pybullet: add option to use NumPy to speed up, thanks to moof2k

option is disabled by default. When using cmake, use
cmake -DBUILD_PYBULLET=ON -DBUILD_PYBULLET_NUMPY=ON
then both testrender.py and testrender_np.py will work
without numpy only testrender.py works.
The numpy.reshape is likely a no-op when using numpy array,
so we could remove testrender_np.py...

See https://github.com/bulletphysics/bullet3/pull/774

CMakeLists.txt

@@ -194,11 +194,28 @@ ENDIF()
 
 OPTION(BUILD_BULLET3 "Set when you want to build Bullet 3" ON)
 
-FIND_PACKAGE(PythonLibs)
 OPTION(BUILD_PYBULLET "Set when you want to build pybullet (experimental Python bindings for Bullet)" OFF)
 
 
 IF(BUILD_PYBULLET)
+
+	FIND_PACKAGE(PythonLibs)
+
+	OPTION(BUILD_PYBULLET_NUMPY "Set when you want to build pybullet with NumPy support" OFF)
+
+	IF(BUILD_PYBULLET_NUMPY)	
+		set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${CMAKE_CURRENT_LIST_DIR}/build3/cmake)
+		#include(FindNumPy)
+		FIND_PACKAGE(NumPy)
+		if (PYTHON_NUMPY_FOUND)
+			message("NumPy found")
+			add_definitions(-DPYBULLET_USE_NUMPY)
+		else()
+			message("NumPy not found")
+		endif()
+	ENDIF()
+	OPTION(BUILD_PYBULLET "Set when you want to build pybullet (experimental Python bindings for Bullet)" OFF)
+
 	IF(WIN32)
 		SET(BUILD_SHARED_LIBS OFF CACHE BOOL "Shared Libs" FORCE)
 	ELSE(WIN32)

build3/cmake/FindNumPy.cmake

@@ -0,0 +1,41 @@
+# Find the Python NumPy package
+# PYTHON_NUMPY_INCLUDE_DIR
+# PYTHON_NUMPY_FOUND
+# will be set by this script
+
+cmake_minimum_required(VERSION 2.6)
+
+if(NOT PYTHON_EXECUTABLE)
+  if(NumPy_FIND_QUIETLY)
+    find_package(PythonInterp QUIET)
+  else()
+    find_package(PythonInterp)
+    set(__numpy_out 1)
+  endif()
+endif()
+
+if (PYTHON_EXECUTABLE)
+  # Find out the include path
+  execute_process(
+    COMMAND "${PYTHON_EXECUTABLE}" -c
+            "from __future__ import print_function\ntry: import numpy; print(numpy.get_include(), end='')\nexcept:pass\n"
+            OUTPUT_VARIABLE __numpy_path)
+  # And the version
+  execute_process(
+    COMMAND "${PYTHON_EXECUTABLE}" -c
+            "from __future__ import print_function\ntry: import numpy; print(numpy.__version__, end='')\nexcept:pass\n"
+    OUTPUT_VARIABLE __numpy_version)
+elseif(__numpy_out)
+  message(STATUS "Python executable not found.")
+endif(PYTHON_EXECUTABLE)
+
+find_path(PYTHON_NUMPY_INCLUDE_DIR numpy/arrayobject.h
+  HINTS "${__numpy_path}" "${PYTHON_INCLUDE_PATH}" NO_DEFAULT_PATH)
+
+if(PYTHON_NUMPY_INCLUDE_DIR)
+  set(PYTHON_NUMPY_FOUND 1 CACHE INTERNAL "Python numpy found")
+endif(PYTHON_NUMPY_INCLUDE_DIR)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(NumPy REQUIRED_VARS PYTHON_NUMPY_INCLUDE_DIR
+                                        VERSION_VAR __numpy_version)

examples/SharedMemory/PhysicsServerExample.cpp

@@ -1131,7 +1131,7 @@ void	PhysicsServerExample::vrControllerButtonCallback(int controllerId, int butt
 	else
 	{
 
-		if ((button == 33))
+		if (button == 33)
 		{
 			m_args[0].m_isVrControllerPicking[controllerId] = (state != 0);
 			m_args[0].m_isVrControllerReleasing[controllerId] = (state == 0);

examples/pybullet/CMakeLists.txt

@@ -5,6 +5,11 @@ INCLUDE_DIRECTORIES(
 		${BULLET_PHYSICS_SOURCE_DIR}/examples/ThirdPartyLibs
 		${PYTHON_INCLUDE_DIRS}
   )
+IF(BUILD_PYBULLET_NUMPY)
+	INCLUDE_DIRECTORIES(
+		${PYTHON_NUMPY_INCLUDE_DIR}
+	)
+ENDIF()
 
 SET(pybullet_SRCS
 	pybullet.c

examples/pybullet/pybullet.c

@@ -1821,7 +1821,11 @@ static PyMethodDef SpamMethods[] = {
     {"renderImage", pybullet_renderImage, METH_VARARGS,
      "Render an image (given the pixel resolution width, height, camera view "
      "matrix, projection matrix, near, and far values), and return the "
-     "8-8-8bit RGB pixel data and floating point depth values"},
+     "8-8-8bit RGB pixel data and floating point depth values"
+#ifdef PYBULLET_USE_NUMPY
+     " as NumPy arrays"
+#endif
+     },
 
     {"getContactPointData", pybullet_getContactPointData, METH_VARARGS,
      "Return the contact point information for all or some of pairwise "