diff --git a/libretro-common/gfx/math/matrix_4x4.c b/libretro-common/gfx/math/matrix_4x4.c
index 9c27ba6419..c132c5730f 100644
--- a/libretro-common/gfx/math/matrix_4x4.c
+++ b/libretro-common/gfx/math/matrix_4x4.c
@@ -24,6 +24,9 @@
 #include <string.h>
 #include <math.h>
 
+/*
+ * Sets mat to an identity matrix
+ */
 void matrix_4x4_identity(math_matrix_4x4 *mat)
 {
    unsigned i;
@@ -33,6 +36,9 @@ void matrix_4x4_identity(math_matrix_4x4 *mat)
       MAT_ELEM_4X4(*mat, i, i) = 1.0f;
 }
 
+/*
+ * Sets out to the transposed matrix of in
+ */
 void matrix_4x4_transpose(math_matrix_4x4 *out, const math_matrix_4x4 *in)
 {
    unsigned i, j;
@@ -45,6 +51,9 @@ void matrix_4x4_transpose(math_matrix_4x4 *out, const math_matrix_4x4 *in)
    *out = mat;
 }
 
+/*
+ * Builds an X-axis rotation matrix
+ */
 void matrix_4x4_rotate_x(math_matrix_4x4 *mat, float rad)
 {
    float cosine = cosf(rad);
@@ -58,6 +67,10 @@ void matrix_4x4_rotate_x(math_matrix_4x4 *mat, float rad)
    MAT_ELEM_4X4(*mat, 2, 1) = sine;
 }
 
+/*
+ * Builds a rotation matrix using the 
+ * rotation around the Y-axis.
+ */
 void matrix_4x4_rotate_y(math_matrix_4x4 *mat, float rad)
 {
    float cosine = cosf(rad);
@@ -71,6 +84,10 @@ void matrix_4x4_rotate_y(math_matrix_4x4 *mat, float rad)
    MAT_ELEM_4X4(*mat, 2, 0) = sine;
 }
 
+/*
+ * Builds a rotation matrix using the 
+ * rotation around the Z-axis.
+ */
 void matrix_4x4_rotate_z(math_matrix_4x4 *mat, float rad)
 {
    float cosine = cosf(rad);
@@ -84,6 +101,9 @@ void matrix_4x4_rotate_z(math_matrix_4x4 *mat, float rad)
    MAT_ELEM_4X4(*mat, 1, 0) = sine;
 }
 
+/*
+ * Creates an orthographic projection matrix.
+ */
 void matrix_4x4_ortho(math_matrix_4x4 *mat,
       float left, float right,
       float bottom, float top,
@@ -115,6 +135,11 @@ void matrix_4x4_scale(math_matrix_4x4 *out, float x, float y,
    MAT_ELEM_4X4(*out, 3, 3) = 1.0f;
 }
 
+/*
+ * Builds a translation matrix. All other elements in 
+ * the matrix will be set to zero except for the
+ * diagonal which is set to 1.0
+ */
 void matrix_4x4_translate(math_matrix_4x4 *out, float x,
       float y, float z)
 {
@@ -124,6 +149,9 @@ void matrix_4x4_translate(math_matrix_4x4 *out, float x,
    MAT_ELEM_4X4(*out, 2, 3) = z;
 }
 
+/*
+ * Creates a perspective projection matrix.
+ */
 void matrix_4x4_projection(math_matrix_4x4 *out, float znear,
       float zfar)
 {
@@ -135,6 +163,9 @@ void matrix_4x4_projection(math_matrix_4x4 *out, float znear,
    MAT_ELEM_4X4(*out, 3, 2) = -1.0f;
 }
 
+/*
+ * Multiplies a with b, stores the result in out
+ */
 void matrix_4x4_multiply(
       math_matrix_4x4 *out,
       const math_matrix_4x4 *a,