mr-math
Lightweight and high-performance linear algebra library for 3d graphics
Comparison
| Library | Matrix Multiplication (ns) | Vector normalization (ns) | Scalar triple products (ns) | |————–|—————————-|—————————|—————————–| | mr. Math | 4 | 2 | 6.5 | | DirectXMath | 4.8 | 4.3 | 2.3 | | glm | 5.7 | 3.3 | 1.6 | | cglm | 6.2 | 14.6 | 2.2 | | lin | 5.7 | 3.3 | 2.3 |
Usage
Vectors
Initialization
// alias for mr::Vec<float, 3>
mr::Vec3f v1 {1, 0, 0};
mr::Vec3f v2 {0, 1, 0};
Operations
// cross product
std::cout << v1 % v2 << std::endl; // output: (0, 0, 1)
// dot product
std::cout << v1 & v2 << std::endl; // output: 0
// returns normalized copy
mr::Vec3f v3 {2, 0, 0};
mr::Vec3f v4 = v3.normalized();
std::cout << v3 << " " << v4 << std::endl; // output: (2, 0, 0) (1, 0, 0)
// normalizes in place, returns mutable reference
mr::Vec3f v3 {2, 0, 0};
mr::Vec3f v4 = v3.normalize();
std::cout << v3 << " " << v4 << std::endl; // output: (1, 0, 0) (1, 0, 0)
mr::Vec3f v5 {3, 4, 0};
// calculates length (slowest)
float l = v5.length();
std::cout << l << std::endl; // output: 5
// calculates 1/length (faster)
float l = v5.inversed_length();
std::cout << l << std::endl; // output: 0.2
// calculates squared length (fastest)
float l = v5.length2();
std::cout << l << std::endl; // output: 25
// etc (+ - [0..N-1])
Matrices
Initialization
/// alias for mr::Matr<float, 4>
mr::Matr4f m1 {
mr::Matr4f::Row_t{1, 0, 0, 0},
mr::Matr4f::Row_t{1, 0, 0, 0},
mr::Matr4f::Row_t{1, 0, 0, 0},
mr::Matr4f::Row_t{1, 0, 0, 0},
};
mr::Matr<float, 4> m2 {
mr::Matr4f::Row_t{1, 2, 3, 4},
mr::Matr4f::Row_t{1, 2, 3, 4},
mr::Matr4f::Row_t{1, 2, 3, 4},
mr::Matr4f::Row_t{1, 2, 3, 4},
};
Operations
// calculate determinant
float d1 = m1.determinant();
std::cout << d1 << std::endl; // output: 0
// alternative
float d1 = !m1;
std::cout << d1 << std::endl; // output: 0
// returns transposed copy
m1.transposed();
// transposes in place
m1.transpose();
mr::Matr4f m4 {
mr::Matr4f::Row_t{2, 0, 0, 0},
mr::Matr4f::Row_t{0, 2, 0, 0},
mr::Matr4f::Row_t{0, 0, 2, 0},
mr::Matr4f::Row_t{0, 0, 0, 2}
};
// returns inversed copy
mr::Matr4f m5 = m4.inversed();
std::cout << m5 << std::endl;
// output:
// (0.5, 0, 0, 0)
// (0, 0.5, 0, 0)
// (0, 0, 0.5, 0)
// (0, 0, 0, 0.5)
// inverses in place
mr::Matr4f m6 = m4.inverse();
// m4 is equal to m5 at this point
// etc (+ - * [][] ...)
Installation
Using CPM.cmake:
CPMAddPackage(
NAME mr-math
GITHUB_REPOSITORY 4J-company/mr-math
VERSION 1.0.0
)
Manually:
Clone to your project subdirectory
git clone https://github.com/4J-company/mr-math
Link mr-math to your project
add_subdirectory(mr-math)
target_link_libraries(<your-project>
PUBLIC/INTERFACE/PRIVATE
mr-math)