From 4b956ab8dd08229c1b5d66f877139014bda79743 Mon Sep 17 00:00:00 2001
From: cinnaboot <cinnaboot@protonmail.com>
Date: Wed, 25 May 2022 12:30:41 -0400
Subject: [PATCH] move Ellipse3D to game.h

---
 src/game.cpp   | 39 ++++++++++++++++++++++++++++++++-------
 src/game.h     | 23 ++++++++++++++++++++++-
 src/orbits.cpp | 28 ----------------------------
 src/orbits.h   | 16 ----------------
 4 files changed, 54 insertions(+), 52 deletions(-)

diff --git a/src/game.cpp b/src/game.cpp
index a336995..0406286 100644
--- a/src/game.cpp
+++ b/src/game.cpp
@@ -24,12 +24,37 @@ getFreeOrbit(GameState* gs)
 }
 
 void
-disableGameOrbit(GameOrbit* orbit)
+disableGameOrbit(GameState* gs, GameOrbit* orbit)
 {
-	orbit->in_use = false;
-	orbit->selected = false;
-	orbit->system = {0};
-	orbit->grav_body = nullptr;
-	orbit->ellipse_entity = nullptr;
-	orbit->satellite_entity = nullptr;
+	if (gs->last_selected_orbit == orbit)
+		gs->last_selected_orbit = nullptr;
+
+	*orbit = {0};
+}
+
+Ellipse3D
+ellipse3DInit(EllipseParameters ep, uint vert_count)
+{
+	assert(ep.a > 0 && ep.b > 0 &&
+		ep.a >= ep.b &&
+		vert_count > 0);
+
+	Ellipse3D e3d = { nullptr, vert_count};
+	// FIXME: should be allocated from GameState->arena
+	e3d.vertices = UTIL_ALLOC(vert_count, vec3);
+	ellipse3DUpdate(ep, e3d);
+	return e3d;
+}
+
+void
+ellipse3DUpdate(EllipseParameters ep, Ellipse3D& e3d)
+{
+	double angle = 2 * M_PI / e3d.vert_count;
+
+	for (uint i = 0; i < e3d.vert_count; i++) {
+		double a = angle * i;
+		// NOTE: solving for distance in polar coordinates relative to focus
+		double r = ep.a * (1 - pow(ep.e, 2)) / (1 + ep.e * cos(a));
+		e3d.vertices[i] = vec3(polarToRect(a, r), 0);
+	}
 }
diff --git a/src/game.h b/src/game.h
index 7f972ed..d473aed 100644
--- a/src/game.h
+++ b/src/game.h
@@ -1,12 +1,25 @@
 #pragma once
 
+#include <glm/glm.hpp>
+using glm::vec3;
+
 #include "tangerine.h"
 #include "orbits.h"
 
 
+#define DEFAULT_ORBIT_VERTICES 256
+
+
+struct Ellipse3D
+{
+	vec3* vertices;
+	uint vert_count;
+};
+
 struct GameOrbit
 {
 	TwoBodySystem system;
+	Ellipse3D e3d;
 
 	Entity* grav_body;
 	Entity* ellipse_entity;
@@ -31,4 +44,12 @@ struct GameState
 
 GameOrbit* getFreeOrbit(GameState* gs);
 
-void disableGameOrbit(GameOrbit* orbit);
+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);
diff --git a/src/orbits.cpp b/src/orbits.cpp
index d68f0f4..d393e52 100644
--- a/src/orbits.cpp
+++ b/src/orbits.cpp
@@ -11,7 +11,6 @@ systemInit(TwoBodySystem& system, GravBody gb, OrbitalElements el)
 	system.body = gb;
 	system.elements = el;
 	system.ep = ellipseInitAE(el.a, el.e);
-	system.e3d = ellipseInit3D(system.ep, ELLIPSE_VERT_COUNT);
 	system.epsilon = orbitGetSpecificEnergy(system.ep.a, gb.mu);
 	system.h = orbitGetAngularMomentum(system.ep.p, gb.mu);
 	system.orbital_period = orbitGetPeriod(system.ep.a, gb.mu);
@@ -49,20 +48,6 @@ ellipseInitAE(double a, double e)
 	return ellipseInitAB(a, b);
 }
 
-Ellipse3D
-ellipseInit3D(EllipseParameters ep, uint vert_count)
-{
-	assert(ep.a > 0 && ep.b > 0 &&
-		ep.a >= ep.b &&
-		vert_count > 0);
-
-	Ellipse3D e3d = { nullptr, vert_count};
-	// TODO: need to free this allocation at some point
-	e3d.vertices = UTIL_ALLOC(vert_count, glm::vec3);
-	ellipse3DUpdate(ep, e3d);
-	return e3d;
-}
-
 OrbitalElements
 orbitInit(double a, double e)
 {
@@ -74,19 +59,6 @@ orbitInit(double a, double e)
 	return o;
 }
 
-void
-ellipse3DUpdate(EllipseParameters ep, Ellipse3D& e3d)
-{
-	double angle = 2 * M_PI / e3d.vert_count;
-
-	for (uint i = 0; i < e3d.vert_count; i++) {
-		double a = angle * i;
-		// NOTE: solving for distance in polar coordinates relative to focus
-		double r = ep.a * (1 - pow(ep.e, 2)) / (1 + ep.e * cos(a));
-		e3d.vertices[i] = glm::vec3(polarToRect(a, r), 0);
-	}
-}
-
 
 //
 // NOTE: propagate anomaly functions:
diff --git a/src/orbits.h b/src/orbits.h
index a3e9805..4b9c9e4 100644
--- a/src/orbits.h
+++ b/src/orbits.h
@@ -30,13 +30,6 @@ struct OrbitalElements
 	double nu;		// (ν) true anomaly at T0
 };
 
-// FIXME: move to game.h
-struct Ellipse3D
-{
-	glm::vec3* vertices;
-	uint vert_count;
-};
-
 struct GravBody
 {
 	double mu;			// (μ) gravitational parameter
@@ -60,7 +53,6 @@ struct TwoBodySystem
 	GravBody body;
 	Satellite sat;
 	EllipseParameters ep;
-	Ellipse3D e3d; // FIXME: should be direct child of GameOrbit
 	OrbitalElements elements;
 
 	double epsilon;			// (ε) specific orbital energy, MJ/kg
@@ -109,14 +101,6 @@ ellipsesEqual(EllipseParameters& e1, EllipseParameters& e2)
 		e1.e == e2.e);
 }
 
-// NOTE: create vertices for a 3d ellipse
-// 	all vertices are in the x/y plane with z = 0
-Ellipse3D
-ellipseInit3D(EllipseParameters ep, uint vert_count);
-
-void
-ellipse3DUpdate(EllipseParameters ep, Ellipse3D& e3d);
-
 OrbitalElements
 orbitInit(double a, double e);