Contents:

Shape¶

class pecrs.shape.Shape(x, y)¶

Parameters

x (Int) – Position of the shape in the x-axis
y (Int) – Position of the shape in the y-axis

Abstract Base Shape that other shapes extend from. Shapes are simple data structures that describe the physical properties of an body to a Collider.

position¶: Tuple(Int, Int), position of the shape

area¶: Tuple(Int, Int) or None, collision area of the shape

class pecrs.shape.Rect(x, y, width, height)¶

Parameters

x (Int) – Position of the shape in the x-axis
y (Int) – Position of the shape in the y-axis
width (int) – Width of the Rect
height (int) – Height of the Rect

A Rectangle Treated as Axis-Aligned Bounding Boxes by the Collider.

position¶: Tuple(Int, Int), position of the shape

width¶: Int, Width, extending up

height¶: Int, Height, extending to the right

class pecrs.shape.Circle(x, y, radius)¶

Parameters

x (Int) – Position of the shape in the x-axis
y (Int) – Position of the shape in the y-axis
radius (int) – Width of the Rect

A Circle

position¶: Tuple(Int, Int), position of the shape

radius¶: Int, Radius, extending from the center.

Collider¶

class pecrs.collider.Collider¶

Collider handles collisions between two objects with physical dimensions. Note that the collider is abstract and low-level, dealing with any set of positions and dimensions.

check(shape, other)¶

Parameters

shape (Shape) – Shape of the first object
other (Shape) – Shape of the second object

Returns

True if there is a collision, False is not

Return type

bool

Checks for a collision between any two shapes. Determines what the shapes are and sends them to the appropriate collision method. If you already know the shape of your objects, use a more direct method.

check_rects(shape, other)¶

Parameters

shape (Rect) – Shape of the first Rect
other (Rect) – Shape of the second Rect

Returns

True if there is a collision, False is not

Return type

bool

Checks for a collision between any two Rects. This is a higher level interface for Collider.rect_rect(). Note that Pyglet sprites are effectively Rects and can be used interchangably here.

check_circles(shape, other)¶

Parameters

shape (Circle) – Shape of the first Circle
other (Circle) – Shape of the second Circle

Returns

True if there is a collision, False is not

Return type

bool

Checks for a collision between any two Circles. This is a higher level interface for Collider.circle_circle().

rect_rect(w, h, x, y, wo, ho, xo, yo)¶

Parameters

w (Int) – Width of the first Rect
h (Int) – Height of the first Rect
x (Int) – x position of the first Rect
y (Int) – y position of the first Rect
wo (Int) – Width of the second Rect
ho (Int) – Height of the second Rect
xo (Int) – x position of the second Rect
yo (Int) – y position of the second Rect

Checks for a collision between two Rects in abstract.

rect_circle(w, h, x, y, ro, xo, yo)¶

Parameters

w (Int) – Width of the first Rect
h (Int) – Height of the first Rect
x (Int) – x position of the first Rect
y (Int) – y position of the first Rect
ro (Int) – Radius of the second Circle
xo (Int) – x position of the second Circle
yo (Int) – y position of the second Circle

Checks for a collision between a Rect and a Circle in abstract.

circle_rect(r, x, y, wo, ho, xo, yo)¶

Parameters

r (Int) – Radius of the first Circle
x (Int) – x position of the first Circle
y (Int) – y position of the first Circle
wo (Int) – Width of the second Rect
ho (Int) – Height of the second Rect
xo (Int) – x position of the second Rect
yo (Int) – y position of the second Rect

Checks for a collision between a Circle and a Rect in abstract. Interface for Collider.rect_circle

circle_circle(r, x, y, ro, xo, yo)¶

Parameters

r (Int) – Radius of the first Circle
x (Int) – x position of the first Circle
y (Int) – y position of the first Circle
ro – Radius of the second Circle
xo (Int) – x position of the second Circle
yo (Int) – y position of the second Circle

Checks for a collision between any two Circles abstract.

