initial pose transformation

still need to implement proper screw transformation matrices with rodrigues rotation

headeronly/linalg.h

@@ -1,3 +1,5 @@
+// Forked from: 
+
 // linalg.h - 2.2 - Single-header public domain linear algebra library
 //
 // The intent of this library is to provide the bulk of the functionality

tests/test_uvlm_theodorsen.cpp

@@ -0,0 +1,45 @@
+#include <vector>
+#include <string>
+#include <fstream>
+#include <cmath>
+#include <cstdio>
+
+#include "tinycombination.hpp"
+
+#include "vlm.hpp"
+#include "vlm_utils.hpp"
+
+using namespace vlm;
+
+int main(int argc, char **argv) {
+    const std::vector<std::string> meshes = {"../../../../mesh/infinite_rectangular_5x200.x"};
+    const std::vector<std::string> backends = get_available_backends();
+
+    auto solvers = tiny::make_combination(meshes, backends);
+
+    for (const auto& [mesh_name, backend_name] : solvers) {
+
+        auto translation = [&](f32 t) -> linalg::alias::float4x4 {
+            return linalg::translation_matrix(linalg::alias::float3{
+                -1.0f*t,
+                0.0f,
+                std::sin(0.2f * t)
+            });
+        };
+
+        // auto rotation = [&](f32 t) -> linalg::alias::float4x4 {
+        //     return linalg::translation_matrix(linalg::alias::float3{
+        //         -1.0f*t,
+        //         0.0f,
+        //         std::sin(0.2f * t)
+        //     });
+        // };
+
+        auto wing_pose = [&](f32 t) -> linalg::alias::float4x4 {
+            return translation(t);
+        };
+
+    }
+
+    return 0;
+}

vlm/include/vlm.hpp

@@ -44,4 +44,12 @@ class LinearVLM final: public Solver {
     AeroCoefficients solve(const FlowData& flow);
 };
 
+class UVLM final: public Solver {
+    public:
+    UVLM(const tiny::Config& cfg): Solver(cfg) {}
+    UVLM() = default;
+    ~UVLM() = default;
+    AeroCoefficients solve(const FlowData& flow);
+};
+
 } // namespace vlm

vlm/include/vlm_mesh.hpp

@@ -35,7 +35,7 @@ class Mesh {
     // ---------------------
     u64 nc = 1; // number of panels chordwise
     u64 ns = 1; // number of panels spanwise
-    const u64 nw = 1; // number of panels in chordwise wake
+    u64 nw = 1; // number of panels in chordwise wake
 
     // Analytical quanities when provided
     // ---------------------
@@ -83,5 +83,6 @@ class Mesh {
 
 // todo, update this to mirror the constructor
 std::unique_ptr<Mesh> create_mesh(const std::string& filename);
+void mesh_transform(Mesh& mesh, const linalg::alias::float4x4& transform);
 
 } // namespace vlm

vlm/src/vlm_mesh.cpp

@@ -367,4 +367,14 @@ void Mesh::io_read(const std::string& filename) {
     } else {
         throw std::runtime_error("Failed to open mesh file");
     }
+}
+
+void vlm::mesh_transform(Mesh& mesh, const linalg::alias::float4x4& transform) {
+    // like a functional map but over multidimensional elements
+    for (u64 i = 0; i < mesh.nb_vertices_wing(); i++) {
+        linalg::alias::float4 transformed_pt = linalg::mul(transform, linalg::alias::float4{mesh.v.x[i], mesh.v.y[i], mesh.v.z[i], 1.f});
+        mesh.v.x[i] = transformed_pt.x;
+        mesh.v.y[i] = transformed_pt.y;
+        mesh.v.z[i] = transformed_pt.z;
+    }
 }