sep-pm-platformer/project/sprite/DynamicSprite.py

from typing import Optional

from physics.CollisionDirection import CollisionDirection
from sprite.Spritesheet import Spritesheet
from sprite.StaticSprite import StaticSprite
from physics.TickData import TickData


class DynamicSprite(StaticSprite):
    def __init__(self, spritesheet: Optional[Spritesheet] = None):
        super().__init__(spritesheet)

        self.motion = (0, 0)

        self.apply_base_deceleration = True
        self.deceleration_horizontal_air = 0.02
        self.deceleration_horizontal_ground = 0.3
        self.gravity = 9.81 / 10

    def tick(self, tick_data: TickData):
        super().tick(tick_data)

        if self.apply_base_deceleration:
            deceleration_horizontal = 0
            if abs(self.motion[0]) > 0:
                if self.get_collides_with_direction(CollisionDirection.BOTTOM):
                    deceleration_horizontal = self.deceleration_horizontal_ground
                else:
                    deceleration_horizontal = self.deceleration_horizontal_air

            self.motion = (
                self.motion[0] - deceleration_horizontal * self.motion[0] * tick_data.dt,
                self.motion[1] + self.gravity * tick_data.dt
            )