Merge branch 'fb-ibm-coupling' into dev

9 files changed, 787 insertions, 24 deletions

diff --git a/default.nix b/default.nix
index d233d90..c8e99f5 100644
--- a/default.nix
+++ b/default.nix
@@ -161,11 +161,23 @@ in rec {
 			inherit pname version stdenv forstio adaptive-cpp;
 			inherit kel;
 		};
+		
+		settling_cubes_2d_hlbm_gpu = pkgs.callPackage ./examples/settling_spheres_2d_hlbm_gpu/.nix/derivation.nix {
+			inherit pname version stdenv forstio adaptive-cpp;
+			inherit kel;
+		};
 
 		heterogeneous_computing = pkgs.callPackage ./examples/heterogeneous_computing/.nix/derivation.nix {
 			inherit pname version stdenv forstio adaptive-cpp;
 			inherit kel;
 		};
+
+		settling_particles = pkgs.symlinkJoin {
+			name = "kel-lbm-settling_particles-${version}";
+			paths = [
+				examples.settling_cubes_2d_ibm_gpu
+			];
+		};
 	};
 
 	debug = {
@@ -190,6 +202,8 @@ in rec {
 				examples.poiseulle_particles_2d_ibm_gpu
 			];
 		};
+
+
 	};
 
 	default = release.examples;
diff --git a/examples/settling_spheres_2d_hlbm_gpu/.nix/derivation.nix b/examples/settling_spheres_2d_hlbm_gpu/.nix/derivation.nix
new file mode 100644
index 0000000..26b41f2
--- /dev/null
+++ b/examples/settling_spheres_2d_hlbm_gpu/.nix/derivation.nix
@@ -0,0 +1,41 @@
+{ lib
+, stdenv
+, scons
+, clang-tools
+, forstio
+, python3
+, pname
+, version
+, adaptive-cpp
+, kel
+}:
+
+stdenv.mkDerivation {
+	pname = pname + "-examples-" + "setting_spheres_2d_hlbm_gpu";
+	inherit version;
+	src = ./..;
+
+	nativeBuildInputs = [
+		scons
+		clang-tools
+		python3
+	];
+
+	buildInputs = [
+		forstio.core
+		forstio.async
+		forstio.codec
+		forstio.codec-unit
+		forstio.io
+    forstio.remote
+    forstio.remote-filesystem
+		forstio.codec-json
+		adaptive-cpp
+		kel.lbm.core
+		kel.lbm.sycl
+	];
+
+	preferLocalBuild = true;
+
+	outputs = [ "out" "dev" ];
+}
diff --git a/examples/settling_spheres_2d_hlbm_gpu/SConscript b/examples/settling_spheres_2d_hlbm_gpu/SConscript
new file mode 100644
index 0000000..ae08056
--- /dev/null
+++ b/examples/settling_spheres_2d_hlbm_gpu/SConscript
@@ -0,0 +1,34 @@
+#!/bin/false
+
+import os
+import os.path
+import glob
+
+
+Import('env')
+
+dir_path = Dir('.').abspath
+
+# Environment for base library
+examples_env = env.Clone();
+examples_env['CXX'] = 'syclcc-clang';
+examples_env['CXXFLAGS'] += ['-O3'];
+
+examples_env.sources = sorted(glob.glob(dir_path + "/*.cpp"))
+examples_env.headers = sorted(glob.glob(dir_path + "/*.hpp"))
+
+env.sources += examples_env.sources;
+env.headers += examples_env.headers;
+
+# Cavity2D
+examples_objects = [];
+examples_env.add_source_files(examples_objects, ['sim.cpp'], shared=False);
+examples_env.poiseulle_2d_gpu = examples_env.Program('#bin/settling_cubes_2d_ibm_gpu', [examples_objects]);
+
+# Set Alias
+env.examples = [
+	examples_env.poiseulle_2d_gpu
+];
+env.Alias('examples', env.examples);
+env.targets += ['examples'];
+env.Install('$prefix/bin/', env.examples);
diff --git a/examples/settling_spheres_2d_hlbm_gpu/SConstruct b/examples/settling_spheres_2d_hlbm_gpu/SConstruct
new file mode 100644
index 0000000..0611b67
--- /dev/null
+++ b/examples/settling_spheres_2d_hlbm_gpu/SConstruct
@@ -0,0 +1,81 @@
+#!/usr/bin/env python3
+
+import sys
+import os
+import os.path
+import glob
+import re
+
+
+if sys.version_info < (3,):
+    def isbasestring(s):
+        return isinstance(s,basestring)
+else:
+    def isbasestring(s):
+        return isinstance(s, (str,bytes))
+
+def add_kel_source_files(self, sources, filetype, lib_env=None, shared=False, target_post=""):
+
+    if isbasestring(filetype):
+        dir_path = self.Dir('.').abspath
+        filetype = sorted(glob.glob(dir_path+"/"+filetype))
+
+    for path in filetype:
+        target_name = re.sub( r'(.*?)(\.cpp|\.c\+\+)', r'\1' + target_post, path )
+        if shared:
+            target_name+='.os'
+            sources.append( self.SharedObject( target=target_name, source=path ) )
+        else:
+            target_name+='.o'
+            sources.append( self.StaticObject( target=target_name, source=path ) )
+    pass
+
+def isAbsolutePath(key, dirname, env):
+	assert os.path.isabs(dirname), "%r must have absolute path syntax" % (key,)
+
+env_vars = Variables(
+	args=ARGUMENTS
+)
+
+env_vars.Add('prefix',
+	help='Installation target location of build results and headers',
+	default='/usr/local/',
+	validator=isAbsolutePath
+)
+
+env_vars.Add('build_examples',
+	help='If examples should be built',
