Math: add Mat3x3 (#14)

include/hyprutils/math/Mat3x3.hpp

@@ -0,0 +1,59 @@
+#pragma once
+
+#include <array>
+#include <vector>
+#include <string>
+#include <ostream>
+
+#include "./Misc.hpp"
+
+namespace Hyprutils {
+    namespace Math {
+        class CBox;
+        class Vector2D;
+
+        class Mat3x3 {
+          public:
+            Mat3x3();
+            Mat3x3(std::array<float, 9>);
+            Mat3x3(std::vector<float>);
+
+            /* create an identity 3x3 matrix */
+            static Mat3x3 identity();
+
+            /* create an output projection matrix */
+            static Mat3x3 outputProjection(const Vector2D& size, eTransform transform);
+
+            /* get the matrix as an array, in a RTL TTB order. */
+            std::array<float, 9> getMatrix() const;
+
+            /* create a box projection matrix */
+            Mat3x3 projectBox(const CBox& box, eTransform transform, float rot = 0.F /* rad, CCW */) const;
+
+            /* in-place functions */
+            Mat3x3& transform(eTransform transform);
+            Mat3x3& rotate(float rot /* rad, CCW */);
+            Mat3x3& scale(const Vector2D& scale);
+            Mat3x3& scale(const float scale);
+            Mat3x3& translate(const Vector2D& offset);
+            Mat3x3& transpose();
+            Mat3x3& multiply(const Mat3x3& other);
+
+            /* misc utils */
+            Mat3x3      copy() const;
+            std::string toString() const;
+
+            bool        operator==(const Mat3x3& other) const {
+                return other.matrix == matrix;
+            }
+
+            friend std::ostream& operator<<(std::ostream& os, const Mat3x3& mat) {
+                os << mat.toString();
+                return os;
+            }
+
+          private:
+            std::array<float, 9> matrix;
+        };
+    }
+}

