New shape: Quarterpipe

doc/sphinx/constraints.rst

@@ -51,6 +51,7 @@ Available shapes are listed below.
     - :class:`espressomd.shapes.SpheroCylinder`
     - :class:`espressomd.shapes.Torus`
     - :class:`espressomd.shapes.HollowConicalFrustum`
+    - :class:`espressomd.shapes.Quarterpipe`
     - :class:`espressomd.shapes.Union`
 
 
@@ -450,6 +451,35 @@ Note: in the OpenGL visualizer, if the OpenGL Extrusion library is not available
 the shape surface will be rendered with dots.
 
 
+Quarterpipe
+""""""""""""
+
+:class:`espressomd.shapes.Quarterpipe`
+
+A quarterpipe which can be used to connect two walls or rhomboids in a smooth way.
+The shape is constructed by removing a quarter cylinder of radius ``radius``
+from a cuboid with side length ``radius``.
+It can be created via ::
+
+    shape=espressomd.shapes.Quarterpipe(center=[25]*3, axis=[1, 0, 0],
+                                        orientation=[0, 1, 1], radius=25,
+                                        height=30)
+
+A cross section with an explanation of the parameters is shown in the figure below.
+The three-dimensional shape is an extrusion of this profile.
+
+.. figure:: figures/quarterpipe.png
+   :alt: Cross section of the quarterpipe shape.
+   :height: 4.00000cm
+
+``center`` defines the  center of the cylinder. 
+``axis`` is the axis of the cylinder, orthogonal to the curve of the pipe.
+``orientation`` points from ``center`` along the symmetry axis of the quarterpipe.
+``radius`` is the radius of the pipe.
+``height`` is the extent of the shape along ``axis`` (symmetric in both directions
+starting from ``center``).
+
+
 Union
 """""
 

samples/visualization_constraints.py

@@ -30,7 +30,7 @@
 group.add_argument("--wall", action="store_const", dest="shape", const="Wall",
                    default="Wall")
 for shape in ("Sphere", "Ellipsoid", "Cylinder", "SpheroCylinder", "Torus",
-              "SimplePore", "Slitpore", "HollowConicalFrustum"):
+              "SimplePore", "Slitpore", "HollowConicalFrustum", "Quarterpipe"):
     group.add_argument("--" + shape.lower(), action="store_const",
                        dest="shape", const=shape)
 args = parser.parse_args()
@@ -107,6 +107,14 @@
                                       direction=1, radius=15, tube_radius=6),
         particle_type=0, penetrable=True)
 
+elif args.shape == "Quarterpipe":
+    system.constraints.add(
+        shape=espressomd.shapes.Quarterpipe(center=[25, 3, 3], axis=[1, 0, 0],
+                                            orientation=[0, 1, 1], radius=40,
+                                            height=50),
+        particle_type=0, penetrable=True)
+
+
 else:
     raise ValueError("Unknown shape '{}'".format(args.shape))
 

src/python/espressomd/shapes.py

@@ -24,6 +24,28 @@ class Shape:
     _so_bind_methods = ("calc_distance",)
 
 
+@script_interface_register
+class Quarterpipe(Shape, ScriptInterfaceHelper):
+    """
+    A quarterpipe, built by subtracting a ``pi/2`` segment of a cylinder from a cuboid
+
+    Attributes
+    ----------
+    center : (3,) array_like of :obj:`float`
+        Coordinates of the center of the quarterpipe.
+    axis : (3,) array_like of :obj:`float`
+        Axis of the cylinder.
+    orientation : (3,) array_like of :obj:`float`
+        direction in which the quarterpipe points from center
+    radius : :obj:`float`
+        Radius of the pipe.
+    height : :obj:`float`
+        height of the quarterpipe along ``axis``
+
+    """
+    _so_name = "Shapes::Quarterpipe"
+
+
 @script_interface_register
 class Cylinder(Shape, ScriptInterfaceHelper):
     """

src/script_interface/shapes/Quarterpipe.hpp

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2010-2019 The ESPResSo project
+ *
+ * This file is part of ESPResSo.
+ *
+ * ESPResSo is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * ESPResSo is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef ESPRESSO_QUARTERPIPE_HPP
+#define ESPRESSO_QUARTERPIPE_HPP
+#include "Shape.hpp"
+#include <shapes/Quarterpipe.hpp>
+
+namespace ScriptInterface {
+namespace Shapes {
+
+class Quarterpipe : public Shape {
+public:
+  Quarterpipe() : m_quarterpipe(new ::Shapes::Quarterpipe()) {
+    add_parameters({{"center",
+                     [this](Variant const &v) {
+                       m_quarterpipe->set_center(get_value<Utils::Vector3d>(v));
+                     },
+                     [this]() { return m_quarterpipe->center(); }},
+
+                    {"axis",
+                     [this](Variant const &v) {
+                       m_quarterpipe->set_axis(get_value<Utils::Vector3d>(v));
+                     },
+                     [this]() { return m_quarterpipe->axis(); }},
+
+                    {"orientation",
+                     [this](Variant const &v) {
+                       m_quarterpipe->set_orientation(
+                           get_value<Utils::Vector3d>(v));
+                     },
+                     [this]() { return m_quarterpipe->orientation(); }},
+
+                    {"radius",
+                     [this](Variant const &v) {
+                       m_quarterpipe->set_radius(get_value<double>(v));
+                     },
+                     [this]() { return m_quarterpipe->radius(); }},
+
+                    {"height",
+                     [this](Variant const &v) {
+                       m_quarterpipe->set_height(get_value<double>(v));
+                     },
+                     [this]() { return m_quarterpipe->height(); }}});
+  }
+
+  std::shared_ptr<::Shapes::Shape> shape() const override {
+    return m_quarterpipe;
+  }
+
+private:
+  std::shared_ptr<::Shapes::Quarterpipe> m_quarterpipe;
+};
+
+} /* namespace Shapes */
+} /* namespace ScriptInterface */
+
+#endif