+	default="true"
+)
+
+env=Environment(ENV=os.environ, variables=env_vars, CPPPATH=[],
+    CPPDEFINES=['SAW_UNIX'],
+    CXXFLAGS=[
+        '-std=c++20',
+        '-g',
+        '-Wall',
+        '-Wextra'
+    ],
+    LIBS=[
+        'forstio-core',
+        'forstio-async',
+        'forstio-io'
+    ]
+);
+env.__class__.add_source_files = add_kel_source_files
+env.Tool('compilation_db');
+env.cdb = env.CompilationDatabase('compile_commands.json');
+
+env.objects = [];
+env.sources = [];
+env.headers = [];
+env.targets = [];
+
+Export('env')
+SConscript('SConscript')
+
+env.Alias('cdb', env.cdb);
+env.Alias('all', [env.targets]);
+env.Default('all');
+
+env.Alias('install', '$prefix')
diff --git a/examples/settling_spheres_2d_hlbm_gpu/sim.cpp b/examples/settling_spheres_2d_hlbm_gpu/sim.cpp
new file mode 100644
index 0000000..eb3f377
--- /dev/null
+++ b/examples/settling_spheres_2d_hlbm_gpu/sim.cpp
@@ -0,0 +1,469 @@
+#include <kel/lbm/sycl/lbm.hpp>
+#include <kel/lbm/lbm.hpp>
+#include <kel/lbm/particle.hpp>
+
+#include <forstio/io/io.hpp>
+#include <forstio/remote/filesystem/easy.hpp>
+#include <forstio/codec/json/json.hpp>
+#include <forstio/codec/simple.hpp>
+#include <forstio/codec/math.hpp>
+
+namespace kel {
+namespace lbm {
+
+constexpr uint64_t dim_x = 512ul;
+constexpr uint64_t dim_y = dim_x * 2ul;
+
+constexpr uint64_t particle_amount = 16ul;
+
+namespace sch {
+using namespace saw::schema;
+
+using InfoChunk = Chunk<UInt8, 0u, dim_x, dim_y>;
+
+template<typename T, typename Desc>
+using DfChunk = Chunk<FixedArray<T,Desc::Q>, 1u, dim_x, dim_y>;
+
+template<typename T, typename Desc>
+using ScalarChunk = Chunk<Scalar<T>, 0u, dim_x, dim_y>;
+
+template<typename T, typename Desc>
+using VectorChunk = Chunk<Vector<T,Desc::D>, 0u, dim_x, dim_y>;
+
+template<typename T, typename Desc>
+using ChunkStruct = Struct<
+	Member<InfoChunk, "info">,
+	Member<DfChunk<T,Desc>, "dfs">,
+	Member<DfChunk<T,Desc>, "dfs_old">,
+	Member<VectorChunk<T,Desc>, "p_N">,
+	Member<ScalarChunk<T,Desc>, "p_D">
+>;
+
+template<typename T, typename Desc>
+using VelChunk = Chunk<Vector<T,Desc::D>, 0u, dim_x, dim_y>;
+
+template<typename T>
+using RhoChunk = Chunk<Scalar<T>, 0u, dim_x, dim_y>;
+
+template<typename T>
+using PorChunk = Chunk<Scalar<T>, 0u, dim_x, dim_y>;
+
+template<typename T, typename Desc>
+using MacroStruct = Struct<
+	Member<VelChunk<T,Desc>, "velocity">,
+	Member<RhoChunk<T>, "density">,
+	Member<PorChunk<T>, "porosity">
+>;
+
+template<typename T, typename Desc>
+using ParticleSpheroidGroup = ParticleGroup<
+	T,
+	Desc::D,
+	sch::ParticleCollisionSpheroid<T,2.0f>
+>;
+
+template<typename T, typename Desc>
+using ParticleGroups = Tuple<
+	ParticleSpheroidGroup<T,Desc>
+>;
+
+
+}
+
+template<typename T, typename Desc>
+saw::error_or<void> setup_initial_conditions(
+		saw::data<sch::ChunkStruct<T,Desc>>& fields,
+		saw::data<sch::MacroStruct<T,Desc>>& macros,
+		saw::data<sch::ParticleSpheroidGroup<T,Desc>>& particles
+){
+	auto& info_f = fields.template get<"info">();
+	// Set everything as walls
+	iterator<Desc::D>::apply(
+		[&](auto& index){
+			info_f.at(index).set(1u);
+		},
+		{},
+		info_f.get_dims(),
+		{}
+	);
+	// Fluid
+	iterator<Desc::D>::apply(
+		[&](auto& index){
+			info_f.at(index).set(2u);
+		},
+		{},
+		info_f.get_dims(),
+		{{1u,1u}}
+	);
+	//
+	auto& df_f = fields.template gStarted hearing about similar cases not long after, many of which were successful on the part of the crooks. Scary stuff. et<"dfs_old">();
+	auto& rho_f = macros.template get<"density">();
+	auto& vel_f = macros.template get<"velocity">();
+	
+	iterator<Desc::D>::apply(
+		[&](auto& index){
+			auto& df = df_f.at(index);
+			auto& rho = rho_f.at(index);
+			rho.at({}) = {1};
+			auto& vel = vel_f.at(index);
+			auto eq = equilibrium<T,Desc>(rho,vel);
+
+			df = eq;
+		},
+		{},// 0-index
+		df_f.get_dims()
+	);
+
+	// Particles
+	{
+		saw::data<sch::Scalar<T>> dense_p;
+		dense_p.at({}).set(1);
+		// auto& spheroid_group = particles.template get<0u>();
+		auto& spheroid_group = particles;
+
+		spheroid_group = create_spheroid_particle_group<T,Desc::D,2.0f>(
+			dense_p,
+			{64u}
+		);
+
+		{
+			auto& p = spheroid_group.template get<"particles">();
+
+			/// 16 if I remember correctly?
+			p = {{{particle_amount}}};
+
+			iterator<1u>::apply(
+				[&](auto& index){
+					// Set Pos here?
+					auto& p_ind = p.at(index);
+
+					auto& p_rb = p_ind.template get<"rigid_body">();
