I am learning pygame and want a graphic for a button with the three states: normal, hover, and pressed. I have an image like this one ...
... and I want to get a new Surface using a portion of it.
I'm loading the image with this code:
buttonStates = pygame.image.load(os.path.join('image','button.png'))
How can I make a new surface using just a portion of that graphic?
cropped = pygame.Surface((80, 80))
cropped.blit(buttonStates, (0, 0), (30, 30, 80, 80))
The blit method on a surface 'pastes' another surface on to it. The first argument to blit is the source surface. The second is the location to paste to (in this case, the top left corner). The third (optional) argument is the area of the source image to paste from -- in this case an 80x80 square 30px from the top and 30px from the left.
You can also use the pygame.Surface.subsurface method to create subsurfaces that share their pixels with their parent surface. However, you have to make sure that the rect is inside of the image area or a ValueError: subsurface rectangle outside surface area will be raised.
subsurface = a_surface.subsurface((x, y, width, height))
There are 2 possibilities.
The blit method allows to specify a rectangular sub-area of the source _Surface:
[...] An optional area rectangle can be passed as well. This represents a smaller portion of the source Surface to draw. [...]
In this way you can blit an area of the source surface directly onto a target:
cropped_region = (x, y, width, height)
target.blit(source_surf, (posx, posy), cropped_region)
Alternatively, you can define a subsurface that is directly linked to the source surface with the subsurface method:
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.
As soon as a subsurface has been created, it can be used as a normal surface at any time:
cropped_region = (x, y, width, height)
cropped_subsurf = source_surf.subsurface(cropped_region)
target.blit(cropped_subsurf, (posx, posy))
I think the best way to do it is crop the image of these 3 kind of buttons in a external program and load in different surface instead use pygame to crop it
Related
I have a project where i have to create a 4 way split screen using pygame. On this screen i have to draw the same image on each of the screen just have different view of the image. I just can not figure out how to create this 4 way split screen using pygame.
I need my screen to be divided like above so i can draw my points onto each section.
I have been looking around and I can not find anything like this so any help would be great
thanks
In addition to the surface you have that gets rendered to the display, likely called something like screen, you should create another surface which all of the "action" gets drawn to. You can then use a Rect object for each quadrant of the screen which will represent the "camera" (assuming each quadrant doesn't necessarily need to show exactly the same image). When you draw back to screen, you use each camera Rect object to select a portion of the game space to draw to a specific quadrant.
# canvas will be a surface that captures the entirety of the "action"
canvas = pygame.Surface((800, 600))
# the following are your "camera" objects
# right now they are taking up discrete and even portions of the canvas,
# but the idea is that they can move and possibly cover overlapping sections
# of the canvas
p1_camera = pygame.Rect(0,0,400,300)
p2_camera = pygame.Rect(400,0,400,300)
p3_camera = pygame.Rect(0,300,400,300)
p4_camera = pygame.Rect(400,300,400,300)
On each update, you would then use these "camera" objects to blit various portions of the canvas back to the screen surface.
# draw player 1's view to the top left corner
screen.blit(canvas, (0,0), p1_camera)
# player 2's view is in the top right corner
screen.blit(canvas, (400, 0), p2_camera)
# player 3's view is in the bottom left corner
screen.blit(canvas, (0, 300), p3_camera)
# player 4's view is in the bottom right corner
screen.blit(canvas, (400, 300), p4_camera)
# then you update the display
# this can be done with either display.flip() or display.update(), the
# uses of each are beyond this question
display.flip()
There is no functions to split screen. But you can draw 4 views directly on screen or you can draw on 4 surfaces (pygame.Surface) and than blit surfaces on screen.
Since you were looking for a way to split the screen in to 4 sections and draw some points on to them I'd suggest creating 4 subsurface surfaces of the original "canvas" image for convenience.
These surfaces would act as your player(split screen) canvasses which can easily be modified.
This will enable the usage of normalized coordinates for player specific drawing purposes.