src/script_interface/shapes/initialize.cpp

@@ -21,6 +21,7 @@
 #include "Ellipsoid.hpp"
 #include "HollowConicalFrustum.hpp"
 #include "NoWhere.hpp"
+#include "Quarterpipe.hpp"
 #include "Rhomboid.hpp"
 #include "SimplePore.hpp"
 #include "Slitpore.hpp"
@@ -35,6 +36,7 @@
 namespace ScriptInterface {
 namespace Shapes {
 void initialize(Utils::Factory<ObjectHandle> *f) {
+  f->register_new<Quarterpipe>("Shapes::Quarterpipe");
   f->register_new<HollowConicalFrustum>("Shapes::HollowConicalFrustum");
   f->register_new<Union>("Shapes::Union");
   f->register_new<NoWhere>("Shapes::NoWhere");

src/shapes/CMakeLists.txt

@@ -1,7 +1,7 @@
 set(SOURCE_FILES
-    src/HollowConicalFrustum.cpp src/Cylinder.cpp src/Ellipsoid.cpp
-    src/Rhomboid.cpp src/SimplePore.cpp src/Slitpore.cpp src/Sphere.cpp
-    src/SpheroCylinder.cpp src/Torus.cpp src/Wall.cpp)
+    src/Quarterpipe.cpp src/HollowConicalFrustum.cpp src/Cylinder.cpp
+    src/Ellipsoid.cpp src/Rhomboid.cpp src/SimplePore.cpp src/Slitpore.cpp
+    src/Sphere.cpp src/SpheroCylinder.cpp src/Torus.cpp src/Wall.cpp)
 
 add_library(EspressoShapes SHARED ${SOURCE_FILES})
 target_link_libraries(EspressoShapes PUBLIC EspressoUtils PRIVATE Boost::boost

src/shapes/include/shapes/Quarterpipe.hpp

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2017-2019 The ESPResSo project
+ *
+ * This file is part of ESPResSo.
+ *
+ * ESPResSo is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * ESPResSo is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef SHAPES_QUARTERPIPE_HPP
+#define SHAPES_QUARTERPIPE_HPP
+
+#include "Shape.hpp"
+#include <utils/Vector.hpp>
+#include <utils/constants.hpp>
+
+namespace Shapes {
+
+/**
+ * @brief Quarterpipe shape based on intersecting a cuboid
+ * with a cylinder
+ *
+ * \image html quarterpipe_detailed.png width=1000px
+ */
+
+class Quarterpipe : public Shape {
+public:
+  Quarterpipe()
+      : m_center{Utils::Vector3d{}}, m_axis{Utils::Vector3d{}},
+        m_orientation{Utils::Vector3d{}}, m_radius(0.), m_height(0.),
+        m_delta_phi(0.5 * Utils::pi()) {}
+
+  void set_center(Utils::Vector3d const &center) { m_center = center; }
+  void set_axis(Utils::Vector3d const &axis) {
+    auto axis_tmp(axis);
+    m_axis = axis_tmp.normalize();
+  }
+  void set_orientation(Utils::Vector3d const &orientation) {
+    auto orientation_tmp(orientation);
+    m_orientation = orientation_tmp.normalize();
+  }
+  void set_radius(double const radius) { m_radius = radius; }
+  void set_height(double const height) { m_height = height; }
+
+  Utils::Vector3d const &center() const { return m_center; }
+  Utils::Vector3d const &axis() const { return m_axis; }
+  Utils::Vector3d const &orientation() const { return m_orientation; }
+  double radius() const { return m_radius; }
+  double height() const { return m_height; }
+
+  void calculate_dist(const Utils::Vector3d &pos, double &dist,
+                      Utils::Vector3d &vec) const override;
+
+private:
+  Utils::Vector3d m_center;
+  Utils::Vector3d m_axis;
+  Utils::Vector3d m_orientation;
+  double m_radius;
+  double m_height;
+  double m_delta_phi;
+};
+} // namespace Shapes
+
+#endif