Source code for pymunk.space

__docformat__ = "reStructuredText"

import weakref
from weakref import WeakSet
import platform
import copy

from . import _chipmunk_cffi
cp = _chipmunk_cffi.lib
ffi = _chipmunk_cffi.ffi    
    
from .vec2d import Vec2d
from .body import Body
from .collision_handler import CollisionHandler
from .query_info import PointQueryInfo, SegmentQueryInfo, ShapeQueryInfo
from .shapes import Shape, Circle, Poly, Segment
from .contact_point_set import ContactPointSet
from ._pickle import PickleMixin
from pymunk.constraint import Constraint


[docs]class Space(PickleMixin, object): """Spaces are the basic unit of simulation. You add rigid bodies, shapes and joints to it and then step them all forward together through time. A Space can be copied and pickled. Note that any post step callbacks are not copied. Also note that some internal collision cache data is not copied, which can make the simulation a bit unstable the first few steps of the fresh copy. Custom properties set on the space will also be copied/pickled. Any collision handlers will also be copied/pickled. Note that depending on the pickle protocol used there are some restrictions on what functions can be copied/pickled. Example:: >>> import pymunk, pickle >>> space = pymunk.Space() >>> space2 = space.copy() >>> space3 = pickle.loads(pickle.dumps(space)) """ _pickle_attrs_init = ['threaded'] _pickle_attrs_general = ['iterations', 'gravity', 'damping', 'idle_speed_threshold', 'sleep_time_threshold', 'collision_slop', 'collision_bias', 'collision_persistence', 'threads']
[docs] def __init__(self, threaded=False): """Create a new instance of the Space. If you set threaded=True the step function will run in threaded mode which might give a speedup. Note that even when you set threaded=True you still have to set Space.threads=2 to actually use more than one thread. Also note that threaded mode is not available on Windows, and setting threaded=True has no effect on that platform. """ self.threaded = threaded if self.threaded: self._space = ffi.gc(cp.cpHastySpaceNew(), cp.cpHastySpaceFree) else: self._space = ffi.gc(cp.cpSpaceNew(), cp.cpSpaceFree) self._handlers = {} # To prevent the gc to collect the callbacks. self._post_step_callbacks = {} self._removed_shapes = {} self._shapes = {} self._bodies = set() self._static_body = None self._constraints = set() self._in_step = False self._add_later = set() self._remove_later = set()
def _get_self(self): return self def _get_shapes(self): """A list of all the shapes added to this space (includes both static and non-static) """ return list(self._shapes.values()) shapes = property(_get_shapes, doc=_get_shapes.__doc__) def _get_bodies(self): return list(self._bodies) bodies = property(_get_bodies, doc="""A list of the bodies added to this space""") def _get_constraints(self): return list(self._constraints) constraints = property(_get_constraints, doc="""A list of the constraints added to this space""") def _get_static_body(self): """A dedicated static body for the space. You don't have to use it, but because its memory is managed automatically with the space its very convenient. """ if self._static_body == None: b = cp.cpSpaceGetStaticBody(self._space) self._static_body = Body._init_with_body(b) self._static_body._space = self return self._static_body static_body = property(_get_static_body, doc=_get_static_body.__doc__) def _set_iterations(self, value): cp.cpSpaceSetIterations(self._space, value) def _get_iterations(self): return cp.cpSpaceGetIterations(self._space) iterations = property(_get_iterations, _set_iterations , doc="""Iterations allow you to control the accuracy of the solver. Defaults to 10. Pymunk uses an iterative solver to figure out the forces between objects in the space. What this means is that it builds a big list of all of the collisions, joints, and other constraints between the bodies and makes several passes over the list considering each one individually. The number of passes it makes is the iteration count, and each iteration makes the solution more accurate. If you use too many iterations, the physics should look nice and solid, but may use up too much CPU time. If you use too few iterations, the simulation may seem mushy or bouncy when the objects should be solid. Setting