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diff --git a/include/cglm/struct/frustum.h b/include/cglm/struct/frustum.h
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+++ b/include/cglm/struct/frustum.h
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+/*
+ * Copyright (c), Recep Aslantas.
+ *
+ * MIT License (MIT), http://opensource.org/licenses/MIT
+ * Full license can be found in the LICENSE file
+ */
+
+#ifndef cglms_frustums_h
+#define cglms_frustums_h
+
+#include "../common.h"
+#include "../types-struct.h"
+#include "../frustum.h"
+#include "plane.h"
+#include "vec3.h"
+#include "vec4.h"
+#include "mat4.h"
+
+/* you can override clip space coords
+   but you have to provide all with same name
+   e.g.: define GLM_CSCOORD_LBN {0.0f, 0.0f, 1.0f, 1.0f} */
+#ifndef GLM_CUSTOM_CLIPSPACE
+
+/* near */
+#define GLMS_CSCOORD_LBN {-1.0f, -1.0f, -1.0f, 1.0f}
+#define GLMS_CSCOORD_LTN {-1.0f,  1.0f, -1.0f, 1.0f}
+#define GLMS_CSCOORD_RTN { 1.0f,  1.0f, -1.0f, 1.0f}
+#define GLMS_CSCOORD_RBN { 1.0f, -1.0f, -1.0f, 1.0f}
+
+/* far */
+#define GLMS_CSCOORD_LBF {-1.0f, -1.0f,  1.0f, 1.0f}
+#define GLMS_CSCOORD_LTF {-1.0f,  1.0f,  1.0f, 1.0f}
+#define GLMS_CSCOORD_RTF { 1.0f,  1.0f,  1.0f, 1.0f}
+#define GLMS_CSCOORD_RBF { 1.0f, -1.0f,  1.0f, 1.0f}
+
+#endif
+
+/*!
+ * @brief extracts view frustum planes
+ *
+ * planes' space:
+ *  1- if m = proj:     View Space
+ *  2- if m = viewProj: World Space
+ *  3- if m = MVP:      Object Space
+ *
+ * You probably want to extract planes in world space so use viewProj as m
+ * Computing viewProj:
+ *   glm_mat4_mul(proj, view, viewProj);
+ *
+ * Exracted planes order: [left, right, bottom, top, near, far]
+ *
+ * @param[in]  m    matrix (see brief)
+ * @param[out] dest extracted view frustum planes (see brief)
+ */
+CGLM_INLINE
+void
+glms_frustum_planes(mat4s m, vec4s dest[6]) {
+  vec4 rawDest[6];
+  glm_frustum_planes(m.raw, rawDest);
+  glms_vec4_(pack)(dest, rawDest, 6);
+}
+
+/*!
+ * @brief extracts view frustum corners using clip-space coordinates
+ *
+ * corners' space:
+ *  1- if m = invViewProj: World Space
+ *  2- if m = invMVP:      Object Space
+ *
+ * You probably want to extract corners in world space so use invViewProj
+ * Computing invViewProj:
+ *   glm_mat4_mul(proj, view, viewProj);
+ *   ...
+ *   glm_mat4_inv(viewProj, invViewProj);
+ *
+ * if you have a near coord at i index, you can get it's far coord by i + 4
+ *
+ * Find center coordinates:
+ *   for (j = 0; j < 4; j++) {
+ *     glm_vec3_center(corners[i], corners[i + 4], centerCorners[i]);
+ *   }
+ *
+ * @param[in]  invMat matrix (see brief)
+ * @param[out] dest   exracted view frustum corners (see brief)
+ */
+CGLM_INLINE
+void
+glms_frustum_corners(mat4s invMat, vec4s dest[8]) {
+  vec4 rawDest[8];
+  glm_frustum_corners(invMat.raw, rawDest);
+  glms_vec4_(pack)(dest, rawDest, 8);
+}
+
+/*!
+ * @brief finds center of view frustum
+ *
+ * @param[in]  corners view frustum corners
+ * @returns            view frustum center
+ */
+CGLM_INLINE
+vec4s
+glms_frustum_center(vec4s corners[8]) {
+  vec4 rawCorners[8];
+  vec4s r;
+
+  glms_vec4_(unpack)(rawCorners, corners, 8);
+  glm_frustum_center(rawCorners, r.raw);
+  return r;
+}
+
+/*!
+ * @brief finds bounding box of frustum relative to given matrix e.g. view mat
+ *
+ * @param[in]  corners view frustum corners
+ * @param[in]  m       matrix to convert existing conners
+ * @param[out] box     bounding box as array [min, max]
+ */
+CGLM_INLINE
+void
+glms_frustum_box(vec4s corners[8], mat4s m, vec3s box[2]) {
+  vec4 rawCorners[8];
+  vec3 rawBox[2];
+
+  glms_vec4_(unpack)(rawCorners, corners, 8);
+  glm_frustum_box(rawCorners, m.raw, rawBox);
+  glms_vec3_(pack)(box, rawBox, 2);
+}
+
+/*!
+ * @brief finds planes corners which is between near and far planes (parallel)
+ *
+ * this will be helpful if you want to split a frustum e.g. CSM/PSSM. This will
+ * find planes' corners but you will need to one more plane.
+ * Actually you have it, it is near, far or created previously with this func ;)
+ *
+ * @param[in]  corners view  frustum corners
+ * @param[in]  splitDist     split distance
+ * @param[in]  farDist       far distance (zFar)
+ * @param[out] planeCorners  plane corners [LB, LT, RT, RB]
+ */
+CGLM_INLINE
+void
+glms_frustum_corners_at(vec4s corners[8],
+                        float splitDist,
+                        float farDist,
+                        vec4s planeCorners[4]) {
+  vec4 rawCorners[8];
+  vec4 rawPlaneCorners[4];
+
+  glms_vec4_(unpack)(rawCorners, corners, 8);
+  glm_frustum_corners_at(rawCorners, splitDist, farDist, rawPlaneCorners);
+  glms_vec4_(pack)(planeCorners, rawPlaneCorners, 8);
+}
+
+#endif /* cglms_frustums_h */