From dcee24278ed28d21cd3addffeeb8e5f9f7248602 Mon Sep 17 00:00:00 2001
From: "Claudius \"keldu\" Holeksa" <mail@keldu.de>
Date: Tue, 17 Feb 2026 18:29:22 +0100
Subject: End of day

---
 examples/poiseulle_3d_gpu/sim.cpp           | 16 ++++----
 examples/poiseulle_particles_2d_gpu/sim.cpp | 16 ++++----
 lib/core/c++/descriptor.hpp                 | 10 +++--
 lib/core/c++/environment.hpp                |  1 +
 lib/core/c++/equilibrium.hpp                |  3 +-
 lib/core/c++/lbm.hpp                        |  1 +
 lib/core/c++/memory.hpp                     | 62 +++++++++++++++++++++++++++++
 lib/core/c++/write_vtk.hpp                  | 22 +++++++++-
 lib/core/tests/memory.cpp                   | 18 +++++++++
 lib/core/tests/particles.cpp                | 23 +++++++++++
 10 files changed, 148 insertions(+), 24 deletions(-)
 create mode 100644 lib/core/c++/memory.hpp
 create mode 100644 lib/core/tests/memory.cpp

diff --git a/examples/poiseulle_3d_gpu/sim.cpp b/examples/poiseulle_3d_gpu/sim.cpp
index 27e5297..624566f 100644
--- a/examples/poiseulle_3d_gpu/sim.cpp
+++ b/examples/poiseulle_3d_gpu/sim.cpp
@@ -265,16 +265,20 @@ saw::error_or<void> lbm_main(int argc, char** argv){
 		}
 	}
 
-	converter<sch::Float64> conv {
+	converter<T> conv {
 		// delta_x
 		{{1.0}},
 		// delta_t
 		{{1.0}}
 	};
 
+	print_lbm_meta<T,Desc>(conv,{0.01});
+
 	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::FixedArray<sch::Particle<T,Desc::D>, particle_size>>>();
+	
+	std::cout<<"Estimated Bytes: "<<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()){
@@ -335,10 +339,7 @@ saw::error_or<void> lbm_main(int argc, char** argv){
 	for(saw::data<sch::UInt64> i{0u}; i < time_steps and krun; ++i){
 		{
 			{
-				std::string file_name = "t_";
-				file_name += std::to_string(i.get());
-				file_name += ".vtk";
-				auto eov = write_vtk_file(out_dir/file_name, *lbm_macro_data_ptr);
+				auto eov = write_vtk_file(out_dir,"t",i.get(),*lbm_macro_data_ptr);
 				if(eov.is_error()){
 					return eov;
 				}
@@ -380,10 +381,7 @@ saw::error_or<void> lbm_main(int argc, char** argv){
 	}
 	sycl_q.wait();
 	{
-		std::string file_name = "t_";
-		file_name += std::to_string(time_steps.get());
-		file_name += ".vtk";
-		auto eov = write_vtk_file(out_dir/file_name, *lbm_macro_data_ptr);
+		auto eov = write_vtk_file(out_dir,"t",time_steps.get(),*lbm_macro_data_ptr);
 		if(eov.is_error()){
 			return eov;
 		}
diff --git a/examples/poiseulle_particles_2d_gpu/sim.cpp b/examples/poiseulle_particles_2d_gpu/sim.cpp
index d12b7f5..de2bb40 100644
--- a/examples/poiseulle_particles_2d_gpu/sim.cpp
+++ b/examples/poiseulle_particles_2d_gpu/sim.cpp
@@ -264,17 +264,21 @@ saw::error_or<void> lbm_main(int argc, char** argv){
 		}
 	}
 
-	converter<sch::Float64> conv {
+	converter<T> conv {
 		// delta_x
 		{{1.0}},
 		// delta_t
 		{{1.0}}
 	};
+	
+	print_lbm_meta<T,Desc>(conv,{0.01});
 
 	// 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::FixedArray<sch::Particle<T,Desc::D>, particle_size>>>();
+	
+	std::cout<<"Estimated Bytes: "<<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()){
@@ -335,10 +339,7 @@ saw::error_or<void> lbm_main(int argc, char** argv){
 	for(saw::data<sch::UInt64> i{0u}; i < time_steps and krun; ++i){
 		{
 			{
-				std::string file_name = "t_";
-				file_name += std::to_string(i.get());
-				file_name += ".vtk";
-				auto eov = write_vtk_file(out_dir/file_name, *lbm_macro_data_ptr);
+				auto eov = write_vtk_file(out_dir,"t",i.get(), *lbm_macro_data_ptr);
 				if(eov.is_error()){
 					return eov;
 				}
@@ -380,10 +381,7 @@ saw::error_or<void> lbm_main(int argc, char** argv){
 	}
 	sycl_q.wait();
 	{
-		std::string file_name = "t_";
-		file_name += std::to_string(time_steps.get());
-		file_name += ".vtk";
-		auto eov = write_vtk_file(out_dir/file_name, *lbm_macro_data_ptr);
+		auto eov = write_vtk_file(out_dir,"t",time_steps.get(), *lbm_macro_data_ptr);
 		if(eov.is_error()){
 			return eov;
 		}
diff --git a/lib/core/c++/descriptor.hpp b/lib/core/c++/descriptor.hpp
index 9cc2591..e38daee 100644
--- a/lib/core/c++/descriptor.hpp
+++ b/lib/core/c++/descriptor.hpp
@@ -180,6 +180,7 @@ public:
 
