diff --git a/src/engine/gl/texture.cpp b/src/engine/gl/texture.cpp
index 47291fa..cc4d3bb 100644
--- a/src/engine/gl/texture.cpp
+++ b/src/engine/gl/texture.cpp
@@ -331,7 +331,7 @@ void texture::resize(std::uint16_t width, std::uint16_t height, std::uint16_t de
 	/// @TODO: remove this
 	if (format == pixel_format::d)
 	{
-		glTexParameteri(m_gl_texture_target, GL_TEXTURE_COMPARE_FUNC, GL_LESS);
+		glTexParameteri(m_gl_texture_target, GL_TEXTURE_COMPARE_FUNC, GL_GREATER);
 		glTexParameteri(m_gl_texture_target, GL_TEXTURE_COMPARE_MODE, GL_COMPARE_REF_TO_TEXTURE);
 	}
 }
diff --git a/src/engine/math/matrix.hpp b/src/engine/math/matrix.hpp
index 52c165a..58b3143 100644
--- a/src/engine/math/matrix.hpp
+++ b/src/engine/math/matrix.hpp
@@ -584,7 +584,7 @@ template <class T, std::size_t N>
  * @return Viewing transformation matrix.
  */
 template <class T>
-[[nodiscard]] constexpr matrix<T, 4, 4> look_at(const vector<T, 3>& position, const vector<T, 3>& target, vector<T, 3> up);
+[[nodiscard]] constexpr mat4<T> look_at(const vec3<T>& position, const vec3<T>& target, vec3<T> up);
 
 /**
  * Multiplies two matrices
@@ -677,15 +677,14 @@ template <class T>
 [[nodiscard]] mat3<T> rotate_z(T angle);
 
 /**
- * Scales a matrix.
+ * Constructs a scale matrix.
  *
- * @param m Matrix to scale.
  * @param v Scale vector.
  *
- * @return Scaled matrix.
+ * @return Scale matrix.
  */
 template <class T>
-[[nodiscard]] constexpr matrix<T, 4, 4> scale(const matrix<T, 4, 4>& m, const vector<T, 3>& v);
+[[nodiscard]] constexpr mat4<T> scale(const vec3<T>& v);
 
 /**
  * Subtracts a matrix from another matrix.
@@ -731,15 +730,14 @@ template <class T, std::size_t N>
 [[nodiscard]] constexpr T trace(const matrix<T, N, N>& m) noexcept;
 
 /**
- * Translates a matrix.
+ * Constructs a translation matrix.
  *
- * @param m Matrix to translate.
  * @param v Translation vector.
  *
- * @return Translated matrix.
+ * @return Translation matrix.
  */
 template <class T>
-[[nodiscard]] constexpr matrix<T, 4, 4> translate(const matrix<T, 4, 4>& m, const vector<T, 3>& v);
+[[nodiscard]] constexpr mat4<T> translate(const vec3<T>& v);
 
 /**
  * Calculates the transpose of a matrix.
@@ -966,13 +964,12 @@ constexpr matrix<T, 4, 4> inverse(const matrix<T, 4, 4>& m) noexcept
 }
 
 template <class T>
-constexpr matrix<T, 4, 4> look_at(const vector<T, 3>& position, const vector<T, 3>& target, vector<T, 3> up)
+constexpr mat4<T> look_at(const vec3<T>& position, const vec3<T>& target, vec3<T> up)
 {
-	vector<T, 3> forward = normalize(sub(target, position));
-	vector<T, 3> right = normalize(cross(forward, up));
+	const auto forward = normalize(sub(target, position));
+	const auto right = normalize(cross(forward, up));
 	up = cross(right, forward);
-
-	matrix<T, 4, 4> m
+	const auto m = mat4<T>
 	{{
 		{right[0], up[0], -forward[0], T{0}},
 		{right[1], up[1], -forward[1], T{0}},
@@ -980,7 +977,7 @@ constexpr matrix<T, 4, 4> look_at(const vector<T, 3>& position, const vector<T,
 		{T{0}, T{0}, T{0}, T{1}}
 	}};
 	
-	return translate(m, negate(position));
+	return mul(m, translate(-position));
 }
 
 template <class T, std::size_t N, std::size_t M, std::size_t P>
@@ -1105,19 +1102,15 @@ mat3<T> rotate_z(T angle)
 }
 
 template <class T>
-constexpr matrix<T, 4, 4> scale(const matrix<T, 4, 4>& m, const vector<T, 3>& v)
+constexpr mat4<T> scale(const vec3<T>& v)
 {
-	return mul
-	(
-		m,
-		matrix<T, 4, 4>
-		{{
-			{v[0], T{0}, T{0}, T{0}},
-			{T{0}, v[1], T{0}, T{0}},
-			{T{0}, T{0}, v[2], T{0}},
-			{T{0}, T{0}, T{0}, T{1}}
-		}}
-	);
+	return
+	{{
+		{v[0], T{0}, T{0}, T{0}},
+		{T{0}, v[1], T{0}, T{0}},
+		{T{0}, T{0}, v[2], T{0}},
+		{T{0}, T{0}, T{0}, T{1}}
+	}};
 }
 
 /// @private
@@ -1173,15 +1166,15 @@ constexpr T trace(const matrix<T, N, N>& m) noexcept
 }
 
 template <class T>
-constexpr matrix<T, 4, 4> translate(const matrix<T, 4, 4>& m, const vector<T, 3>& v)
+constexpr mat4<T> translate(const vec3<T>& v)
 {
-	return mul(m, matrix<T, 4, 4>
+	return
 	{{
 		{T{1}, T{0}, T{0}, T{0}},
 		{T{0}, T{1}, T{0}, T{0}},
 		{T{0}, T{0}, T{1}, T{0}},
 		{v[0], v[1], v[2], T{1}}
-	}});
+	}};
 }
 
 /// @private
diff --git a/src/engine/physics/kinematics/collider.hpp b/src/engine/physics/kinematics/collider.hpp
index 101cf7c..1b54e29 100644
--- a/src/engine/physics/kinematics/collider.hpp
+++ b/src/engine/physics/kinematics/collider.hpp
@@ -41,7 +41,7 @@ public:
 	/**
 	 * Sets the layer mask of the collider.
 	 *
-	 * @param mask 32-bit layer mask in which each bit represents a layer with which the collider can interact.
+	 * @param mask 32-bit layer mask in which each set bit represents a layer with which the collider can interact.
 	 */
 	inline constexpr void set_layer_mask(std::uint32_t mask) noexcept
 	{
diff --git a/src/engine/render/context.hpp b/src/engine/render/context.hpp
index 6eb3c36..510a23f 100644
--- a/src/engine/render/context.hpp
+++ b/src/engine/render/context.hpp
@@ -42,7 +42,7 @@ struct context
 	const scene::camera* camera;
 	
 	/// Collection of scene objects being rendered.
-	const scene::collection* collection;
+	scene::collection* collection;
 	
 	/// Current time, in seconds.
 	float t;
diff --git a/src/engine/render/operation.hpp b/src/engine/render/operation.hpp
index 842ec78..81253b2 100644
--- a/src/engine/render/operation.hpp
+++ b/src/engine/render/operation.hpp
@@ -37,15 +37,17 @@ struct operation
 {
 	const gl::vertex_array* vertex_array{nullptr};
 	gl::drawing_mode drawing_mode{gl::drawing_mode::triangles};
-	std::size_t start_index{0};
-	std::size_t index_count{0};
+	std::size_t start_index{};
+	std::size_t index_count{};
 	std::shared_ptr<render::material> material;
 	
 	math::fmat4 transform{math::fmat4::identity()};
-	float depth{0.0f};
+	float depth{};
 	
-	std::size_t instance_count{0};
+	std::size_t instance_count{};
 	std::span<const math::fmat4> matrix_palette{};
+	
+	std::uint32_t layer_mask{};
 };
 
 } // namespace render
diff --git a/src/engine/render/passes/material-pass.cpp b/src/engine/render/passes/material-pass.cpp
index 3960253..d2e1e4a 100644
--- a/src/engine/render/passes/material-pass.cpp
+++ b/src/engine/render/passes/material-pass.cpp
@@ -95,20 +95,27 @@ bool operation_compare(const render::operation* a, const render::operation* b)
 		}
 		else
 		{
-			// A and B are both opaque
-			
+			// A and B are both opaque, sort by material hash
 			const std::size_t hash_a = a->material->hash();
 			const std::size_t hash_b = b->material->hash();
 			
