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stupidsimcpp/util/vecmat/mat4.hpp
2025-12-31 10:49:52 -05:00

324 lines
11 KiB
C++

#ifndef MAT4_HPP
#define MAT4_HPP
#include "../vectorlogic/vec3.hpp"
#include "../vectorlogic/vec4.hpp"
#include "../ray3.hpp"
#include <array>
#include <cmath>
template<typename T>
class Mat4 {
public:
union {
struct {
T m00, m01, m02, m03,
m10, m11, m12, m13,
m20, m21, m22, m23,
m30, m31, m32, m33;
};
T data[16];
T m[4][4];
};
// Constructors
Mat4() : m00(1), m01(0), m02(0), m03(0),
m10(0), m11(1), m12(0), m13(0),
m20(0), m21(0), m22(1), m23(0),
m30(0), m31(0), m32(0), m33(1) {}
Mat4(T scalar) : m00(scalar), m01(scalar), m02(scalar), m03(scalar),
m10(scalar), m11(scalar), m12(scalar), m13(scalar),
m20(scalar), m21(scalar), m22(scalar), m23(scalar),
m30(scalar), m31(scalar), m32(scalar), m33(scalar) {}
Mat4(T m00, T m01, T m02, T m03,
T m10, T m11, T m12, T m13,
T m20, T m21, T m22, T m23,
T m30, T m31, T m32, T m33) :
m00(m00), m01(m01), m02(m02), m03(m03),
m10(m10), m11(m11), m12(m12), m13(m13),
m20(m20), m21(m21), m22(m22), m23(m23),
m30(m30), m31(m31), m32(m32), m33(m33) {}
// Identity matrix
static Mat4<T> identity() {
return Mat4<T>(1, 0, 0, 0,
0, 1, 0, 0,
0, 0, 1, 0,
0, 0, 0, 1);
}
// Zero matrix
static Mat4 zero() { return Mat4(0); }
// Translation matrix
static Mat4 translation(const Vec3<T>& translation) {
return Mat4(1, 0, 0, translation.x,
0, 1, 0, translation.y,
0, 0, 1, translation.z,
0, 0, 0, 1);
}
// Rotation matrices
static Mat4 rotationX(T angle) {
T cosA = std::cos(angle);
T sinA = std::sin(angle);
return Mat4(1, 0, 0, 0,
0, cosA, -sinA, 0,
0, sinA, cosA, 0,
0, 0, 0, 1);
}
static Mat4 rotationY(T angle) {
T cosA = std::cos(angle);
T sinA = std::sin(angle);
return Mat4(cosA, 0, sinA, 0,
0, 1, 0, 0,
-sinA, 0, cosA, 0,
0, 0, 0, 1);
}
static Mat4 rotationZ(T angle) {
T cosA = std::cos(angle);
T sinA = std::sin(angle);
return Mat4(cosA, -sinA, 0, 0,
sinA, cosA, 0, 0,
0, 0, 1, 0,
0, 0, 0, 1);
}
// Scaling matrix
static Mat4 scaling(const Vec3<T>& scale) {
return Mat4(scale.x, 0, 0, 0,
0, scale.y, 0, 0,
0, 0, scale.z, 0,
0, 0, 0, 1);
}
// Perspective projection matrix
static Mat4 perspective(T fov, T aspect, T near, T far) {
T tanHalfFov = std::tan(fov / static_cast<T>(2));
T range = near - far;
return Mat4(static_cast<T>(1) / (aspect * tanHalfFov), 0, 0, 0,
0, static_cast<T>(1) / tanHalfFov, 0, 0,
0, 0, (-near - far) / range, static_cast<T>(2) * far * near / range,
0, 0, 1, 0);
}
// Orthographic projection matrix
static Mat4 orthographic(T left, T right, T bottom, T top, T near, T far) {
return Mat4(static_cast<T>(2) / (right - left), 0, 0, -(right + left) / (right - left),
0, static_cast<T>(2) / (top - bottom), 0, -(top + bottom) / (top - bottom),
0, 0, -static_cast<T>(2) / (far - near), -(far + near) / (far - near),
0, 0, 0, 1);
}
// LookAt matrix (view matrix)
static Mat4 lookAt(const Vec3<T>& eye, const Vec3<T>& target, const Vec3<T>& up) {
Vec3<T> z = (eye - target).normalized();
Vec3<T> x = up.cross(z).normalized();
Vec3<T> y = z.cross(x);