Space¶

class pecrs.space.Space(size=256)¶

Parameters: size (int) – Size of the collision areas

Space handles the movement and collision detection between shapes. You can change the values here to work with different spatial partioning system and collision systems.

grid¶: SpatialHash, spatial partitioning system. Think about combining these into one class

collider¶: Collider, collision detection system

add(shape, update_area=True)¶

Parameters: shape (Shape) – Shape to add to the space

Adds a shape to the space. Bodies are added to their collision area as well as the 8 nearest neighboring cells to handle overlap and fast moving obejcts.

delete(shape)¶

Parameters: shape (Shape) – Shape to removed from the space

Removes a shape from the space.

has(shape)¶

Parameters: shape (Shape) – Shape to check for
Returns: True if the space contains the shape, False if not
Return type: bool

Checks if a space has a shape in that shape’s area Note that the shape’s must be set correctly or errors can occur

collisions_at(x, y, width=1, height=1)¶

Parameters

x (Int) – Posistion to search for on the x-axis
y (Int) – Posistion to search for on the y-axis
width (Int) – Width of the search area
height (Int) – Height of the search area

Returns

List of shapes colliding at the position

Return type

list(Shapes)

Gets a list of all shapes colliding at x, y

collisions_with(shape)¶

Parameters: shape (Shape) – Shape to find collisions with
Returns: List of shapes colliding at the position
Return type: list(Shape)

Get a list of all shapes colliding with shape

check_at(x, y, width=1, height=1)¶

Parameters

x (Int) – Posistion to search for on the x-axis
y (Int) – Posistion to search for on the y-axis
width (Int) – Width of the search area
height (Int) – Height of the search area

Returns

True if there is a collision at x, y, False if not

Return type

bool

Check to see if there is a collision at x, y in space.

check(shape)¶

Parameters: shape (Shape) – Shape to check for collisions
Returns: True if the shape is colliding with anything in space, False if not
Return type: bool

Check to see if something is colliding with shape in the space.

check_two(shape, other)¶

Parameters

shape (Shape) – First Shape to check for collision
other (Shape) – Second Shape to check for collision

Returns

True if the two shapes are colliding, False if not

Return type

Bool

Check to see if two shapes are colliding

update_area(shape)¶

Parameters

shape (AbsBody) – Body to be moved from the space
area (Tuple(Int, Int)) – Area of the space to move the shape to

Returns

Original area if updating, None if not

Return type

Tuple(Int, Int) or None

Moves a shape from one collision area to another

move(shape, x, y, distance)¶

Parameters

shape (Shape) – Shape to move
x (int) – Direction to move in on horizontal plane
y (iny) – Direction to move in on the vertical plane
distance (float) – Distance to move for

Returns

Distance moved

Return type

tuple(int, int)

Advances a shape in the direction x, y for distance units.

push(shape, x, y)¶

Parameters

shape (Shape) – Shape to push
x (int) – Direction on the horizontal plane to push the shape
y (int) – Direction on the vertical plane to push the shape

Pushes a shape in the direction of x, y in space

place(shape, x, y)¶

Parameters

x (int) – The position in space to place the shape on the horizontal plane
y (int) – The position in space to place the shape on the vertical plane

Directly places a shape at x, y in space

Body¶

class pecrs.body.Body(id, x, y, width, height)¶

Parameters

id – Identifer of the body, should be unique to an Index
x (Int) – Position of the Body on the x-axis
y (Int) – Position of the Body on the y-axis
width (Int) – Width of the Body
height (Int) – Height of the Body

The abstract base class for all bodies. Bodies are physical entities that can interact with other bodies in space.

id¶: Identifer of the body, should be unique

direction¶: Tuple(int, int), holds the direction the body moves in

speed¶: Number, how fast the body moves

name¶: string, used to communicate body type in a reader friendly way

moving¶: bool, If the body should be moved during processing

Controller¶

class pecrs.controller.Controller(size=256)¶

Parameters: size (int) – Size of each collision area, in pixels. A large area means less area changes while moving but more collision checks

High-level manager of the physics system.

index¶: Index, Indexing system used to track bodies.

actives¶: list, stores Body for processing.

space¶: Space partionining system.

make(kind, x, y, width, height, id=None, dx=0, dy=0, static=False)¶

Parameters

kind (Uninstanced Body) – Class to be created
x (int) – Position in space to create the body on the horizontal plane
y (int) – Position in space to create the body on the vertical plane
width (int) – Width of the new body
height (int) – Height of the new body
id (int) – Unique identifer to assign to the body, generated by Index if None
dx (int) – Directional facing of the body
dy (int) – Directional facing of the body

Returns

Newly created body

Return type

kind

Creates a Body at position x, y with a height and width, then add it to the system.

on_make(body)¶

Parameters: body (Body) – Body that was made by the system

Callback when bodies are made by the system. Override this when extending your Controller.

add(body, id=None, static=False)¶

Parameters

body (Body) – Body to be added to the system
id (Int) – Unique identifer to assign to the body, generated by Index if None
static (Bool) – If the Body is Static or Dynamic

Adds a body to the system and space.

