Pygame sprite clamping isse - sprite

Question

So Ive been having issues with getting a sprite to stay withing the bounds of the screen. I got it to work with a simple rect(0,0,16,16), but i cant seem to get it to work with a sprite being blit onto the screen. What do i need to change in order to keep my sprite clamped within the screen res? I only just started today using classes to orgonize code so any input is appreciated and helpful.
import pygame
from pygame.locals import *
from pygame import Color
class Game():
""" Lets try to get this going by simple steps
One by one. First step, lets figure how to make a class
that can do the display stuff. Lord have mercy on my soul"""
def __init__(self, wi=256, hi=224, multii=3):
"""Initialization"""
pygame.init()
self.runGame = True
self.width = wi*multii
self.height = hi*multii
self.spritesize = 16*multii
self.clock = pygame.time.Clock()
self.fps = self.clock.get_fps()
self.screen = pygame.display.set_mode((self.width, self.height))
self.kl = []
self.walk = [0, 0]
self.speed = multii*1.5
self.x,self.y = self.width/2, self.height/2
self.playerSpr = pygame.image.load('images/'+'link1.png').convert_alpha()
self.playerRec = Rect(self.playerSpr.get_rect())
def mainLoop(self):
"""Loop through the main game routines
1. Drawing 2. Input handling 3. Updating
Then loop through it until user quits"""
while self.runGame:
self.clock.tick(60)
self.events()
self.draw()
def events(self):
"""Time to handle some events"""
for e in pygame.event.get():
if (e.type == pygame.QUIT) or (e.type == KEYDOWN and e.key == K_ESCAPE):
self.runGame = False
break
if e.type==KEYDOWN:
if e.key==pygame.K_a: self.kl.append(1)
if e.key==pygame.K_d: self.kl.append(2)
if e.key==pygame.K_w: self.kl.append(3)
if e.key==pygame.K_s: self.kl.append(4)
if e.type==pygame.KEYUP:
if e.key==pygame.K_a: self.kl.remove(1)
if e.key==pygame.K_d: self.kl.remove(2)
if e.key==pygame.K_w: self.kl.remove(3)
if e.key==pygame.K_s: self.kl.remove(4)
if self.kl[-1:]==[1]: self.walk=[-self.speed, 0]
elif self.kl[-1:]==[2]: self.walk=[ self.speed, 0]
elif self.kl[-1:]==[3]: self.walk=[0,-self.speed]
elif self.kl[-1:]==[4]: self.walk=[0, self.speed]
else: self.walk=[0, 0]
self.x+=self.walk[0]
self.y+=self.walk[1]
def draw(self):
"""Draw and update the main screen"""
self.fps = self.clock.get_fps()
self.screen.fill(Color('purple'))
#print self.screen.get_rect()
#print player_rect
self.playerSpr.clamp_ip(self.screen.get_rect())
#pygame.draw.rect(self.screen, (255, 255, 255), self.playerrect)
self.screen.blit(self.playerSpr, (self.x,self.y), self.playerRec)
pygame.display.set_caption('Grid2. FPS: '+str(self.fps))
pygame.display.update()
game = Game()
game.mainLoop()

Answer 1

Why not use playerRec to keep track of the position of your player instead of the additional x and y attributes?
I suggest also using the move method (or move_ip):
def events(self):
for e in pygame.event.get():
...
self.playerRec.move_ip(*self.walk) # instead of self.x+=self.walk[0] / self.y+=self.walk[1]
def draw(self):
...
# probably do this right after 'move_ip'
self.playerRec.clamp_ip(self.screen.get_rect())
# note that 'blit' accepts a 'Rect' as second parameter
self.screen.blit(self.playerSpr, self.playerRec)
as a side note: You should consider using a Sprite, since it basically combines an Image and a Rect.

Answer 2

Two things:
You are not stopping movement of the sprite when it comes off the screen.
Make an move functions that will get a direction and will decide if it can move more to the side. That way when the right side of the sprite will be of screen, you will not move more to the right.
Since you put your direction keys in a list that works like a stack, you are only getting 1 direction per keypress. If you also want to move diagonally either make two lists one for both directions or use a easier method such as this:
if KEYDOWN == K_LEFT: direction_x = -1
if KEYUP == K_LEFT AND direction_x == -1: direction_x = 0
do this for every key.