+					auto& p_pos = p_rb.template get<"position">();
+
+					saw::data<sch::Vector<T,Desc::D>> p;
+					uint64_t x = index.at({0u}).get() % 8u;
+					uint64_t y = index.at({1u}).get() / 8u;
+					p.at({{0u}}).set( 0.2 + 0.6 / (x-1u) );
+					p.at({{1u}}).set( 0.8 + y * 0.1 );
+
+					p_pos = p;
+
+					auto& p_pos_old = p_rb.template get<"position_old">();
+					p_pos_old = p_pos;
+				},
+				{},
+				p.meta()
+			);
+		}
+	}
+	// Particle in hacky flavour
+	{}
+
+	return saw::make_void();
+}
+
+template<typename T, typename Desc>
+saw::error_or<void> step(
+	saw::data<sch::Ptr<sch::ChunkStruct<T,Desc>>,encode::Sycl<saw::encode::Native>>& fields,
+	saw::data<sch::Ptr<sch::MacroStruct<T,Desc>>,encode::Sycl<saw::encode::Native>>& macros,
+	saw::data<sch::Ptr<sch::ParticleSpheroidGroup<T,Desc>>,encode::Sycl<saw::encode::Native>>& p_group,
+	saw::data<sch::UInt64> t_i,
+	device& dev
+){
+	auto& q = dev.get_handle();
+	auto& info_f = fields.template get<"info">();
+
+	auto& parts = p_group.template get<"particles">();
+	auto& p_mask = p_group.template get<"mask">();
+	auto& vels = macros.template get<"velocity">();
+	auto& forces = macros.template get<"force">();
+
+	auto p_meta = parts.meta();
+	q.submit([&](acpp::sycl::handler& h){
+
+		h.parallel_for(acpp::sycl::range<Desc::D>{dim_x,dim_y}, [=](acpp::sycl::id<Desc::D> idx){
+			saw::data<sch::FixedArray<sch::UInt64,Desc::D>> index;
+			for(uint64_t i = 0u; i < Desc::D; ++i){
+				index.at({{i}}).set(idx[i]);
+			}
+
+			// Reset the force to zero
+			forces.at(index) = {};
+		});
+	}).wait();
+
+	q.submit([&](acpp::sycl::handler& h){
+		h.parallel_for(acpp::sycl::range<1u>{p_meta.at({0u}).get()}, [=](acpp::sycl::id<1u> idx){
+
+			saw::data<sch::FixedArray<sch::UInt64,1u>> index;
+			for(uint64_t i = 0u; i < 1u; ++i){
+				index.at({{i}}).set(idx[i]);
+			}
+
+			auto& pi = parts.at(index);
+			auto& pirb = pi.template get<"rigid_body">();
+
+			auto& p_pos = pirb.template get<"position">();
+			auto& p_rot = pirb.template get<"rotation">();
+			auto& p_acc = pirb.template get<"acceleration">();
+
+			
+
+			saw::data<sch::Scalar<T>> delta_t;
+			delta_t.at({}).set(1.0f);
+			verlet_step_lambda<T,Desc::D>(p,delta_t);
+		});
+	}).wait();
+
+	// auto coll_ev = 
+	q.submit([&](acpp::sycl::handler& h){
+		// Need nicer things to handle the flow. I see improvement here
+		component<T,Desc,cmpt::BGK, encode::Sycl<saw::encode::Native>> collision{0.8};
+		component<T,Desc,cmpt::BounceBack,encode::Sycl<saw::encode::Native>> bb;
+
+		h.parallel_for(acpp::sycl::range<Desc::D>{dim_x,dim_y}, [=](acpp::sycl::id<Desc::D> idx){
+			saw::data<sch::FixedArray<sch::UInt64,Desc::D>> index;
+			for(uint64_t i = 0u; i < Desc::D; ++i){
+				index.at({{i}}).set(idx[i]);
+			}
+
+			auto info = info_f.at(index);
+			
+			switch(info.get()){
+				case 0u:
+				break;
+				case 1u:
+					bb.apply(fields,index,t_i);
+				break;
+				case 2u:
+					// collision.apply(fields,macros,index,t_i);
+					break;
+				default:
+				break;
+			}
+		});
+	}).wait();
+
+	// Step
+	/*
+	q.submit([&](acpp::sycl::handler& h){
+		// h.depends_on(collision_ev);
+	}).wait();
+	*/
+
+	return saw::make_void();
+}
+}
+}
+
+template<typename T, typename Desc>
+saw::error_or<void> lbm_main(int argc, char** argv){
+	using namespace kel::lbm;
+
+	using dfi = df_info<T,Desc>;
+
+	auto eo_lbm_env = lbm_directory();
+	if(eo_lbm_env.is_error()){
+		return std::move(eo_lbm_env.get_error());
+	}
+	auto& lbm_env = eo_lbm_env.get_value();
+
+	auto out_dir = lbm_env.data_dir / "settling_cubes_2d_ibm_gpu";
+
+	{
+		std::error_code ec;
+		std::filesystem::create_directories(out_dir,ec);
+		if(ec != std::errc{}){
+			return saw::make_error<saw::err::critical>("Could not create output directory");
+		}
+	}
+
+	converter<T> conv {
+		// delta_x
+		{{1.0}},
+		// delta_t
+		{{1.0}}
+	};
+	
+	print_lbm_meta<T,Desc>(conv,{0.05},{0.01},{0.4 * dim_y});
+
+	// saw::data<sch::FixedArray<sch::UInt64,Desc::D>> meta{{dim_x,dim_y}};
+	auto lbm_data_ptr = saw::heap<saw::data<sch::ChunkStruct<T,Desc>>>();
+	auto lbm_macro_data_ptr = saw::heap<saw::data<sch::MacroStruct<T,Desc>>>();
+	auto lbm_particle_data_ptr = saw::heap<saw::data<sch::ParticleSpheroidGroup<T,Desc>>>();
+	// auto lbm_particles_ptr = saw::heap<saw::data<sch::FixedArray<sch::ParticleRigidBody<T,Desc::D>,part_count>>>();
+	// saw::data<sch::Array<T,Desc::D>> p_mask;
+
+	std::cout<<"Estimated Bytes of LBM Fields: "<<memory_estimate<sch::ChunkStruct<T,Desc>,sch::MacroStruct<T,Desc>>().get()<<std::endl;
