orbital_shipping/src/game.h

#pragma once

#include <glm/glm.hpp>
using glm::vec3;

#include "tangerine.h"
#include "orbits.h"


#define DEFAULT_ORBIT_VERTICES 256

const vec3 DEFAULT_ELLIPSE_COLOR = vec3(0.5, 0.5, 0.5);
const vec3 SELECTED_ELLIPSE_COLOR = vec3(0.7, 0.2, 0.2);


struct Ellipse3D
{
	vec3* vertices;
	uint vert_count;
};

struct GameOrbit
{
	TwoBodySystem system;
	Ellipse3D e3d;

	Entity* grav_body;
	Entity* ellipse_entity;
	Entity* satellite_entity;
	bool in_use;
	bool selected;
};

struct GameState
{
	bool running;
	MemoryArena* arena;

	u64 game_time_ms;
	u64 sim_time_ms;
	float sim_speed;

	GameOrbit* orbits;
	u32 num_orbits;
	u32 max_orbits;

	GameOrbit* last_selected_orbit;
};

GameOrbit* getFreeOrbit(GameState* gs);

void disableGameOrbit(GameState* gs, GameOrbit* orbit);

// NOTE: create vertices for a 3d ellipse
// 	all vertices are in the x/y plane with z = 0
Ellipse3D ellipse3DInit(EllipseParameters ep, uint vert_count);

void ellipse3DUpdate(EllipseParameters ep, Ellipse3D& e3d);

void updateOrbitColors(GameOrbit* last_selected_orbit, GameOrbit* orbit);