-			if (hash_a == hash_b)
+			if (hash_a != hash_b)
 			{
-				// A and B have same material hash, sort by VAO
-				return (a->vertex_array < b->vertex_array);
+				// A and B have different material hashes, sort by hash
+				return (hash_a < hash_b);
 			}
 			else
 			{
-				// A and B have different material hashes, sort by hash
-				return (hash_a < hash_b);
+				// A and B have the same material hash, sort by layer mask
+				if (a->layer_mask != b->layer_mask)
+				{
+					return (a->layer_mask < b->layer_mask);
+				}
+				else
+				{
+					// A and B have the same layer mask, sort by VAO
+					return (a->vertex_array < b->vertex_array);
+				}
 			}
 		}
 	}
@@ -152,10 +159,11 @@ void material_pass::render(render::context& ctx)
 	material_blend_mode active_blend_mode = material_blend_mode::opaque;
 	std::size_t active_cache_key = 0;
 	shader_cache_entry* active_cache_entry = nullptr;
+	std::uint32_t active_layer_mask = 0;
+	std::size_t active_lighting_state_hash = 0;
 	
 	// Gather information
 	evaluate_camera(ctx);
-	evaluate_lighting(ctx);
 	evaluate_misc(ctx);
 	
 	// Sort render operations
@@ -177,13 +185,20 @@ void material_pass::render(render::context& ctx)
 			material = fallback_material.get();
 		}
 		
+		// Evaluate visible lights
+		if (active_layer_mask != operation->layer_mask)
+		{
+			evaluate_lighting(ctx, operation->layer_mask & ctx.camera->get_layer_mask());
+			active_layer_mask = operation->layer_mask;
+		}
+		
 		// Switch materials if necessary
-		if (active_material != material)
+		if (active_material != material || active_lighting_state_hash != lighting_state_hash)
 		{
-			if (!material->get_shader_template())
-			{
-				continue;
-			}
+			// if (!material->get_shader_template())
+			// {
+				// continue;
+			// }
 			
 			if (active_material_hash != material->hash())
 			{
@@ -271,6 +286,7 @@ void material_pass::render(render::context& ctx)
 			}
 			
 			active_material = material;
+			active_lighting_state_hash = lighting_state_hash;
 		}
 		
 		// Update geometry-dependent shader variables
@@ -315,7 +331,7 @@ void material_pass::evaluate_camera(const render::context& ctx)
 	log_depth_coef = 2.0f / std::log2(clip_depth[1] + 1.0f);
 }
 
-void material_pass::evaluate_lighting(const render::context& ctx)
+void material_pass::evaluate_lighting(const render::context& ctx, std::uint32_t layer_mask)
 {
 	// Reset light and shadow counts
 	light_probe_count = 0;
@@ -328,6 +344,11 @@ void material_pass::evaluate_lighting(const render::context& ctx)
 	const auto& light_probes = ctx.collection->get_objects(scene::light_probe::object_type_id);
 	for (const scene::object_base* object: light_probes)
 	{
+		if (!(object->get_layer_mask() & layer_mask))
+		{
+			continue;
+		}
+		
 		if (!light_probe_count)
 		{
 			const scene::light_probe& light_probe = static_cast<const scene::light_probe&>(*object);
@@ -340,6 +361,11 @@ void material_pass::evaluate_lighting(const render::context& ctx)
 	const auto& lights = ctx.collection->get_objects(scene::light::object_type_id);
 	for (const scene::object_base* object: lights)
 	{
+		if (!(object->get_layer_mask() & layer_mask))
+		{
+			continue;
+		}
+		
 		const scene::light& light = static_cast<const scene::light&>(*object);
 		
 		switch (light.get_light_type())
@@ -370,15 +396,13 @@ void material_pass::evaluate_lighting(const render::context& ctx)
 					if (directional_shadow_count > directional_shadow_maps.size())
 					{
 						directional_shadow_maps.resize(directional_shadow_count);
-						directional_shadow_biases.resize(directional_shadow_count);
 						directional_shadow_splits.resize(directional_shadow_count);
 						directional_shadow_matrices.resize(directional_shadow_count);
 					}
 					
 					directional_shadow_maps[index] = static_cast<const gl::texture_2d*>(directional_light.get_shadow_framebuffer()->get_depth_attachment());
-					directional_shadow_biases[index] = directional_light.get_shadow_bias();
-					directional_shadow_splits[index] = &directional_light.get_shadow_cascade_distances();
-					directional_shadow_matrices[index] = &directional_light.get_shadow_cascade_matrices();
+					directional_shadow_splits[index] = directional_light.get_shadow_cascade_distances();
+					directional_shadow_matrices[index] = directional_light.get_shadow_cascade_matrices();
 				}
 				break;
 			}
@@ -659,25 +683,23 @@ void material_pass::build_shader_command_buffer(std::vector<std::function<void()
 	{
 		if (auto directional_shadow_maps_var = shader_program.variable("directional_shadow_maps"))
 		{
-			auto directional_shadow_biases_var = shader_program.variable("directional_shadow_biases");
 			auto directional_shadow_splits_var = shader_program.variable("directional_shadow_splits");
 			auto directional_shadow_matrices_var = shader_program.variable("directional_shadow_matrices");
 			
-			if (directional_shadow_maps_var && directional_shadow_biases_var && directional_shadow_splits_var && directional_shadow_matrices_var)
+			if (directional_shadow_maps_var && directional_shadow_splits_var && directional_shadow_matrices_var)
 			{
 				command_buffer.emplace_back
 				(
-					[&, directional_shadow_maps_var, directional_shadow_biases_var, directional_shadow_splits_var, directional_shadow_matrices_var]()
+					[&, directional_shadow_maps_var, directional_shadow_splits_var, directional_shadow_matrices_var]()
 					{
 						directional_shadow_maps_var->update(std::span<const gl::texture_2d* const>{directional_shadow_maps.data(), directional_shadow_count});
-						directional_shadow_biases_var->update(std::span<const float>{directional_shadow_biases.data(), directional_shadow_count});
 						
 						std::size_t offset = 0;
 						for (std::size_t i = 0; i < directional_shadow_count; ++i)
 						{
-							directional_shadow_splits_var->update(*directional_shadow_splits[i], offset * 4);
-							directional_shadow_matrices_var->update(*directional_shadow_matrices[i], offset);
-							offset += directional_shadow_splits[i]->size();
+							directional_shadow_splits_var->update(directional_shadow_splits[i], offset * 4);
+							directional_shadow_matrices_var->update(directional_shadow_matrices[i], offset);
+							offset += directional_shadow_splits[i].size();
 						}
 					}
 				);
diff --git a/src/engine/render/passes/material-pass.hpp b/src/engine/render/passes/material-pass.hpp
index 6e459cf..b9abeba 100644
--- a/src/engine/render/passes/material-pass.hpp
+++ b/src/engine/render/passes/material-pass.hpp
@@ -79,7 +79,7 @@ private:
 	/**
 	 * Evaluates scene lights and stores lighting information in local variables to be passed to shaders.
 	 */
-	void evaluate_lighting(const render::context& ctx);
+	void evaluate_lighting(const render::context& ctx, std::uint32_t layer_mask);
 	
 	void evaluate_misc(const render::context& ctx);
 	
@@ -115,9 +115,8 @@ private:
 	
 	// Directional shadows
 	std::vector<const gl::texture_2d*> directional_shadow_maps;
-	std::vector<float> directional_shadow_biases;
-	std::vector<const std::vector<float>*> directional_shadow_splits;
-	std::vector<const std::vector<math::fmat4>*> directional_shadow_matrices;
+	std::vector<std::span<const float>> directional_shadow_splits;
+	std::vector<std::span<const math::fmat4>> directional_shadow_matrices;
 	std::size_t directional_shadow_count;
 	