+
+	auto eo_aio = saw::setup_async_io();
+	if(eo_aio.is_error()){
+		return std::move(eo_aio.get_error());
+	}
+	auto& aio = eo_aio.get_value();
+	saw::wait_scope wait{aio.event_loop};
+
+	bool krun = true;
+	bool print_status = false;
+	aio.event_port.on_signal(saw::Signal::Terminate).then([&](){
+		krun = false;
+	}).detach();
+	aio.event_port.on_signal(saw::Signal::User1).then([&](){
+		print_status = true;
+	}).detach();
+
+	device dev;
+
+	auto& sycl_q = dev.get_handle();
+
+	sycl_q.wait();
+	{
+		auto eov = setup_initial_conditions<T,Desc>(*lbm_data_ptr,*lbm_macro_data_ptr,*lbm_particle_data_ptr);
+		if(eov.is_error()){
+			return eov;
+		}
+	}
+	{
+		auto eov = write_vtk_file(out_dir,"initial_state",0u,*lbm_data_ptr);
+		if(eov.is_error()){
+			return eov;
+		}
+	}
+
+	saw::data<sch::ChunkStruct<T,Desc>, encode::Sycl<saw::encode::Native>> lbm_sycl_data{sycl_q};
+	saw::data<sch::MacroStruct<T,Desc>, encode::Sycl<saw::encode::Native>> lbm_sycl_macro_data{sycl_q};
+	saw::data<sch::ParticleSpheroidGroup<T,Desc>, encode::Sycl<saw::encode::Native>> lbm_sycl_particle_data{sycl_q};
+
+	{
+		auto eov = dev.copy_to_device(*lbm_data_ptr,lbm_sycl_data);
+		if(eov.is_error()){
+			return eov;
+		}
+	}
+	{
+		auto eov = dev.copy_to_device(*lbm_macro_data_ptr,lbm_sycl_macro_data);
+		if(eov.is_error()){
+			return eov;
+		}
+	}
+	{
+		auto eov = dev.copy_to_device(*lbm_particle_data_ptr,lbm_sycl_particle_data);
+		if(eov.is_error()){
+			return eov;
+		}
+	}
+	sycl_q.wait();
+
+	auto lsd_view = make_view(lbm_sycl_data);
+	auto lsdm_view = make_view(lbm_sycl_macro_data);
+	auto lsdp_view = make_view(lbm_sycl_particle_data);
+
+	{
+		auto eov = write_vtk_file(out_dir,"ms",0u, *lbm_macro_data_ptr);
+		if(eov.is_error()){
+			return eov;
+		}
+	}
+	saw::data<sch::UInt64> time_steps{16u*4096ul};
+
+	auto& info_f = lsd_view.template get<"info">();
+
+	for(saw::data<sch::UInt64> i{0u}; i < time_steps and krun; ++i){
+		// BC + Collision
+		{
+			auto eov = step<T,Desc>(lsd_view,lsdm_view,lsdp_view,i,dev);
+			if(eov.is_error()){
+				return eov;
+			}
+		}
+		sycl_q.wait();
+		if(i.get()%1u ==0u){
+			{
+				auto eov = dev.copy_to_host(lbm_sycl_macro_data,*lbm_macro_data_ptr);
+				if(eov.is_error()){
+					return eov;
+				}
+			}
+			{
+				auto eov = write_vtk_file(out_dir,"m",i.get(), *lbm_macro_data_ptr);
+				if(eov.is_error()){
+					return eov;
+				}
+			}
+		}
+		/*
+		{
+			{
+				auto eov = dev.copy_to_host(lbm_sycl_data,*lbm_data_ptr);
+				if(eov.is_error()){
+					return eov;
+				}
+			}
+			{
+				auto eov = write_csv_file(out_dir,"lbm",i.get(), *lbm_data_ptr);
+				if(eov.is_error()){
+					return eov;
+				}
+			}
+		}
+		*/
+		// Stream
+		sycl_q.submit([&](acpp::sycl::handler& h){
+			component<T,Desc,cmpt::Stream,encode::Sycl<saw::encode::Native>> stream;
+
+			h.parallel_for(acpp::sycl::range<Desc::D>{dim_x,dim_y}, [=](acpp::sycl::id<Desc::D> idx){
+				saw::data<sch::FixedArray<sch::UInt64,Desc::D>> index;
+				for(uint64_t i = 0u; i < Desc::D; ++i){
+					index.at({{i}}).set(idx[i]);
+				}
+				
+				auto info = info_f.at(index);
+				
+				if(info.get() > 0u){
+					stream.apply(lsd_view,index,i);
+				}
+			});
+		}).wait();
+		wait.poll();
+		if(print_status){
+			std::cout<<"Status: "<<i.get()<<" of "<<time_steps.get()<<" - "<<(i.template cast_to<sch::Float64>().get() * 100 / time_steps.get())<<"%"<<std::endl;
+			print_status = false;
+		}
+		print_progress_bar(i.get(), time_steps.get()-1u);
+	}
+
+	// After Loop
+	sycl_q.wait();
+	{
+		auto eov = dev.copy_to_host(lbm_sycl_macro_data,*lbm_macro_data_ptr);
+		if(eov.is_error()){
+			return eov;
+		}
+	}
+	{
+		auto eov = write_vtk_file(out_dir,"m",time_steps.get(), *lbm_macro_data_ptr);
+		if(eov.is_error()){
+			return eov;
+		}
+	}
+
+	sycl_q.wait();
+	return saw::make_void();
+}
+
+using FloatT = kel::lbm::sch::Float32;
+
+int main(int argc, char** argv){
+	auto eov = lbm_main<FloatT,kel::lbm::sch::D2Q9>(argc, argv);
+	if(eov.is_error()){
+		auto& err = eov.get_error();
+		std::cerr<<"[Error] "<<err.get_category();
+		auto err_msg = err.get_message();
+		if(err_msg.size() > 0u){
+			std::cerr<<" - "<<err_msg;
+		}
+		std::cerr<<std::endl;
+		return err.get_id();
+	}
+	return 0;
+}
diff --git a/lib/core/c++/chunk.hpp b/lib/core/c++/chunk.hpp
index 0f92437..635af91 100644
--- a/lib/core/c++/chunk.hpp
+++ b/lib/core/c++/chunk.hpp
@@ -77,6 +77,11 @@ public:
 		return values_.at(ind);
 	}
 
