I'm trying to make a function that fades OUT (increases the transparency of) a sprite overlay, a large color block that covers the screen. However, for some reason, only the fade-in function works as intended. The fade-out function immediately draws the sprite overlay at its max opacity (255), but doesn't show the desired fade-out effect in spite of using the same algorithm as the fade-in function does, though with different range values, of course.
EDIT:
Alright, I think I know the deal here.
The fade-out function draws the overlay over the background... and leaves it there as it keeps continuously drawing it over it like a moron.
I get it.
I'm gonna toy around with this.
Here are the two functions:
This one works:
def fade_in(self):
self.FaderInUse.add(self)
for x in range(0, 256, self.rate):
self.colorfade.set_alpha(x)
screen.blit( self.colorfade, ( 0, 0 ) )
pygame.display.flip()
clock.tick(15)
self.FaderInUse.clear( screen, screen )
DrawScreen()
This one, however, doesn't quite cut it:
def fade_out(self):
self.FaderInUse.add(self)
for x in range( 255, -1, ( self.rate * -1 ) ):
self.colorfade.set_alpha(x)
screen.blit( self.colorfade, ( 0, 0 ) )
pygame.display.flip()
clock.tick(15)
self.FaderInUse.clear( screen, screen )
DrawScreen()
Can You show how u created the self.colorfade object. And, did you use self.colorfade.convert_alpha() ? You have to use convert_alpha to be able to change the alpha value of the object.
Related
I'm making a Pong game in Actionscript 3 and I'm pretty much done it, however I need to create a feature where if the paddle passes the top of the screen it goes back to the bottom, and if it passes through the bottom it appears at the top. How would I create something like this?
Y axis is for up/down so use paddle.y to check the position...
Some logic like this :
if ( paddle.y <= (-paddle.height) )
{ paddle.y = ( stage.stageHeight - paddle.height ); }
Just an example you can test and refine. This assumes your paddle is on stage directly. If the paddle was instead added to some container (Sprite or MovieClip) then instead you use:
{ paddle.y = ( containerMC.height - paddle.height ); }
If you want an effect where, for example, the top-half of your paddle is above screen then there is a half-paddle at the bottom... for that you just use two instances (copies) of the paddle Sprite.
here is my code:
import pygame
import sys
pygame.init()
FPS=30
clock=pygame.time.Clock()
white=(255,255,255) #background
screen=pygame.display.set_mode((480,320)) #screen size
pygame.display.set_caption("Zombie Game!")
mainsheet=pygame.image.load("C:\Python34\MyMan.png") #load image
sheet_size=mainsheet.get_size() #get size of img
steps_right=8 #first 8 pictures is moving to the right
jump=16 #next 8 (actually 5) is jumping
steps_left=24 #next 8 is moving to the left
cell_width=int(sheet_size[0]/8) #width of the one animation
cell_height=int(sheet_size[1]/4) #height of the one animation
cell_list=[]
for y in range(0,sheet_size[1],int(cell_height)): #looping through image
for x in range(0,sheet_size[0],int(cell_width)):
surface=pygame.Surface((cell_width,cell_height))
surface.blit(mainsheet,(0,0),(x,y,cell_width,cell_height))
cell_list.append(surface) #adding images to list
cell_position=0
running=True
pygame.key.set_repeat(50, 50) #if they hold the key
while running:
for event in pygame.event.get():
if event.type==pygame.QUIT:
pygame.quit()
sys.exit()
if event.type==pygame.KEYDOWN:
if event.key==pygame.K_RIGHT: #if to the right..
if cell_position <steps_right-1:
cell_position+=1
else:
cell_position=0
if event.key==pygame.K_LEFT:
if cell_position<steps_left-1 and cell_position>jump:
cell_position+=1
else:
cell_position=jump+1
if event.key==pygame.K_UP:
if cell_position<12 and cell_position>7:
cell_position+=1
else:
cell_position=8
screen.fill(white)
screen.blit(cell_list[cell_position],(100,10))
clock.tick(FPS)
pygame.display.update()
I know that maybe it isn't the best way to do it but it's my first try. But there are 2 problems(at least): 1)"Character" is moving(animated) but of course he doesn't move and I dont have any idea how to do that ,if it was only simple rectangle then I would,but this is a little bit complicated ..and 2) when I try to change the background to white instead of black,my character is in the small black square but background is white..thanks for help!!!! :-))
Notes:
"C:\Python34\MyMan.png": please start this with r"" or use double slashes. Otherwise, if you put this in a directory starting with n or something, things will break.
Background color is caused (presumably) by using a non-transparent image. png supports transparency. I think there might be a flag to send to Pygame to mark it as transparent, but I don't remember what it is.
For movement, look at the line screen.blit(cell_list[cell_position],(100,10)). That's an xy coordinate pair; change those from constants to variables, and change them in the event loop.
I have lot of sprites on screen ( cars looking from top ) and I am drawing polylines ( like call ccDrawPoly(redBlue, 8, false) ). I need to replace line color with texture ( I have image of water and I want to draw line with water texture water.png ).
How to make this ?
PaolaJ, I could suggest a hack
Create Sprite Object
Give it some width like 2,4,8 or 16 (depending on your texture)
Sprite Height could be same as line length.