delete(body)¶

Parameters: body (Body) – Body to be removed from the system

Removes a body from the system. Triggers on_delete(body) callback

delete_id(id)¶

Parameters: id (int) – id of the body to be removed from the system

Removes a body from the system by id. Triggers on_delete(body) callback

on_delete(body)¶

Parameters: body (Body) – Body removed from the system

Callback when bodies are deleted by the system. Override this when extending your Controller

move(body, delta)¶

Parameters

body (Body) – Body to be moved by the system
delta (float) – Units of time to move the body

Move a body by it’s speed and direction for delta. Triggers the on_move(body, distance) and on_motion(body) callbacks

move_to(body, x, y, delta)¶

Parameters

body (Body) – Body to be moved by the system
x (int) – Direction to move the body in on the horitzontal plane
y (int) – Direction to move the body in on the vertical plane
delta (float) – Units of time to advance the simulation by

Move a body by it’s speed in the direction of x, y for delta. Triggers the on_move(body, distance) and on_motion(body) callbacks

on_move(body, distance)¶

Parameters

body (Body) – Body that was moved by the system
distance (tuple(int, int)) – The distance moved by the body

Callback when bodies are moved by the system. Override this when extending your Controller

push(body, x, y)¶

Parameters

body (Body) – Body to be pushed by the system
x (int) – Direction to push the body in on the horitzontal plane
y (int) – Direction to push the body in on the vertical plane

Pushes a body in the direction of x, y. Triggers callbacks for on_push(body, x, y) and on_motion(body)

on_push(body, x, y)¶

Parameters

body (Body) – Body that was pushed in space by the system
x (int) – Direction the body was pushed in on the horitzontal plane
y (int) – Direction the body was pushed in on the vertical plane

Callback when bodies are pushed by the system. Override this when extending your Controller

place(body, x, y)¶

Parameters

body (Body) – Body to be placed in space by the system
x (int) – Position to place the body in on horitzontal plane
y (int) – Position to place the body in on the vertical plane

Directly place a body at x, y Triggers the callbacks on_place(body, start) and on_motion(body) Use this instead of body.place(x, y) to keep track of collision area

on_place(body, start)¶

Parameters

body (Body) – Body that was placed by the system
start (Tuple(Int, Int)) – The location of the body before being placed

Callback triggered when bodies are placed by the system. Override this when extending your Controller

on_motion(body)¶

Parameters: body (Body) – Body that had its position changed by the system.

Callback when bodies change positions. This is triggered by both move and place. Override this when extending your Controller

on_area(body, start)¶

Parameters

body (Body) – Body that had its area changed by the system.
start (Tuple(Int, Int)) – Area the Body was in before it was changed.

Callback when bodies change collision areas. This is triggered by move(), move_to(), place(), and push(). Override this when extending your Controller.

turn(body, x, y)¶

Parameters

body (Body()) – Body to be rotated from the system
x (int) – Direction to move to in the horitzontal plane
y (int) – Direction to move to in the vertical plane

Change the direction of a body

on_turn(body)¶

Parameters: body (Body()) – Body that was turned

Callback when a body is turned by the system. Override this when extending your Controller

start_moving(body)¶

Parameters: body (Body()) – Body to active for movement during processing by the system

Tells a body to move when the system is processed.

on_start_moving(body)¶

Parameters: body (Body()) – Body that was actived for movement

Callback when bodies are told to move by the system. Override this when extending your Controller

stop_moving(body)¶

Parameters: body (Body()) – Body to deactived system movement processing for

Tells a body to not move when the system is proccessed.

on_stop_moving(body)¶

Parameters: body (Body()) – Body that was deactived for movement

Callback when bodies are told to stop by the system. Override this when extending your Controller

get(id)¶

Parameters: id (int) – id of the body to get
Returns: Body or None
Return type: Body or None

Gets an body by its id.

collisions_at(x, y, width=1, height=1)¶

Parameters

x (int) – Position to seach for on in the horitzontal plane
y (int) – Position to seach for on in the vertical plane

Returns

A list of bodies located at x, y

Return type

List(Body)

Finds all of the bodies at x, y.

collisions_with(body)¶

Parameters: body (Body) – Body to check for collisions
Returns: A list of bodies colliding with body
Return type: List(Body)

Finds all bodies colliding with body.

check(body)¶

Parameters: body (Body) – Body to check for collisions with
Returns: True if Collisions, False is not
Return type: Bool

Check to see if any shapes are colliding with the Body in space

check_at(x, y, width=1, height=1)¶

Parameters

x (Int) – Posistion to search for on the x-axis
y (Int) – Posistion to search for on the y-axis
width (Int) – Width of the search area
height (Int) – Height of the search area

Returns

True if there is a collision at x, y, False if not

Return type

bool

Check to see if there is a collision at x, y in space.