return Mat4(x.x, x.y, x.z, -x.dot(eye),
y.x, y.y, y.z, -y.dot(eye),
z.x, z.y, z.z, -z.dot(eye),
0, 0, 0, 1);
}
// Arithmetic operations
Mat4 operator+(const Mat4& other) const {
Mat4 result;
for (int i = 0; i < 16; ++i) {
result.data[i] = data[i] + other.data[i];
}
return result;
}
Mat4 operator-(const Mat4& other) const {
Mat4 result;
for (int i = 0; i < 16; ++i) {
result.data[i] = data[i] - other.data[i];
}
return result;
}
Mat4 operator*(const Mat4& other) const {
Mat4 result;
for (int i = 0; i < 4; ++i) {
for (int j = 0; j < 4; ++j) {
result.m[i][j] = 0;
for (int k = 0; k < 4; ++k) {
result.m[i][j] += m[i][k] * other.m[k][j];
}
}
}
return result;
}
Mat4 operator*(T scalar) const {
Mat4 result;
for (int i = 0; i < 16; ++i) {
result.data[i] = data[i] * scalar;
}
return result;
}
Mat4 operator/(T scalar) const {
Mat4 result;
for (int i = 0; i < 16; ++i) {
result.data[i] = data[i] / scalar;
}
return result;
}
Vec4<T> operator*(const Vec4<T>& vec) const {
return Vec4<T>(
m00 * vec.x + m01 * vec.y + m02 * vec.z + m03 * vec.w,
m10 * vec.x + m11 * vec.y + m12 * vec.z + m13 * vec.w,
m20 * vec.x + m21 * vec.y + m22 * vec.z + m23 * vec.w,
m30 * vec.x + m31 * vec.y + m32 * vec.z + m33 * vec.w
);
}
Vec3<T> transformPoint(const Vec3<T>& point) const {
Vec4<T> result = *this * Vec4<T>(point, static_cast<T>(1));
return result.xyz() / result.w;
}
Vec3<T> transformDirection(const Vec3<T>& direction) const {
Vec4<T> result = *this * Vec4<T>(direction, static_cast<T>(0));
return result.xyz();
}
Mat4& operator+=(const Mat4& other) {
*this = *this + other;
return *this;
}
Mat4& operator-=(const Mat4& other) {
*this = *this - other;
return *this;
}
Mat4& operator*=(const Mat4& other) {
*this = *this * other;
return *this;
}
Mat4& operator*=(T scalar) {
*this = *this * scalar;
return *this;
}
Mat4& operator/=(T scalar) {
*this = *this / scalar;
return *this;
}
bool operator==(const Mat4& other) const {
for (int i = 0; i < 16; ++i) {
if (data[i] != other.data[i]) return false;
}
return true;
}
bool operator!=(const Mat4& other) const {
return !(*this == other);
}
// Matrix operations
T determinant() const {
// Using Laplace expansion for 4x4 determinant
T det = 0;
det += m00 * (m11 * (m22 * m33 - m23 * m32) - m12 * (m21 * m33 - m23 * m31) + m13 * (m21 * m32 - m22 * m31));
det -= m01 * (m10 * (m22 * m33 - m23 * m32) - m12 * (m20 * m33 - m23 * m30) + m13 * (m20 * m32 - m22 * m30));
det += m02 * (m10 * (m21 * m33 - m23 * m31) - m11 * (m20 * m33 - m23 * m30) + m13 * (m20 * m31 - m21 * m30));
det -= m03 * (m10 * (m21 * m32 - m22 * m31) - m11 * (m20 * m32 - m22 * m30) + m12 * (m20 * m31 - m21 * m30));
return det;
}
Mat4 transposed() const {
return Mat4(m00, m10, m20, m30,
m01, m11, m21, m31,
m02, m12, m22, m32,
m03, m13, m23, m33);
}
Mat4 inverse() const {
T det = determinant();
if (std::abs(det) < static_cast<T>(1e-10)) {
return Mat4(); // Return identity if not invertible
}
Mat4 result;
T invDet = static_cast<T>(1) / det;
// Calculate inverse using adjugate matrix