Use sprite->getTexture()->setTexParameters({GL_LINEAR, GL_LINEAR,GL_REPEAT,GL_REPEAT}) to repeat your texture.
use rotation to place the sprite properly.
make sure texture is power of 2.
On the other hand, proper way would be textured polygon as LearnCocos2d suggested.
Before I start, let me say that I'm a complete beginner at Pygame.
Here's my current program:
import pygame, sys, random
pygame.init()
white = ((255,255,255))
display_width = 800
display_height = 600
FPS = 15
gameDisplay = pygame.display.set_mode((display_width, display_height))
pygame.display.set_caption('Francis')
gameExit = False
lead_x = display_width/2
lead_y = display_height/2
lead_x_change = 0
lead_y_change = 0
clock = pygame.time.Clock()
while not gameExit:
for event in pygame.event.get():
if event.type== pygame.QUIT:
gameExit = True
francis = pygame.sprite.Sprite() #create sprite
francis.image = pygame.image.load("francis.png").convert() #load francis image
francis.rect = francis.image.get_rect() # use image extent values
francis.rect.center = [lead_x,lead_y]
gameDisplay.fill(white)
gameDisplay.blit(francis.image, francis.rect)
pygame.display.update()
clock.tick(FPS)
pygame.quit()
quit()
What I plan to do with this program is load in my sprite (francis) and use the arrow keys to move him across the screen. I plan to create that motion by having each arrow key pressed add or subtract 10 pixels from lead_x, which should be the sprite's x location. I'm not sure whether the code I used to load in the sprite is correct. I used "francis.rect.center" then gave the coordinates to that. Is there a better way to load and position a sprite?
Also, my sprite has a black rectangle around it whenever I load it. The sprite itself is a 30x70 picture. Where there is not a pixel of the actual person, I just have transparency. The transparency works fine, but whenever I load in the image, there's a black rectangle around the border of the sprite. I have a feeling this has to do with the way I loaded in the sprite, but I'd appreciate if you'd let me know. (I've tried converting it to png, bmp, and jpg. png and bmp both have black borders, and jpg has black background instead of transparency)
Any and all help is appreciated!
When you do your image load with
francis.image = pygame.image.load("francis.png").convert() #load francis image
you should do
francis.image = pygame.image.load("francis.png").convert_alpha() #load francis image
as png images have an alpha channel which is the transparent part of the image. If you don't know what this means load your image into an image editor and remove the part you do not need by selecting the and deleting them. Now these parts will contain no colour information and therefor will be the alpha channel for the image.
You can also set the colour key of the image by
francis.image.set_colorkey(0, RLEACCEL) # the colour key is set to 0
A key colour is also transparent. (That's how they shoot movies like spiderman, fantastic four etc. :-))
read this too
https://www.pygame.org/docs/ref/surface.html#pygame.Surface.set_alpha.
hope this helps.
Regarding how you position sprites, I believe the norm is to go by the top-left, but I don't think it matters much.
Try opening the picture in paint and saving it as a gif. Note of course that changing the file extension doesn't make a difference by renaming it, it is actually still the same file type. So to change a file type, you have to use the "save as" option and select a file type. Try using a gif or a png using this method assuming you haven't so far.
francis.rect.center = [lead_x,lead_y]
You set it as a list. I'm pretty sure it's meant to be a tuple i.e.
francis.rect.center = (lead_x,lead_y)
What does the ".convert" part do in "francis.image = pygame.image.load("francis.png").convert()"
I'm pretty sure it's not meant to be there, try removing it unless you specifically know you need it.
You forgot a crucial line in your code. On the end of the mainloop you should be saying the following line;
pygame.display.flip()
This has something to do with how it loads the pixels from top to bottom or something, I honestly don't know, but I'm pretty sure you need it otherwise the program wont work. I think it replaces pygame.display.update()
How do you change the size of a surface in pygame that has an image (not scaling). When I load an image in pygame the surface becomes the size of the image. I need to change the size of the surface to be the size of a frame (sprite sheet).
Here is code I used to solve issue (thanks to Chris Dennett):
self.surface = pygame.Surface((20, 20))
self.surface.blit(pygame.image.load(imageName).convert_alpha(), (0,0), (0, 0, frameWidth, frameHeight))
For sprite sheets, you have 2 good options.
1) Load spritesheet as one Surface.
When blitting, use the source rect argument. This will blit just one frame, from the sheet.
2) Use subsurfaces.
Load spritesheet as one Surface.
Load a subsurface, of each frame you want : http://www.pygame.org/docs/ref/surface.html#Surface.subsurface
As far as you are concerned, the subsurface is a 'new' surface, with the width and height of the cell. But, it's not duplicate memory. It's linked.
From the docs:
Returns a new Surface that shares its pixels with its new parent. The
new Surface is considered a child of the original. Modifications to
either Surface pixels will effect each other. Surface information like
clipping area and color keys are unique to each Surface.
Create a new surface, passing in the desired width and height as arguments (i.e., how big the sprite is). Then use newsurf.blit(spritesheet, (0, 0), (posX, posY, newsurf.getWidth(), newsurf.getHeight())). Should work. Then you can use newsurf as your sprite. posX and posY should be the x and y you want to blit from in your sprite sheet respectively.