diff --git a/shaders/compiled/frag_rt_quad.spv b/shaders/compiled/frag_rt_quad.spv
index d3b4275..4b2eb61 100644
Binary files a/shaders/compiled/frag_rt_quad.spv and b/shaders/compiled/frag_rt_quad.spv differ
diff --git a/shaders/rt_quad.frag b/shaders/rt_quad.frag
index a7f8001..65f1bdd 100644
--- a/shaders/rt_quad.frag
+++ b/shaders/rt_quad.frag
@@ -34,6 +34,9 @@ int half_diffuse_raster_steps = int(scene_info.infos[2]);
 float raster_distance = uintBitsToFloat(scene_info.infos[3]);
 int raster_points = (2 * half_diffuse_raster_steps + 1) * (2 * half_diffuse_raster_steps + 1);
 float pos_infinity = uintBitsToFloat(0x7F800000);
+// set limit for maximal iterations
+uint max_iterations = max_num_lights * max_iterations_per_light * raster_points;
+uint iteration_num = 0;
 
 uvec4 unpack_color(uint val) {
     // left most 8 bits first
@@ -212,11 +215,10 @@ struct Tracing {
     bool has_transparent_hit;
 };
 
-Tracing trace_ray(uint volume_start, vec3 starting_pos, vec3 start_direction, float start_max_factor, uint start_cycle, uint max_cycle, bool allow_reflect) {
+Tracing trace_ray(uint volume_start, vec3 starting_pos, vec3 start_direction, float start_max_factor, bool allow_reflect) {
     vec3 direction = start_direction;
     float max_factor = start_max_factor;
     vec3 pos = starting_pos;
-    uint cycle = start_cycle;
     // setup volume info
     uint volume_index = volume_start;
     float volume_scale = uintBitsToFloat(scene_info.infos[volume_index + array_descr_offset + color_array_offset - 1]);
@@ -251,8 +253,8 @@ Tracing trace_ray(uint volume_start, vec3 starting_pos, vec3 start_direction, fl
     uvec2 end_raster_transparent;
     vec3 color_mul_transparent;
 
-    while (cycle < max_cycle) {
-        cycle ++;
+    while (iteration_num < max_iterations) {
+        iteration_num ++;
         float x_border = volume_pos_x + float((scene_info.infos[volume_index + 3]) * uint(x_pos)) * volume_scale - 0.5 * volume_scale;
         float y_border = volume_pos_y + float((scene_info.infos[volume_index + 4]) * uint(y_pos)) * volume_scale - 0.5 * volume_scale;
         float z_border = volume_pos_z + float((scene_info.infos[volume_index + 5]) * uint(z_pos)) * volume_scale - 0.5 * volume_scale;
@@ -370,8 +372,14 @@ Tracing trace_ray(uint volume_start, vec3 starting_pos, vec3 start_direction, fl
             }
         }
     }
+    /*if (iteration_num == max_iterations) {
+        end_color_transparent = uvec4(0, 0, 255, 255);
+        result.end_color = uvec4(0, 0, 255, 255);
+        result.color_mul = vec3(0.0, 0.0, 1.0);
+    }*/
+
     result.end_factor = min(min(x_factor, y_factor), z_factor);
-    result.end_cycle = cycle;
+    result.end_cycle = iteration_num;
 
     // in case we have a transparent hit but no hit afterwards
     if (!result.has_hit && result.has_transparent_hit) {
@@ -395,11 +403,9 @@ vec3 get_lighting_color(uint volume_start, vec3 starting_pos, vec4 orig_color_sa
     uint light_num = 0;
 
     // initialize color
-    vec3 color_sum = vec3(0.0, 0.0, 0.0) + (orig_color_sample.xyz * 0.005);
+    vec3 color_sum = vec3(0.0, 0.0, 0.0);// + (orig_color_sample.xyz * 0.005);
 