+	/*
+	const data<ValueSchema, Encode>& neighbour_at(const data<schema::FixedArray<schema::UInt64,sizeof...(Sides)>>& index) const {
+	}
+	*/
+
 	static constexpr auto get_dims(){
 		return data<schema::FixedArray<schema::UInt64, sizeof...(Sides)>,Encode>{{Sides...}};
 	}
diff --git a/lib/core/c++/hlbm.hpp b/lib/core/c++/hlbm.hpp
index 7590cc2..6ae7d80 100644
--- a/lib/core/c++/hlbm.hpp
+++ b/lib/core/c++/hlbm.hpp
@@ -43,8 +43,8 @@ public:
 /**
  * HLBM collision operator for LBM
  */
-template<typename T, typename Descriptor, typename Encode>
-class component<T, Descriptor, cmpt::Hlbm, Encode> final {
+template<typename T, typename Desc, typename Encode>
+class component<T, Desc, cmpt::Hlbm, Encode> final {
 private:
 	typename saw::native_data_type<T>::type relaxation_;
 	saw::data<T> frequency_;
@@ -55,7 +55,7 @@ public:
 	{}
 
 	template<typename CellFieldSchema, typename MacroFieldSchema>
-	void apply(const saw::data<CellFieldSchema, Encode>& field, const saw::data<MacroFieldSchema,Encode>& macros, saw::data<sch::FixedArray<sch::UInt64,Descriptor::D>> index, saw::data<sch::UInt64> time_step) const {
+	void apply(const saw::data<CellFieldSchema, Encode>& field, const saw::data<MacroFieldSchema,Encode>& macros, saw::data<sch::FixedArray<sch::UInt64,Desc::D>> index, saw::data<sch::UInt64> time_step) const {
 		
