From 7960e832debea82d0428fef2c5b58cca04b3c803 Mon Sep 17 00:00:00 2001
From: Thompson Lee <tom.mai78101@gmail.com>
Date: Sun, 11 Sep 2016 17:40:10 -0400
Subject: [PATCH] Added Mtx_Diagonal(). (#27)

---
 include/c3d/maths.h         | 32 ++++++++++++++++++++++++++------
 source/maths/mtx_identity.c | 10 ----------
 2 files changed, 26 insertions(+), 16 deletions(-)
 delete mode 100644 source/maths/mtx_identity.c

diff --git a/include/c3d/maths.h b/include/c3d/maths.h
index 215a4ce..123064d 100644
--- a/include/c3d/maths.h
+++ b/include/c3d/maths.h
@@ -283,12 +283,6 @@ static inline void Mtx_Copy(C3D_Mtx* out, const C3D_Mtx* in)
 	*out = *in;
 }
 
-/**
- * @brief Identity matrix
- * @param[out] out Matrix to fill
- */
-void Mtx_Identity(C3D_Mtx* out);
-
 /**
  * @brief Multiply two matrices
  * @param[out] out Output matrix
@@ -495,6 +489,32 @@ void Mtx_LookAt(C3D_Mtx* out, C3D_FVec cameraPosition, C3D_FVec cameraTarget, C3
  *@param[in,out] out     Output matrix.
  */
 void Mtx_Transpose(C3D_Mtx* out);
+
+/**
+ * @brief Creates a matrix with the diagonal using the given parameters.
+ * @param[out]  out    Output matrix.
+ * @param[in]   x      The X component.
+ * @param[in]   y      The Y component.
+ * @param[in]   z      The Z component.
+ * @param[in]   w      The W component.
+ */
+static inline void Mtx_Diagonal(C3D_Mtx* out, float x, float y, float z, float w)
+{
+	Mtx_Zeros(out);
+	out->r[0].x = x;
+	out->r[1].y = y;
+	out->r[2].z = z;
+	out->r[3].w = w;
+}
+
+/**
+ * @brief Identity matrix
+ * @param[out] out Matrix to fill
+ */
+static inline void Mtx_Identity(C3D_Mtx* out)
+{
+	Mtx_Diagonal(out, 1.0f, 1.0f, 1.0f, 1.0f);
+}
 ///@}
 
 ///@name Quaternion Math
diff --git a/source/maths/mtx_identity.c b/source/maths/mtx_identity.c
deleted file mode 100644
index 2ce7461..0000000
--- a/source/maths/mtx_identity.c
+++ /dev/null
@@ -1,10 +0,0 @@
-#include <c3d/maths.h>
-
-void Mtx_Identity(C3D_Mtx* out)
-{
-	// http://www.wolframalpha.com/input/?i={{1,0,0,0},{0,1,0,0},{0,0,1,0},{0,0,0,1}}
-	int i;
-	for (i = 0; i < 16; ++i)
-		out->m[i] = 0.0f;
-	out->r[0].x = out->r[1].y = out->r[2].z = out->r[3].w = 1.0f;
-}