update ellipse colors when selecting from gooey

src/game.cpp

@@ -58,3 +58,42 @@ ellipse3DUpdate(EllipseParameters ep, Ellipse3D& e3d)
 		e3d.vertices[i] = vec3(polarToRect(a, r), 0);
 	}
 }
+
+void
+changeOrbitColor(GameOrbit* orbit, vec3* color_data)
+{
+	GLBuffer* color_buf;
+	GLMesh* gl_mesh = &orbit->ellipse_entity->meshes[0];
+
+	for (u32 i = 0; i < gl_mesh->num_vertex_attrib_buffers; i ++) {
+		if (utilCStrMatch(gl_mesh->vertex_attrib_buffers[i].name, "color"))
+			color_buf = &gl_mesh->vertex_attrib_buffers[i];
+	}
+
+	assert(color_buf && color_buf->data_size == orbit->e3d.vert_count * 3 * 4);
+	updateGLBuffer(color_buf, color_data);
+}
+
+void
+updateOrbitColors(GameOrbit* last_selected_orbit, GameOrbit* orbit)
+{
+	assert(orbit && orbit->ellipse_entity);
+
+	// FIXME: need to allocate these somewhere other than stack
+	static vec3 selected_colors[DEFAULT_ORBIT_VERTICES];
+	static vec3 default_colors[DEFAULT_ORBIT_VERTICES];
+
+	for (u32 i = 0; i < DEFAULT_ORBIT_VERTICES; i++)
+		selected_colors[i] = SELECTED_ELLIPSE_COLOR;
+
+	changeOrbitColor(orbit, selected_colors);
+
+	// repeat for last orbit
+	if (last_selected_orbit != nullptr) {
+		for (u32 i = 0; i < DEFAULT_ORBIT_VERTICES; i++)
+			default_colors[i] = DEFAULT_ELLIPSE_COLOR;
+
+		changeOrbitColor(last_selected_orbit, default_colors);
+	}
+}
+

src/game.h

@@ -9,6 +9,9 @@ using glm::vec3;
 
 #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
 {
@@ -40,6 +43,8 @@ struct GameState
 	GameOrbit* orbits;
 	u32 num_orbits;
 	u32 max_orbits;
+
+	GameOrbit* last_selected_orbit;
 };
 
 GameOrbit* getFreeOrbit(GameState* gs);

src/main.cpp

@@ -59,10 +59,10 @@ initLights(RenderState* rs)
 	updateGLBuffer(lights_ubo, lb->buffer);
 }
 
-// FIXME: could pass EllipseParameters and Ellipse3D instead of TwoBodySystem
 Entity*
 initEllipseEntity(RenderState* rs,
-	TwoBodySystem* system,
+	const EllipseParameters& ep,
+	Ellipse3D& e3d,
 	u32 num_vertices)
 {
 	// FIXME: it might be worth using stack memory here, and in
@@ -152,52 +152,66 @@ initSatelliteEntity(RenderState* rs, const char* name)
 	return e;
 }
 
-void
+GameOrbit*
+loadOrbit(GameState* gs,
+			RenderState* rs,
+			const GravBody& body,
+			const OrbitalElements& elements,
+			RenderGroup* rg,
+			const char* sat_name)
+{
+	GameOrbit* orbit = getFreeOrbit(gs);
+	systemInit(orbit->system, body, elements);
+
+	orbit->ellipse_entity = initEllipseEntity(rs,
+								orbit->system.ep,
+								orbit->e3d,
+								DEFAULT_ORBIT_VERTICES);
+	setEntityPosition(orbit->ellipse_entity, vec3(0, 0, 0));
+	rotateEntity(orbit->ellipse_entity, vec3(1, 0, 0), (float) M_PI / 2);
+
+	orbit->satellite_entity = initSatelliteEntity(rs, sat_name);
+	scaleEntity(orbit->satellite_entity, 1 / SCALING);
+	rotateEntity(orbit->satellite_entity, vec3(1, 0, 0), (float) M_PI / 2);
+	setEntityPosition(orbit->satellite_entity,
+			orbit->e3d.vertices[0]);
+
+	return orbit;
+}
+
+bool
 loadScene(GameState* gs, RenderState* rs)
 {
 	initCamera(rs, vec3(0, -75 / SCALING, 0), vec3(0, 0, 0), vec3(0,0,1));
 	initLights(rs);
 	gs->running = true;
 
-	double a = 26564.5;		// semi-major axis in km
-	double e = 0.7411;		// eccentricity
 	double mu = 398601.68;	// gravitational parameter
 	double r = 6378;		// body radius in km
-
-	GameOrbit* orbit_1 = getFreeOrbit(gs);
-	systemInit(orbit_1->system, gravBodyInit(mu, r), orbitInit(a, e));
+	GravBody body = gravBodyInit(mu, r);
+	initPlanetEntity(rs, r);
 