 		bool is_even = ((time_step.get() % 2) == 0);
 
@@ -68,9 +68,9 @@ public:
 		auto& vel_f = macros.template get<"velocity">();
 
 		saw::data<sch::Scalar<T>>& rho = rho_f.at(index);
-		saw::data<sch::Vector<T,Descriptor::D>>& vel = vel_f.at(index);
+		saw::data<sch::Vector<T,Desc::D>>& vel = vel_f.at(index);
 
-		compute_rho_u<T,Descriptor>(dfs_old_f.at(index), rho, vel);
+		compute_rho_u<T,Desc>(dfs_old_f.at(index), rho, vel);
 
 		auto& porosity = porosity_f.at(index);
 		saw::data<sch::Scalar<T>> one;
@@ -80,13 +80,13 @@ public:
 		auto& N = particle_N_f.at(index);
 		auto& D = particle_D_f.at(index);
 		// Convex combination of velocities
-		vel = vel * porosity + [&]() -> saw::data<sch::Vector<T,Descriptor::D>> {
+		vel = vel * porosity + [&]() -> saw::data<sch::Vector<T,Desc::D>> {
 			return (D.at({}).get() > 0.0 ? N * flip_porosity / D : N);
 		}();
 		// Equilibrium
-		auto eq = equilibrium<T,Descriptor>(rho,vel);
+		auto eq = equilibrium<T,Desc>(rho,vel);
 
-		for(uint64_t i = 0u; i < Descriptor::Q; ++i){
+		for(uint64_t i = 0u; i < Desc::Q; ++i){
 			dfs_old_f.at(index).at({i}) = dfs_old_f.at(index).at({i}) + frequency_ * (eq.at(i) - dfs_old_f.at(index).at({i}));
 		}
 
@@ -96,20 +96,55 @@ public:
 	}
 };
 
