1 files changed, 82 insertions, 0 deletions
diff --git a/tangle/ldc-2d.cu b/tangle/ldc-2d.cu
new file mode 100644
index 0000000..8989374
--- /dev/null
+++ b/tangle/ldc-2d.cu
@@ -0,0 +1,82 @@
+#include <LLBM/base.h>
+#include <LLBM/bulk.h>
+#include <LLBM/boundary.h>
+
+#include "util/render_window.h"
+#include "util/texture.h"
+#include "util/colormap.h"
+
+#include <LLBM/kernel/collect_moments.h>
+#include <LLBM/kernel/collect_velocity_norm.h>
+
+using T = float;
+using DESCRIPTOR = descriptor::D2Q9;
+
+int main() {
+cudaSetDevice(0);
+
+const descriptor::Cuboid<DESCRIPTOR> cuboid(500, 500);
+Lattice<DESCRIPTOR,T> lattice(cuboid);
+
+CellMaterials<DESCRIPTOR> materials(cuboid, [&cuboid](uint2 p) -> int {
+  if (p.x == 0 || p.y == 0 || p.x == cuboid.nX-1) {
+    return 2; // boundary cell
+  } else if (p.y == cuboid.nY-1) {
+    return 3; // lid cell
+  } else {
+    return 1; // bulk
+  }
+});
+
+auto bulk_mask = materials.mask_of_material(1);
+auto wall_mask = materials.mask_of_material(2);
+auto lid_mask  = materials.mask_of_material(3);
+
+lattice.apply(Operator(InitializeO(), bulk_mask),
+              Operator(InitializeO(), wall_mask),
+              Operator(InitializeO(), lid_mask));
+cudaDeviceSynchronize();
+
+const float tau = 0.51;
+const float u_lid = 0.05;
+
+RenderWindow window("LDC");
+cudaSurfaceObject_t colormap;
+ColorPalette palette(colormap);
+auto slice = [cuboid] __device__ (int iX, int iY) -> std::size_t {
+               return descriptor::gid(cuboid,iX,cuboid.nY-1-iY);
+             };
+DeviceBuffer<T> moments_rho(cuboid.volume);
+DeviceBuffer<T> moments_u(2*cuboid.volume);
+T* u = moments_u.device();
+std::size_t iStep = 0;
+
+while (window.isOpen()) {
+  lattice.apply(Operator(BgkCollideO(), bulk_mask, tau),
+                Operator(BounceBackO(), wall_mask),
+                Operator(BounceBackMovingWallO(), lid_mask, std::min(iStep*1e-3, 1.0)*u_lid, 0.f));
+  lattice.stream();
+  if (iStep % 100 == 0) {
+    cudaDeviceSynchronize();
+    lattice.inspect<CollectMomentsF>(bulk_mask, moments_rho.device(), moments_u.device());
+    renderSliceViewToTexture<<<
+      dim3(cuboid.nX / 32 + 1, cuboid.nY / 32 + 1),
+      dim3(32,32)
+    >>>(cuboid.nX, cuboid.nY,
+        slice,
+        [u,u_lid] __device__ (std::size_t gid) -> float {
+          return length(make_float2(u[2*gid+0], u[2*gid+1])) / u_lid;
+        },
+        [colormap] __device__ (float x) -> float3 {
+          return colorFromTexture(colormap, clamp(x, 0.f, 1.f));
+        },
+        window.getRenderSurface());
+    window.draw([&]() {
+      ImGui::Begin("Render");
+      palette.interact();
+      ImGui::End();
+    }, [](sf::Event&) { });
+  }
+  ++iStep;
+}
+}