dp, maxa);
mina = MIN(dp, mina);
maxb = p_xform.elements[1].dot(xf_points[0]);
minb = maxb;
dp = p_xform.elements[1].dot(xf_points[1]);
maxb = MAX(dp, maxb);
minb = MIN(dp, minb);
dp = p_xform.elements[1].dot(xf_points[2]);
maxb = MAX(dp, maxb);
minb = MIN(dp, minb);
dp = p_xform.elements[1].dot(xf_points[3]);
maxb = MAX(dp, maxb);
minb = MIN(dp, minb);
if (mina > maxb)
return false;
if (minb > maxa)
return false;
return true;
}