the number of iterations lets you balance between CPU usage and the accuracy of the physics. Pymunk's default of 10 iterations is sufficient for most simple games. """) def _set_gravity(self, gravity_vector): cp.cpSpaceSetGravity(self._space, tuple(gravity_vector)) def _get_gravity(self): return Vec2d._fromcffi(cp.cpSpaceGetGravity(self._space)) gravity = property(_get_gravity, _set_gravity , doc="""Global gravity applied to the space. Defaults to (0,0). Can be overridden on a per body basis by writing custom integration functions. """) def _set_damping(self, damping): cp.cpSpaceSetDamping(self._space, damping) def _get_damping(self): return cp.cpSpaceGetDamping(self._space) damping = property(_get_damping, _set_damping , doc="""Amount of simple damping to apply to the space. A value of 0.9 means that each body will lose 10% of its velocity per second. Defaults to 1. Like gravity, it can be overridden on a per body basis. """) def _set_idle_speed_threshold(self, idle_speed_threshold): cp.cpSpaceSetIdleSpeedThreshold(self._space, idle_speed_threshold) def _get_idle_speed_threshold(self): return cp.cpSpaceGetIdleSpeedThreshold(self._space) idle_speed_threshold = property(_get_idle_speed_threshold , _set_idle_speed_threshold , doc="""Speed threshold for a body to be considered idle. The default value of 0 means the space estimates a good threshold based on gravity. """) def _set_sleep_time_threshold(self, sleep_time_threshold): cp.cpSpaceSetSleepTimeThreshold(self._space, sleep_time_threshold) def _get_sleep_time_threshold(self): return cp.cpSpaceGetSleepTimeThreshold(self._space) sleep_time_threshold = property(_get_sleep_time_threshold , _set_sleep_time_threshold , doc="""Time a group of bodies must remain idle in order to fall asleep. The default value of `inf` disables the sleeping algorithm. """) def _set_collision_slop(self, collision_slop): cp.cpSpaceSetCollisionSlop(self._space, collision_slop) def _get_collision_slop(self): return cp.cpSpaceGetCollisionSlop(self._space) collision_slop = property(_get_collision_slop , _set_collision_slop , doc="""Amount of overlap between shapes that is allowed. To improve stability, set this as high as you can without noticeable overlapping. It defaults to 0.1. """) def _set_collision_bias(self, collision_bias): cp.cpSpaceSetCollisionBias(self._space, collision_bias) def _get_collision_bias(self): return cp.cpSpaceGetCollisionBias(self._space) collision_bias = property(_get_collision_bias , _set_collision_bias , doc="""Determines how fast overlapping shapes are pushed apart. Pymunk allows fast moving objects to overlap, then fixes the overlap over time. Overlapping objects are unavoidable even if swept collisions are supported, and this is an efficient and stable way to deal with overlapping objects. The bias value controls what percentage of overlap remains unfixed after a second and defaults to ~0.2%. Valid values are in the range from 0 to 1, but using 0 is not recommended for stability reasons. The default value is calculated as cpfpow(1.0f - 0.1f, 60.0f) meaning that pymunk attempts to correct 10% of error ever 1/60th of a second. ..Note:: Very very few games will need to change this value. """) def _set_collision_persistence(self, collision_persistence): cp.cpSpaceSetCollisionPersistence(self._space, collision_persistence) def _get_collision_persistence(self): return cp.cpSpaceGetCollisionPersistence(self._space) collision_persistence = property(_get_collision_persistence , _set_collision_persistence , doc="""The number of frames the space keeps collision solutions around for. Helps prevent jittering contacts from getting worse. This defaults to 3. ..Note:: Very very few games will need to change this value. """) def _get_current_time_step(self): return cp.cpSpaceGetCurrentTimeStep(self._space) current_time_step = property(_get_current_time_step, doc="""Retrieves the current (if you are in a callback from Space.step()) or most recent (outside of a Space.step() call) timestep. """)
[docs] def add(self, *objs): """Add one or many shapes, bodies or joints to the space Unlike Chipmunk and earlier versions of pymunk its now allowed to add objects even from a callback during the simulation step. However, the add will not be performed until the end of the step. """ if self._in_step: self._add_later.update(objs) return for o in objs: if isinstance(o, Body): self._add_body(o) elif isinstance(o, Shape): self._add_shape(o) elif isinstance(o, Constraint): self._add_constraint(o) else: for oo in o: self.add(oo)
