From b2679d32f8e2893f063518bb5d3057f28d7f1b99 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20Vondru=C5=A1?= <mosra@centrum.cz>
Date: Wed, 26 Sep 2012 00:30:05 +0200
Subject: [PATCH] MeshTools: added transform() function.

In the future it will use multithreading/GPU transform feedback for
large arrays.
---
 src/MeshTools/CMakeLists.txt |  1 +
 src/MeshTools/Transform.h    | 44 ++++++++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+)
 create mode 100644 src/MeshTools/Transform.h

diff --git a/src/MeshTools/CMakeLists.txt b/src/MeshTools/CMakeLists.txt
index 095431bf7..4fb800958 100644
--- a/src/MeshTools/CMakeLists.txt
+++ b/src/MeshTools/CMakeLists.txt
@@ -11,6 +11,7 @@ set(MagnumMeshTools_HEADERS
     Interleave.h
     Subdivide.h
     Tipsify.h
+    Transform.h
 
     magnumMeshToolsVisibility.h)
 add_library(MagnumMeshToolsObjects OBJECT ${MagnumMeshTools_SRCS})
diff --git a/src/MeshTools/Transform.h b/src/MeshTools/Transform.h
new file mode 100644
index 000000000..7e09e59ae
--- /dev/null
+++ b/src/MeshTools/Transform.h
@@ -0,0 +1,44 @@
+#ifndef Magnum_MeshTools_Transform_h
+#define Magnum_MeshTools_Transform_h
+/*
+    Copyright © 2010, 2011, 2012 Vladimír Vondruš <mosra@centrum.cz>
+
+    This file is part of Magnum.
+
+    Magnum is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License version 3
+    only, as published by the Free Software Foundation.
+
+    Magnum is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+    GNU Lesser General Public License version 3 for more details.
+*/
+
+/** @file
+ * @brief Function Magnum::MeshTools::transform()
+ */
+
+#include "Math/Matrix.h"
+
+namespace Magnum { namespace MeshTools {
+
+/**
+@brief Transform vertices using given matrix
+
+Usable for mesh transformations that would otherwise negatively affect
+dependent objects, such as (uneven) scaling. Example usage:
+
+@code
+std::vector<Point3D> vertices;
+MeshTools::transform(Matrix4::scaling({2.0f, 0.5f, 0.0f}), vertices);
+@endcode
+*/
+template<size_t size, class T, class U> inline void transform(const Math::Matrix<size, T>& matrix, U& vertices) {
+    for(Math::Vector<size, T>& vertex: vertices)
+        vertex = matrix*vertex;
+}
+
+}}
+
+#endif