mirror of https://github.com/mosra/magnum.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
47 lines
1.9 KiB
47 lines
1.9 KiB
/* |
|
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. |
|
*/ |
|
|
|
#include "GenerateFlatNormals.h" |
|
|
|
#include "Math/Vector3.h" |
|
#include "MeshTools/Clean.h" |
|
|
|
namespace Magnum { namespace MeshTools { |
|
|
|
std::tuple<std::vector<UnsignedInt>, std::vector<Vector3>> generateFlatNormals(const std::vector<UnsignedInt>& indices, const std::vector<Vector3>& positions) { |
|
CORRADE_ASSERT(!(indices.size()%3), "MeshTools::generateFlatNormals(): index count is not divisible by 3!", (std::tuple<std::vector<UnsignedInt>, std::vector<Vector3>>())); |
|
|
|
/* Create normal for every triangle (assuming counterclockwise winding) */ |
|
std::vector<UnsignedInt> normalIndices; |
|
normalIndices.reserve(indices.size()); |
|
std::vector<Vector3> normals; |
|
normals.reserve(indices.size()/3); |
|
for(std::size_t i = 0; i != indices.size(); i += 3) { |
|
Vector3 normal = Vector3::cross(positions[indices[i+2]]-positions[indices[i+1]], |
|
positions[indices[i]]-positions[indices[i+1]]).normalized(); |
|
|
|
/* Use the same normal for all three vertices of the face */ |
|
normalIndices.push_back(normals.size()); |
|
normalIndices.push_back(normals.size()); |
|
normalIndices.push_back(normals.size()); |
|
normals.push_back(normal); |
|
} |
|
|
|
/* Clean duplicate normals and return */ |
|
MeshTools::clean(normalIndices, normals); |
|
return std::make_tuple(normalIndices, normals); |
|
} |
|
|
|
}}
|
|
|