-    uint max_iterations = max_num_lights * max_iterations_per_light;
-    uint iteration = 0;
-    while (iteration < max_iterations) {
+    while (iteration_num < max_iterations) {
         // setup light info
         uint light_index = scene_info.infos[volume_start + 6 + light_num];
         if (light_index == 0) {
@@ -419,11 +425,12 @@ vec3 get_lighting_color(uint volume_start, vec3 starting_pos, vec4 orig_color_sa
         }
         vec3 light_color = get_light_color(light_index);
 
-        Tracing result = trace_ray(volume_start, starting_pos, light_direction, max_factor, iteration, max_iterations, false);
+        Tracing result = trace_ray(volume_start, starting_pos, light_direction, max_factor, false);
         // add result, if there is a hit the null vector will be added
         color_sum += float(!result.has_hit) * result.color_mul * max(dot(normal, normalize(light_direction)), 0.0) * (orig_color_sample.xyz * light_color) / (length(light_direction) * length(light_direction));
-        
-        iteration = result.end_cycle;
+        /*if (scene_info.infos[light_index] == 1) { 
+            color_sum = float(!result.has_hit) * result.color_mul;
+        }*/
 
         light_num += 1;
         if (light_num >= max_num_lights) {
@@ -487,7 +494,7 @@ vec3 add_reflection(vec3 view_vector, uint f, uint volume_start, vec3 pos, uvec4
     if (reflectivity > 0.01) {
         vec3 orig_color_sample = vec3(float(color_sample.x) / 255.0, float(color_sample.y) / 255.0, float(color_sample.z) / 255.0);
         vec3 reflection_direction = reflect_vector(view_vector, f);
-        Tracing reflection_tracing = trace_ray(volume_start, pos, reflection_direction, pos_infinity, 0, max_iterations_per_light, true);
+        Tracing reflection_tracing = trace_ray(volume_start, pos, reflection_direction, pos_infinity, true);
         if (reflection_tracing.has_hit || reflection_tracing.has_transparent_hit) {
             vec3 color_from_reflection = diffuse_tracing(reflection_tracing.end_volume, reflection_tracing.end_raster, reflection_tracing.end_pos, reflection_tracing.end_facing) * orig_color_sample;
             color_sum = color_sum * (1.0 - reflectivity) + color_from_reflection * reflectivity;
@@ -507,20 +514,21 @@ void main() {
     uint orig_neighbor = sample_neighbor_from_scene_info(fragVolumeStart, clamped_raster_pos, facing);
     if (orig_neighbor != 0) {
         vec3 color_direct = diffuse_tracing(fragVolumeStart, clamped_raster_pos, clamped_pos, facing);
-        color_direct = add_reflection(normalize(clamped_pos - ubo.camera_pos), facing, fragVolumeStart, clamped_pos, color_roughness, color_direct);
 
-        Tracing t = trace_ray(fragVolumeStart, ubo.camera_pos, clamped_pos - ubo.camera_pos, pos_infinity, 0, max_iterations_per_light, false);
+        Tracing t = trace_ray(fragVolumeStart, ubo.camera_pos, clamped_pos - ubo.camera_pos, pos_infinity, false);
         float opacity = float(color_roughness.w) / 255.0;
+        vec3 color_seen_through;
         if (t.has_hit) {
-            vec3 color_seen_through = diffuse_tracing(t.end_volume, t.end_raster, t.end_pos, t.end_facing) * orig_color_sample * t.color_mul;
+            color_seen_through = diffuse_tracing(t.end_volume, t.end_raster, t.end_pos, t.end_facing) * orig_color_sample * t.color_mul;
             color_seen_through = add_reflection(t.end_direction, t.end_facing, t.end_volume, t.end_pos, t.end_color, color_seen_through);
-
-            color_sum = opacity * color_direct + (1.0 - opacity) * color_seen_through;
         }
         else {
             // Todo: hit sky box
-            color_sum = opacity * color_direct + (1.0 - opacity) * vec3(0.0, 0.0, 0.0);
+            color_seen_through = vec3(0.0, 0.0, 0.0);
         }
+
+        color_direct = add_reflection(normalize(clamped_pos - ubo.camera_pos), facing, fragVolumeStart, clamped_pos, color_roughness, color_direct);
+        color_sum = opacity * color_direct + (1.0 - opacity) * color_seen_through;
     }
     else {
         color_sum = diffuse_tracing(fragVolumeStart, clamped_raster_pos, clamped_pos, facing);
diff --git a/src/main.rs b/src/main.rs
index 223503e..84a07ad 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -224,8 +224,8 @@ impl App {
         image::create_texture_image_view(&device, &mut data)?;
         image::create_texture_sampler(&device, &mut data)?;
         
