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diff --git a/include/cglm/clipspace/persp_lh_zo.h b/include/cglm/clipspace/persp_lh_zo.h
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+++ b/include/cglm/clipspace/persp_lh_zo.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
+ */
+
+/*
+ Functions:
+   CGLM_INLINE void glm_frustum_lh_zo(float left,    float right,
+                                      float bottom,  float top,
+                                      float nearZ, float farZ,
+                                      mat4  dest)
+   CGLM_INLINE void glm_perspective_lh_zo(float fovy,
+                                          float aspect,
+                                          float nearZ,
+                                          float farZ,
+                                          mat4  dest)
+   CGLM_INLINE void glm_perspective_default_lh_zo(float aspect, mat4 dest)
+   CGLM_INLINE void glm_perspective_resize_lh_zo(float aspect, mat4 proj)
+   CGLM_INLINE void glm_persp_move_far_lh_zo(mat4 proj,
+                                             float deltaFar)
+   CGLM_INLINE void glm_persp_decomp_lh_zo(mat4 proj,
+                                           float * __restrict nearZ,
+                                           float * __restrict farZ,
+                                           float * __restrict top,
+                                           float * __restrict bottom,
+                                           float * __restrict left,
+                                           float * __restrict right)
+  CGLM_INLINE void glm_persp_decompv_lh_zo(mat4 proj,
+                                           float dest[6])
+  CGLM_INLINE void glm_persp_decomp_x_lh_zo(mat4 proj,
+                                            float * __restrict left,
+                                            float * __restrict right)
+  CGLM_INLINE void glm_persp_decomp_y_lh_zo(mat4 proj,
+                                            float * __restrict top,
+                                            float * __restrict bottom)
+  CGLM_INLINE void glm_persp_decomp_z_lh_zo(mat4 proj,
+                                            float * __restrict nearZ,
+                                            float * __restrict farZ)
+  CGLM_INLINE void glm_persp_decomp_far_lh_zo(mat4 proj, float * __restrict farZ)
+  CGLM_INLINE void glm_persp_decomp_near_lh_zo(mat4 proj, float * __restrict nearZ)
+  CGLM_INLINE void glm_persp_sizes_lh_zo(mat4 proj, float fovy, vec4 dest)
+ */
+
+#ifndef cglm_persp_lh_zo_h
+#define cglm_persp_lh_zo_h
+
+#include "../common.h"
+#include "persp.h"
+
+/*!
+ * @brief set up perspective peprojection matrix with a left-hand coordinate
+ *        system and a clip-space of [0, 1].
+ *
+ * @param[in]  left    viewport.left
+ * @param[in]  right   viewport.right
+ * @param[in]  bottom  viewport.bottom
+ * @param[in]  top     viewport.top
+ * @param[in]  nearZ   near clipping plane
+ * @param[in]  farZ    far clipping plane
+ * @param[out] dest    result matrix
+ */
+CGLM_INLINE
+void
+glm_frustum_lh_zo(float left,    float right,
+                  float bottom,  float top,
+                  float nearZ, float farZ,
+                  mat4  dest) {
+  float rl, tb, fn, nv;
+
+  glm_mat4_zero(dest);
+
+  rl = 1.0f / (right  - left);
+  tb = 1.0f / (top    - bottom);
+  fn =-1.0f / (farZ - nearZ);
+  nv = 2.0f * nearZ;
+
+  dest[0][0] = nv * rl;
+  dest[1][1] = nv * tb;
+  dest[2][0] = (right  + left)    * rl;
+  dest[2][1] = (top    + bottom)  * tb;
+  dest[2][2] =-farZ * fn;
+  dest[2][3] = 1.0f;
+  dest[3][2] = farZ * nearZ * fn;
+}
+
+/*!
+ * @brief set up perspective projection matrix with a left-hand coordinate
+ * system and a clip-space of [0, 1].
+ *
+ * @param[in]  fovy    field of view angle
+ * @param[in]  aspect  aspect ratio ( width / height )
+ * @param[in]  nearZ   near clipping plane
+ * @param[in]  farZ    far clipping planes
+ * @param[out] dest    result matrix
+ */
+CGLM_INLINE
+void
+glm_perspective_lh_zo(float fovy,
+                      float aspect,
+                      float nearZ,
+                      float farZ,
+                      mat4  dest) {
+  float f, fn;
+
+  glm_mat4_zero(dest);
+
+  f  = 1.0f / tanf(fovy * 0.5f);
+  fn = 1.0f / (nearZ - farZ);
+
+  dest[0][0] = f / aspect;
+  dest[1][1] = f;
+  dest[2][2] =-farZ * fn;
+  dest[2][3] = 1.0f;
+  dest[3][2] = nearZ * farZ * fn;
+}
+
+/*!
