miercuri, 27 ianuarie 2016

PyGame - effects - part 001.

Today I come one simple and nice tutorial about pygame python module over python version 3.4 .
The python script just make two effects. First is one fade effect from transparent to black.I also added one green color.
Another effect come with the dizzy star base math python module and random python module.
Because this combined colors grean and blue are funny I make star blue.
The script is simple :
  • created variables;
  • make pygame windows; 
  • make fade background function;
  • make one class for shape ( and this can be updated );
  • make loop the game and escape key option;
  •  ... and finally add shape class and variable into loop pygame script.
Let's see the script:
# Cătălin George Feștilă 
# http://free-tutorials.org

import pygame
import random
import math
from pygame.locals import *

#initialize pygame and random seed
pygame.init()
random.seed()

#transparent to black for fade effect
def background_fade():
    rec = pygame.Surface(screensize)
    if frame != 0:
        rec.set_alpha(10)
        rec.fill((0,0,0))
    else:
        rec.set_alpha(255)
        rec.fill(draw_color)
    screen.blit(rec,(0,0))
    del rec

#all mathmatical shapes
class shape():
    xy = [0,0]   #location
    rot = [0.0,0.0] #rotation
    color = '.'   #color/shape value
    dim_size = 1
 #constructor
    def __init__(self,xy,dim_size,color):
        self.xy = xy
        self.dim_size = dim_size
        
        self.rot = [(random.random()*(math.pi)),.002]
        self.color = color
 
 #define shape
    def set_shape(self,color):
        self.color = color
    
 #draw shape    
    def draw(self):
        #rotation
        self.rot[0] += self.rot[1]
        if self.rot[0] > math.pi*2:
            self.rot[0] -= math.pi*2
        #blue/star
        if self.color == 'blue':
            for x in range(5):
                pygame.draw.aaline(screen,(0,0,255),\
                        (((math.cos(self.rot[0]+(x*((math.pi*2)/5)))*self.dim_size)+self.xy[0]),\
                        ((math.sin(self.rot[0]+(x*((math.pi*2)/5)))*self.dim_size)+self.xy[1])),\
                        (((math.cos(self.rot[0]+((x+2)*((math.pi*2)/5)))*self.dim_size)+self.xy[0]),\
                        ((math.sin(self.rot[0]+((x+2)*((math.pi*2)/5)))*self.dim_size)+self.xy[1])),\
                        1)

#start main pygame effect
while 1:
    #create variable for pygame
    screensize = (640,480)
    screen = pygame.display.set_mode(screensize, 0, 32)
    clock = pygame.time.Clock()
    #set frame 
    frame = 0
    draw_color = [0,255,0]
    #reftime = pygame.time.get_ticks()
    text = pygame.font.Font(None,25)
    #start drawing
    while 1:
        clock.tick(30)
        shapetest=shape((320,240),100,'blue')
        shapetest.draw()
        #check if is pressed any key 
        pygame.event.get()
        #if is press escape key
        if pygame.key.get_pressed()[pygame.K_ESCAPE]:
            pygame.quit()
            exit()
        #print clock.get_fps() on windows title
        pygame.display.set_caption(str(clock.get_fps()))   
        pygame.display.update()
        #start fade background
        background_fade()
        #change var frame for background_fade
        frame += 1
        #stop when frame is 100
        if frame == 100:
         break

    frame = 0
    
    pygame.display.update()
    background_fade()

    frame += 1
I make one screenshot to see how it's working.