From eb2b1eafb32e4a4ee27016ee590ff349510089a1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gonzalo=20Garramu=C3=B1o?= <ggarra13@gmail.com>
Date: Tue, 21 May 2024 18:18:48 -0300
Subject: [PATCH] Fixed matrix calculation. (#138)

---
 lib/tlCore/MatrixInline.h | 24 ++++++++++--------------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/lib/tlCore/MatrixInline.h b/lib/tlCore/MatrixInline.h
index 0efcb70be..ffa7a93a3 100644
--- a/lib/tlCore/MatrixInline.h
+++ b/lib/tlCore/MatrixInline.h
@@ -240,13 +240,12 @@ namespace tl
         inline Vector3<T> operator * (const Matrix4x4<T>& a, const Vector3<T>& v)
         {
             Vector3<T> out;
-            for (int i = 0; i < 3; ++i)
-            {
-                for (int j = 0; j < 3; ++j)
-                {
-                    out[i] += a.e[i * 4 + j] * v[j];
-                }
-            }
+            T x = T (v[0] * a.e[0] + v[1] * a.e[4] + v[2] * a.e[8]  + a.e[12]);
+            T y = T (v[0] * a.e[1] + v[1] * a.e[5] + v[2] * a.e[9]  + a.e[13]);
+            T z = T (v[0] * a.e[2] + v[1] * a.e[6] + v[2] * a.e[10] + a.e[14]);
+            T w = T (v[0] * a.e[3] + v[1] * a.e[7] + v[2] * a.e[11] + a.e[15]);
+
+            out = Vector3<T> (x / w, y / w, z / w);
             return out;
         }
 
@@ -254,13 +253,10 @@ namespace tl
         inline Vector4<T> operator * (const Matrix4x4<T>& a, const Vector4<T>& v)
         {
             Vector4<T> out;
-            for (int i = 0; i < 4; ++i)
-            {
-                for (int j = 0; j < 4; ++j)
-                {
-                    out[i] += a.e[i * 4 + j] * v[j];
-                }
-            }
+            out.x = T (v[0] * a.e[0] + v[1] * a.e[4] + v[2] * a.e[8]  + v[3] * a.e[12]);
+            out.y = T (v[0] * a.e[1] + v[1] * a.e[5] + v[2] * a.e[9]  + v[3] * a.e[13]);
+            out.z = T (v[0] * a.e[2] + v[1] * a.e[6] + v[2] * a.e[10] + v[3] * a.e[14]);
+            out.w = T (v[0] * a.e[3] + v[1] * a.e[7] + v[2] * a.e[11] + v[3] * a.e[15]);
             return out;
         }
     };