+ * @brief extend perspective projection matrix's far distance with a
+ *        left-hand coordinate system and a clip-space with depth values
+ *        from zero to one.
+ *
+ * this function does not guarantee far >= near, be aware of that!
+ *
+ * @param[in, out] proj      projection matrix to extend
+ * @param[in]      deltaFar  distance from existing far (negative to shink)
+ */
+CGLM_INLINE
+void
+glm_persp_move_far_lh_zo(mat4 proj, float deltaFar) {
+  float fn, farZ, nearZ, p22, p32;
+
+  p22        = -proj[2][2];
+  p32        = proj[3][2];
+
+  nearZ    = p32 / p22;
+  farZ     = p32 / (p22 + 1.0f) + deltaFar;
+  fn         = 1.0f / (nearZ - farZ);
+
+  proj[2][2] = -farZ * fn;
+  proj[3][2] = nearZ * farZ * fn;
+}
+
+/*!
+ * @brief set up perspective projection matrix with default near/far
+ *        and angle values with a left-hand coordinate system and a 
+ *        clip-space of [0, 1].
+ *
+ * @param[in]  aspect aspect ratio ( width / height )
+ * @param[out] dest   result matrix
+ */
+CGLM_INLINE
+void
+glm_perspective_default_lh_zo(float aspect, mat4 dest) {
+  glm_perspective_lh_zo(GLM_PI_4f, aspect, 0.01f, 100.0f, dest);
+}
+
+/*!
+ * @brief resize perspective matrix by aspect ratio ( width / height )
+ *        this makes very easy to resize proj matrix when window /viewport
+ *        reized
+ *
+ * @param[in]      aspect aspect ratio ( width / height )
+ * @param[in, out] proj   perspective projection matrix
+ */
+CGLM_INLINE
+void
+glm_perspective_resize_lh_zo(float aspect, mat4 proj) {
+  if (proj[0][0] == 0.0f)
+    return;
+
+  proj[0][0] = proj[1][1] / aspect;
+}
+
+/*!
+ * @brief decomposes frustum values of perspective projection
+ *        with angle values with a left-hand coordinate system and a 
+ *        clip-space of [0, 1].
+ *
+ * @param[in]  proj    perspective projection matrix
+ * @param[out] nearZ   near
+ * @param[out] farZ    far
+ * @param[out] top     top
+ * @param[out] bottom  bottom
+ * @param[out] left    left
+ * @param[out] right   right
+ */
+CGLM_INLINE
+void
+glm_persp_decomp_lh_zo(mat4 proj,
+                    float * __restrict nearZ, float * __restrict farZ,
+                    float * __restrict top,     float * __restrict bottom,
+                    float * __restrict left,    float * __restrict right) {
+  float m00, m11, m20, m21, m22, m32, n, f;
+  float n_m11, n_m00;
+
+  m00 = proj[0][0];
+  m11 = proj[1][1];
+  m20 = proj[2][0];
+  m21 = proj[2][1];
+  m22 =-proj[2][2];
+  m32 = proj[3][2];
+
+  n = m32 / m22;
+  f = m32 / (m22 + 1.0f);
+
+  n_m11 = n / m11;
+  n_m00 = n / m00;
+
+  *nearZ = n;
+  *farZ  = f;
+  *bottom  = n_m11 * (m21 - 1.0f);
+  *top     = n_m11 * (m21 + 1.0f);
+  *left    = n_m00 * (m20 - 1.0f);
+  *right   = n_m00 * (m20 + 1.0f);
+}
+
+/*!
+ * @brief decomposes frustum values of perspective projection
+ *        with angle values with a left-hand coordinate system and a 
+ *        clip-space of [0, 1].
+ *        this makes easy to get all values at once
+ *
+ * @param[in]  proj   perspective projection matrix
+ * @param[out] dest   array
+ */
+CGLM_INLINE
+void
+glm_persp_decompv_lh_zo(mat4 proj, float dest[6]) {
+  glm_persp_decomp_lh_zo(proj, &dest[0], &dest[1], &dest[2],
+                               &dest[3], &dest[4], &dest[5]);
+}
+
+/*!
+ * @brief decomposes left and right values of perspective projection (ZO).
+ *        x stands for x axis (left / right axis)
+ *
+ * @param[in]  proj  perspective projection matrix
+ * @param[out] left  left
+ * @param[out] right right
+ */
+CGLM_INLINE
+void
+glm_persp_decomp_x_lh_zo(mat4 proj,
+                         float * __restrict left,
+                         float * __restrict right) {
+  float nearZ, m20, m00;
+
+  m00 = proj[0][0];
+  m20 = proj[2][0];
+
+  nearZ = proj[3][2] / (proj[3][3]);
+  *left   = nearZ * (m20 - 1.0f) / m00;
+  *right  = nearZ * (m20 + 1.0f) / m00;
+}
+
+/*!
