Moss/sprite_stacking_engine/stacked_sprite.py

#!/usr/bin/python3
import pygame

from settings import *
import math


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

        self.attrs = SPRITE_ATTRS[name]  # get attributes

        if not "scale" in self.attrs:
            self.attrs["scale"] = DEFAULT_SCALE

        self.y_offset = vec2(0, -self.attrs["layers"] / 2 * self.attrs["scale"])  # calculate the y offset because the -
        # images position in pygame is the position of the top left corner of the image and we use the bottom position
        self.cache = self.app.cache.stacked_sprite_cache
        self.viewing_angle = app.cache.viewing_angle
        self.rotated_sprites = self.cache[name]["rotated_sprites"]
        self.angle = 0
        self.screen_position = vec2(0)
        self.rot = (rot % 360) // self.viewing_angle

    def transform(self):  # recalculate position and rotation
        pos = self.pos - self.player.offset
        pos = pos.rotate_rad(self.player.angle)
        self.screen_position = pos + CENTER

    def change_layer(self):  # calculate the layer to draw over the things behind it and not the other way
        self.group.change_layer(self, self.screen_position.y)

    def get_angle(self):  # calculate the angle to draw the right sprite
        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.rect = self.image.get_rect(center=self.screen_position + self.y_offset)


class AnimatedStackedSprite(pygame.sprite.Sprite):  # stacked sprite class for animated sprites, works nearly the same
    def __init__(self, app, name, pos, rot=0):
        self.app = app
        self.name = name
        self.pos = vec2(pos) * TILE_SIZE
        self.player = self.app.player
        self.group = self.app.main_group
        super().__init__(self.group)

        self.attrs = ANIMATED_SPRITE_ATTRS[name]

        if not "scale" in self.attrs:
            self.attrs["scale"] = DEFAULT_SCALE

        self.attrs["animated"] = True  # set the animated attribute to true so that the cache knows that this sprite -
        self.y_offset = vec2(0, -self.attrs["layers"] / 2 * self.attrs["scale"])  # is animated
        self.cache = self.app.cache.stacked_sprite_cache
        self.viewing_angle = app.cache.viewing_angle
        self.frame = list(self.cache[name]["frames"].keys())[0]  # set the frame to the first frame
        self.rotated_sprites = self.cache[name]["frames"][self.frame]["rotated_sprites"]
        self.angle = 0
        self.screen_position = vec2(0)
        self.rot = (rot % 360) // self.viewing_angle

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

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

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

    def animate(self):  # change the layer to display another frame
        self.frame = str(round(self.app.time) * 4 % 3)
        self.rotated_sprites = self.cache[self.name]["frames"][self.frame]["rotated_sprites"]

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

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