/*
* Copyright (c), Recep Aslantas.
*
* MIT License (MIT), http://opensource.org/licenses/MIT
* Full license can be found in the LICENSE file
*/
#ifndef cglm_box_h
#define cglm_box_h
#include "common.h"
#include "vec3.h"
#include "vec4.h"
#include "util.h"
/*!
* @brief apply transform to Axis-Aligned Bounding Box
*
* @param[in] box bounding box
* @param[in] m transform matrix
* @param[out] dest transformed bounding box
*/
CGLM_INLINE
void
glm_aabb_transform(vec3 box[2], mat4 m, vec3 dest[2]) {
vec3 v[2], xa, xb, ya, yb, za, zb;
glm_vec3_scale(m[0], box[0][0], xa);
glm_vec3_scale(m[0], box[1][0], xb);
glm_vec3_scale(m[1], box[0][1], ya);
glm_vec3_scale(m[1], box[1][1], yb);
glm_vec3_scale(m[2], box[0][2], za);
glm_vec3_scale(m[2], box[1][2], zb);
/* translation + min(xa, xb) + min(ya, yb) + min(za, zb) */
glm_vec3(m[3], v[0]);
glm_vec3_minadd(xa, xb, v[0]);
glm_vec3_minadd(ya, yb, v[0]);
glm_vec3_minadd(za, zb, v[0]);
/* translation + max(xa, xb) + max(ya, yb) + max(za, zb) */
glm_vec3(m[3], v[1]);
glm_vec3_maxadd(xa, xb, v[1]);
glm_vec3_maxadd(ya, yb, v[1]);
glm_vec3_maxadd(za, zb, v[1]);
glm_vec3_copy(v[0], dest[0]);
glm_vec3_copy(v[1], dest[1]);
}
/*!
* @brief merges two AABB bounding box and creates new one
*
* two box must be in same space, if one of box is in different space then
* you should consider to convert it's space by glm_box_space
*
* @param[in] box1 bounding box 1
* @param[in] box2 bounding box 2
* @param[out] dest merged bounding box
*/
CGLM_INLINE
void
glm_aabb_merge(vec3 box1[2], vec3 box2[2], vec3 dest[2]) {
dest[0][0] = glm_min(box1[0][0], box2[0][0]);
dest[0][1] = glm_min(box1[0][1], box2[0][1]);
dest[0][2] = glm_min(box1[0][2], box2[0][2]);
dest[1][0] = glm_max(box1[1][0], box2[1][0]);
dest[1][1] = glm_max(box1[1][1], box2[1][1]);
dest[1][2] = glm_max(box1[1][2], box2[1][2]);
}
/*!
* @brief crops a bounding box with another one.
*
* this could be useful for getting a bbox which fits with view frustum and
* object bounding boxes. In this case you crop view frustum box with objects
* box
*
* @param[in] box bounding box 1
* @param[in] cropBox crop box
* @param[out] dest cropped bounding box
*/
CGLM_INLINE
void
glm_aabb_crop(vec3 box[2], vec3 cropBox[2], vec3 dest[2]) {
dest[0][0] = glm_max(box[0][0], cropBox[0][0]);
dest[0][1] = glm_max(box[0][1], cropBox[0][1]);
dest[0][2] = glm_max(box[0][2], cropBox[0][2]);
dest[1][0] = glm_min(box[1][0], cropBox[1][0]);
dest[1][1] = glm_min(box[1][1], cropBox[1][1]);
dest[1][2] = glm_min(box[1][2], cropBox[1][2]);
}
/*!
* @brief crops a bounding box with another one.
*
* this could be useful for getting a bbox which fits with view frustum and
* object bounding boxes. In this case you crop view frustum box with objects
* box
*
* @param[in] box bounding box
* @param[in] cropBox crop box
* @param[in] clampBox minimum box
* @param[out] dest cropped bounding box
*/
CGLM_INLINE
void
glm_aabb_crop_until(vec3 box[2],
vec3 cropBox[2],
vec3 clampBox[2],
vec3 dest[2]) {
glm_aabb_crop(box, cropBox, dest);
glm_aabb_merge(clampBox, dest, dest);
}
/*!
* @brief check if AABB intersects with frustum planes
*
* this could be useful for frustum culling using AABB.
*
* OPTIMIZATION HINT:
* if planes order is similar to LEFT, RIGHT, BOTTOM, TOP, NEAR, FAR
* then this method should run even faster because it would only use two
* planes if object is not inside the two planes
* fortunately cglm extracts planes as this order! just pass what you got!
