Add pybind11 wrappings for Imath::Frustum

Fix for issue AcademySoftwareFoundation#428 

Created a pybind11 wrapping file based on the specified template. Requires further testing, as this is my first time using pybind11.

Signed-off-by: Nikhil Mishra <[email protected]>

src/pybind11/PyBindImath/PyBindImathFrustum

@@ -0,0 +1,55 @@
+#include "PyBindImath.h"
+#include <ImathFrustum.h>
+#include <ImathVec.h>
+#include <ImathMatrix.h>
+
+namespace PyBindImath {
+
+template <class T, class V, class M>
+void register_frustum(pybind11::module& m, const char *name)
+{
+    pybind11::class_<T> c(m, name);
+    c.def(pybind11::init<>(), "Uninitialized by default")
+    .def(pybind11::init<T>(), pybind11::arg("frustum"), "Copy constructor")
+    .def(pybind11::init<S>(), pybind11::arg("nearPlane"), pybind11::arg("farPlane"), pybind11::arg("fovx"), pybind11::arg("aspect"), "Initialize with basic frustum properties")
+
+    .def_readwrite("nearPlane", &T::nearPlane, "The near clipping plane")
+    .def_readwrite("farPlane", &T::farPlane, "The far clipping plane")
+    .def_readwrite("fovx", &T::fovx, "The field of view in x direction")
+    .def_readwrite("aspect", &T::aspect, "The aspect ratio")
+
+    .def("set", pybind11::overload_cast<S, S, S, S>(&T::set), pybind11::arg("nearPlane"), pybind11::arg("farPlane"), pybind11::arg("fovx"), pybind11::arg("aspect"), "Set frustum properties")
+    .def("projectionMatrix", &T::projectionMatrix, "Returns the projection matrix of the frustum")
+    .def("transform", &T::transform, pybind11::arg("matrix"), "Applies a transformation matrix to the frustum")
+    .def("intersects", [](T& self, const V& point) {
+                bool result = self.intersects(point);
+                return result;
+            }, pybind11::arg("point"), "Determines if the point is inside the frustum")
+
+    .def("screenToWorld", [](T& self, const V& screenPoint) {
+                V worldPoint;
+                self.screenToWorld(screenPoint, worldPoint);
+                return worldPoint;
+            }, pybind11::arg("screenPoint"), "Convert a screen space point to world space")
+
+    .def("worldToScreen", [](T& self, const V& worldPoint) {
+                V screenPoint;
+                self.worldToScreen(worldPoint, screenPoint);
+                return screenPoint;
+            }, pybind11::arg("worldPoint"), "Convert a world space point to screen space")
+
+    .def("__str__", [](const T &obj) {
+            std::stringstream ss;
+            ss << obj;
+            return ss.str();
+        });
+}
+
+void register_imath_frustum(pybind11::module &m) 
+{
+    register_frustum<Imath::Frustumf, Imath::V3f, Imath::M44f>(m, "Frustumf");
+    register_frustum<Imath::Frustumd, Imath::V3d, Imath::M44d>(m, "Frustumd");
+}
+
+}
+