From 64755fc33dc6c964b73622085a589563be24a1fe Mon Sep 17 00:00:00 2001
From: = <=>
Date: Tue, 23 Mar 2021 18:15:30 -0400
Subject: [PATCH] add more inputs to demo application

---
 src/gooey.cpp  | 49 +++++++++++++++++++++++++++++++++----------------
 src/gooey.h    |  2 +-
 src/main.cpp   | 18 ++++++++++++------
 src/orbits.cpp |  1 +
 src/orbits.h   |  3 +++
 5 files changed, 50 insertions(+), 23 deletions(-)

diff --git a/src/gooey.cpp b/src/gooey.cpp
index 6f4eb49..93381af 100644
--- a/src/gooey.cpp
+++ b/src/gooey.cpp
@@ -42,42 +42,59 @@ gooProcessEvent(SDL_Event& e)
 }
 
 void
-gooDraw(SDL_Window* window, orbital_elements& orbit)
+gooDraw(SDL_Window* window, orbital_elements& orbit, uint& time_step)
 {
-	// Start the Dear ImGui frame
 	ImGui_ImplOpenGL3_NewFrame();
 	ImGui_ImplSDL2_NewFrame(window);
 	ImGui::NewFrame();
 
-	ImGui::SetNextWindowPos(ImVec2(0,0));
-	ImGui::SetNextWindowSize(ImVec2(300,270));
+	const static int w = 300;
+	int x = 0, y = 0;
+	SDL_GetWindowSize(window, &x, &y);
+	ImGui::SetNextWindowPos(ImVec2(x - w, 0));
+	ImGui::SetNextWindowSize(ImVec2(w, y));
 	ImGui::Begin("Orbital Elements");
 
 	ImGui::Text("iota, inclination:            %f", orbit.iota);
 	ImGui::Text("omega, argument of periapsis: %f", orbit.omega);
 	ImGui::Text("mu, gravitational parameter:  %f", orbit.mu);
-	ImGui::Text("nu, true anomoly:             %f", orbit.nu);
+	ImGui::Text("nu, true anomoly: ");
+	ImGui::InputDouble("##orbit.nu", &orbit.nu, 0.1f);
+	ImGui::SameLine();
+	ImGui::Text(" radians");
 	ImGui::Spacing();
 
 	ImGui::Separator();
 	ImGui::Spacing();
 	ImGui::Text("Ellipse Parameters:");
-	ImGui::Text("a: %f km", orbit.ep.a);
-	ImGui::Text("b: %f km", orbit.ep.b);
-	ImGui::Text("e: %f", orbit.ep.e);
-	ImGui::Text("c: %f km", orbit.ep.c);
-
-
-	ImGui::Text("a:");
-	ImGui::SameLine();
+	ImGui::Text("semi-major axis, a:     ");
 	ImGui::InputDouble("##orbit.ep.a", &orbit.ep.a, 1000.0f);
-
-	ImGui::Text("e:");
 	ImGui::SameLine();
+	ImGui::Text(" km");
+	ImGui::Text("semi-minor axis, b:     %f km", orbit.ep.b);
+	ImGui::Text("eccentricity, e:        ");
 	ImGui::InputDouble("##orbit.ep.e", &orbit.ep.e, 0.01f);
+	ImGui::Text("linear eccentricity, c: %f km", orbit.ep.c);
+	ImGui::Spacing();
 
-	ImGui::End();
+	ImGui::Separator();
+	ImGui::Spacing();
+	ImGui::Text("Other Parameters");
+	ImGui::Spacing();
+	ImGui::Text("time_step:");
+	ImGui::SameLine();
+	uint step = 1;
+	ImGui::InputScalar("##other.time_step", ImGuiDataType_U32, &time_step, &step);
+	ImGui::Spacing();
+	ImGui::Text("Satellite Parameters:");
+	ImGui::Text("position:");
+	ImGui::Text("	x: %f km", orbit.pos.x);
+	ImGui::Text("	y: %f km", orbit.pos.y);
+	ImGui::Text("	z: %f km", orbit.pos.z);
+	ImGui::Text("radial velocity:");
+	ImGui::Text("flight path angle:");
 