 	// TODO: streamline the boilerplate in init_X_Entity functions
 	ShaderProgram* shader = getShaderByName("colored_vertices", rs->gl_ctx);
-	initRenderGroup(
-		getFreeRenderGroup(rs), rs->rg_arena, shader, 256, "manual mesh group");
+	RenderGroup* rg = getFreeRenderGroup(rs);
+	initRenderGroup(rg, rs->rg_arena, shader, 256, "manual mesh group");
 
-	orbit_1->ellipse_entity = initEllipseEntity(rs, &orbit_1->system, 256);
-	setEntityPosition(orbit_1->ellipse_entity, vec3(0, 0, 0));
-	rotateEntity(orbit_1->ellipse_entity, vec3(1, 0, 0), (float) M_PI / 2);
+	double a = 26564.5;		// semi-major axis in km
+	double e = 0.7411;		// eccentricity
+	GameOrbit* orbit_1 = loadOrbit(gs, rs, body, orbitInit(a, e), rg, "sat_01");
+	// NOTE: set as selected orbit
+	updateOrbitColors(nullptr, orbit_1);
+	gs->last_selected_orbit = orbit_1;
 
-	initPlanetEntity(rs, r);
+	double a_2 = r + 10000;
+	double e_2 = 0;
+	loadOrbit(gs, rs, body, orbitInit(a_2, e_2), rg, "sat_02");
 
-	orbit_1->satellite_entity = initSatelliteEntity(rs, "ship 01");
-	scaleEntity(orbit_1->satellite_entity, 1 / SCALING);
-	rotateEntity(orbit_1->satellite_entity, vec3(1, 0, 0), (float) M_PI / 2);
-	setEntityPosition(orbit_1->satellite_entity,
-			orbit_1->system.e3d.vertices[0]);
+	double a_3 = r + 40000;
+	double e_3 = 0.5;
+	loadOrbit(gs, rs, body, orbitInit(a_3, e_3), rg, "sat_03");
 
-	// NOTE: testing multiple orbits
-	double a_2 = r + 10000; // km
-	double e_2 = 0;
-	GameOrbit* orbit_2 = getFreeOrbit(gs);
-	systemInit(orbit_2->system, gravBodyInit(mu, r), orbitInit(a_2, e_2));
-	orbit_2->ellipse_entity = initEllipseEntity(rs, &orbit_2->system, 256);
-	setEntityPosition(orbit_2->ellipse_entity, vec3(0, 0, 0));
-	rotateEntity(orbit_2->ellipse_entity, vec3(1, 0, 0), (float) M_PI / 2);
-
-	orbit_2->satellite_entity = initSatelliteEntity(rs, "ship 02");
-	scaleEntity(orbit_2->satellite_entity, 1 / SCALING);
-	rotateEntity(orbit_2->satellite_entity, vec3(1, 0, 0), (float) M_PI / 2);
-	setEntityPosition(orbit_2->satellite_entity,
-			orbit_2->system.e3d.vertices[0]);
+	return true;
 }
 
 void
@@ -258,23 +272,31 @@ preFrameCallback(RenderState* rs, void* user_data = nullptr)
 	u64 last_sdl_tick = gs->game_time_ms;
 	gs->game_time_ms = SDL_GetTicks64();
 	u64 current_tick = gs->game_time_ms - last_sdl_tick;
+	double time_step = 0;
 
 	// NOTE: update sim time base on time since last frame * sim_speed
 	if (gs->running) {
 		u64 last_game_tick = gs->sim_time_ms;
 		gs->sim_time_ms = gs->sim_time_ms + current_tick * gs->sim_speed;
 		u32 diff_ms = gs->sim_time_ms - last_game_tick;
-		double time_step = double(diff_ms) / 1000;
+		time_step = double(diff_ms) / 1000;
+	}
 
 	for (u32 i = 0; i < gs->num_orbits; i++) {
 		GameOrbit& orbit = gs->orbits[i];
 
 		if (orbit.in_use && orbit.satellite_entity) {
+			if (gs->running) {
 				updateSatelliteModel(orbit.system, time_step);
 				updateSatelliteEntity(orbit.satellite_entity, orbit.system.sat);
 				// TODO: update EllipseEntity per frame
 				//updateOrbit(gs->system, ellipse_entity);
 			}
+
+			if (orbit.selected && &orbit != gs->last_selected_orbit) {
+				updateOrbitColors(gs->last_selected_orbit, &orbit);
+				gs->last_selected_orbit = &orbit;
+			}
 		}
 	}
 }
@@ -312,7 +334,11 @@ main()
 	gs.max_orbits = DEFAULT_MAX_ORBITS;
 	gs.orbits = ARENA_ALLOC(gs.arena, GameOrbit, DEFAULT_MAX_ORBITS);
 
-	loadScene(&gs, rs);
+	if (!loadScene(&gs, rs)) {
+		LOGF(Error, "Error loading scene\n");
+		return 1;
+	}
+
 	doRenderLoop(rs, 60, preFrameCallback, postFrameCallback, &gs);
 	gooFree();
 	freeRenderState(rs);