copied everything over from 2012 and removed all of the actual robot code except the drivetrain stuff
git-svn-id: https://robotics.mvla.net/svn/frc971/2013/trunk/src@4078 f308d9b7-e957-4cde-b6ac-9a88185e7312
diff --git a/frc971/control_loops/python/libcdd.py b/frc971/control_loops/python/libcdd.py
new file mode 100644
index 0000000..a217728
--- /dev/null
+++ b/frc971/control_loops/python/libcdd.py
@@ -0,0 +1,129 @@
+#!/usr/bin/python
+
+"""Wrapper around libcdd, a polytope manipulation library."""
+
+__author__ = 'Austin Schuh (austin.linux@gmail.com)'
+
+import ctypes
+
+# Wrapper around PyFile_AsFile so that we can print out the error messages.
+# Set the arg type and return types of the function call.
+class FILE(ctypes.Structure):
+ pass
+
+ctypes.pythonapi.PyFile_AsFile.argtypes = [ctypes.py_object]
+ctypes.pythonapi.PyFile_AsFile.restype = ctypes.POINTER(FILE)
+
+# Load and init libcdd. libcdd is a C library that implements algorithm to
+# manipulate half space and vertex representations of polytopes.
+# Unfortunately, the library was compiled with C++ even though it has a lot of C
+# code in it, so all the symbol names are mangled. Ug.
+libcdd = ctypes.cdll.LoadLibrary('libcdd.so')
+libcdd._Z23dd_set_global_constantsv()
+
+# The variable type mytype that libcdd defines (double[1])
+# See http://docs.python.org/2/library/ctypes.html#arrays for the documentation
+# explaining why ctypes.c_double * 1 => double[1]
+# libcdd defines mytype to various things so it can essentially template its
+# functions. What a weird library.
+mytype = ctypes.c_double * 1
+
+
+# Forward declaration for the polyhedra data structure.
+class dd_polyhedradata(ctypes.Structure):
+ pass
+
+
+# Definition of dd_matrixdata
+class dd_matrixdata(ctypes.Structure):
+ _fields_ = [
+ ("rowsize", ctypes.c_long),
+ ("linset", ctypes.POINTER(ctypes.c_ulong)),
+ ("colsize", ctypes.c_long),
+ ("representation", ctypes.c_int),
+ ("numbtype", ctypes.c_int),
+ ("matrix", ctypes.POINTER(ctypes.POINTER(mytype))),
+ ("objective", ctypes.c_int),
+ ("rowvec", ctypes.POINTER(mytype)),
+ ]
+
+# Define the input and output types for a bunch of libcdd functions.
+libcdd._Z15dd_CreateMatrixll.restype = ctypes.POINTER(dd_matrixdata)
+libcdd._Z9ddd_get_dPd.argtypes = [mytype]
+libcdd._Z9ddd_get_dPd.restype = ctypes.c_double
+
+libcdd._Z17dd_CopyGeneratorsP16dd_polyhedradata.argtypes = [
+ ctypes.POINTER(dd_polyhedradata)
+]
+libcdd._Z17dd_CopyGeneratorsP16dd_polyhedradata.restype = ctypes.POINTER(dd_matrixdata)
+
+libcdd._Z16dd_DDMatrix2PolyP13dd_matrixdataP12dd_ErrorType.argtypes = [
+ ctypes.POINTER(dd_matrixdata),
+ ctypes.POINTER(ctypes.c_int)
+]
+libcdd._Z16dd_DDMatrix2PolyP13dd_matrixdataP12dd_ErrorType.restype = (
+ ctypes.POINTER(dd_polyhedradata))
+
+libcdd._Z13dd_FreeMatrixP13dd_matrixdata.argtypes = [
+ ctypes.POINTER(dd_matrixdata)
+]
+
+libcdd._Z16dd_FreePolyhedraP16dd_polyhedradata.argtypes = [
+ ctypes.POINTER(dd_polyhedradata)
+]
+
+libcdd._Z9ddd_set_dPdd.argtypes = [
+ mytype,
+ ctypes.c_double
+]
+
+
+# Various enums.
+DD_INEQUALITY = 1
+DD_REAL = 1
+DD_NO_ERRORS = 17
+
+
+def dd_CreateMatrix(rows, cols):
+ return libcdd._Z15dd_CreateMatrixll(
+ ctypes.c_long(rows),
+ ctypes.c_long(cols))
+
+
+def dd_set_d(mytype_address, double_value):
+ libcdd._Z9ddd_set_dPdd(mytype_address,
+ ctypes.c_double(double_value))
+
+
+def dd_CopyGenerators(polyhedraptr):
+ return libcdd._Z17dd_CopyGeneratorsP16dd_polyhedradata(polyhedraptr)
+
+
+def dd_get_d(mytype_address):
+ return libcdd._Z9ddd_get_dPd(mytype_address)
+
+
+def dd_FreeMatrix(matrixptr):
+ libcdd._Z13dd_FreeMatrixP13dd_matrixdata(matrixptr)
+
+
+def dd_FreePolyhedra(polyhedraptr):
+ libcdd._Z16dd_FreePolyhedraP16dd_polyhedradata(polyhedraptr)
+
+
+def dd_DDMatrix2Poly(matrixptr):
+ error = ctypes.c_int()
+ polyhedraptr = libcdd._Z16dd_DDMatrix2PolyP13dd_matrixdataP12dd_ErrorType(
+ matrixptr,
+ ctypes.byref(error))
+
+ # Return None on error.
+ # The error values are enums, so they aren't exposed.
+ if error.value != NO_ERRORS:
+ # Dump out the errors to stderr
+ libcdd._Z21dd_WriteErrorMessagesP8_IO_FILE12dd_ErrorType(
+ ctypes.pythonapi.PyFile_AsFile(ctypes.py_object(sys.stdout)),
+ error)
+ dd_FreePolyhedra(polyhedraptr)
+ return None
+ return polyhedraptr