 	// Spot lights
diff --git a/src/engine/render/passes/shadow-map-pass.cpp b/src/engine/render/passes/shadow-map-pass.cpp
index 869f7b8..539984e 100644
--- a/src/engine/render/passes/shadow-map-pass.cpp
+++ b/src/engine/render/passes/shadow-map-pass.cpp
@@ -25,12 +25,12 @@
 #include <engine/gl/drawing-mode.hpp>
 #include <engine/render/context.hpp>
 #include <engine/render/material.hpp>
+#include <engine/render/vertex-attribute.hpp>
 #include <engine/gl/shader-template.hpp>
 #include <engine/scene/camera.hpp>
 #include <engine/scene/collection.hpp>
 #include <engine/scene/light.hpp>
 #include <engine/geom/primitives/view-frustum.hpp>
-#include <engine/config.hpp>
 #include <engine/math/interpolation.hpp>
 #include <engine/math/vector.hpp>
 #include <engine/math/matrix.hpp>
@@ -47,54 +47,65 @@ static bool operation_compare(const render::operation* a, const render::operatio
 shadow_map_pass::shadow_map_pass(gl::rasterizer* rasterizer, resource_manager* resource_manager):
 	pass(rasterizer, nullptr)
 {
+	std::unordered_map<std::string, std::string> definitions;
+	definitions["VERTEX_POSITION"]    = std::to_string(vertex_attribute::position);
+	definitions["VERTEX_UV"]          = std::to_string(vertex_attribute::uv);
+	definitions["VERTEX_NORMAL"]      = std::to_string(vertex_attribute::normal);
+	definitions["VERTEX_TANGENT"]     = std::to_string(vertex_attribute::tangent);
+	definitions["VERTEX_COLOR"]       = std::to_string(vertex_attribute::color);
+	definitions["VERTEX_BONE_INDEX"]  = std::to_string(vertex_attribute::bone_index);
+	definitions["VERTEX_BONE_WEIGHT"] = std::to_string(vertex_attribute::bone_weight);
+	definitions["VERTEX_BONE_WEIGHT"] = std::to_string(vertex_attribute::bone_weight);
+	definitions["MAX_BONE_COUNT"] = std::to_string(64);
+	
 	// Load unskinned shader template
 	auto unskinned_shader_template = resource_manager->load<gl::shader_template>("depth-unskinned.glsl");
 	
 	// Build unskinned shader program
-	unskinned_shader_program = unskinned_shader_template->build({});
+	unskinned_shader_program = unskinned_shader_template->build(definitions);
+	if (!unskinned_shader_program->linked())
+	{
+		debug::log::error("Failed to build unskinned shadow map shader program: {}", unskinned_shader_program->info());
+		debug::log::warning("{}", unskinned_shader_template->configure(gl::shader_stage::vertex));
+	}
 	unskinned_model_view_projection_var = unskinned_shader_program->variable("model_view_projection");
 	
 	// Load skinned shader template
 	auto skinned_shader_template = resource_manager->load<gl::shader_template>("depth-skinned.glsl");
 	
 	// Build skinned shader program
-	skinned_shader_program = skinned_shader_template->build({});
-	skinned_model_view_projection_var = skinned_shader_program->variable("model_view_projection");
-	
-	// Calculate bias-tile matrices
-	math::fmat4 bias_matrix = math::translate(math::fmat4::identity(), math::fvec3{0.5f, 0.5f, 0.5f}) * math::scale(math::fmat4::identity(), math::fvec3{0.5f, 0.5f, 0.5f});
-	math::fmat4 tile_scale = math::scale(math::fmat4::identity(), math::fvec3{0.5f, 0.5f, 1.0f});
-	for (int i = 0; i < 4; ++i)
+	skinned_shader_program = skinned_shader_template->build(definitions);
+	if (!skinned_shader_program->linked())
 	{
-		float x = static_cast<float>(i % 2) * 0.5f;
-		float y = static_cast<float>(i / 2) * 0.5f;
-		math::fmat4 tile_matrix = math::translate(math::fmat4::identity(), math::fvec3{x, y, 0.0f}) * tile_scale;
-		bias_tile_matrices[i] = tile_matrix * bias_matrix;
+		debug::log::error("Failed to build skinned shadow map shader program: {}", skinned_shader_program->info());
+		debug::log::warning("{}", skinned_shader_template->configure(gl::shader_stage::vertex));
 	}
+	skinned_model_view_projection_var = skinned_shader_program->variable("model_view_projection");
+	skinned_matrix_palette_var = skinned_shader_program->variable("matrix_palette");
 }
 
 void shadow_map_pass::render(render::context& ctx)
 {
 	// For each light
 	const auto& lights = ctx.collection->get_objects(scene::light::object_type_id);
-	for (const scene::object_base* object: lights)
+	for (scene::object_base* object: lights)
 	{
 		// Ignore non-directional lights
-		const scene::light& light = static_cast<const scene::light&>(*object);
+		auto& light = static_cast<scene::light&>(*object);
 		if (light.get_light_type() != scene::light_type::directional)
 		{
 			continue;
 		}
 		
 		// Ignore non-shadow casters
-		const scene::directional_light& directional_light = static_cast<const scene::directional_light&>(light);
+		auto& directional_light = static_cast<scene::directional_light&>(light);
 		if (!directional_light.is_shadow_caster())
 		{
 			continue;
 		}
 		
 		// Ignore improperly-configured lights
-		if (!directional_light.get_shadow_cascade_count() || !directional_light.get_shadow_framebuffer())
+		if (!directional_light.get_shadow_framebuffer() || !directional_light.get_shadow_cascade_count())
 		{
 			continue;
 		}
@@ -104,8 +115,16 @@ void shadow_map_pass::render(render::context& ctx)
 	}
 }
 
-void shadow_map_pass::render_csm(const scene::directional_light& light, render::context& ctx)
+void shadow_map_pass::render_csm(scene::directional_light& light, render::context& ctx)
 {
+	// Get light layer mask
+	const auto light_layer_mask = light.get_layer_mask();
+	
+	if (!light_layer_mask & ctx.camera->get_layer_mask())
+	{
+		return;
+	}
+	
 	rasterizer->use_framebuffer(*light.get_shadow_framebuffer());
 	
 	// Disable blending
@@ -113,7 +132,7 @@ void shadow_map_pass::render_csm(const scene::directional_light& light, render::
 	
 	// Enable depth testing
 	glEnable(GL_DEPTH_TEST);
-	glDepthFunc(GL_LESS);
+	glDepthFunc(GL_GREATER);
 	glDepthMask(GL_TRUE);
 	
 	// Enable back-face culling
@@ -124,17 +143,18 @@ void shadow_map_pass::render_csm(const scene::directional_light& light, render::
 	// For half-z buffer
 	glDepthRange(-1.0f, 1.0f);
 	
+
+	
 	// Get camera
 	const scene::camera& camera = *ctx.camera;
 	
 	// Calculate distance to shadow cascade depth clipping planes
 	const float shadow_clip_far = math::lerp(camera.get_clip_near(), camera.get_clip_far(), light.get_shadow_cascade_coverage());
 	
-	const unsigned int cascade_count = light.get_shadow_cascade_count();
-	
-	/// @TODO: don't const_cast
-	auto& cascade_distances = const_cast<std::vector<float>&>(light.get_shadow_cascade_distances());
-	auto& cascade_matrices = const_cast<std::vector<math::fmat4>&>(light.get_shadow_cascade_matrices());
+	// Get light shadow cascade distances and matrices
+	const auto cascade_count = light.get_shadow_cascade_count();
+	const auto cascade_distances = light.get_shadow_cascade_distances();
+	const auto cascade_matrices = light.get_shadow_cascade_matrices();
 	
 	// Calculate cascade far clipping plane distances
 	cascade_distances[cascade_count - 1] = shadow_clip_far;
@@ -166,101 +186,76 @@ void shadow_map_pass::render_csm(const scene::directional_light& light, render::
 		viewport[3] = cascade_resolution;
 	}
 	
