ladybird/Userland/Libraries/LibGfx/Matrix4x4.h
2022-04-01 21:24:45 +01:00

86 lines
2.5 KiB
C++

/*
* Copyright (c) 2020, Stephan Unverwerth <s.unverwerth@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Math.h>
#include <LibGfx/Matrix.h>
#include <LibGfx/Vector3.h>
#include <LibGfx/Vector4.h>
namespace Gfx {
template<typename T>
using Matrix4x4 = Matrix<4, T>;
template<typename T>
constexpr static Vector4<T> operator*(Matrix4x4<T> const& m, Vector4<T> const& v)
{
auto const& elements = m.elements();
return Vector4<T>(
v.x() * elements[0][0] + v.y() * elements[0][1] + v.z() * elements[0][2] + v.w() * elements[0][3],
v.x() * elements[1][0] + v.y() * elements[1][1] + v.z() * elements[1][2] + v.w() * elements[1][3],
v.x() * elements[2][0] + v.y() * elements[2][1] + v.z() * elements[2][2] + v.w() * elements[2][3],
v.x() * elements[3][0] + v.y() * elements[3][1] + v.z() * elements[3][2] + v.w() * elements[3][3]);
}
// FIXME: this is a specific Matrix4x4 * Vector3 interaction that implies W=1; maybe move this out of LibGfx
// or replace a Matrix4x4 * Vector4 operation?
template<typename T>
constexpr static Vector3<T> transform_point(Matrix4x4<T> const& m, Vector3<T> const& p)
{
auto const& elements = m.elements();
return Vector3<T>(
p.x() * elements[0][0] + p.y() * elements[0][1] + p.z() * elements[0][2] + elements[0][3],
p.x() * elements[1][0] + p.y() * elements[1][1] + p.z() * elements[1][2] + elements[1][3],
p.x() * elements[2][0] + p.y() * elements[2][1] + p.z() * elements[2][2] + elements[2][3]);
}
template<typename T>
constexpr static Matrix4x4<T> translation_matrix(Vector3<T> const& p)
{
return Matrix4x4<T>(
1, 0, 0, p.x(),
0, 1, 0, p.y(),
0, 0, 1, p.z(),
0, 0, 0, 1);
}
template<typename T>
constexpr static Matrix4x4<T> scale_matrix(Vector3<T> const& s)
{
return Matrix4x4<T>(
s.x(), 0, 0, 0,
0, s.y(), 0, 0,
0, 0, s.z(), 0,
0, 0, 0, 1);
}
template<typename T>
constexpr static Matrix4x4<T> rotation_matrix(Vector3<T> const& axis, T angle)
{
T c, s;
AK::sincos(angle, s, c);
T t = 1 - c;
T x = axis.x();
T y = axis.y();
T z = axis.z();
return Matrix4x4<T>(
t * x * x + c, t * x * y - z * s, t * x * z + y * s, 0,
t * x * y + z * s, t * y * y + c, t * y * z - x * s, 0,
t * x * z - y * s, t * y * z + x * s, t * z * z + c, 0,
0, 0, 0, 1);
}
typedef Matrix4x4<float> FloatMatrix4x4;
typedef Matrix4x4<double> DoubleMatrix4x4;
}
using Gfx::DoubleMatrix4x4;
using Gfx::FloatMatrix4x4;
using Gfx::Matrix4x4;