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Diffstat (limited to 'include/cglm/box.h')
| -rw-r--r-- | include/cglm/box.h | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/include/cglm/box.h b/include/cglm/box.h new file mode 100644 index 0000000..8bba678 --- /dev/null +++ b/include/cglm/box.h @@ -0,0 +1,281 @@ +/* + * 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 */ |