-	// Reverse half z clip-space coordinates of a cube
-	constexpr math::fvec4 clip_space_cube[8] =
-	{
-		{-1, -1, 1, 1}, // NBL
-		{ 1, -1, 1, 1}, // NBR
-		{-1,  1, 1, 1}, // NTL
-		{ 1,  1, 1, 1}, // NTR
-		{-1, -1, 0, 1}, // FBL
-		{ 1, -1, 0, 1}, // FBR
-		{-1,  1, 0, 1}, // FTL
-		{ 1,  1, 0, 1}  // FTR
-	};
-	
-	// Calculate world-space corners of camera view frustum
-	math::fvec3 view_frustum_corners[8];
-	for (std::size_t i = 0; i < 8; ++i)
-	{
-		math::fvec4 corner = camera.get_inverse_view_projection() * clip_space_cube[i];
-		view_frustum_corners[i] = math::fvec3(corner) / corner[3];
-	}
-	
 	// Sort render operations
 	std::sort(std::execution::par_unseq, ctx.operations.begin(), ctx.operations.end(), operation_compare);
 	
 	gl::shader_program* active_shader_program = nullptr;
 	
+	// Precalculate frustum minimal bounding sphere terms
+	const auto k = std::sqrt(1.0f + camera.get_aspect_ratio() * camera.get_aspect_ratio()) * std::tan(camera.get_vertical_fov() * 0.5f);
+	const auto k2 = k * k;
+	const auto k4 = k2 * k2;
+	
 	for (unsigned int i = 0; i < cascade_count; ++i)
 	{
 		// Set viewport for this shadow map
 		const math::ivec4& viewport = shadow_map_viewports[i];
 		rasterizer->set_viewport(viewport[0], viewport[1], viewport[2], viewport[3]);
 		
-		// Calculate world-space corners and center of camera subfrustum
-		const float t_near = (i) ? cascade_distances[i - 1] / camera.get_clip_far() : 0.0f;
-		const float t_far = cascade_distances[i] / camera.get_clip_far();
-		math::fvec3 subfrustum_center{0, 0, 0};
-		math::fvec3 subfrustum_corners[8];
-		for (std::size_t i = 0; i < 4; ++i)
+		// Find minimal bounding sphere of subfrustum in view-space
+		// @see https://lxjk.github.io/2017/04/15/Calculate-Minimal-Bounding-Sphere-of-Frustum.html
+		geom::sphere<float> subfrustum_bounds;
 		{
-			subfrustum_corners[i] = math::lerp(view_frustum_corners[i], view_frustum_corners[i + 4], t_near);
-			subfrustum_corners[i + 4] = math::lerp(view_frustum_corners[i], view_frustum_corners[i + 4], t_far);
+			// Get subfrustum near and far distances
+			const auto n = (i) ? cascade_distances[i - 1] : camera.get_clip_near();
+			const auto f = cascade_distances[i];
 			
-			subfrustum_center += subfrustum_corners[i];
-			subfrustum_center += subfrustum_corners[i + 4];
+			if (k2 >= (f - n) / (f + n))
+			{
+				subfrustum_bounds.center = {0, 0, -f};
+				subfrustum_bounds.radius = f * k;
+			}
+			else
+			{
+				subfrustum_bounds.center = {0, 0, -0.5f * (f + n) * (1.0f + k2)};
+				subfrustum_bounds.radius = 0.5f * std::sqrt((k4 + 2.0f * k2 + 1.0f) * (f * f + n * n) + 2.0f * f * (k4 - 1.0f) * n);
+			}
 		}
-		subfrustum_center *= (1.0f / 8.0f);
 		
-		// Calculate a view-projection matrix from the light's point-of-view
-		const math::fvec3 light_up = light.get_rotation() * config::global_up;
-		math::fmat4 light_view = math::look_at(subfrustum_center, subfrustum_center + light.get_direction(), light_up);
-		math::fmat4 light_projection = math::ortho(-1.0f, 1.0f, -1.0f, 1.0f, -1.0f, 1.0f);
-		math::fmat4 light_view_projection = light_projection * light_view;
+		// Transform subfrustum bounds into world-space
+		subfrustum_bounds.center = camera.get_translation() + camera.get_rotation() * subfrustum_bounds.center;
 		
-		// Calculate AABB of the subfrustum corners in light clip-space
-		geom::box<float> cropping_bounds = {math::fvec3::infinity(), -math::fvec3::infinity()};
-		for (std::size_t i = 0; i < 8; ++i)
-		{
-			math::fvec4 corner4 = math::fvec4(subfrustum_corners[i]);
-			corner4[3] = 1.0f;
-			corner4 = light_view_projection * corner4;
-			
-			const math::fvec3 corner3 = math::fvec3(corner4) / corner4[3];
-			
-			cropping_bounds.min = math::min(cropping_bounds.min, corner3);
-			cropping_bounds.max = math::max(cropping_bounds.max, corner3);
-		}
+		// Discretize view-space subfrustum bounds
+		const auto texel_scale = static_cast<float>(cascade_resolution) / (subfrustum_bounds.radius * 2.0f);
+		subfrustum_bounds.center = math::conjugate(light.get_rotation()) * subfrustum_bounds.center;
+		subfrustum_bounds.center = math::floor(subfrustum_bounds.center * texel_scale) / texel_scale;
+		subfrustum_bounds.center = light.get_rotation() * subfrustum_bounds.center;
 		
-		// Quantize clip-space coordinates
-		const float texel_scale_x = (cropping_bounds.max.x() - cropping_bounds.min.x()) / static_cast<float>(cascade_resolution);
-		const float texel_scale_y = (cropping_bounds.max.y() - cropping_bounds.min.y()) / static_cast<float>(cascade_resolution);
-		cropping_bounds.min.x() = std::floor(cropping_bounds.min.x() / texel_scale_x) * texel_scale_x;
-		cropping_bounds.max.x() = std::floor(cropping_bounds.max.x() / texel_scale_x) * texel_scale_x;
-		cropping_bounds.min.y() = std::floor(cropping_bounds.min.y() / texel_scale_y) * texel_scale_y;
-		cropping_bounds.max.y() = std::floor(cropping_bounds.max.y() / texel_scale_y) * texel_scale_y;
+		// Construct light view matrix
+		const auto light_view = math::look_at(subfrustum_bounds.center, subfrustum_bounds.center + light.get_direction(), light.get_rotation() * math::fvec3{0, 1, 0});
 		
-		/// @NOTE: light z should be modified here to included shadow casters outside the view frustum
-		// cropping_bounds.min.z() -= 10.0f;
-		// cropping_bounds.max.z() += 10.0f;
-		
-		// Crop light projection matrix
-		light_projection = math::ortho_half_z
+		// Construct light projection matrix (reversed half-z)
+		const auto light_projection = math::ortho_half_z
 		(
-			cropping_bounds.min.x(), cropping_bounds.max.x(),
-			cropping_bounds.min.y(), cropping_bounds.max.y(),
-			cropping_bounds.min.z(), cropping_bounds.max.z()
+			-subfrustum_bounds.radius, subfrustum_bounds.radius,
+			-subfrustum_bounds.radius, subfrustum_bounds.radius,
+			subfrustum_bounds.radius, -subfrustum_bounds.radius
 		);
 		
-		// Recalculate light view projection matrix
-		light_view_projection = light_projection * light_view;
+		// Construct light view-projection matrix
+		const auto light_view_projection = light_projection * light_view;
 		
-		// Calculate world-space to cascade texture-space transformation matrix
-		cascade_matrices[i] = bias_tile_matrices[i] * light_view_projection;
+		// Update world-space to cascade texture-space transformation matrix
+		cascade_matrices[i] = light.get_shadow_bias_scale_matrices()[i] * light_view_projection;
 		
 		for (const render::operation* operation: ctx.operations)
 		{
+			// Skip operations which don't share any layers with the shadow-casting light
+			if (!(operation->layer_mask & light_layer_mask))
+			{
+				continue;
+			}
+			
 			const render::material* material = operation->material.get();
 			if (material)
 			{
@@ -304,6 +299,7 @@ void shadow_map_pass::render_csm(const scene::directional_light& light, render::
 			else if (active_shader_program == skinned_shader_program.get())
 			{
 				skinned_model_view_projection_var->update(model_view_projection);
+				skinned_matrix_palette_var->update(operation->matrix_palette);
 			}
 
