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| author | Nao Pross <naopross@thearcway.org> | 2018-12-10 15:10:55 +0100 |
|---|---|---|
| committer | Nao Pross <naopross@thearcway.org> | 2018-12-10 15:10:55 +0100 |
| commit | c2ec583c30cc95dd681dbb0c9fc5a46572913e22 (patch) | |
| tree | 973ded7a18a2e63e4998ac30d384478f0702af20 | |
| parent | Implement cross product for vec2 and vec3 (diff) | |
| download | cplusplus-c2ec583c30cc95dd681dbb0c9fc5a46572913e22.tar.gz cplusplus-c2ec583c30cc95dd681dbb0c9fc5a46572913e22.zip | |
Update makefile ad update basic_vec to allow abstract algebraic structures
Unfortunately this requires C++17 as `static constexpr` members
have an undefined behaviour before this version.
| -rw-r--r-- | vector/makefile | 4 | ||||
| -rw-r--r-- | vector/vector.cpp | 13 |
2 files changed, 11 insertions, 6 deletions
diff --git a/vector/makefile b/vector/makefile index 1303aa3..31136ea 100644 --- a/vector/makefile +++ b/vector/makefile @@ -2,8 +2,8 @@ CC := gcc CARGS := -Wall -Werror -I. LDARGS := -lm -CPPC := g++ -CPPARGS := -Wall -I. +CPPC := g++-8 +CPPARGS := -Wall -I. -std=c++17 all: vector.pdf c_build/vector cpp_build/vector diff --git a/vector/vector.cpp b/vector/vector.cpp index 9e0ca6c..d5f0c36 100644 --- a/vector/vector.cpp +++ b/vector/vector.cpp @@ -6,10 +6,15 @@ #include <initializer_list> #include <algorithm> + template<typename T, std::size_t d> struct basic_vec : public std::array<T, d> { static constexpr std::size_t dimensions = d; + static constexpr T null_element = static_cast<T>(0); + static constexpr T unit_element = static_cast<T>(1); + static constexpr T unit_additive_inverse_element = static_cast<T>(-1); + basic_vec(); basic_vec(const std::initializer_list<T> l); template<std::size_t n> basic_vec(const basic_vec<T, n>& other); @@ -19,7 +24,7 @@ struct basic_vec : public std::array<T, d> { template<typename T, std::size_t d> basic_vec<T, d>::basic_vec() : std::array<T, d>() { - this->fill(static_cast<T>(0)); + this->fill(basic_vec<T,d>::null_element); } template<typename T, std::size_t d> @@ -44,7 +49,7 @@ basic_vec<T, d>::basic_vec(const basic_vec<T, n>& other) { template<typename T, std::size_t d> T basic_vec<T, d>::length() const { - T res = static_cast<T>(0); + T res = basic_vec<T, d>::null_element; for (const T& val : *this) { res += val * val; } @@ -77,12 +82,12 @@ basic_vec<T, d> operator*(const T& rhs, const basic_vec<T, d>& lhs) { template<typename T, std::size_t d> basic_vec<T, d> operator-(const basic_vec<T, d>& rhs, const basic_vec<T, d>& lhs) { - return rhs + static_cast<T>(-1) * lhs; + return rhs + basic_vec<T, d>::unit_additive_inverse_element * lhs; } template<typename T, std::size_t d> T operator*(const basic_vec<T, d>& rhs, const basic_vec<T, d>& lhs) { - T res = static_cast<T>(0); + T res = basic_vec<T, d>::null_element; for (std::size_t i = 0; i < d; i++) { res += rhs[i] * lhs[i]; } |