 	static constexpr std::array<std::array<int32_t, D>, Q> directions = {{
 		{ 0, 0, 0},  // 0
+		// Into 1D
 		{-1, 0, 0},  // 1
 		{ 1, 0, 0},  // 2
 		// Expand into 2D
@@ -212,14 +213,17 @@ public:
 
 	static constexpr std::array<typename saw::native_data_type<T>::type,Q> weights = {
 		8./27.,
-		1./9.,
-		1./9.,
-		1./9.,
+		// 1D
+		2./27.,
+		2./27.,
+		// 2D
+		2./27.,
 		1./9.,
 		1./36.,
 		1./36.,
 		1./36.,
 		1./36.,
+		// 3D
 		8./27.,
 		1./9.,
 		1./9.,
diff --git a/lib/core/c++/environment.hpp b/lib/core/c++/environment.hpp
index 4915e3a..9e587d0 100644
--- a/lib/core/c++/environment.hpp
+++ b/lib/core/c++/environment.hpp
@@ -20,5 +20,6 @@ saw::error_or<std::filesystem::path> output_directory(){
 
 	return std::filesystem::path{home_dir} / ".lbm";
 }
+
 }
 }
diff --git a/lib/core/c++/equilibrium.hpp b/lib/core/c++/equilibrium.hpp
index 7d1324e..eb2b043 100644
--- a/lib/core/c++/equilibrium.hpp
+++ b/lib/core/c++/equilibrium.hpp
@@ -9,6 +9,7 @@ saw::data<sch::FixedArray<T, Descriptor::Q>> equilibrium(saw::data<sch::Scalar<T
 	using dfi = df_info<T, Descriptor>;
 
 	saw::data<sch::FixedArray<T,Descriptor::Q>> eq;
+	// Brain broken, here's an owl
 	//   ^
 	//  0.0
 	//  / \
@@ -23,7 +24,7 @@ saw::data<sch::FixedArray<T, Descriptor::Q>> equilibrium(saw::data<sch::Scalar<T
 	/**
 	 * Calculate equilibrium
 	 */
-	for(uint64_t i = 0u; i < eq.template get_dim_size<0u>(); ++i){
+	for(uint64_t i = 0u; i < Descriptor::Q; ++i){
 		saw::data<T> vel_c{};
 		for(uint64_t j = 0u; j < Descriptor::D; ++j){
 			// <vel,c_i>_2
diff --git a/lib/core/c++/lbm.hpp b/lib/core/c++/lbm.hpp
index 24f93f1..df89a69 100644
--- a/lib/core/c++/lbm.hpp
+++ b/lib/core/c++/lbm.hpp
@@ -14,6 +14,7 @@
 #include "iterator.hpp"
 #include "hlbm.hpp"
 #include "macroscopic.hpp"
+#include "memory.hpp"
 #include "stream.hpp"
 #include "write_vtk.hpp"
 #include "util.hpp"
diff --git a/lib/core/c++/memory.hpp b/lib/core/c++/memory.hpp
new file mode 100644
index 0000000..b6a089e
--- /dev/null
+++ b/lib/core/c++/memory.hpp
@@ -0,0 +1,62 @@
+#pragma once
+
+#include "common.hpp"
+#include "chunk.hpp"
+
+namespace kel {
+namespace lbm {
+
+namespace impl {
+
+template<typename Sch>
+struct memory_size_helper;
+
+template<typename Sch, uint64_t N>
+struct memory_size_helper<sch::Primitive<Sch,N>> {
+	static constexpr uint64_t bytes = N;
+};
+
+template<typename Sch, uint64_t... N>
+struct memory_size_helper<sch::FixedArray<Sch,N...>> {
+	static constexpr uint64_t bytes = saw::ct_multiply<uint64_t,N...>::value * memory_size_helper<Sch>::bytes;
+};
+
+template<typename Sch, uint64_t Ghost, uint64_t... N>
+struct memory_size_helper<sch::Chunk<Sch,Ghost,N...>> {
+	static constexpr uint64_t bytes = memory_size_helper<typename sch::Chunk<Sch,Ghost,N...>::InnerSchema>::bytes;
+};
+
+template<typename... T>
+class memory_estimate_helper final {
+private:
+
+	template<uint64_t i>
+	static void apply_i(saw::data<sch::UInt64>& bytes){
+
+		if constexpr ( i < sizeof...(T)){
+			using T_I = typename saw::parameter_pack_type<i,T...>::type;
+
+			bytes.set(bytes.get() + memory_size_helper<T_I>::bytes);
+
+			apply_i<i+1u>(bytes);
+		}
+	}
+
+public:
+
+	static void apply(saw::data<sch::UInt64>& bytes){
+		apply_i<0u>(bytes);
+	}
+};
+}
+
+template<typename... T>
+saw::data<sch::UInt64> memory_estimate(){
+	saw::data<sch::UInt64> bytes;
+
+	impl::memory_estimate_helper<T...>::apply(bytes);
+
+	return bytes;
+}
+}
+}
diff --git a/lib/core/c++/write_vtk.hpp b/lib/core/c++/write_vtk.hpp
index f7b8f8f..f925361 100644
--- a/lib/core/c++/write_vtk.hpp
+++ b/lib/core/c++/write_vtk.hpp
@@ -222,9 +222,27 @@ struct lbm_vtk_writer<sch::Struct<sch::Member<sch::Chunk<MemberT,Ghost,Dims...>,
 }
 