 			// Draw geometry
diff --git a/src/engine/render/passes/shadow-map-pass.hpp b/src/engine/render/passes/shadow-map-pass.hpp
index 943b94b..3cbc172 100644
--- a/src/engine/render/passes/shadow-map-pass.hpp
+++ b/src/engine/render/passes/shadow-map-pass.hpp
@@ -62,15 +62,14 @@ private:
 	 * @param ctx Render context.
 	 * @param queue Render queue.
 	 */
-	void render_csm(const scene::directional_light& light, render::context& ctx);
+	void render_csm(scene::directional_light& light, render::context& ctx);
 	
 	std::unique_ptr<gl::shader_program> unskinned_shader_program;
 	const gl::shader_variable* unskinned_model_view_projection_var;
 	
 	std::unique_ptr<gl::shader_program> skinned_shader_program;
 	const gl::shader_variable* skinned_model_view_projection_var;
-	
-	math::fmat4 bias_tile_matrices[4];
+	const gl::shader_variable* skinned_matrix_palette_var;
 };
 
 } // namespace render
diff --git a/src/engine/render/passes/sky-pass.cpp b/src/engine/render/passes/sky-pass.cpp
index 5b7ec3a..cfee738 100644
--- a/src/engine/render/passes/sky-pass.cpp
+++ b/src/engine/render/passes/sky-pass.cpp
@@ -188,6 +188,11 @@ sky_pass::sky_pass(gl::rasterizer* rasterizer, const gl::framebuffer* framebuffe
 
 void sky_pass::render(render::context& ctx)
 {
+	if (!(m_layer_mask & ctx.camera->get_layer_mask()))
+	{
+		return;
+	}
+	
 	glDisable(GL_BLEND);
 	glDisable(GL_DEPTH_TEST);
 	glDepthMask(GL_FALSE);
@@ -219,7 +224,7 @@ void sky_pass::render(render::context& ctx)
 	// Construct matrices
 	const scene::camera& camera = *ctx.camera;
 	math::fvec3 model_scale = math::fvec3{1.0f, 1.0f, 1.0f} * (camera.get_clip_near() + camera.get_clip_far()) * 0.5f;
-	math::fmat4 model = math::scale(math::fmat4::identity(), model_scale);
+	math::fmat4 model = math::scale(model_scale);
 	math::fmat4 view = math::fmat4(math::fmat3(camera.get_view()));
 	math::fmat4 model_view = view * model;
 	const math::fmat4& projection = camera.get_projection();
@@ -387,8 +392,7 @@ void sky_pass::render(render::context& ctx)
 	{
 		float star_distance = (camera.get_clip_near() + camera.get_clip_far()) * 0.5f;
 		
-		model = math::fmat4(math::fmat3(icrf_to_eus.r));
-		model = math::scale(model, {star_distance, star_distance, star_distance});
+		model = math::fmat4(math::fmat3(icrf_to_eus.r)) * math::scale(math::fvec3{star_distance, star_distance, star_distance});
 		
 		model_view_projection = view_projection * model;
 		
diff --git a/src/engine/render/passes/sky-pass.hpp b/src/engine/render/passes/sky-pass.hpp
index 3d6a51c..efe6376 100644
--- a/src/engine/render/passes/sky-pass.hpp
+++ b/src/engine/render/passes/sky-pass.hpp
@@ -211,6 +211,16 @@ public:
 
 	
 	void set_sky_probe(std::shared_ptr<scene::light_probe> probe);
+	
+	/**
+	 * Sets the layer mask of the sky.
+	 *
+	 * @param mask 32-bit layer mask in which each set bit represents a layer in which the sky is visible.
+	 */
+	inline constexpr void set_layer_mask(std::uint32_t mask) noexcept
+	{
+		m_layer_mask = mask;
+	}
 
 private:
 	void rebuild_transmittance_lut_shader_program();
@@ -358,6 +368,8 @@ private:
 	math::fvec3 m_ground_albedo{};
 	
 	float magnification;
+	
+	std::uint32_t m_layer_mask{1};
 };
 
 } // namespace render
diff --git a/src/engine/render/renderer.cpp b/src/engine/render/renderer.cpp
index 46add24..8f69341 100644
--- a/src/engine/render/renderer.cpp
+++ b/src/engine/render/renderer.cpp
@@ -45,7 +45,7 @@ renderer::renderer(gl::rasterizer& rasterizer, ::resource_manager& resource_mana
 	m_queue_stage = std::make_unique<render::queue_stage>();
 }
 
-void renderer::render(float t, float dt, float alpha, const scene::collection& collection)
+void renderer::render(float t, float dt, float alpha, scene::collection& collection)
 {
 	// Init render context
 	m_ctx.collection = &collection;
diff --git a/src/engine/render/renderer.hpp b/src/engine/render/renderer.hpp
index 901f320..2eafff2 100644
--- a/src/engine/render/renderer.hpp
+++ b/src/engine/render/renderer.hpp
@@ -53,7 +53,7 @@ public:
 	 * @param alpha Subframe interpolation factor.
 	 * @param collection Collection of scene objects to render.
 	 */
-	void render(float t, float dt, float alpha, const scene::collection& collection);
+	void render(float t, float dt, float alpha, scene::collection& collection);
 	
 private:
 	render::context m_ctx;
diff --git a/src/engine/render/stages/culling-stage.cpp b/src/engine/render/stages/culling-stage.cpp
index bab656e..e5be4eb 100644
--- a/src/engine/render/stages/culling-stage.cpp
+++ b/src/engine/render/stages/culling-stage.cpp
@@ -31,7 +31,8 @@ void culling_stage::execute(render::context& ctx)
 	// Get all objects in the collection
 	const auto& objects = ctx.collection->get_objects();
 	
-	// Get camera view frustum
+	// Get camera layer mask and view frustum
+	const auto camera_layer_mask = ctx.camera->get_layer_mask();
 	const auto& view_frustum = ctx.camera->get_view_frustum();
 	
 	// Construct mutex to guard set of visible objects
@@ -52,8 +53,10 @@ void culling_stage::execute(render::context& ctx)
 			}
 			
 			// Cull object if it doesn't share any common layers with the camera
-			//if (!(object->get_layer_mask() & camera_layer_mask))
-			//	return;
+			if (!(object->get_layer_mask() & camera_layer_mask))
+			{
+				return;
+			}
 			
 			// Cull object if it's outside of the camera view frustum
 			if (!view_frustum.intersects(object->get_bounds()))
diff --git a/src/engine/scene/billboard.cpp b/src/engine/scene/billboard.cpp
index 482bda8..1887d80 100644
--- a/src/engine/scene/billboard.cpp
+++ b/src/engine/scene/billboard.cpp
@@ -125,6 +125,7 @@ void billboard::render(render::context& ctx) const
 	}
 	
 	m_render_op.depth = ctx.camera->get_view_frustum().near().distance(get_translation());
+	m_render_op.layer_mask = get_layer_mask();
 	
 	ctx.operations.emplace_back(&m_render_op);
 }
diff --git a/src/engine/scene/directional-light.cpp b/src/engine/scene/directional-light.cpp
index caa0c77..5b21563 100644
--- a/src/engine/scene/directional-light.cpp
+++ b/src/engine/scene/directional-light.cpp
@@ -23,8 +23,11 @@ namespace scene {
 
 directional_light::directional_light():
 	m_shadow_cascade_distances(m_shadow_cascade_count),
-	m_shadow_cascade_matrices(m_shadow_cascade_count)
-{}
+	m_shadow_cascade_matrices(m_shadow_cascade_count),
+	m_shadow_bias_scale_matrices(m_shadow_cascade_count)
+{
+	set_shadow_bias(m_shadow_bias);
+}
 
 void directional_light::set_direction(const math::fvec3& direction)
 {
@@ -44,6 +47,7 @@ void directional_light::set_shadow_framebuffer(std::shared_ptr<gl::framebuffer>
 void directional_light::set_shadow_bias(float bias) noexcept
 {
 	m_shadow_bias = bias;
+	update_shadow_bias_scale_matrices();
 }
 
 void directional_light::set_shadow_cascade_count(unsigned int count) noexcept
@@ -51,6 +55,8 @@ void directional_light::set_shadow_cascade_count(unsigned int count) noexcept
 	m_shadow_cascade_count = count;
 	m_shadow_cascade_distances.resize(m_shadow_cascade_count);
 	m_shadow_cascade_matrices.resize(m_shadow_cascade_count);
+	m_shadow_bias_scale_matrices.resize(m_shadow_cascade_count);
+	update_shadow_bias_scale_matrices();
 }
 
 void directional_light::set_shadow_cascade_coverage(float factor) noexcept
@@ -78,4 +84,19 @@ void directional_light::illuminance_updated()
 	m_colored_illuminance = m_color * m_illuminance;
 }
 
