libformfactor 0.3.1 (new formula)

libformfactor is A C++ library for the efficient computation of scattering form
factors of arbitrary polyhedra according to
Wuttke, J. Appl. Cryst. 54, 580-587 (2021).

Homepage: <https://jugit.fz-juelich.de/mlz/libformfactor/>

Formula/lib/libformfactor.rb

@@ -0,0 +1,67 @@
+class Libformfactor < Formula
+  desc "C++ library for the efficient computation of scattering form factors"
+  homepage "https://jugit.fz-juelich.de/mlz/libformfactor"
+  url "https://jugit.fz-juelich.de/mlz/libformfactor/-/archive/v0.3.1/libformfactor-v0.3.1.tar.bz2"
+  sha256 "fc629a3e843e920b250393b0072f6673e26783b0776e8f08523534875950f298"
+  license "GPL-3.0-or-later"
+
+  depends_on "cmake" => :build
+  depends_on "libheinz"
+
+  def install
+    system "cmake", "-S", ".", "-B", "build",
+                    "-DLibHeinz_DIR=#{Formula["libheinz"].opt_prefix}/cmake",
+                    *std_cmake_args
+    system "cmake", "--build", "build"
+    system "cmake", "--install", "build"
+  end
+
+  test do
+    (testpath/"fftest.cpp").write <<~CPP
+      #include <ff/Face.h>
+      #include <ff/Prism.h>
+      #include <ff/Polyhedron.h>
+      #include <cmath>  // abs
+
+      bool CHECK_NEAR(const double value, const double expected, const double tol)
+      {
+        return std::abs(value - expected) <= tol;
+      }
+
+      bool test_asPolyhedron_prism()
+      {
+        ff::Prism prism(false, 1, {{-0.5, -0.5, 0}, {-0.5, 0.5, 0}, {0.5, 0.5, 0}, {0.5, -0.5, 0}});
+        ff::Polyhedron* polyhedron = prism.asPolyhedron();
+
+        const bool test0 = (polyhedron->faces().size() == 6);
+        const bool test1 = CHECK_NEAR(polyhedron->vertices()[4].z(), 0.5, 1E-13);
+        const bool test2 = CHECK_NEAR(polyhedron->vertices()[5].z(), 0.5, 1E-13);
+        const bool test3 = CHECK_NEAR(polyhedron->vertices()[6].z(), 0.5, 1E-13);
+        const bool test4 = CHECK_NEAR(polyhedron->vertices()[7].z(), 0.5, 1E-13);
+
+        return test0 && test1 && test2 && test3 && test4;
+      }
+
+      bool test_faceCenter_CenteredRectangle()
+      {
+        // FaceCenter:CenteredRectangle
+        ff::Face face({{-0.5, -1.4, 0}, {-0.5, 1.4, 0}, {0.5, 1.4, 0}, {0.5, -1.4, 0}}, true);
+        const R3 center = face.center_of_polygon();
+        const bool test1 = std::abs(center.x()) <= 1e-13;
+        const bool test2 = std::abs(center.y()) <= 1e-13;
+        const bool test3 = std::abs(center.z()) <= 1e-13;
+
+        return test1 && test2 && test3;
+      }
+
+      int main()
+      {
+        const bool all_tests = test_asPolyhedron_prism() && test_faceCenter_CenteredRectangle();
+        return all_tests? 0 : 1;
+      }
+    CPP
+
+    system ENV.cxx, "-std=c++17", "fftest.cpp", "-I#{include}", "-L#{lib}", "-lformfactor", "-o", "fftest"
+    system "./fftest"
+  end
+end