check_two(body, other)¶

Parameters

body (Body) – First Body to check for collision
other (Body) – Second Body to check for collision

Returns

True if the two bodies are colliding, False is not

Return type

Bool

Check to see if the two bodies are colliding.

step(delta)¶

Parameters: delta (float) – Units of time to advance the simulation

Process the system for delta steps. Triggers the on_step_start(delta), on_step(body, delta), on_collision(body, collisions), and on_step_end(delta) callbacks

on_step_start(delta)¶

Parameters: delta (float) – Units of time to advance the simulation

Callback before the simulation takes a step. Override this when extending your Controller

on_step(body, delta)¶

Parameters

body (Body) – Body being processed by the step
delta (float) – Units of time to advance the simulation

Callback when the simulation takes a step over a body. Override this when extending your Controller

on_collision(body, collisions)¶

Parameters

body (Body) – Body involved in a collision
collision – List of bodies colliding with body

Callback when bodies collide with another body. Override this when extending your Controller

on_step_end(delta)¶

Parameters: delta (float) – Units of time to advance the simulation

Callback after the simulation takes a step. Override this when extending your Controller

Spatialhash¶

class pecrs.spatialhash.SpatialHash(size)¶

Parameters: size (int) – Size of each grid cell

A generic spatialhash Keeps a bucket of objects at a given scaled position

grid¶: dict, Grid of buckets

size¶: int, Size of each grid cell

scale(x, y)¶

Parameters

x (int) – A position in to be scaled on the horizontal plane
y (int) – A position in to be scaled on the horizontal plane

Returns

Grid cell key for the position at x, y

Return type

tuple(int, int)

Scales an x, y value to a grid cell position

add(item, area)¶

Parameters

item (Object) – Item to be added to the grid
area (tuple(int, int)) – Area to add the item to

Add an item to the grid at an area

add_pos(item, x, y)¶

Parameters

item (Object) – Item to be added to the grid
x (int) – Area position
y (int) – Area position

Add an item to the grid at x, y

has(item, area=None)¶

Parameters

item (Object) – Item to be added to the grid
area (tuple(int, int) or None) – Area to check, checks all if None

Checks to see if an item is in the grid

get(area)¶

Parameters: area (tuple(int, int)) – Grid area
Returns: List of objects at position at x, y
Return type: list(Object)

Get a bucket at area from the grid

get_pos(x, y)¶

Parameters

x (int) – Area position
y (int) – Area position

Returns

List of objects at position at x, y

Return type

list(Object)

Get a bucket at x, y from the grid

delete(item, area)¶

Parameters

item (Object) – Item to be removed to the grid
area (tuple(int, int)) – Area to remove the item from

Remove an item from the grid at an area

delete_pos(item, x, y)¶

Parameters

item (Object) – Item to be removed to the grid
x (int) – Area position
y (int) – Area position

Remove an item to the grid at x, y

Index¶

class pecrs.index.Index¶

Indexing system for assigning unique IDs to bodies.

Index keeps track what number to assign to new entities.

TODO move object list keeping and retrival; update docs

count¶: The ID to be used for the next new body

free¶: A list of free IDs for reuse

list¶: List of objects by thier id

next()¶

Returns: A unique id
Return type: int

Gets a unique identifer for this index. Freed ids are assigned first, in first-in-last-out order.

delete(id)¶

Parameters: id (int) – Previously assigned id to be returned to the system

Frees an identifer to be reused.

Clock¶

class pecrs.clock.Clock(rate)¶

Parameters: rate (float) – Minimum amount of time before the next tick can occur

Keeps track of time through polling tick

rate¶: float, Minimum amount of time before the next tick can occur

time¶: ctypes.c_ulong, Number of ticks. Using ctypes for free rollover

last¶: time.time, Time of the last tick

get_time()¶: Get the number of ticks that have elapsed :return: Number of ticks that have elapsed :rtype: int

tick()¶

Returns: delta or None
Return type: float or None

Attemps to advance the system clock. Delta is the ratio of time that has passed since the tick. For example if your tick rate is 100ms, and your tick happens 150ms after your last tick, your delta will be 1.5 You probably are going to want to use this one for timing in games

tick_time()¶

Returns: Current time
Return type: int

Attemps to advance the system clock. Always returns the time.

tick_check()¶

Returns: True if rate time has elapsed since the last tick, False if not
Return type: bool

Attemps to advance the system clock.

class pecrs.clock.SyncClock¶

A Clock for syncing values from a master Clock.

get_time()¶

Returns: The current time
Return type: int

Gets the current time

Shape¶

Collider¶

Space¶

Body¶

Controller¶

Spatialhash¶

Index¶

Clock¶

Indices and tables¶