CubicSDR/external/cubicvr2/math/aabb.h

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//
// aabb.h
// CubicVR2
//
// Created by Charles J. Cliffe on 2013-02-22.
// Copyright (c) 2013 Charles J. Cliffe. All rights reserved.
//
#ifndef __CubicVR2__aabb__
#define __CubicVR2__aabb__
#include <iostream>
#include "vec3.h"
namespace CubicVR {
enum aabb_enum { AABB_DISJOINT, AABB_A_INSIDE_B, AABB_B_INSIDE_A, AABB_INTERSECT };
struct aabb {
vec3 min, max;
aabb(vec3 min_in, vec3 max_in) {
min=min_in;
max=max_in;
}
aabb() {
min=max=vec3(0,0,0);
}
aabb engulf(aabb aabb, vec3 point) {
if (aabb.min[0] > point[0]) {
aabb.min[0] = point[0];
}
if (aabb.min[1] > point[1]) {
aabb.min[1] = point[1];
}
if (aabb.min[2] > point[2]) {
aabb.min[2] = point[2];
}
if (aabb.max[0] < point[0]) {
aabb.max[0] = point[0];
}
if (aabb.max[1] < point[1]) {
aabb.max[1] = point[1];
}
if (aabb.max[2] < point[2]) {
aabb.max[2] = point[2];
}
return aabb;
};
static aabb reset(aabb aabb, vec3 point=vec3(0.0f,0.0f,0.0f)) {
aabb.min[0] = point[0];
aabb.min[1] = point[1];
aabb.min[2] = point[2];
aabb.max[0] = point[0];
aabb.max[1] = point[1];
aabb.max[2] = point[2];
return aabb;
};
static vec3 size(aabb aabb) {
__float x = aabb.min[0] < aabb.max[0] ? aabb.max[0] - aabb.min[0] : aabb.min[0] - aabb.max[0];
__float y = aabb.min[1] < aabb.max[1] ? aabb.max[1] - aabb.min[1] : aabb.min[1] - aabb.max[1];
__float z = aabb.min[2] < aabb.max[2] ? aabb.max[2] - aabb.min[2] : aabb.min[2] - aabb.max[2];
return vec3(x,y,z);
};
/**
Returns positive integer if intersect between A and B, 0 otherwise.
For more detailed intersect result check value:
CubicVR.enums.aabb.INTERSECT if AABBs intersect
CubicVR.enums.aabb.A_INSIDE_B if boxA is inside boxB
CubicVR.enums.aabb.B_INSIDE_A if boxB is inside boxA
CubicVR.enums.aabb.DISJOINT if AABBs are disjoint (do not intersect)
*/
aabb_enum intersects(aabb boxA, aabb boxB) {
// Disjoint
if( boxA.min[0] > boxB.max[0] || boxA.max[0] < boxB.min[0] ){
return AABB_DISJOINT;
}
if( boxA.min[1] > boxB.max[1] || boxA.max[1] < boxB.min[1] ){
return AABB_DISJOINT;
}
if( boxA.min[2] > boxB.max[2] || boxA.max[2] < boxB.min[2] ){
return AABB_DISJOINT;
}
// boxA is inside boxB.
if( boxA.min[0] >= boxB.min[0] && boxA.max[0] <= boxB.max[0] &&
boxA.min[1] >= boxB.min[1] && boxA.max[1] <= boxB.max[1] &&
boxA.min[2] >= boxB.min[2] && boxA.max[2] <= boxB.max[2]) {
return AABB_A_INSIDE_B;
}
// boxB is inside boxA.
if( boxB.min[0] >= boxA.min[0] && boxB.max[0] <= boxA.max[0] &&
boxB.min[1] >= boxA.min[1] && boxB.max[1] <= boxA.max[1] &&
boxB.min[2] >= boxA.min[2] && boxB.max[2] <= boxA.max[2]) {
return AABB_B_INSIDE_A;
}
// Otherwise AABB's intersect.
return AABB_INTERSECT;
}
};
};
#endif /* defined(__CubicVR2__aabb__) */