From 51986509269588257f95e545cf3f76adba170b63 Mon Sep 17 00:00:00 2001
From: yggdrasil75 <cblackburn7557@gmail.com>
Date: Mon, 9 Feb 2026 05:43:53 -0500
Subject: [PATCH] asdf

---
 util/grid/mesh.hpp | 119 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 119 insertions(+)
 create mode 100644 util/grid/mesh.hpp

diff --git a/util/grid/mesh.hpp b/util/grid/mesh.hpp
new file mode 100644
index 0000000..84de0a8
--- /dev/null
+++ b/util/grid/mesh.hpp
@@ -0,0 +1,119 @@
+#ifndef MESH_HPP
+#define MESH_HPP
+
+#include <vector>
+#include <array>
+#include <map>
+#include <set>
+#include <memory>
+#include <algorithm>
+#include <cmath>
+#include <iostream>
+#include "../../eigen/Eigen/Dense"
+#include "../../eigen/Eigen/Geometry"
+#include "./camera.hpp"
+
+using Vector2f = Eigen::Vector2f;
+using Vector3f = Eigen::Vector3f;
+using Vector4f = Eigen::Vector4f;
+using Matrix4f = Eigen::Matrix4f;
+using Color = Eigen::Vector3f;
+
+class Mesh {
+private:
+    int id;
+    std::vector<Vector3f> _vertices;
+    std::vector<std::vector<int>> _polys;
+    std::vector<Color> _colors;
+    mutable std::vector<Eigen::Vector3i> _tris;
+    mutable bool _needs_triangulation = true;
+public:
+    Mesh(int id, const std::vector<Vector3f>& verts, const std::vector<std::vector<int>>& polys, const std::vector<Color>& colors)
+        : id(id), _vertices(verts), _polys(polys), _colors(colors) {}
+
+    std::vector<Vector3f> vertices() {
+        return _vertices;
+    }
+
+    bool vertices(std::vector<Vector3f> verts) {
+        if (verts.size() != _colors.size()) {
+            if (_colors.size() == 1) {
+                _vertices = verts;
+                return true;
+            }
+            return false;
+        } else {
+            _vertices = verts;
+            return true;
+        }
+    }
+
+    std::vector<std::vector<int>> polys() {
+        return _polys;
+    }
+
+    void triangulate() {
+        std::vector<Eigen::Vector3i> newPols;
+        if (!_needs_triangulation) return;
+        for (auto& pol : _polys) {
+            if (pol.size() > 3) {
+                auto v0 = pol[0];
+                for (int i = 0; i < pol.size() - 1; i++) {
+                    newPols.emplace_back(Eigen::Vector3i{v0, pol[i], pol[i+1]});
+                }
+            } else if (pol.size() == 3) {
+                Eigen::Vector3i tri{pol[0], pol[1], pol[2]};
+                newPols.emplace_back(tri);
+            }
+        }
+        _tris = newPols;
+        _needs_triangulation = false; 
+    }
+
+    std::vector<Color> colors() {
+        return _colors;
+    }
+
+    bool colors(std::vector<Color> colorlist) {
+        if (colorlist.size() == 1) {
+            _colors = colorlist;
+        } else if (colorlist.size() == _vertices.size()) {
+            _colors = colorlist;
+        }
+    }
+
+    void project_2d(Camera cam, int height, int width, float near, float far) {
+        Vector3f zaxis = cam.direction - cam.origin;
+        zaxis = zaxis / zaxis.norm();
+        Vector3f xAxis = cam.up.cross(zaxis);
+        xAxis = xAxis / xAxis.norm();
+        Vector3f yAxis = zaxis.cross(xAxis);
+
+        Matrix4f viewMatrix = Matrix4f::Identity();
+        viewMatrix.block<3,1>(0,0) = xAxis;
+        viewMatrix.block<3,1>(0,1) = yAxis;
+        viewMatrix.block<3,1>(0,2) = -zaxis;
+        viewMatrix.block<3,1>(0,3) = cam.origin;
+
+        viewMatrix = viewMatrix.inverse();
+
+        float aspect = float(height) / float(width);
+        float fovrad = cam.fovRad();
+        float tanh = std::tan(fovrad / 2);
+        
+        Matrix4f projMatrix = Matrix4f::Zero();
+        projMatrix(0,0) = 1.0 / (aspect * tanh);
+        projMatrix(1,1) = 1.0 / tanh;
+        projMatrix(2,2) = -(far + near) / (near - far);
+        projMatrix(2,3) = (-2.0f * far * near) / (near - far);
+        projMatrix(3,2) = -1.0f;
+
+        Vector3f viewDir = (cam.direction - cam.origin).normalized();
+
+        Vector3f mesh_center = _vertices.colwise().mean(); 
+
+    }
+
+};
+
+#endif
\ No newline at end of file