+void directional_light::update_shadow_bias_scale_matrices()
+{
+	// Construct shadow bias-scale matrix
+	auto m = math::translate(math::fvec3{0.5f, 0.5f, 0.5f + m_shadow_bias}) * math::scale(math::fvec3{0.5f, 0.5f, 0.5f});
+	
+	// Apply cascade scale
+	m = math::scale(math::fvec3{0.5f, 0.5f, 1.0f}) * m;
+	
+	for (unsigned int i = 0; i < m_shadow_cascade_count; ++i)
+	{
+		// Apply cascade translation
+		m_shadow_bias_scale_matrices[i] = math::translate(math::fvec3{static_cast<float>(i % 2) * 0.5f, static_cast<float>(i / 2) * 0.5f, 0.0f}) * m;
+	}
+}
+
 } // namespace scene
diff --git a/src/engine/scene/directional-light.hpp b/src/engine/scene/directional-light.hpp
index 56611f0..bf9f59d 100644
--- a/src/engine/scene/directional-light.hpp
+++ b/src/engine/scene/directional-light.hpp
@@ -25,6 +25,7 @@
 #include <engine/math/vector.hpp>
 #include <memory>
 #include <vector>
+#include <span>
 
 namespace scene {
 
@@ -76,25 +77,25 @@ public:
 	}
 	
 	/// Returns a unit vector pointing in the light direction.
-	[[nodiscard]] inline const math::fvec3& get_direction() const noexcept
+	[[nodiscard]] inline constexpr const math::fvec3& get_direction() const noexcept
 	{
 		return m_direction;
 	}
 	
 	/// Returns the color of the light.
-	[[nodiscard]] inline const math::fvec3& get_color() const noexcept
+	[[nodiscard]] inline constexpr const math::fvec3& get_color() const noexcept
 	{
 		return m_color;
 	}
 	
 	/// Returns the illuminance of the light on a surface perpendicular to the light direction.
-	[[nodiscard]] inline float get_illuminance() const noexcept
+	[[nodiscard]] inline constexpr float get_illuminance() const noexcept
 	{
 		return m_illuminance;
 	}
 	
 	/// Returns the color-modulated illuminance of the light on a surface perpendicular to the light direction.
-	[[nodiscard]] inline const math::fvec3& get_colored_illuminance() const noexcept
+	[[nodiscard]] inline constexpr const math::fvec3& get_colored_illuminance() const noexcept
 	{
 		return m_colored_illuminance;
 	}
@@ -184,23 +185,29 @@ public:
 	
 	/// Returns the array of shadow cascade far clipping plane distances.
 	/// @{
-	[[nodiscard]] inline const std::vector<float>& get_shadow_cascade_distances() const noexcept
+	[[nodiscard]] inline constexpr std::span<const float> get_shadow_cascade_distances() const noexcept
 	{
 		return m_shadow_cascade_distances;
 	}
-	[[nodiscard]] inline std::vector<float>& get_shadow_cascade_distances() noexcept
+	[[nodiscard]] inline constexpr std::span<float> get_shadow_cascade_distances() noexcept
 	{
 		return m_shadow_cascade_distances;
 	}
 	/// @}
 	
+	/// Returns the array of shadow cascade bias-scale matrices.
+	[[nodiscard]] inline constexpr std::span<const math::fmat4> get_shadow_bias_scale_matrices() const noexcept
+	{
+		return m_shadow_bias_scale_matrices;
+	}
+	
 	/// Returns the array of world-space to cascade texture-space transformation matrices.
 	/// @{
-	[[nodiscard]] inline const std::vector<math::fmat4>& get_shadow_cascade_matrices() const noexcept
+	[[nodiscard]] inline constexpr std::span<const math::fmat4> get_shadow_cascade_matrices() const noexcept
 	{
 		return m_shadow_cascade_matrices;
 	}
-	[[nodiscard]] inline std::vector<math::fmat4>& get_shadow_cascade_matrices() noexcept
+	[[nodiscard]] inline constexpr std::span<math::fmat4> get_shadow_cascade_matrices() noexcept
 	{
 		return m_shadow_cascade_matrices;
 	}
@@ -212,6 +219,7 @@ private:
 	void transformed() override;
 	void color_updated();
 	void illuminance_updated();
+	void update_shadow_bias_scale_matrices();
 	
 	math::fvec3 m_direction{0.0f, 0.0f, -1.0f};
 	math::fvec3 m_color{1.0f, 1.0f, 1.0f};
@@ -220,12 +228,13 @@ private:
 	
 	bool m_shadow_caster{false};
 	std::shared_ptr<gl::framebuffer> m_shadow_framebuffer{nullptr};
-	float m_shadow_bias{0.005f};
+	float m_shadow_bias{0.001f};
 	unsigned int m_shadow_cascade_count{4};
 	float m_shadow_cascade_coverage{1.0f};
 	float m_shadow_cascade_distribution{0.8f};
-	mutable std::vector<float> m_shadow_cascade_distances;
-	mutable std::vector<math::fmat4> m_shadow_cascade_matrices;
+	std::vector<float> m_shadow_cascade_distances;
+	std::vector<math::fmat4> m_shadow_cascade_matrices;
+	std::vector<math::fmat4> m_shadow_bias_scale_matrices;
 };
 
 } // namespace scene
diff --git a/src/engine/scene/object.hpp b/src/engine/scene/object.hpp
index 6a04027..9c1a8a1 100644
--- a/src/engine/scene/object.hpp
+++ b/src/engine/scene/object.hpp
@@ -42,7 +42,7 @@ public:
 	using aabb_type = geom::box<float>;
 	
 	/// Returns the type ID for this scene object type.
-	virtual const std::size_t get_object_type_id() const noexcept = 0;
+	[[nodiscard]] virtual const std::size_t get_object_type_id() const noexcept = 0;
 	
 	/**
 	 * Adds render operations to a render context.
@@ -55,7 +55,17 @@ public:
 	 *
 	 */
 	void look_at(const vector_type& position, const vector_type& target, const vector_type& up);
-
+	
+	/**
+	 * Sets the layer mask of the object.
+	 *
+	 * @param mask 32-bit layer mask in which each set bit represents a layer in which the object is visible.
+	 */
+	inline constexpr void set_layer_mask(std::uint32_t mask) noexcept
+	{
+		m_layer_mask = mask;
+	}
+	
 	/**
 	 * Sets the transform of the object.
 	 *
@@ -106,27 +116,33 @@ public:
 		transformed();
 	}
 	/// @}
+	
+	/// Returns the layer mask of the object.
+	[[nodiscard]] inline constexpr std::uint32_t get_layer_mask() const noexcept
+	{
+		return m_layer_mask;
+	}
 
 	/// Returns the transform of the object.
-	[[nodiscard]] inline const transform_type& get_transform() const noexcept
+	[[nodiscard]] inline constexpr const transform_type& get_transform() const noexcept
 	{
 		return m_transform;
 	}
 
 	/// Returns the translation of the object.
-	[[nodiscard]] inline const vector_type& get_translation() const noexcept
+	[[nodiscard]] inline constexpr const vector_type& get_translation() const noexcept
 	{
 		return m_transform.translation;
 	}
 
 	/// Returns the rotation of the object.
-	[[nodiscard]] inline const quaternion_type& get_rotation() const noexcept
+	[[nodiscard]] inline constexpr const quaternion_type& get_rotation() const noexcept
 	{
 		return m_transform.rotation;
 	}
 
 	/// Returns the scale of the object.
-	[[nodiscard]] inline const vector_type& get_scale() const noexcept
+	[[nodiscard]] inline constexpr const vector_type& get_scale() const noexcept
 	{
 		return m_transform.scale;
 	}
@@ -136,16 +152,13 @@ public:
 
 protected:
 	static std::size_t next_object_type_id();
-
-private:
-	/// Interpolates between two transforms.
-	static transform_type interpolate_transforms(const transform_type& x, const transform_type& y, float a);
 	
 	/**
 	 * Called every time the scene object's tranform is changed.
 	 */
 	inline virtual void transformed() {}
 	
+	std::uint32_t m_layer_mask{1};
 	transform_type m_transform{transform_type::identity()};
 };
 