*
* @param[in] box bounding box
* @param[in] planes frustum planes
*/
CGLM_INLINE
bool
glm_aabb_frustum(vec3 box[2], vec4 planes[6]) {
float *p, dp;
int i;
for (i = 0; i < 6; i++) {
p = planes[i];
dp = p[0] * box[p[0] > 0.0f][0]
+ p[1] * box[p[1] > 0.0f][1]
+ p[2] * box[p[2] > 0.0f][2];
if (dp < -p[3])
return false;
}
return true;
}
/*!
* @brief invalidate AABB min and max values
*
* @param[in, out] box bounding box
*/
CGLM_INLINE
void
glm_aabb_invalidate(vec3 box[2]) {
glm_vec3_broadcast(FLT_MAX, box[0]);
glm_vec3_broadcast(-FLT_MAX, box[1]);
}
/*!
* @brief check if AABB is valid or not
*
* @param[in] box bounding box
*/
CGLM_INLINE
bool
glm_aabb_isvalid(vec3 box[2]) {
return glm_vec3_max(box[0]) != FLT_MAX
&& glm_vec3_min(box[1]) != -FLT_MAX;
}
/*!
* @brief distance between of min and max
*
* @param[in] box bounding box
*/
CGLM_INLINE
float
glm_aabb_size(vec3 box[2]) {
return glm_vec3_distance(box[0], box[1]);
}
/*!
* @brief radius of sphere which surrounds AABB
*
* @param[in] box bounding box
*/
CGLM_INLINE
float
glm_aabb_radius(vec3 box[2]) {
return glm_aabb_size(box) * 0.5f;
}
/*!
* @brief computes center point of AABB
*
* @param[in] box bounding box
* @param[out] dest center of bounding box
*/
CGLM_INLINE
void
glm_aabb_center(vec3 box[2], vec3 dest) {
glm_vec3_center(box[0], box[1], dest);
}
/*!
* @brief check if two AABB intersects
*
* @param[in] box bounding box
* @param[in] other other bounding box
*/
CGLM_INLINE
bool
glm_aabb_aabb(vec3 box[2], vec3 other[2]) {
return (box[0][0] <= other[1][0] && box[1][0] >= other[0][0])
&& (box[0][1] <= other[1][1] && box[1][1] >= other[0][1])
&& (box[0][2] <= other[1][2] && box[1][2] >= other[0][2]);
}
/*!
* @brief check if AABB intersects with sphere
*
* https://github.com/erich666/GraphicsGems/blob/master/gems/BoxSphere.c
* Solid Box - Solid Sphere test.
*
* Sphere Representation in cglm: [center.x, center.y, center.z, radii]
*
* @param[in] box solid bounding box
* @param[in] s solid sphere
*/
CGLM_INLINE
bool
glm_aabb_sphere(vec3 box[2], vec4 s) {
float dmin;
int a, b, c;
a = (s[0] < box[0][0]) + (s[0] > box[1][0]);
b = (s[1] < box[0][1]) + (s[1] > box[1][1]);
c = (s[2] < box[0][2]) + (s[2] > box[1][2]);
dmin = glm_pow2((s[0] - box[!(a - 1)][0]) * (a != 0))
+ glm_pow2((s[1] - box[!(b - 1)][1]) * (b != 0))
+ glm_pow2((s[2] - box[!(c - 1)][2]) * (c != 0));
return dmin <= glm_pow2(s[3]);
}
/*!
* @brief check if point is inside of AABB
*
* @param[in] box bounding box
* @param[in] point point
*/
CGLM_INLINE
bool
glm_aabb_point(vec3 box[2], vec3 point) {
return (point[0] >= box[0][0] && point[0] <= box[1][0])
&& (point[1] >= box[0][1] && point[1] <= box[1][1])
&& (point[2] >= box[0][2] && point[2] <= box[1][2]);
}
/*!
* @brief check if AABB contains other AABB
*
* @param[in] box bounding box
* @param[in] other other bounding box
*/
CGLM_INLINE
bool
glm_aabb_contains(vec3 box[2], vec3 other[2]) {
return (box[0][0] <= other[0][0] && box[1][0] >= other[1][0])
&& (box[0][1] <= other[0][1] && box[1][1] >= other[1][1])
&& (box[0][2] <= other[0][2] && box[1][2] >= other[1][2]);
}
#endif /* cglm_box_h */