diff --git a/src/main.cpp b/src/main.cpp
index e76e85a..7000685 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -13,11 +13,15 @@
 #include "orbits.h"
 
 
-const double SCALING = 0.001;
 static bool g_running = false;
 static system_2body g_sys = {0};
 static MemoryArena* g_arena = nullptr;
 
+const double SCALING = 0.001;
+const vec4 g_light_direction = vec4(-2, 1, 3, 1);
+const vec4 g_light_color = vec4(0.5, 0.5, 0.5, 1);
+const uvec4 g_light_intensities = uvec4(1, 0, 0, 0);
+
 
 void
 initCamera(RenderState* rs, vec3 cam_pos, vec3 cam_focus, vec3 cam_up)
@@ -28,6 +32,22 @@ initCamera(RenderState* rs, vec3 cam_pos, vec3 cam_focus, vec3 cam_up)
 	assert(xform_ubo != nullptr);
 	updateGLBuffer(xform_ubo, &rs->camera->xforms);
 }
+void
+initLights(RenderState* rs)
+{
+	LightsBuffer* lb = rs->lights_buf;
+	u32 idx = 0;
+
+	// NOTE: add a directional light
+	idx = (*lb->active_d_lights)++;
+	lb->dl_directions[idx] = g_light_direction;
+	lb->dl_colors[idx] = g_light_color;
+	lb->dl_intensities[idx] = g_light_intensities;
+
+	GLBuffer* lights_ubo = getUBOByName(rs->gl_ctx, "lights");
+	assert(lights_ubo != nullptr);
+	updateGLBuffer(lights_ubo, lb->buffer);
+}
 
 Entity*
 initEllipseEntity(RenderState* rs,
@@ -59,32 +79,22 @@ initEllipseEntity(RenderState* rs,
 }
 
 Entity*
-initPlanetEntity(RenderState* rs)
+initPlanetEntity(RenderState* rs, double r)
 {
-	u32 num_vertices = 24;
-	vec3 vertex_color = vec3(255, 255, 0);
-	float radius = 3;
-
-	Mesh* m = meshInit(rs->rg_arena, num_vertices, num_vertices, false, true);
-	float angle = (float) M_PI * 2 / num_vertices;
-	float r = radius / SCALING;
-
-	for (uint i = 0; i < num_vertices; i++) {
-		m->vertices[i] = glm::vec3(cos(i * angle) * r, sin(i * angle) * r, 0);
-		m->colors[i] = vertex_color;
-		m->indices[i] = i;
-	}
-
-	Model* mdl = modelInitManual(rs->rg_arena, 1, m);
-	RenderGroup* rg = getRenderGroupByName(rs, "manual mesh group");
-	Entity* e = getFreeEntity(rg);
-	initEntity(e, rs->gl_ctx,
+	ShaderProgram* shader_lit = getShaderByName("full_lighting", rs->gl_ctx);
+	RenderGroup* rg_full = getFreeRenderGroup(rs);
+	initRenderGroup(rg_full, rs->rg_arena, shader_lit, 256, "lit group");
+	Model* icosphere = getModelByPath(&rs->assets, "../data/icosphere.gltf");
+	Entity* e = getFreeEntity(rg_full);
+	assert(icosphere && e);
+	initEntity(e,
+				rs->gl_ctx,
 				rs->rg_arena,
-				mdl,
-				rg->shader->num_vertex_attribs,
-				rg->shader->attrib_mappings,
-				"planet 01",
-				GL_LINE_LOOP);
+				icosphere,
+				shader_lit->num_vertex_attribs,
+				shader_lit->attrib_mappings,
+				"grav body 01");
+	scaleEntity(e, r);
 
 	return e;
 }
@@ -123,6 +133,7 @@ void
 loadScene(RenderState* rs)
 {
 	initCamera(rs, vec3(0, -75 / SCALING, 0), vec3(0, 0, 0), vec3(0,0,1));
+	initLights(rs);
 
 	double a = 26564.5;		// NOTE: semi-major axis in km
 	double e = 0.7411;		// NOTE: eccentricity
@@ -141,8 +152,7 @@ loadScene(RenderState* rs)
 	setEntityPosition(ellipse_entity, vec3(0, 0, 0));
 	rotateEntity(ellipse_entity, vec3(1, 0, 0), (float) M_PI / 2);
 
-	Entity* planet_entity = initPlanetEntity(rs);
-	rotateEntity(planet_entity, vec3(1, 0, 0), (float) M_PI / 2);
+	initPlanetEntity(rs, r);
 
 	Entity* satellite_entity = initSatelliteEntity(rs);
 	scaleEntity(satellite_entity, 1 / SCALING);