@@ -161,7 +174,7 @@ public:
 	/// Unique type ID for this scene object type.
 	static const std::atomic<std::size_t> object_type_id;
 	
-	inline const std::size_t get_object_type_id() const noexcept final
+	[[nodiscard]] inline const std::size_t get_object_type_id() const noexcept final
 	{
 		return object_type_id;
 	}
diff --git a/src/engine/scene/skeletal-mesh.cpp b/src/engine/scene/skeletal-mesh.cpp
index 0afead2..4ea0784 100644
--- a/src/engine/scene/skeletal-mesh.cpp
+++ b/src/engine/scene/skeletal-mesh.cpp
@@ -115,6 +115,7 @@ void skeletal_mesh::render(render::context& ctx) const
 	for (auto& operation: m_operations)
 	{
 		operation.depth = depth;
+		operation.layer_mask = get_layer_mask();
 		ctx.operations.push_back(&operation);
 	}
 }
diff --git a/src/engine/scene/static-mesh.cpp b/src/engine/scene/static-mesh.cpp
index a0860a8..58ba1ef 100644
--- a/src/engine/scene/static-mesh.cpp
+++ b/src/engine/scene/static-mesh.cpp
@@ -113,6 +113,7 @@ void static_mesh::render(render::context& ctx) const
 	for (auto& operation: m_operations)
 	{
 		operation.depth = depth;
+		operation.layer_mask = get_layer_mask();
 		ctx.operations.push_back(&operation);
 	}
 }
diff --git a/src/engine/scene/text.cpp b/src/engine/scene/text.cpp
index c47da97..59809a8 100644
--- a/src/engine/scene/text.cpp
+++ b/src/engine/scene/text.cpp
@@ -79,6 +79,7 @@ void text::render(render::context& ctx) const
 	if (m_vertex_count)
 	{
 		m_render_op.depth = ctx.camera->get_view_frustum().near().distance(get_translation());
+		m_render_op.layer_mask = get_layer_mask();
 		ctx.operations.push_back(&m_render_op);
 	}
 }
diff --git a/src/game/controls/ant-controls.cpp b/src/game/controls/ant-controls.cpp
index c04acfd..b14991d 100644
--- a/src/game/controls/ant-controls.cpp
+++ b/src/game/controls/ant-controls.cpp
@@ -24,6 +24,7 @@
 #include "game/components/legged-locomotion-component.hpp"
 #include "game/components/ovary-component.hpp"
 #include "game/components/spring-arm-component.hpp"
+#include "game/components/scene-component.hpp"
 #include <engine/math/interpolation.hpp>
 #include <engine/math/euler-angles.hpp>
 #include <engine/debug/log.hpp>
@@ -228,7 +229,14 @@ void setup_ant_controls(::game& ctx)
 		(
 			[&](const auto& event)
 			{
-				world::switch_scene(ctx);
+				if (ctx.active_camera_eid == entt::null)
+				{
+					return;
+				}
+				
+				auto& camera_object = *ctx.entity_registry->get<scene_component>(ctx.active_camera_eid).object;
+				
+				camera_object.set_layer_mask(camera_object.get_layer_mask() == 1 ? 2 : 1);
 			}
 		)
 	);
diff --git a/src/game/game.cpp b/src/game/game.cpp
index 7c48329..4cc2228 100644
--- a/src/game/game.cpp
+++ b/src/game/game.cpp
@@ -738,13 +738,13 @@ void game::setup_rendering()
 	{
 		surface_shadow_map_clear_pass = std::make_unique<render::clear_pass>(window->get_rasterizer(), shadow_map_framebuffer.get());
 		surface_shadow_map_clear_pass->set_cleared_buffers(false, true, false);
-		surface_shadow_map_clear_pass->set_clear_depth(1.0f);
+		surface_shadow_map_clear_pass->set_clear_depth(0.0f);
 		
 		surface_shadow_map_pass = std::make_unique<render::shadow_map_pass>(window->get_rasterizer(), resource_manager.get());
 		
 		surface_clear_pass = std::make_unique<render::clear_pass>(window->get_rasterizer(), hdr_framebuffer.get());
 		surface_clear_pass->set_clear_color({0.0f, 0.0f, 0.0f, 1.0f});
-		surface_clear_pass->set_clear_depth(-1.0f);
+		surface_clear_pass->set_clear_depth(0.0f);
 		surface_clear_pass->set_clear_stencil(0);
 		surface_clear_pass->set_cleared_buffers(true, true, true);
 		
@@ -816,7 +816,7 @@ void game::setup_scenes()
 	
 	// Allocate and init surface camera
 	surface_camera = std::make_shared<scene::camera>();
-	surface_camera->set_perspective(math::radians<float>(45.0f), viewport_aspect_ratio, 0.1f, 5000.0f);
+	surface_camera->set_perspective(math::radians<float>(45.0f), viewport_aspect_ratio, 0.1f, 1000.0f);
 	surface_camera->set_compositor(surface_compositor.get());
 	surface_camera->set_composite_index(0);
 	
diff --git a/src/game/graphics.cpp b/src/game/graphics.cpp
index 6147a6b..fb50ecc 100644
--- a/src/game/graphics.cpp
+++ b/src/game/graphics.cpp
@@ -78,7 +78,7 @@ void create_framebuffers(::game& ctx)
 	
 	// Create shadow map framebuffer
 	ctx.shadow_map_depth_texture = std::make_shared<gl::texture_2d>(ctx.shadow_map_resolution, ctx.shadow_map_resolution, gl::pixel_type::float_32, gl::pixel_format::d);
-	ctx.shadow_map_depth_texture->set_wrapping(gl::texture_wrapping::extend, gl::texture_wrapping::extend);
+	ctx.shadow_map_depth_texture->set_wrapping(gl::texture_wrapping::clip, gl::texture_wrapping::clip);
 	ctx.shadow_map_depth_texture->set_filters(gl::texture_min_filter::linear, gl::texture_mag_filter::linear);
 	ctx.shadow_map_depth_texture->set_max_anisotropy(0.0f);
 	ctx.shadow_map_framebuffer = std::make_shared<gl::framebuffer>(ctx.shadow_map_resolution, ctx.shadow_map_resolution);
diff --git a/src/game/states/experiments/treadmill-experiment-state.cpp b/src/game/states/experiments/treadmill-experiment-state.cpp
index 76faec3..7025192 100644
--- a/src/game/states/experiments/treadmill-experiment-state.cpp
+++ b/src/game/states/experiments/treadmill-experiment-state.cpp
@@ -176,42 +176,69 @@ treadmill_experiment_state::treadmill_experiment_state(::game& ctx):
 		// ctx.entity_registry->emplace<scene_component>(nest_exterior_eid, std::move(nest_exterior_scene_component));
 	// }
 	
-	// Create nest interior
-	// {
-		// scene_component nest_interior_scene_component;
-		// nest_interior_scene_component.object = std::make_shared<scene::static_mesh>(ctx.resource_manager->load<render::model>("round-petri-dish-nest-100mm-interior.mdl"));
-		// nest_interior_scene_component.layer_mask = 1;
+	// Create nest exterior
+	{
+		scene_component nest_exterior_scene_component;
+		nest_exterior_scene_component.object = std::make_shared<scene::static_mesh>(ctx.resource_manager->load<render::model>("sphere-nest-100mm-exterior.mdl"));
+		nest_exterior_scene_component.layer_mask = 1;
 		
-		// auto nest_interior_mesh = ctx.resource_manager->load<geom::brep_mesh>("round-petri-dish-nest-100mm-interior.msh");
-		// geom::generate_vertex_normals(*nest_interior_mesh);
+		auto nest_exterior_mesh = ctx.resource_manager->load<geom::brep_mesh>("sphere-nest-100mm-exterior.msh");
 		
-		// auto nest_interior_rigid_body = std::make_unique<physics::rigid_body>();
-		// nest_interior_rigid_body->set_mass(0.0f);
-		// nest_interior_rigid_body->set_collider(std::make_shared<physics::mesh_collider>(std::move(nest_interior_mesh)));
+		auto nest_exterior_rigid_body = std::make_unique<physics::rigid_body>();
+		nest_exterior_rigid_body->set_mass(0.0f);
+		nest_exterior_rigid_body->set_collider(std::make_shared<physics::mesh_collider>(std::move(nest_exterior_mesh)));
 		
