feat: add trail

include/sims.hpp

@@ -1,14 +1,26 @@
 #ifndef SIMS_HPP
-    #define SIMS_HPP
-    #include <SDL3/SDL_render.h>
+#define SIMS_HPP
 
-namespace sims {
-    typedef struct {
-        int x;
-        int y;
-        int r;
-    } body;
-    void two_bodies(SDL_Renderer *r);
-}
+#include <SDL3/SDL_render.h>
+#include <utility>
+
+class Body {
+private:
+    float x;
+    float y;
+    float vx = 1;
+    float vy = 1;
+    std::pair<float, float> old_positions[100];
+
+public:
+    SDL_Renderer* renderer;
+
+    Body(int x_pos, int y_pos);
+
+    void draw_tail();
+    void live();
+};
+
+void two_bodies(SDL_Renderer* r, Body &a, Body &b);
 
 #endif