docs: add docs for quaternions

docs/source/api.rst

@@ -29,6 +29,7 @@ Follow the :doc:`build` documentation for this
    affine
    affine-mat
    cam
+   quat
    mat4
    mat3
    vec3

docs/source/quat.rst

@@ -0,0 +1,124 @@
+.. default-domain:: C
+
+Quaternions
+===========
+
+Header: cglm/quat.h
+
+ **Important:** *cglm* stores quaternion as [w, x, y, z] in memory, don't
+ forget that when changing quaternion items manually. For instance *quat[3]*
+ is *quat.z* and *quat[0*] is *quat.w*. This may change in the future if *cglm*
+ will got enough request to do that. Probably it will not be changed in near
+ future
+
+There are some TODOs for quaternions check TODO list to see them.
+
+Also **versor** is identity quaternion so the type may change to **vec4** or
+something else. This will not affect existing functions for your engine because
+*versor* is alias of *vec4*
+
+Table of contents (click to go):
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Macros:
+
+1. GLM_QUAT_IDENTITY_INIT
+#. GLM_QUAT_IDENTITY
+
+Functions:
+
+1. :c:func:`glm_quat_identity`
+#. :c:func:`glm_quat`
+#. :c:func:`glm_quatv`
+#. :c:func:`glm_quat_norm`
+#. :c:func:`glm_quat_normalize`
+#. :c:func:`glm_quat_dot`
+#. :c:func:`glm_quat_mulv`
+#. :c:func:`glm_quat_mat4`
+#. :c:func:`glm_quat_slerp`
+
+Functions documentation
+~~~~~~~~~~~~~~~~~~~~~~~
+
+.. c:function:: void  glm_quat_identity(versor q)
+
+    | makes given quat to identity
+
+    Parameters:
+      | *[in, out]*  **q**    quaternion
+
+.. c:function:: void  glm_quat(versor q, float  angle, float  x, float  y, float  z)
+
+    | creates NEW quaternion with individual axis components
+
+    Parameters:
+      | *[out]* **q**      quaternion
+      | *[in]*  **angle**  angle (radians)
+      | *[in]*  **x**      axis.x
+      | *[in]*  **y**      axis.y
+      | *[in]*  **z**      axis.z
+
+.. c:function:: void  glm_quatv(versor q, float  angle, vec3   v)
+
+    | creates NEW quaternion with axis vector
+
+    Parameters:
+      | *[out]* **q**      quaternion
+      | *[in]*  **angle**  angle (radians)
+      | *[in]*  **v**      axis
+
+.. c:function:: float  glm_quat_norm(versor q)
+
+    | returns norm (magnitude) of quaternion
+
+    Parameters:
+      | *[in]*  **a**  quaternion
+
+    Returns:
+      norm (magnitude)
+
+.. c:function:: void  glm_quat_normalize(versor q)
+
+    | normalize quaternion
+
+    Parameters:
+      | *[in, out]*  **q** quaternion
+
+.. c:function:: float  glm_quat_dot(versor q, versor r)
+
+    dot product of two quaternion
+
+    Parameters:
+      | *[in]*  **q1**   quaternion 1
+      | *[in]*  **q2**   quaternion 2
+
+    Returns:
+      dot product
+
+.. c:function:: void  glm_quat_mulv(versor q1, versor q2, versor dest)
+
+    | multiplies two quaternion and stores result in dest
+
+    Parameters:
+      | *[in]*  **q1**    quaternion 1
+      | *[in]*  **q2**    quaternion 2
+      | *[out]* **dest**  result quaternion
+
+.. c:function:: void  glm_quat_mat4(versor q, mat4 dest)
+
+    | convert quaternion to mat4
+
+    Parameters:
+      | *[in]*  **q**     quaternion
+      | *[out]* **dest**  result matrix
+
+.. c:function:: void glm_quat_slerp(versor q, versor r, float  t, versor dest)
+
+    | interpolates between two quaternions
+    | using spherical linear interpolation (SLERP)
+
+    Parameters:
+      | *[in]*  **q**     from
+      | *[in]*  **r**     to
+      | *[in]*  **t**     amout
+      | *[out]* **dest**  result quaternion

docs/source/vec3.rst

@@ -67,7 +67,7 @@ Functions documentation
 
 .. c:function:: void  glm_vec_copy(vec3 a, vec3 dest)
 
-     copy all members of [a] to [dest]
+    copy all members of [a] to [dest]
 
     Parameters:
       | *[in]*  **a**     source