-        //let cur_pos = generators::generate_test_scene(&mut scene_handler, &mut data)?;
-        let cur_pos = generators::generate_test_scene2(&mut scene_handler, &mut data, 31, 31,1, 5)?;
+        let cur_pos = generators::generate_test_scene(&mut scene_handler, &mut data)?;
+        //let cur_pos = generators::generate_test_scene2(&mut scene_handler, &mut data, 31, 31,1, 5)?;
         scene_handler.prepare_data(&instance, &device, &mut data)?;
 
         buffer::create_uniform_buffers(&instance, &device, &mut data)?;
diff --git a/src/scene/empty_volume.rs b/src/scene/empty_volume.rs
index 893cc92..b7f2cb9 100644
--- a/src/scene/empty_volume.rs
+++ b/src/scene/empty_volume.rs
@@ -553,16 +553,18 @@ impl EmptyVolume {
             let mut bottom_neighbors = vec![];
             let mut bottom_elements_num = 0;
             let mut all_same = true;
-            for x in 0..reference.borrow().size_x {
-                for y in 0..reference.borrow().size_y {
-                    if let Some(c) = neighbors.get_element(reference.borrow().grid_position.x + x, reference.borrow().grid_position.y + y, z_min_pos) {
-                        bottom_elements_num += 1;
-                        bottom_neighbors.push(Some(c.clone()));
-                        all_same = all_same && (bottom_neighbors[0] == Some(c));
-                    }
-                    else {
-                        bottom_neighbors.push(None);
-                        all_same = all_same && (bottom_neighbors[0] == None);
+            if reference.borrow().grid_position.z != 0 {
+                for x in 0..reference.borrow().size_x {
+                    for y in 0..reference.borrow().size_y {
+                        if let Some(c) = neighbors.get_element(reference.borrow().grid_position.x + x, reference.borrow().grid_position.y + y, z_min_pos) {
+                            bottom_elements_num += 1;
+                            bottom_neighbors.push(Some(c.clone()));
+                            all_same = all_same && (bottom_neighbors[0] == Some(c));
+                        }
+                        else {
+                            bottom_neighbors.push(None);
+                            all_same = all_same && (bottom_neighbors[0] == None);
+                        }
                     }
                 }
             }
@@ -639,16 +641,18 @@ impl EmptyVolume {
             let mut front_neighbors = vec![];
             let mut front_elements_num = 0;
             let mut all_same = true;
-            for x in 0..reference.borrow().size_x {
-                for z in 0..reference.borrow().size_z {
-                    if let Some(c) = neighbors.get_element(reference.borrow().grid_position.x + x, y_min_pos, reference.borrow().grid_position.z + z) {
-                        front_elements_num += 1;
-                        front_neighbors.push(Some(c.clone()));
-                        all_same = all_same && (front_neighbors[0] == Some(c));
-                    }
-                    else {
-                        front_neighbors.push(None);
-                        all_same = all_same && (front_neighbors[0] == None);
+            if reference.borrow().grid_position.y != 0 {
+                for x in 0..reference.borrow().size_x {
+                    for z in 0..reference.borrow().size_z {
+                        if let Some(c) = neighbors.get_element(reference.borrow().grid_position.x + x, y_min_pos, reference.borrow().grid_position.z + z) {
+                            front_elements_num += 1;
+                            front_neighbors.push(Some(c.clone()));
+                            all_same = all_same && (front_neighbors[0] == Some(c));
+                        }
+                        else {
+                            front_neighbors.push(None);
+                            all_same = all_same && (front_neighbors[0] == None);
+                        }
                     }
                 }
             }
@@ -668,16 +672,18 @@ impl EmptyVolume {
             let mut left_neighbors = vec![];
             let mut left_elements_num = 0;
             let mut all_same = true;
-            for y in 0..reference.borrow().size_y {
-                for z in 0..reference.borrow().size_z {
-                    if let Some(c) = neighbors.get_element(x_min_pos, reference.borrow().grid_position.y + y, reference.borrow().grid_position.z + z) {
-                        left_elements_num += 1;
-                        left_neighbors.push(Some(c.clone()));
-                        all_same = all_same && (left_neighbors[0] == Some(c));
-                    }
-                    else {
-                        left_neighbors.push(None);
-                        all_same = all_same && (left_neighbors[0] == None);
+            if reference.borrow().grid_position.x != 0 {
+                for y in 0..reference.borrow().size_y {
+                    for z in 0..reference.borrow().size_z {
+                        if let Some(c) = neighbors.get_element(x_min_pos, reference.borrow().grid_position.y + y, reference.borrow().grid_position.z + z) {
+                            left_elements_num += 1;
+                            left_neighbors.push(Some(c.clone()));
+                            all_same = all_same && (left_neighbors[0] == Some(c));
+                        }
+                        else {
+                            left_neighbors.push(None);
+                            all_same = all_same && (left_neighbors[0] == None);
+                        }
                     }
                 }
             }
diff --git a/src/scene/generators.rs b/src/scene/generators.rs
index c40c5da..9461344 100644
--- a/src/scene/generators.rs
+++ b/src/scene/generators.rs
@@ -58,8 +58,8 @@ pub fn generate_test_scene(scene: &mut Scene, data: &mut AppData) -> Result<(Poi
         pos: vec3(10.0, 10.0, 10.0),
         color: vec3(0.0, 0.0, 0.9),
         tex_coord: vec2(0.0, 0.0),
-        transparent: false,
-        roughness: 128,
+        transparent: true,
+        roughness: 32,
     };
     oct_tree1.set_cube(cube.clone());
 