[docs] def remove(self, *objs): """Remove one or many shapes, bodies or constraints from the space Unlike Chipmunk and earlier versions of Pymunk its now allowed to remove objects even from a callback during the simulation step. However, the removal will not be performed until the end of the step. .. Note:: When removing objects from the space, make sure you remove any other objects that reference it. For instance, when you remove a body, remove the joints and shapes attached to it. """ if self._in_step: self._remove_later.update(objs) return for o in objs: if isinstance(o, Body): self._remove_body(o) elif isinstance(o, Shape): self._remove_shape(o) elif isinstance(o, Constraint): self._remove_constraint(o) else: for oo in o: self.remove(oo)
def _add_shape(self, shape): """Adds a shape to the space""" assert shape._get_shapeid() not in self._shapes, "shape already added to space" shape._space = weakref.proxy(self) self._shapes[shape._get_shapeid()] = shape cp.cpSpaceAddShape(self._space, shape._shape) def _add_body(self, body): """Adds a body to the space""" assert body not in self._bodies, "body already added to space" body._space = weakref.proxy(self) self._bodies.add(body) cp.cpSpaceAddBody(self._space, body._body) def _add_constraint(self, constraint): """Adds a constraint to the space""" assert constraint not in self._constraints, "constraint already added to space" self._constraints.add(constraint) cp.cpSpaceAddConstraint(self._space, constraint._constraint) def _remove_shape(self, shape): """Removes a shape from the space""" self._removed_shapes[shape._get_shapeid()] = shape del self._shapes[shape._get_shapeid()] cp.cpSpaceRemoveShape(self._space, shape._shape) def _remove_body(self, body): """Removes a body from the space""" body._space = None self._bodies.remove(body) cp.cpSpaceRemoveBody(self._space, body._body) def _remove_constraint(self, constraint): """Removes a constraint from the space""" self._constraints.remove(constraint) cp.cpSpaceRemoveConstraint(self._space, constraint._constraint)
[docs] def reindex_shape(self, shape): """Update the collision detection data for a specific shape in the space. """ cp.cpSpaceReindexShape(self._space, shape._shape)
[docs] def reindex_shapes_for_body(self, body): """Reindex all the shapes for a certain body.""" cp.cpSpaceReindexShapesForBody(self._space, body._body)
[docs] def reindex_static(self): """Update the collision detection info for the static shapes in the space. You only need to call this if you move one of the static shapes. """ cp.cpSpaceReindexStatic(self._space)
def _get_threads(self): if self.threaded: return int(cp.cpHastySpaceGetThreads(self._space)) return 1 def _set_threads(self, n): if self.threaded: cp.cpHastySpaceSetThreads(self._space, n) threads=property(_get_threads, _set_threads, doc="""The number of threads to use for running the step function. Only valid when the Space was created with threaded=True. Currently the max limit is 2, setting a higher value wont have any effect. The default is 1 regardless if the Space was created with threaded=True, to keep determinism in the simulation. """)
[docs] def step(self, dt): """Update the space for the given time step. Using a fixed time step is highly recommended. Doing so will increase the efficiency of the contact persistence, requiring an order of magnitude fewer iterations to resolve the collisions in the usual case. It is not the same to call step 10 times with a dt of 0.1 and calling it 100 times with a dt of 0.01 even if the end result is that the simulation moved forward 100 units. Performing multiple calls with a smaller dt creates a more stable and accurate simulation. Therefor it sometimes make sense to have a little for loop around the step call, like in this example: >>> import pymunk >>> s = pymunk.Space() >>> steps = 10 >>> for x in range(steps): # move simulation forward 0.1 seconds: ... s.step(0.1 / steps) :param float dt: Time step length """ self._in_step = True if self.threaded: cp.cpHastySpaceStep(self._space, dt) else: cp.cpSpaceStep(self._space, dt) self._removed_shapes = {} self._in_step = False for objs in self._add_later: self.add(objs) self._add_later.clear() for objs in self._remove_later: self.remove(objs) self._remove_later.clear() for key in self._post_step_callbacks: self._post_step_callbacks[key](self) self._post_step_callbacks = {}
