Brought in some of amit's code to study and try out. amt/ has it.

amt/raycaster.hpp

@@ -0,0 +1,95 @@
+#pragma once
+
+#include <fmt/core.h>
+#include <SFML/Graphics.hpp>
+#include <SFML/Graphics/Image.hpp>
+#include <numbers>
+#include <algorithm>
+#include <cmath>
+#include "amt/matrix.hpp"
+#include <cstdlib>
+#include <array>
+#include "dbc.hpp"
+#include <memory>
+
+using Matrix = amt::Matrix<int>;
+
+struct Sprite {
+  double x;
+  double y;
+  int texture;
+  // ZED: this should be a separate transform parameter
+  double elevation=0;
+  int uDiv=1;
+  int vDiv=1;
+};
+
+using RGBA = uint32_t;
+
+struct TexturePack {
+  int NUM_SPRITES=1;
+  int NUM_TEXTURES=11;
+  int TEXTURE_WIDTH=256; // must be power of two
+  int TEXTURE_HEIGHT=256; // must be power of two
+
+  std::vector<std::vector<uint32_t>> images;
+  std::vector<Sprite> SPRITE{{4.0, 3.55, 8}};
+  const int floor = 3;
+  const int ceiling = 6;
+
+  void load_textures();
+  std::vector<uint32_t> load_image(const char *filename);
+  Sprite &get_sprite(size_t sprite_num);
+  std::vector<uint32_t>& get(size_t num);
+};
+
+struct Raycaster {
+  int PITCH=0;
+
+  TexturePack textures;
+  double posX = 0;
+  double posY = 0;
+
+  // initial direction vector
+  double dirX = -1;
+  double dirY = 0;
+
+  // the 2d raycaster version of camera plane
+  double planeX = 0;
+  double planeY = 0.66;
+  sf::Texture view_texture;
+  sf::Sprite view_sprite;
+
+  //ZED: USE smart pointer for this
+  std::unique_ptr<RGBA[]> pixels = nullptr;
+
+  int $width;
+  int $height;
+  sf::RenderWindow& $window;
+  Matrix& $map;
+  std::vector<int> spriteOrder;
+  std::vector<double> spriteDistance;
+  std::vector<double> ZBuffer; // width
+
+  Raycaster(sf::RenderWindow& window, Matrix &map, int width, int height);
+
+  void draw_pixel_buffer();
+  void clear();
+  void cast_rays();
+  void draw_ceiling_floor();
+  void sprite_casting();
+  void sort_sprites(std::vector<int>& order, std::vector<double>& dist, int amount);
+  void render();
+
+  bool empty_space(int new_x, int new_y);
+
+  void run(double speed, int dir);
+  void rotate(double speed, int dir);
+  void position_camera(float player_x, float player_y);
+
+  void set_position(int x, int y);
+  inline size_t pixcoord(int x, int y) {
+    return ((y) * $width) + (x);
+  }
+
+};