stacked_sprite.py

from settings import *
import math


class StackedSprite(pg.sprite.Sprite):
    def __init__(self, app, name, pos, rot=0, collision=True):
        self.app = app
        self.name = name
        self.pos = vec2(pos) * TILE_SIZE
        self.player = app.player
        self.group = app.main_group
        super().__init__(self.group)

        if collision:
            self.app.collision_group.add(self)

        self.attrs = STACKED_SPRITE_ATTRS[name]
        self.y_offset = vec2(0, self.attrs['y_offset'])
        self.cache = app.cache.stacked_sprite_cache
        self.viewing_angle = app.cache.viewing_angle
        self.rotated_sprites = self.cache[name]['rotated_sprites']
        self.collision_masks = self.cache[name]['collision_masks']

        self.angle = 0
        self.screen_pos = vec2(0)
        self.rot = (rot % 360) // self.viewing_angle

        self.image = self.rotated_sprites[self.angle]
        self.mask = self.collision_masks[self.angle]
        self.rect = self.image.get_rect()

    def change_layer(self):
        self.group.change_layer(self, self.screen_pos.y)

    def transform(self):
        pos = self.pos - self.player.offset
        pos = pos.rotate_rad(self.player.angle)
        self.screen_pos = pos + CENTER

    def get_angle(self):
        self.angle = -math.degrees(self.player.angle) // self.viewing_angle + self.rot
        self.angle = int(self.angle % NUM_ANGLES)

    def update(self):
        self.transform()
        self.get_angle()
        self.get_image()
        self.change_layer()

    def get_image(self):
        self.image = self.rotated_sprites[self.angle]
        self.mask = self.collision_masks[self.angle]
        self.rect = self.image.get_rect(center=self.screen_pos + self.y_offset)


class TrnspStackedSprite(StackedSprite):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.app.transparent_objects.append(self)

        self.alpha_trigger = False
        self.alpha_objects = self.cache[self.name]['alpha_sprites']
        self.dist_to_player = 0.0

    def get_dist_to_player(self):
        self.dist_to_player = self.screen_pos.distance_to(self.player.rect.center)

    def update(self):
        super().update()
        self.get_dist_to_player()

    def get_image(self):
        super().get_image()
        self.get_alpha_image()

    def get_alpha_image(self):
        if self.alpha_trigger:
            if self.rect.centery > self.player.rect.top:
                if self.rect.contains(self.player.rect):
                    self.image = self.alpha_objects[self.angle]
                    self.alpha_trigger = False