bounding box

include/cglm/box.h

@@ -0,0 +1,123 @@
+/*
+ * 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"
+
+/*!
+ * @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, tmp;
+
+  glm_vec_scale(m[0], box[0][0], xa);
+  glm_vec_scale(m[0], box[1][0], xb);
+
+  glm_vec_scale(m[1], box[0][1], ya);
+  glm_vec_scale(m[1], box[1][1], yb);
+
+  glm_vec_scale(m[2], box[0][2], za);
+  glm_vec_scale(m[2], box[1][2], zb);
+
+  /* min(xa, xb) + min(ya, yb) + min(za, zb) + translation */
+  glm_vec_minv(xa, xb, v[0]);
+  glm_vec_minv(ya, yb, tmp);
+  glm_vec_add(v[0], tmp, v[0]);
+  glm_vec_minv(za, zb, tmp);
+  glm_vec_add(v[0], tmp, v[0]);
+  glm_vec_add(v[0], m[3], v[0]);
+
+  /* max(xa, xb) + max(ya, yb) + max(za, zb) + translation */
+  glm_vec_maxv(xa, xb, v[1]);
+  glm_vec_maxv(ya, yb, tmp);
+  glm_vec_add(v[1], tmp, v[1]);
+  glm_vec_maxv(za, zb, tmp);
+  glm_vec_add(v[1], tmp, v[1]);
+  glm_vec_add(v[1], m[3], v[1]);
+
+  glm_vec_copy(v[0], dest[0]);
+  glm_vec_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 gettng 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 gettng 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 miniumum 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);
+}
+
+#endif /* cglm_box_h */

include/cglm/call.h

@@ -22,6 +22,7 @@ extern "C" {
 #include "call/euler.h"
 #include "call/plane.h"
 #include "call/frustum.h"
+#include "call/box.h"
 #include "call/io.h"
 
 #ifdef __cplusplus

include/cglm/call/box.h

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c), Recep Aslantas.
+ *
+ * MIT License (MIT), http://opensource.org/licenses/MIT
+ * Full license can be found in the LICENSE file
+ */
+
+#ifndef cglmc_box_h
+#define cglmc_box_h
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "../cglm.h"
+
+CGLM_EXPORT
+void
+glmc_aabb_transform(vec3 box[2], mat4 m, vec3 dest[2]);
+
+CGLM_EXPORT
+void
+glmc_aabb_merge(vec3 box1[2], vec3 box2[2], vec3 dest[2]);
+
+CGLM_EXPORT
+void
+glmc_aabb_crop(vec3 box[2], vec3 cropBox[2], vec3 dest[2]);
+
+CGLM_EXPORT
+void
+glmc_aabb_crop_until(vec3 box[2],
+                     vec3 cropBox[2],
+                     vec3 clampBox[2],
+                     vec3 dest[2]);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* cglmc_box_h */
+

include/cglm/cglm.h

@@ -19,6 +19,7 @@
 #include "quat.h"
 #include "euler.h"
 #include "plane.h"
+#include "box.h"
 #include "util.h"
 #include "io.h"