move frustum related stuff to frustum header

* create helpers macro which defines corner index
* func for get bounding box frustum
* add missing source to make file
* add more desc to glm_frustum_corners

include/cglm/call/cam.h

@@ -53,18 +53,6 @@ CGLM_EXPORT
 void
 glmc_look_anyup(vec3 eye, vec3 dir, mat4 dest);
 
-CGLM_EXPORT
-void
-glmc_frustum_planes(mat4 m, vec4 dest[6]);
-
-CGLM_EXPORT
-void
-glmc_frustum_corners(mat4 invMat, vec4 dest[8]);
-
-CGLM_EXPORT
-void
-glmc_frustum_center(vec4 corners[8], vec4 dest);
-
 #ifdef __cplusplus
 }
 #endif

include/cglm/call/frustum.h

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c), Recep Aslantas.
+ *
+ * MIT License (MIT), http://opensource.org/licenses/MIT
+ * Full license can be found in the LICENSE file
+ */
+
+#ifndef cglmc_frustum_h
+#define cglmc_frustum_h
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "../cglm.h"
+
+CGLM_EXPORT
+void
+glmc_frustum_planes(mat4 m, vec4 dest[6]);
+
+CGLM_EXPORT
+void
+glmc_frustum_corners(mat4 invMat, vec4 dest[8]);
+
+CGLM_EXPORT
+void
+glmc_frustum_center(vec4 corners[8], vec4 dest);
+
+CGLM_EXPORT
+void
+glmc_frustum_box(vec4 corners[8], mat4 m, vec3 box[2]);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* cglmc_frustum_h */