`pyxen.Camera`

A Camera defines what the renderer sees in the world.

It is attached to an entity as a component. The renderer uses the camera’s transform and properties to compute the view and projection matrices.

A world must contain at least one camera to render anything.

Creating a Camera

camera = world.spawn(
    x=0,
    y=0,
    camera=Camera()
)

Or added later:

camera = world.spawn()
camera.camera = Camera()

Camera Uses the Entity Transform

A camera does not store position itself — it uses the entity’s transform:

camera.x = 100
camera.y = 50
camera.rotation = 30
camera.scale = (2, 2)

Moving the entity moves the view. Parent transforms also affect the camera.

Properties

zoom

camera.camera.zoom = 1.0

Type: float Default: 1.0

Value	Effect
`1.0`	Default view
`>1`	Zoom in
`<1`	Zoom out

Example:

camera.camera.zoom = 2.0  # zoom in
camera.camera.zoom = 0.5  # zoom out

Zoom affects only the projection matrix, not the entity transform.

Example: Following a Player

player = world.spawn(x=0, y=0, sprite=hero)

camera = world.spawn(camera=Camera())

def update():
    camera.x = player.x
    camera.y = player.y

Or simpler, set the camera parent to the player:

player = world.spawn(x=0, y=0, sprite=hero)
camera = world.spawn(camera=Camera(), parent=player)

Zoomed-out camera:

camera.camera.zoom = 0.75

Screen Shake & Flash

A camera can apply two screen effects, both measured in frames (Pyxen runs at a fixed 30 fps):

cam = entity.camera

cam.shake(intensity, duration=8)   # jolt the view; fades out over `duration`
cam.flash(color, duration=8)       # full-screen colour that fades out

Method	Parameters	Description
`shake(intensity, duration=8)`	`intensity` in pixels, `duration` in frames	Jitters the view by a deterministic, decaying offset.
`flash(color, duration=8)`	`color` as a `Color` or `(r, g, b[, a])`, `duration` in frames	Fades a full-screen colour overlay out over `duration`.

def on_hit():
    entity.camera.shake(3.0, 10)
    entity.camera.flash((1.0, 0.0, 0.0, 0.6), 6)

Both effects are deterministic, so they replay identically in the time-travel debugger.

Multiple Cameras

If multiple cameras exist, the first active camera found in the world is used.

Mini samples

Open from Samples & Tutorials inside Pyxen:

Camera() follow — Camera attached to an entity follows it. Use arrow keys.
tween zoom — Animate the camera’s zoom factor.