+	ImGui::End();
 	ImGui::Render();
 	ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
 }
diff --git a/src/gooey.h b/src/gooey.h
index 15cdbb5..781cb9a 100644
--- a/src/gooey.h
+++ b/src/gooey.h
@@ -16,5 +16,5 @@ bool
 gooProcessEvent(SDL_Event &e);
 
 void
-gooDraw(SDL_Window* window, orbital_elements& orbit);
+gooDraw(SDL_Window* window, orbital_elements& orbit, uint& time_step);
 
diff --git a/src/main.cpp b/src/main.cpp
index e0cfde3..310d62f 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -18,6 +18,7 @@
 const double SCALING = 0.001;
 static orbital_elements g_orbit = {};
 static ellipse_3d g_ellipse3d;
+static uint g_time_step = 100;
 
 
 simple_mesh*
@@ -82,12 +83,10 @@ updateSatellitePosition(entity& satellite)
 		glm::rotate(glm::mat4(1.0), (float) M_PI_2, glm::vec3(1, 0, 0));
 
 	// TODO: decouple framerate from time_step
-	unsigned int time_step = 100; // NOTE: seconds
-
-	g_orbit.nu = getPropagatedTrueAnomaly(g_orbit, g_orbit.nu, time_step);
+	g_orbit.nu = getPropagatedTrueAnomaly(g_orbit, g_orbit.nu, g_time_step);
 	double r2 = getRadialPosition(g_orbit.ep, g_orbit.nu);
 	glm::vec2 coords = polarToRect(g_orbit.nu, r2);
-	glm::vec3 v = glm::vec3(coords, 0);
+	glm::vec3 v = g_orbit.pos = glm::vec3(coords, 0);
 	entSetWorldPosition(satellite, xform * glm::vec4(v.x, v.y, v.z, 1));
 }
 
@@ -129,7 +128,7 @@ postFrameCallback(render_state* rs)
 {
 	static orbital_elements c_orb = {};
 	orbitCopy(g_orbit, c_orb);
-	gooDraw(rs->handles->window, c_orb);
+	gooDraw(rs->handles->window, c_orb, g_time_step);
 
 	// TODO: will need more validation from GUI as added
 	if (!ellipsesEqual(c_orb.ep, g_orbit.ep)) {
@@ -148,13 +147,20 @@ postFrameCallback(render_state* rs)
 			updateOrbit(g_orbit, g_ellipse3d, ellipse_entity);
 		}
 	}
+
+	if (c_orb.nu != g_orbit.nu &&
+		((c_orb.nu >= 0 && c_orb.nu <= M_PI) ||
+		(c_orb.nu < 0 && c_orb.nu >= -1 * M_PI)))
+	{
+		g_orbit.nu = c_orb.nu;
+	}
 }
 
 int
 main()
 {
 	render_state* rs = renInit("orbital shipping",
-		glm::vec2(1280, 720),
+		glm::vec2(1280, 800),
 		SDL_INIT_TIMER);
 
 	if (rs == nullptr) {
diff --git a/src/orbits.cpp b/src/orbits.cpp
index 53274e8..a6e8e15 100644
--- a/src/orbits.cpp
+++ b/src/orbits.cpp
@@ -61,6 +61,7 @@ orbitCopy(const orbital_elements& o1, orbital_elements& o2)
 	o2.omega = o1.omega;
 	o2.mu = o1.mu;
 	o2.nu = o1.nu;
+	o2.pos = o1.pos;
 }
 
 ellipse_3d
diff --git a/src/orbits.h b/src/orbits.h
index 9a363bc..112e2d5 100644
--- a/src/orbits.h
+++ b/src/orbits.h
@@ -26,6 +26,9 @@ struct orbital_elements
 	double omega;	// NOTE: (ω) argument of periapsis
 	double mu;		// NOTE: (μ) gravitational parameter
 	double nu;		// NOTE: (ν) true anomaly
+
+	glm::vec3 pos;	// NOTE: true anomaly in 3d with ep.f2 at origin
+	double radial_velocity;
 };
 
 struct ellipse_3d