 template<typename Sch>
-saw::error_or<void> write_vtk_file(const std::filesystem::path& file_name, const saw::data<Sch>& field){
+saw::error_or<void> write_vtk_file(const std::filesystem::path& out_dir, const std::string_view& file_name, uint64_t d_t, const saw::data<Sch>& field){
+
+	auto vtk_dir = out_dir / "vtk";
+	{
+		std::error_code ec;
+		std::filesystem::create_directories(vtk_dir,ec);
+		if(ec != std::errc{}){
+			return saw::make_error<saw::err::critical>("Could not create directory for write_vtk_file function");
+		}
+	}
+	std::string ft_name{file_name};
+
+	std::stringstream sstr;
+	sstr
+		<<file_name
+		<<"_"
+		<<d_t
+		<<".vtk"
+	;
 
-	std::ofstream vtk_file{file_name};
+	std::ofstream vtk_file{vtk_dir / sstr.str() };
 
 	if( not vtk_file.is_open() ){
 		return saw::make_error<saw::err::critical>("Could not open file.");
diff --git a/lib/core/tests/memory.cpp b/lib/core/tests/memory.cpp
new file mode 100644
index 0000000..27cd938
--- /dev/null
+++ b/lib/core/tests/memory.cpp
@@ -0,0 +1,18 @@
+#include <forstio/test/suite.hpp>
+
+#include "../c++/memory.hpp"
+
+namespace {
+namespace sch {
+using namespace saw::schema;
+}
+
+SAW_TEST("Memory Estimate"){
+	using namespace kel::lbm;
+
+	SAW_EXPECT((memory_estimate<sch::Float32>().get() == 4u), std::string{"Float32 isn't 4 bytes, but "} + std::to_string(memory_estimate<sch::Float32>().get()) );
+	SAW_EXPECT((memory_estimate<sch::FixedArray<sch::Float32,5u,3u>>().get() == 60u), "FixedArray<Float32,5u,3u> isn't 60 bytes");
+	SAW_EXPECT((memory_estimate<sch::FixedArray<sch::Float32,5u,3u>, sch::UInt8>().get() == 61u), "FixedArray<Float32,5u,3u> + UInt8 isn't 61 bytes");
+}
+
+}
diff --git a/lib/core/tests/particles.cpp b/lib/core/tests/particles.cpp
index b2581f7..fcca19a 100644
--- a/lib/core/tests/particles.cpp
+++ b/lib/core/tests/particles.cpp
@@ -150,6 +150,29 @@ SAW_TEST("Moving particles 2D"){
 	SAW_EXPECT(has_collided, "Expecting collision within those steps");
 }
 
+SAW_TEST("Particle Matrix Rotation"){
+	using namespace kel;
+
+	saw::data<sch::Particle<sch::T,2u>> part_a;
+	{
+		auto& body = part_a.template get<"rigid_body">();
+		auto& pos = body.template get<"position">();
+		auto& pos_old = body.template get<"position_old">();
+		auto& coll = part_a.template get<"collision">();
+		auto& radius = coll.template get<"radius">();
+		auto& acc = body.template get<"acceleration">();
+
+		radius.set(1.0);
+
+		pos.at({{0u}}) = -5.0;
+		pos.at({{1u}}) = 0.2;
+		pos_old = pos;
+	}
+
+	
+
+}
+
 SAW_TEST("Particle Collision Impulse"){
 	using namespace kel;
 
-- 
cgit v1.2.3