+ * @brief decomposes top and bottom values of perspective projection
+ *        with angle values with a left-hand coordinate system and a 
+ *        clip-space of [0, 1].
+ *        y stands for y axis (top / bottom axis)
+ *
+ * @param[in]  proj   perspective projection matrix
+ * @param[out] top    top
+ * @param[out] bottom bottom
+ */
+CGLM_INLINE
+void
+glm_persp_decomp_y_lh_zo(mat4 proj,
+                         float * __restrict top,
+                         float * __restrict bottom) {
+  float nearZ, m21, m11;
+
+  m21 = proj[2][1];
+  m11 = proj[1][1];
+
+  nearZ = proj[3][2] / (proj[3][3]);
+  *bottom = nearZ * (m21 - 1) / m11;
+  *top    = nearZ * (m21 + 1) / m11;
+}
+
+/*!
+ * @brief decomposes near and far values of perspective projection
+ *        with angle values with a left-hand coordinate system and a 
+ *        clip-space of [0, 1].
+ *        z stands for z axis (near / far axis)
+ *
+ * @param[in]  proj    perspective projection matrix
+ * @param[out] nearZ   near
+ * @param[out] farZ    far
+ */
+CGLM_INLINE
+void
+glm_persp_decomp_z_lh_zo(mat4 proj,
+                         float * __restrict nearZ,
+                         float * __restrict farZ) {
+  float m32, m22;
+
+  m32 = proj[3][2];
+  m22 = -proj[2][2];
+
+  *nearZ = m32 / m22;
+  *farZ  = m32 / (m22 + 1.0f);
+}
+
+/*!
+ * @brief decomposes far value of perspective projection
+ *        with angle values with a left-hand coordinate system and a 
+ *        clip-space of [0, 1].
+ *
+ * @param[in]  proj   perspective projection matrix
+ * @param[out] farZ   far
+ */
+CGLM_INLINE
+void
+glm_persp_decomp_far_lh_zo(mat4 proj, float * __restrict farZ) {
+  *farZ = proj[3][2] / (-proj[2][2] + 1.0f);
+}
+
+/*!
+ * @brief decomposes near value of perspective projection
+ *        with angle values with a left-hand coordinate system and a 
+ *        clip-space of [0, 1].
+ *
+ * @param[in]  proj    perspective projection matrix
+ * @param[out] nearZ   near
+ */
+CGLM_INLINE
+void
+glm_persp_decomp_near_lh_zo(mat4 proj, float * __restrict nearZ) {
+  *nearZ = proj[3][2] / -proj[2][2];
+}
+
+/*!
+ * @brief returns sizes of near and far planes of perspective projection
+ *        with a left-hand coordinate system and a
+ *        clip-space of [0, 1].
+ *
+ * @param[in]  proj perspective projection matrix
+ * @param[in]  fovy fovy (see brief)
+ * @param[out] dest sizes order: [Wnear, Hnear, Wfar, Hfar]
+ */
+CGLM_INLINE
+void
+glm_persp_sizes_lh_zo(mat4 proj, float fovy, vec4 dest) {
+  float t, a, nearZ, farZ;
+
+  t = 2.0f * tanf(fovy * 0.5f);
+  a = glm_persp_aspect(proj);
+
+  glm_persp_decomp_z_lh_zo(proj, &nearZ, &farZ);
+
+  dest[1]  = t * nearZ;
+  dest[3]  = t * farZ;
+  dest[0]  = a * dest[1];
+  dest[2]  = a * dest[3];
+}
+
+/*!
+ * @brief returns field of view angle along the Y-axis (in radians)
+ *        with a left-hand coordinate system and a clip-space of [0, 1].
+ *
+ * if you need to degrees, use glm_deg to convert it or use this:
+ * fovy_deg = glm_deg(glm_persp_fovy(projMatrix))
+ *
+ * @param[in] proj perspective projection matrix
+ */
+CGLM_INLINE
+float
+glm_persp_fovy_lh_zo(mat4 proj) {
+  return glm_persp_fovy(proj);
+}
+
+/*!
+ * @brief returns aspect ratio of perspective projection
+ *        with a left-hand coordinate system and a clip-space of [0, 1].
+ *
+ * @param[in] proj perspective projection matrix
+ */
+CGLM_INLINE
+float
+glm_persp_aspect_lh_zo(mat4 proj) {
+  return glm_persp_aspect(proj);
+}
+
+#endif /*cglm_persp_lh_zo_h*/