result.m00 = (m11 * (m22 * m33 - m23 * m32) - m12 * (m21 * m33 - m23 * m31) + m13 * (m21 * m32 - m22 * m31)) * invDet;
result.m01 = (m01 * (m22 * m33 - m23 * m32) - m02 * (m21 * m33 - m23 * m31) + m03 * (m21 * m32 - m22 * m31)) * -invDet;
result.m02 = (m01 * (m12 * m33 - m13 * m32) - m02 * (m11 * m33 - m13 * m31) + m03 * (m11 * m32 - m12 * m31)) * invDet;
result.m03 = (m01 * (m12 * m23 - m13 * m22) - m02 * (m11 * m23 - m13 * m21) + m03 * (m11 * m22 - m12 * m21)) * -invDet;
result.m10 = (m10 * (m22 * m33 - m23 * m32) - m12 * (m20 * m33 - m23 * m30) + m13 * (m20 * m32 - m22 * m30)) * -invDet;
result.m11 = (m00 * (m22 * m33 - m23 * m32) - m02 * (m20 * m33 - m23 * m30) + m03 * (m20 * m32 - m22 * m30)) * invDet;
result.m12 = (m00 * (m12 * m33 - m13 * m32) - m02 * (m10 * m33 - m13 * m30) + m03 * (m10 * m32 - m12 * m30)) * -invDet;
result.m13 = (m00 * (m12 * m23 - m13 * m22) - m02 * (m10 * m23 - m13 * m20) + m03 * (m10 * m22 - m12 * m20)) * invDet;
result.m20 = (m10 * (m21 * m33 - m23 * m31) - m11 * (m20 * m33 - m23 * m30) + m13 * (m20 * m31 - m21 * m30)) * invDet;
result.m21 = (m00 * (m21 * m33 - m23 * m31) - m01 * (m20 * m33 - m23 * m30) + m03 * (m20 * m31 - m21 * m30)) * -invDet;
result.m22 = (m00 * (m11 * m33 - m13 * m31) - m01 * (m10 * m33 - m13 * m30) + m03 * (m10 * m31 - m11 * m30)) * invDet;
result.m23 = (m00 * (m11 * m23 - m13 * m21) - m01 * (m10 * m23 - m13 * m20) + m03 * (m10 * m21 - m11 * m20)) * -invDet;
result.m30 = (m10 * (m21 * m32 - m22 * m31) - m11 * (m20 * m32 - m22 * m30) + m12 * (m20 * m31 - m21 * m30)) * -invDet;
result.m31 = (m00 * (m21 * m32 - m22 * m31) - m01 * (m20 * m32 - m22 * m30) + m02 * (m20 * m31 - m21 * m30)) * invDet;
result.m32 = (m00 * (m11 * m32 - m12 * m31) - m01 * (m10 * m32 - m12 * m30) + m02 * (m10 * m31 - m11 * m30)) * -invDet;
result.m33 = (m00 * (m11 * m22 - m12 * m21) - m01 * (m10 * m22 - m12 * m20) + m02 * (m10 * m21 - m11 * m20)) * invDet;
return result;
}
// Access operators
T& operator()(int row, int col) {
return m[row][col];
}
const T& operator()(int row, int col) const {
return m[row][col];
}
T& operator[](int index) {
return data[index];
}
const T& operator[](int index) const {
return data[index];
}
std::string toString() const {
return "Mat4([" + std::to_string(m00) + ", " + std::to_string(m01) + ", " + std::to_string(m02) + ", " + std::to_string(m03) + "],\n" +
" [" + std::to_string(m10) + ", " + std::to_string(m11) + ", " + std::to_string(m12) + ", " + std::to_string(m13) + "],\n" +
" [" + std::to_string(m20) + ", " + std::to_string(m21) + ", " + std::to_string(m22) + ", " + std::to_string(m23) + "],\n" +
" [" + std::to_string(m30) + ", " + std::to_string(m31) + ", " + std::to_string(m32) + ", " + std::to_string(m33) + "])";
}
};
// Stream output operator
template<typename T>
inline std::ostream& operator<<(std::ostream& os, const Mat4<T>& mat) {
os << mat.toString();
return os;
}
// Scalar multiplication from left
template<typename T>
inline Mat4<T> operator*(T scalar, const Mat4<T>& mat) {
return mat * scalar;
}
using Mat4f = Mat4<float>;
using Mat4d = Mat4<double>;
#endif