-		// auto nest_interior_eid = ctx.entity_registry->create();
-		// ctx.entity_registry->emplace<scene_component>(nest_interior_eid, std::move(nest_interior_scene_component));
-		// ctx.entity_registry->emplace<rigid_body_component>(nest_interior_eid, std::move(nest_interior_rigid_body));
-	// }
+		auto nest_exterior_eid = ctx.entity_registry->create();
+		ctx.entity_registry->emplace<scene_component>(nest_exterior_eid, std::move(nest_exterior_scene_component));
+		ctx.entity_registry->emplace<rigid_body_component>(nest_exterior_eid, std::move(nest_exterior_rigid_body));
+	}
 	
+	// Create nest interior
 	{
 		scene_component nest_interior_scene_component;
-		nest_interior_scene_component.object = std::make_shared<scene::static_mesh>(ctx.resource_manager->load<render::model>("soil-nest.mdl"));
+		nest_interior_scene_component.object = std::make_shared<scene::static_mesh>(ctx.resource_manager->load<render::model>("sphere-nest-100mm-interior.mdl"));
+		nest_interior_scene_component.object->set_layer_mask(0b10);
 		nest_interior_scene_component.layer_mask = 1;
 		
-		auto nest_interior_mesh = ctx.resource_manager->load<geom::brep_mesh>("soil-nest.msh");
+		auto nest_interior_mesh = ctx.resource_manager->load<geom::brep_mesh>("sphere-nest-100mm-interior.msh");
 		
 		auto nest_interior_rigid_body = std::make_unique<physics::rigid_body>();
 		nest_interior_rigid_body->set_mass(0.0f);
 		nest_interior_rigid_body->set_collider(std::make_shared<physics::mesh_collider>(std::move(nest_interior_mesh)));
+		nest_interior_rigid_body->get_collider()->set_layer_mask(0b10);
 		
 		auto nest_interior_eid = ctx.entity_registry->create();
 		ctx.entity_registry->emplace<scene_component>(nest_interior_eid, std::move(nest_interior_scene_component));
 		ctx.entity_registry->emplace<rigid_body_component>(nest_interior_eid, std::move(nest_interior_rigid_body));
 	}
 	
+	
+	// Create rectangle light
+	{
+		area_light = std::make_unique<scene::rectangle_light>();
+		area_light->set_luminous_flux(5000000.0f);
+		area_light->set_translation({0.0f, 0.0f, 0.0f});
+		area_light->set_rotation(math::fquat::rotate_x(math::radians(90.0f)));
+		area_light->set_scale(5.0f);
+		area_light->set_layer_mask(0b10);
+		ctx.surface_scene->add_object(*area_light);
+		
+		// Create light rectangle
+		auto light_rectangle_model = ctx.resource_manager->load<render::model>("light-rectangle.mdl");
+		auto light_rectangle_material = std::make_shared<render::material>(*light_rectangle_model->get_groups().front().material);
+		light_rectangle_emissive = std::static_pointer_cast<render::matvar_fvec3>(light_rectangle_material->get_variable("emissive"));
+		light_rectangle_emissive->set(area_light->get_colored_luminance());
+		auto light_rectangle_static_mesh = std::make_shared<scene::static_mesh>(light_rectangle_model);
+		light_rectangle_static_mesh->set_material(0, light_rectangle_material);
+		light_rectangle_static_mesh->set_transform(area_light->get_transform());
+		light_rectangle_static_mesh->set_layer_mask(area_light->get_layer_mask());
+		auto light_rectangle_eid = ctx.entity_registry->create();
+		ctx.entity_registry->emplace<scene_component>(light_rectangle_eid, std::move(light_rectangle_static_mesh), std::uint8_t{1});
+	}
+	
 	// Create worker
 	auto worker_skeletal_mesh = std::make_unique<scene::skeletal_mesh>(worker_model);
+	worker_skeletal_mesh->set_layer_mask(0b11);
 	
 	// Create worker IK rig
 	const auto& worker_skeleton = worker_model->get_skeleton();
@@ -310,7 +337,7 @@ treadmill_experiment_state::treadmill_experiment_state(::game& ctx):
 	::world::set_time(ctx, 2022, 6, 21, 12, 0, 0.0);
 	
 	// Init time scale
-	double time_scale = 60.0;
+	double time_scale = 0.0;
 	
 	// Set time scale
 	::world::set_time_scale(ctx, time_scale);
@@ -385,6 +412,7 @@ void treadmill_experiment_state::create_third_person_camera_rig()
 	spring_arm.far_focal_plane_height = 80.0 * subject_scale;
 	spring_arm.near_hfov = math::radians(90.0);
 	spring_arm.far_hfov = math::radians(45.0);
+	// spring_arm.far_hfov = math::radians(90.0);
 	spring_arm.zoom = 0.25;
 	spring_arm.focal_point_offset = {0, static_cast<double>(worker_phenome->legs->standing_height) * subject_scale, 0};
 	
@@ -535,7 +563,9 @@ void treadmill_experiment_state::setup_controls()
 				const auto& mouse_position = (*ctx.input_manager->get_mice().begin())->get_position();
 				const auto mouse_ray = get_mouse_ray(mouse_position);
 				
-				if (auto trace = ctx.physics_system->trace(mouse_ray))
+				const auto& camera_object = *ctx.entity_registry->get<::scene_component>(ctx.active_camera_eid).object;
+				
+				if (auto trace = ctx.physics_system->trace(mouse_ray, entt::null, camera_object.get_layer_mask()))
 				{
 					// debug::log::debug("HIT! EID: {}; distance: {}; face: {}", static_cast<int>(std::get<0>(*trace)), std::get<1>(*trace), std::get<2>(*trace));
 					
diff --git a/src/game/states/experiments/treadmill-experiment-state.hpp b/src/game/states/experiments/treadmill-experiment-state.hpp
index 043526c..815895f 100644
--- a/src/game/states/experiments/treadmill-experiment-state.hpp
+++ b/src/game/states/experiments/treadmill-experiment-state.hpp
@@ -30,6 +30,7 @@
 #include <engine/geom/primitives/plane.hpp>
 #include <engine/math/angles.hpp>
 #include <engine/scene/light-probe.hpp>
+#include <engine/scene/rectangle-light.hpp>
 #include <engine/geom/bvh/bvh.hpp>
 #include <engine/geom/brep/brep-mesh.hpp>
 #include <engine/animation/ik/ik-rig.hpp>
@@ -119,6 +120,7 @@ private:
 	std::shared_ptr<ik_rig> worker_ik_rig;
 	
 	std::shared_ptr<scene::light_probe> sky_probe;
+	std::shared_ptr<scene::rectangle_light> area_light;
 };
 
 #endif // ANTKEEPER_TREADMILL_EXPERIMENT_STATE_HPP
diff --git a/src/game/systems/render-system.cpp b/src/game/systems/render-system.cpp
index 8422e51..ff287c3 100644
--- a/src/game/systems/render-system.cpp
+++ b/src/game/systems/render-system.cpp
@@ -72,7 +72,7 @@ void render_system::draw(float alpha)
 {
 	if (renderer)
 	{
-		for (const scene::collection* collection: layers)
+		for (scene::collection* collection: layers)
 		{
 			renderer->render(t + dt * alpha, dt, alpha, *collection);
 		}
diff --git a/src/game/world.cpp b/src/game/world.cpp
index 1a6ba54..21b0265 100644
--- a/src/game/world.cpp
+++ b/src/game/world.cpp
@@ -363,9 +363,9 @@ void create_sun(::game& ctx)
 		ctx.sun_light = std::make_unique<scene::directional_light>();
 		ctx.sun_light->set_shadow_caster(true);
 		ctx.sun_light->set_shadow_framebuffer(ctx.shadow_map_framebuffer);
-		ctx.sun_light->set_shadow_bias(0.005f);
+		ctx.sun_light->set_shadow_bias(0.001f);
 		ctx.sun_light->set_shadow_cascade_count(4);
-		ctx.sun_light->set_shadow_cascade_coverage(0.15f);
+		ctx.sun_light->set_shadow_cascade_coverage(0.05f);
 		ctx.sun_light->set_shadow_cascade_distribution(0.8f);
 		
 		// Add sun light scene objects to surface scene