[docs] def add_collision_handler(self, collision_type_a, collision_type_b): """Return the :py:class:`CollisionHandler` for collisions between objects of type collision_type_a and collision_type_b. Fill the desired collision callback functions, for details see the :py:class:`CollisionHandler` object. Whenever shapes with collision types (:py:attr:`Shape.collision_type`) a and b collide, this handler will be used to process the collision events. When a new collision handler is created, the callbacks will all be set to builtin callbacks that perform the default behavior (call the wildcard handlers, and accept all collisions). :param int collision_type_a: Collision type a :param int collision_type_b: Collision type b :rtype: :py:class:`CollisionHandler` """ key = (collision_type_a, collision_type_b) if key in self._handlers: return self._handlers[key] h = cp.cpSpaceAddCollisionHandler(self._space, collision_type_a, collision_type_b) ch = CollisionHandler(h, self) self._handlers[key] = ch return ch
[docs] def add_wildcard_collision_handler(self, collision_type_a): """Add a wildcard collision handler for given collision type. This handler will be used any time an object with this type collides with another object, regardless of its type. A good example is a projectile that should be destroyed the first time it hits anything. There may be a specific collision handler and two wildcard handlers. It's up to the specific handler to decide if and when to call the wildcard handlers and what to do with their return values. (See Arbiter.call_wildcard*()) When a new wildcard handler is created, the callbacks will all be set to builtin callbacks that perform the default behavior. (accept all collisions in :py:func:`~CollisionHandler.begin` and :py:func:`~CollisionHandler.pre_solve`, or do nothing for :py:func:`~CollisionHandler.post_solve` and :py:func:`~CollisionHandler.separate`. :param int collision_type_a: Collision type :rtype: :py:class:`CollisionHandler` """ if collision_type_a in self._handlers: return self._handlers[collision_type_a] h = cp.cpSpaceAddWildcardHandler(self._space, collision_type_a) ch = CollisionHandler(h, self) self._handlers[collision_type_a] = ch return ch
[docs] def add_default_collision_handler(self): """Return a reference to the default collision handler or that is used to process all collisions that don't have a more specific handler. The default behavior for each of the callbacks is to call the wildcard handlers, ANDing their return values together if applicable. """ if None in self._handlers: return self._handlers[None] _h = cp.cpSpaceAddDefaultCollisionHandler(self._space) h = CollisionHandler(_h, self) self._handlers[None] = h return h
[docs] def add_post_step_callback(self, callback_function, key, *args, **kwargs): """Add a function to be called last in the next simulation step. Post step callbacks are registered as a function and an object used as a key. You can only register one post step callback per object. This function was more useful with earlier versions of pymunk where you weren't allowed to use the add and remove methods on the space during a simulation step. But this function is still available for other uses and to keep backwards compatibility. .. Note:: If you remove a shape from the callback it will trigger the collision handler for the 'separate' event if it the shape was touching when removed. .. Note:: Post step callbacks are not included in pickle / copy of the space. :param callback_function: The callback function :type callback_function: `func(space : Space, key, *args, **kwargs)` :param Any key: This object is used as a key, you can only have one callback for a single object. It is passed on to the callback function. :param args: Optional parameters passed to the callback :param kwargs: Optional keyword parameters passed on to the callback :return: True if key was not previously added, False otherwise """ if key in self._post_step_callbacks: return False def f(x): callback_function(self, key, *args, **kwargs) self._post_step_callbacks[key] = f return True