-template<typename T, typename Descriptor, typename Encode>
-class component<T, Descriptor, cmpt::HlbmParticle, Encode> final {
+namespace impl {
+
+}
+
+template<typename T, typename Desc, typename Encode>
+class component<T, Desc, cmpt::HlbmParticle, Encode> final {
 private:
-	typename saw::native_data_type<T>::type relaxation_;
-	saw::data<T> frequency_;
+	template<typename CellFieldSchema, typename MacroFieldSchema, typename ParticleSchema, uint64_t i>
+	void apply_i(const saw::data<CellFieldSchema, Encode>& field, const saw::data<MacroFieldSchema,Encode>& macros, const saw::data<ParticleSchema,Encode>& part_groups, saw::data<sch::FixedArray<sch::UInt64,1u>> index, saw::data<sch::UInt64> time_step) const {
+		
+	}	
 public:
+	/*
+	template<typename CellFieldSchema, typename MacroFieldSchema, typename ParticleSchema, uint64_t i>
+	void apply_i()
+	*/
 
 	template<typename CellFieldSchema, typename MacroFieldSchema, typename ParticleSchema>
-	void apply(const saw::data<CellFieldSchema, Encode>& field, const saw::data<MacroFieldSchema,Encode>& macros, const saw::data<ParticleSchema,Encode>& particles, saw::data<sch::FixedArray<sch::UInt64,1u>> index, saw::data<sch::UInt64> time_step) const {
+	void apply(const saw::data<CellFieldSchema, Encode>& field, const saw::data<MacroFieldSchema,Encode>& macros, const saw::data<ParticleSchema,Encode>& part_groups, saw::data<sch::FixedArray<sch::UInt64,1u>> index, saw::data<sch::UInt64> time_step) const {
 		/// Figure out how to access the particle list
 		// auto& p = particles.at(i);
 
 		/// Iterate over the grid bounds
 		// auto& grid = p.template get<"grid">();
+
+		auto& part_spheroid_group = part_groups.template get<0>();
+		{
+			auto& parts = part_spheroid_group.template get<"particles">();
+			auto parts_size = parts.size();
+
+			auto& pi = parts.at(index);
+			auto& pirb = pi.template get<"rigid_body">();
+			auto& pirb_pos = pirb.template get<"position">();
+
+			saw::data<sch::FixedArray<sch::UInt64,Desc::D>> start;
+			saw::data<sch::FixedArray<sch::UInt64,Desc::D>> stop;
+
+			/// Ok, I iterate over the space which covers our particle? So lower bounds to upper bounds
+			for(uint64_t i{0u}; i < Desc::D; ++i){
+				
+			}
+
+			iterator<Desc::D>::apply([&](const auto& index){
+				// ask for the d_k value here.
+				// For every value im iterating over I need sth
+			},start,stop);
+
+			// Check
+		}
 		
 
 	}
diff --git a/lib/core/c++/particle/aabb.hpp b/lib/core/c++/particle/aabb.hpp
new file mode 100644
index 0000000..aec95ca
--- /dev/null
+++ b/lib/core/c++/particle/aabb.hpp
@@ -0,0 +1,49 @@
+#pragma once
+
+#include "particle.hpp"
+
+namespace kel {
+namespace lbm {
+template<typename T, uint64_t D, typename PColl>
+class particle_aabb final {
+};
+
+template<typename T, uint64_t D, typename saw::native_data_type<T>::type radius>
+class particle_aabb<ParticleGroup<T,D,sch::ParticleCollisionSpheroid<T,radius> > > final {
+public:
+	using Schema = sch::ParticleGroup<T,D,sch::ParticleCollisionSpheroid<T,radius>>;
+
+	using AABB = Struct<
+		Member<sch::FixedArray<sch::UInt64,D>"a">,
+		Member<sch::FixedArray<sch::UInt64,D>"b">
+	>;
+public:
+	static constexpr saw::data<AABB> get(const saw::data<Schema>& p_grp, const saw::data<sch::FixedArray<sch::UInt64,1u>>& i, const saw::data<sch::FixedArray<sch::UInt64,D>>& meta){
+		auto& parts = p_grp.template get<"particles">();
+
+		auto& pi = parts.at(i);
+		auto& pirb = pi.template get<"rigid_body">();
+		auto& pirb_pos = pirb.template get<"position">();
+
+		saw::data<AABB> aabb;
+		auto& a = aabb.template get<"a">();
+		auto& b = aabb.template get<"b">();
+
+		saw::data<sch::Scalar<T>> rad_d;
+		rad_d.at({}).set(radius);
+
+		saw::data<sch::Vector<T,D>> lower;
+		saw::data<sch::Vector<T,D>> upper;
+
+		for(uint64_t i{0u}; i < D; ++i){
+			lower.at({{i}}) = pirb_pos.at({{i}}) >= rad_d.at({}) ? (pirb_pos.at({{i}}) - rad_d.at({})) : saw::data<T>{0};
+			a.at({i}) = lower.at({{i}}).template cast_to<sch::UInt64>();
+			upper.at({{i}}) = pirb_pos.at({{i}}) + rad_d.at({});
+			b.at({i}) = (upper.at({{i}})+saw::data<T>{1}).template cast_to<sch::UInt64>()
+		}
+		
+		return aabb;
+	}
+};
+}
+}
diff --git a/lib/core/c++/particle/porosity.hpp b/lib/core/c++/particle/porosity.hpp
index aa1ce5b..39d9652 100644
--- a/lib/core/c++/particle/porosity.hpp
+++ b/lib/core/c++/particle/porosity.hpp
@@ -8,7 +8,9 @@ namespace lbm {
 template<typename T, uint64_t D, typename Coll>
 class particle_porosity {
 public:
-	saw::data<sch::Scalar<T>> calculate(const saw::data<>& part_group, uint64_t p_i, const saw::data<sch::Vector<T,D>>& lbm_pos){
+
+	
+	saw::data<sch::Scalar<T>> calculate(const saw::data<sch::ParticleGroup<T,D,Coll>>& part_group, uint64_t p_i, const saw::data<sch::Vector<T,D>>& lbm_pos){
 		auto& mask = part_group.template get<"mask">();
 