@@ -67,8 +67,8 @@ pub fn generate_test_scene(scene: &mut Scene, data: &mut AppData) -> Result<(Poi
         pos: vec3(10.0, 10.0, 9.0),
         color: vec3(0.0, 0.0, 0.9),
         tex_coord: vec2(0.0, 0.0),
-        transparent: false,
-        roughness: 128,
+        transparent: true,
+        roughness: 32,
     };
     oct_tree1.set_cube(cube.clone());
 
@@ -91,7 +91,7 @@ pub fn generate_test_scene(scene: &mut Scene, data: &mut AppData) -> Result<(Poi
     };
     oct_tree2.set_cube(cube.clone());
 
-    scene.point_lights.push(Rc::new(RefCell::new(PointLight { pos: vec3(11.0 + grid_size as f32, 11.0 + grid_size as f32, 11.0) * scale, color: vec3(1.0, 1.0, 1.0), memory_start: 0 })));
+    scene.point_lights.push(Rc::new(RefCell::new(PointLight { pos: vec3(11.0 + grid_size as f32, 11.0 + grid_size as f32, 11.0) * scale, color: vec3(2.0, 2.0, 2.0), memory_start: 0 })));
     scene.point_lights.push(Rc::new(RefCell::new(PointLight { pos: vec3(9.0 + grid_size as f32, 9.0 + grid_size as f32, 11.0) * scale, color: vec3(0.5, 0.5, 0.5), memory_start: 0 })));
     scene.directional_lights.push(Rc::new(RefCell::new(DirectionalLight { direction: vec3(1.0, 1.0, -1.0), color: vec3(0.1, 0.1, 0.1), memory_start: 0 })));