[docs] def point_query(self, point, max_distance, shape_filter): """Query space at point for shapes within the given distance range. The filter is applied to the query and follows the same rules as the collision detection. If a maxDistance of 0.0 is used, the point must lie inside a shape. Negative max_distance is also allowed meaning that the point must be a under a certain depth within a shape to be considered a match. See :py:class:`ShapeFilter` for details about how the shape_filter parameter can be used. .. Note:: Sensor shapes are included in the result (In :py:meth:`Space.point_query_nearest` they are not) :param point: Where to check for collision in the Space :type point: :py:class:`~vec2d.Vec2d` or (float,float) :param float max_distance: Match only within this distance :param ShapeFilter shape_filter: Only pick shapes matching the filter :rtype: [:py:class:`PointQueryInfo`] """ self.__query_hits = [] @ffi.callback("cpSpacePointQueryFunc") def cf(_shape, point, distance, gradient, data): # space = ffi.from_handle(data) shape = self._get_shape(_shape) p = PointQueryInfo( shape, Vec2d._fromcffi(point), distance, Vec2d._fromcffi(gradient)) self.__query_hits.append(p) data = ffi.new_handle(self) cp.cpSpacePointQuery( self._space, tuple(point), max_distance, shape_filter, cf, data) return self.__query_hits
def _get_shape(self, _shape): if not bool(_shape): return None shapeid = cp.cpShapeGetUserData(_shape) #return self._shapes[hashid_private] if shapeid in self._shapes: shape = self._shapes[shapeid] elif shapeid in self._removed_shapes: shape = self._removed_shapes[shapeid] else: shape = None return shape
[docs] def point_query_nearest(self, point, max_distance, shape_filter): """Query space at point the nearest shape within the given distance range. The filter is applied to the query and follows the same rules as the collision detection. If a maxDistance of 0.0 is used, the point must lie inside a shape. Negative max_distance is also allowed meaning that the point must be a under a certain depth within a shape to be considered a match. See :py:class:`ShapeFilter` for details about how the shape_filter parameter can be used. .. Note:: Sensor shapes are not included in the result (In :py:meth:`Space.point_query` they are) :param point: Where to check for collision in the Space :type point: :py:class:`~vec2d.Vec2d` or (float,float) :param float max_distance: Match only within this distance :param ShapeFilter shape_filter: Only pick shapes matching the filter :rtype: :py:class:`PointQueryInfo` or None """ info = ffi.new("cpPointQueryInfo *") _shape = cp.cpSpacePointQueryNearest( self._space, tuple(point), max_distance, shape_filter, info) shape = self._get_shape(_shape) if shape != None: return PointQueryInfo( shape, Vec2d._fromcffi(info.point), info.distance, Vec2d._fromcffi(info.gradient)) return None
[docs] def segment_query(self, start, end, radius, shape_filter): """Query space along the line segment from start to end with the given radius. The filter is applied to the query and follows the same rules as the collision detection. See :py:class:`ShapeFilter` for details about how the shape_filter parameter can be used. .. Note:: Sensor shapes are included in the result (In :py:meth:`Space.segment_query_first` they are not) :param start: Starting point :param end: End point :param float radius: Radius :param ShapeFilter shape_filter: Shape filter :rtype: [:py:class:`SegmentQueryInfo`] """ self.__query_hits = [] @ffi.callback("cpSpaceSegmentQueryFunc") def cf(_shape, point, normal, alpha, data): shape = self._get_shape(_shape) p = SegmentQueryInfo( shape, Vec2d._fromcffi(point), Vec2d._fromcffi(normal), alpha) self.__query_hits.append(p) data = ffi.new_handle(self) cp.cpSpaceSegmentQuery( self._space, tuple(start), tuple(end), radius, shape_filter, cf, data) return self.__query_hits