 		auto& particles = part_group.template get<"particles">();
@@ -17,7 +19,7 @@ public:
 		auto& part_i_rb = part_i.template get<"rigid_body">();
 		auto& pirb = part_i_rb.template get<"position">();
 
-		auto& dist = lbm_pos = lbm_pos - pirb;
+		auto dist = lbm_pos - pirb;
 
 		// index 0 is at 
 
@@ -26,25 +28,58 @@ public:
 };
 
 
-template<typename T, uint64_t D, typename saw::native_data_type<T>::type radius>
-class particle_porosity<T, D, coll::ParticleCollisionSpheroid<T,radius>> final {
+template<typename T, uint64_t D, typename saw::native_data_type<T>::type radius, typename saw::native_data_type<T>::type eps>
+class particle_porosity<T, D, coll::ParticleCollisionSpheroid<T,radius, eps>> final {
 public:
-	saw::data<sch::Scalar<T>> calculate(const saw::data<sch::Particle>&, uint64_t i, const saw::data<sch::Vector<T,D>>& lbm_pos){
+	saw::data<sch::Scalar<T>> calculate(const saw::data<sch::ParticleGroup<T,D,sch::ParticleCollisionSpheroid<T,radius,eps> > >& part_group, uint64_t i, const saw::data<sch::Vector<T,D>>& lbm_pos){
 		saw::data<sch::Scalar<T>> por;
 		por.at({});
 
-		saw::data<sch::Scalar<T>> dps_2;
+		auto& parts = part_group.template get<"particles">();
+		auto& pi = parts.at({i});
+		auto& pi_rb = pi.template get<"rigid_body">();
+
+		auto& pi_rb_pos = pi_rb.template get<"position">();
+
+		// Basically the queried position minus the center of the particle
+		auto dist = lbm_pos - pi_rb_pos;
+
+		saw::data<sch::Scalar<T>> dist_len;
 		for(uint64_t i{0u}; i < D; ++i){
-			auto& dps_i = lbm_pos.at({{i}});
-			dps_2.at({}) = dps_i * dps_i;
+			auto& d_i = dist.at({{i}});
+			dist_len.at({}) = d_i * d_i;
 		}
+		dist_len.at({}).set(std::sqrt(dist_len.at({}).get());
 
-		saw::data<sch::Scalar<T>> rad_2;
-		rad_2.at({}).set(radius*radius);
+		saw::data<sch::Scalar<T>> rad_d{radius};
+		saw::data<sch::Scalar<T>> eps_half{eps *0.5};
+		
+		saw::data<sch::Scalar<T>> rad_d_eps_p = rad_d + eps_half;
+		saw::data<sch::Scalar<T>> rad_d_eps_n = rad_d - eps_half;
+
+		// saw::data<sch::Scalar<T>> rad_d_eps_p_2 = rad_d_eps_p * rad_d_eps_p;
+		// saw::data<sch::Scalar<T>> rad_d_eps_n_2 = rad_d_eps_n * rad_d_eps_n;
+		// saw::data<sch::Scalar<T>> rad_2;
+		// rad_2 = rad_d * rad_d;
 
 		saw::data<sch::Scalar<T>> inside;
-		if(dps_2.at({}).get() < rad_2.at({}).get()){
+		if(dist_len.at({}) <= rad_d_eps_n.at({})){
 			inside.at({}).set(1);
+			return inside;
+		}
+		if(dist_len.at({}) > rad_d_eps_p.at({})){
+			inside.at({}).set(0);
+			return inside
+		}
+
+		/*
+		 * cos^2 ( ||x-X(t)||_2 - (R-eps/2) )
+		 */
+		{
+			typename saw::native_data_type<T>::type inner = (std::pi / ( 2.0 * eps )) * (dist_len - rad_d_eps_n).at({}).get();
+			auto cos_inner = std::cos(inner);
+			auto cos_i_2 = cos_inner * cos_inner;
+			inside.at({}).set(cos_i_2);
 		}
 		return inside;
 	}