src/math/Mat3x3.cpp

@@ -0,0 +1,145 @@
+#include <hyprutils/math/Mat3x3.hpp>
+#include <hyprutils/math/Vector2D.hpp>
+#include <hyprutils/math/Box.hpp>
+#include <cmath>
+#include <unordered_map>
+#include <format>
+
+using namespace Hyprutils::Math;
+
+static std::unordered_map<eTransform, Mat3x3> transforms = {
+    {HYPRUTILS_TRANSFORM_NORMAL, std::array<float, 9>{1.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f}},
+    {HYPRUTILS_TRANSFORM_90, std::array<float, 9>{0.0f, 1.0f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f}},
+    {HYPRUTILS_TRANSFORM_180, std::array<float, 9>{-1.0f, 0.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f}},
+    {HYPRUTILS_TRANSFORM_270, std::array<float, 9>{0.0f, -1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f}},
+    {HYPRUTILS_TRANSFORM_FLIPPED, std::array<float, 9>{-1.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f}},
+    {HYPRUTILS_TRANSFORM_FLIPPED_90, std::array<float, 9>{0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f}},
+    {HYPRUTILS_TRANSFORM_FLIPPED_180, std::array<float, 9>{1.0f, 0.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f}},
+    {HYPRUTILS_TRANSFORM_FLIPPED_270, std::array<float, 9>{0.0f, -1.0f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f}},
+};
+
+Mat3x3::Mat3x3() {
+    matrix = {0};
+}
+
+Mat3x3::Mat3x3(std::array<float, 9> mat) : matrix(mat) {
+    ;
+}
+
+Mat3x3::Mat3x3(std::vector<float> mat) {
+    for (size_t i = 0; i < 9; ++i) {
+        matrix.at(i) = mat.size() < i ? mat.at(i) : 0.F;
+    }
+}
+
+Mat3x3 Mat3x3::identity() {
+    return Mat3x3(std::array<float, 9>{1.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f});
+}
+
+Mat3x3 Mat3x3::outputProjection(const Vector2D& size, eTransform transform) {
+    Mat3x3      mat;
+
+    const auto& t = transforms.at(transform);
+    float       x = 2.0f / size.x;
+    float       y = 2.0f / size.y;
+
+    // Rotation + reflection
+    mat.matrix[0] = x * t.matrix[0];
+    mat.matrix[1] = x * t.matrix[1];
+    mat.matrix[3] = y * t.matrix[3];
+    mat.matrix[4] = y * t.matrix[4];
+
+    // Translation
+    mat.matrix[2] = -copysign(1.0f, mat.matrix[0] + mat.matrix[1]);
+    mat.matrix[5] = -copysign(1.0f, mat.matrix[3] + mat.matrix[4]);
+
+    // Identity
+    mat.matrix[8] = 1.0f;
+
+    return mat;
+}
+
+std::array<float, 9> Mat3x3::getMatrix() const {
+    return matrix;
+}
+
+Mat3x3 Mat3x3::projectBox(const CBox& box, eTransform transform, float rot /* rad, CCW */) const {
+    Mat3x3     mat = Mat3x3::identity();
+
+    const auto boxSize = box.size();
+
+    mat.translate(box.pos());
+
+    if (rot != 0) {
+        mat.translate(boxSize / 2);
+        mat.rotate(rot);
+        mat.translate(-boxSize / 2);
+    }
+
+    mat.scale(boxSize);
+
+    if (transform != HYPRUTILS_TRANSFORM_NORMAL) {
+        mat.translate({0.5, 0.5});
+        mat.transform(transform);
+        mat.translate({-0.5, -0.5});
+    }
+
+    return this->copy().multiply(mat);
+}
+
+Mat3x3& Mat3x3::transform(eTransform transform) {
+    multiply(transforms.at(transform));
+    return *this;
+}
+
+Mat3x3& Mat3x3::rotate(float rot) {
+    multiply(std::array<float, 9>{(float)cos(rot), (float)-sin(rot), 0.0f, (float)sin(rot), (float)cos(rot), 0.0f, 0.0f, 0.0f, 1.0f});
+    return *this;
+}
+
+Mat3x3& Mat3x3::scale(const Vector2D& scale_) {
+    multiply(std::array<float, 9>{(float)scale_.x, 0.0f, 0.0f, 0.0f, (float)scale_.y, 0.0f, 0.0f, 0.0f, 1.0f});
+    return *this;
+}
+
+Mat3x3& Mat3x3::scale(const float scale_) {
+    return scale({scale_, scale_});
+}
+
+Mat3x3& Mat3x3::translate(const Vector2D& offset) {
+    multiply(std::array<float, 9>{1.0f, 0.0f, (float)offset.x, 0.0f, 1.0f, (float)offset.y, 0.0f, 0.0f, 1.0f});
+    return *this;
+}
+
+Mat3x3& Mat3x3::transpose() {
+    matrix = std::array<float, 9>{matrix[0], matrix[3], matrix[6], matrix[1], matrix[4], matrix[7], matrix[2], matrix[5], matrix[8]};
+    return *this;
+}
+
+Mat3x3& Mat3x3::multiply(const Mat3x3& other) {
+    std::array<float, 9> product;
+
+    product[0] = matrix[0] * other.matrix[0] + matrix[1] * other.matrix[3] + matrix[2] * other.matrix[6];
+    product[1] = matrix[0] * other.matrix[1] + matrix[1] * other.matrix[4] + matrix[2] * other.matrix[7];
+    product[2] = matrix[0] * other.matrix[2] + matrix[1] * other.matrix[5] + matrix[2] * other.matrix[8];
+
+    product[3] = matrix[3] * other.matrix[0] + matrix[4] * other.matrix[3] + matrix[5] * other.matrix[6];
+    product[4] = matrix[3] * other.matrix[1] + matrix[4] * other.matrix[4] + matrix[5] * other.matrix[7];
+    product[5] = matrix[3] * other.matrix[2] + matrix[4] * other.matrix[5] + matrix[5] * other.matrix[8];
+
+    product[6] = matrix[6] * other.matrix[0] + matrix[7] * other.matrix[3] + matrix[8] * other.matrix[6];
+    product[7] = matrix[6] * other.matrix[1] + matrix[7] * other.matrix[4] + matrix[8] * other.matrix[7];
+    product[8] = matrix[6] * other.matrix[2] + matrix[7] * other.matrix[5] + matrix[8] * other.matrix[8];
+
+    matrix = product;
+    return *this;
+}
+
+Mat3x3 Mat3x3::copy() const {
+    return *this;
+}
+
+std::string Mat3x3::toString() const {
+    return std::format("[mat3x3: {}, {}, {}, {}, {}, {}, {}, {}, {}]", matrix.at(0), matrix.at(1), matrix.at(2), matrix.at(3), matrix.at(4), matrix.at(5), matrix.at(6),
+                       matrix.at(7), matrix.at(8));
+}

tests/math.cpp

@@ -1,4 +1,5 @@
 #include <hyprutils/math/Region.hpp>
+#include <hyprutils/math/Mat3x3.hpp>
 #include "shared.hpp"
 
 using namespace Hyprutils::Math;
@@ -85,5 +86,14 @@ int main(int argc, char** argv, char** envp) {
         EXPECT(box.inside(CBox(0, 0, 100, 100)), false);
     }
 
+    // Test matrices
+    {
+        Mat3x3 jeremy = Mat3x3::outputProjection({1920, 1080}, HYPRUTILS_TRANSFORM_FLIPPED_90);
+        Mat3x3 matrixBox = jeremy.projectBox(CBox{10, 10, 200, 200}, HYPRUTILS_TRANSFORM_NORMAL).translate({100, 100}).scale({1.25F, 1.5F}).transpose();
+
+        Mat3x3 expected = std::array<float, 9>{0, 0.46296296, 0, 0.3125, 0, 0, 19.84375, 36.055557, 1};
+        EXPECT(matrixBox, expected);
+    }
+
     return ret;
 }

tests/shared.hpp

@@ -13,7 +13,7 @@ namespace Colors {
 
 #define EXPECT(expr, val)                                                                                                                                                          \
     if (const auto RESULT = expr; RESULT != (val)) {                                                                                                                               \
-        std::cout << Colors::RED << "Failed: " << Colors::RESET << #expr << ", expected " << #val << " but got " << RESULT << "\n";                                                \
+        std::cout << Colors::RED << "Failed: " << Colors::RESET << #expr << ", expected " << val << " but got " << RESULT << "\n";                                                \
         ret = 1;                                                                                                                                                                   \
     } else {                                                                                                                                                                       \
         std::cout << Colors::GREEN << "Passed " << Colors::RESET << #expr << ". Got " << val << "\n";                                                                              \