[docs] def segment_query_first(self, start, end, radius, shape_filter): """Query space along the line segment from start to end with the given radius. The filter is applied to the query and follows the same rules as the collision detection. .. Note:: Sensor shapes are not included in the result (In :py:meth:`Space.segment_query` they are) See :py:class:`ShapeFilter` for details about how the shape_filter parameter can be used. :rtype: :py:class:`SegmentQueryInfo` or None """ info = ffi.new("cpSegmentQueryInfo *") _shape = cp.cpSpaceSegmentQueryFirst( self._space, tuple(start), tuple(end), radius, shape_filter, info) shape = self._get_shape(_shape) if shape != None: return SegmentQueryInfo( shape, Vec2d._fromcffi(info.point), Vec2d._fromcffi(info.normal), info.alpha) return None
[docs] def bb_query(self, bb, shape_filter): """Query space to find all shapes near bb. The filter is applied to the query and follows the same rules as the collision detection. .. Note:: Sensor shapes are included in the result :param BB bb: Bounding box :param ShapeFilter shape_filter: Shape filter :rtype: [:py:class:`Shape`] """ self.__query_hits = [] @ffi.callback("cpSpaceBBQueryFunc") def cf(_shape, data): shape = self._get_shape(_shape) self.__query_hits.append(shape) data = ffi.new_handle(self) cp.cpSpaceBBQuery(self._space, bb._bb, shape_filter, cf, data) return self.__query_hits
[docs] def shape_query(self, shape): """Query a space for any shapes overlapping the given shape .. Note:: Sensor shapes are included in the result :param shape: Shape to query with :type shape: :py:class:`Circle`, :py:class:`Poly` or :py:class:`Segment` :rtype: [:py:class:`ShapeQueryInfo`] """ self.__query_hits = [] @ffi.callback("cpSpaceShapeQueryFunc") def cf(_shape, _points, _data): shape = self._get_shape(_shape) point_set = ContactPointSet._from_cp(_points) info = ShapeQueryInfo(shape, point_set) self.__query_hits.append(info) data = ffi.new_handle(self) cp.cpSpaceShapeQuery(self._space, shape._shape, cf, data) return self.__query_hits
[docs] def debug_draw(self, options): """Debug draw the current state of the space using the supplied drawing options. If you use a graphics backend that is already supported, such as pygame and pyglet, you can use the predefined options in their x_util modules, for example :py:class:`pygame_util.DrawOptions`. Its also possible to write your own graphics backend, see :py:class:`SpaceDebugDrawOptions`. If you require any advanced or optimized drawing its probably best to not use this funtion for the drawing since its meant for debugging and quick scripting. :type options: :py:class:`SpaceDebugDrawOptions` """ h = ffi.new_handle(self) # we need to hold h until the end of cpSpaceDebugDraw to prevent GC options._options.data = h with options: cp.cpSpaceDebugDraw(self._space, options._options)
def __getstate__(self): """Return the state of this object This method allows the usage of the :mod:`copy` and :mod:`pickle` modules with this class. """ d = super(Space, self).__getstate__() d['special'].append(('shapes', self.shapes)) d['special'].append(('bodies', self.bodies)) d['special'].append(('constraints', self.constraints)) if self._static_body != None: d['special'].append(('_static_body', self._static_body)) handlers = [] for k,v in self._handlers.items(): h = {} if v._begin_base != None: h['_begin_base'] = v._begin_base if v._pre_solve_base != None: h['_pre_solve_base'] = v._pre_solve_base if v._post_solve_base != None: h['_post_solve_base'] = v._post_solve_base if v._separate_base != None: h['_separate_base'] = v._separate_base handlers.append((k,h)) d['special'].append(('_handlers', handlers)) return d def __setstate__(self, state): """Unpack this object from a saved state. This method allows the usage of the :mod:`copy` and :mod:`pickle` modules with this class. """ super(Space, self).__setstate__(state) for k,v in state['special']: if k == 'shapes': self.add(*v) if k == 'bodies': self.add(*v) if k == 'constraints': self.add(*v) if k == '_static_body': self._static_body = v self._static_body._space = self if k == '_handlers': for k, hd in v: if k == None: h = self.add_default_collision_handler() elif isinstance(k,tuple): h = self.add_collision_handler(k[0], k[1]) else: h = self.add_wildcard_collision_handler(k) if '_begin_base' in hd: h.begin = hd['_begin_base'] if '_pre_solve_base' in hd: h.pre_solve = hd['_pre_solve_base'] if '_post_solve_base' in hd: h.post_solve = hd['_post_solve_base'] if '_separate_base' in hd: h.separate = hd['_separate_base']
[docs] def copy(self): """Create a deep copy of this space.""" return copy.deepcopy(self)