Assuming you have a screen surface set up
# Image(Surface) which will be refrenced
canvas = pygame.Surface((800, 600))
# Camera rectangles for sections of the canvas
p1_camera = pygame.Rect(0,0,400,300)
p2_camera = pygame.Rect(400,0,400,300)
p3_camera = pygame.Rect(0,300,400,300)
p4_camera = pygame.Rect(400,300,400,300)
# subsurfaces of canvas
# Note that subx needs refreshing when px_camera changes.
sub1 = canvas.subsurface(p1_camera)
sub2 = canvas.subsurface(p2_camera)
sub3 = canvas.subsurface(p3_camera)
sub4 = canvas.subsurface(p4_camera)
Now drawing on any of of the subsurfaces with these normalized coordinates
# Drawing a line on each split "screen"
pygame.draw.line(sub2, (255,255,255), (0,0), (0,300), 10)
pygame.draw.line(sub4, (255,255,255), (0,0), (0,300), 10)
pygame.draw.line(sub3, (255,255,255), (0,0), (400,0), 10)
pygame.draw.line(sub4, (255,255,255), (0,0), (400,0), 10)
# draw player 1's view to the top left corner
screen.blit(sub1, (0,0))
# player 2's view is in the top right corner
screen.blit(sub2, (400, 0))
# player 3's view is in the bottom left corner
screen.blit(sub3, (0, 300))
# player 4's view is in the bottom right corner
screen.blit(sub4, (400, 300))
# Update the screen
pygame.display.update()
Note that modifications to the subsurface pixels will affect the canvas as well. I'd recommend reading the full documentation on subsurfaces.
How does Pygame's "rect.inflate_ip" function work?
In this code, I am trying to inflate this rectangle by some value zoom:
rect = pygame.draw.rect(screen,block.color,(block.x+scx,block.y+scy,10,10))
rect.inflate_ip(zoom,zoom)
But this does not have any effect. Why?
Print rect before and after inflate_ip and you'll see the difference. Of course, it doesn't affect the rectangle drawn on the screen. pygame.draw.rect does not generate an object. This function fills a rectangular area on the screen and returns that area. You have to create a pagame.Rect object and use that for drawing. e.g.:
rect = pygame.Rect(block.x+scx, block.y+scy, 10, 10)
rect.inflate_ip(zoom, zoom)
pygame.draw.rect(screen, block.color, rect)
I am trying to find the point where a line collides with a brick in the arkanoid that i am making. The most logical way i found is getting the mask from the line and use collidemask as it returns the point. Well as i tried with this:
linemask = pygame.mask.from_surface(pygame.draw.line(screen, (0,0,0), bola.line[0], bola.line[1], 2))
it gave me this error:
TypeError: argument 1 must be pygame.Surface, not pygame.Rect
meaning that the input(in this case the line) can't be a rect but needs to be a surface. Do you know how to get the surface from a rect or any alternative solution ?
pygame.draw.line draws on a Surface and returns the affected area in form of a Rect object.
The Surface you drew on is screen. So it's screen you want to create a mask from. Alternatively, create a new Surface that you use pygame.draw on and create a mask from it. Or create a mask from the subsurface of the screen (so you don't have to create a mask from the whole screen), like this:
rect = pygame.draw.line(screen, (0,0,0), bola.line[0], bola.line[1], 2)
surface = screen.subsurface(rect)
mask = pygame.mask.from_surface(surface)
How can I define a rect collision detection smaller than image in pygame?
I'd like to have a collision patter like the second image , but I'm having a cut image when a try to set the width and height in the method rect.
When I try to set using image size, I have the collision detection in red
self.rect = pygame.rect.Rect(location, self.image.get_size())
If I set the size using width and height, I just have the third image
self.rect = pygame.rect.Rect(location, (32, 150))
I really wouldn't like to use pixel perfect collision, because is the slowest collision detection, so someone have some idea how can I achieve the second image collision approach using Rect? Thanks.
It seems that you are using pygames built in sprite module. (Please correct me if I am wrong)
You might know that each sprite consist of an image (which is drawn on a surface) and a rect object (sets location and size (!) of the image).
As Luke Taylor suggested, you could create a new rect object in your player class …
self.collideRect = pygame.rect.Rect((0, 0), (32, 150))
… and set its location (according to your graphic) to
self.collideRect.midbottom = self.rect.midbottom
Every time you change the position of your player you must call this line too, so your self.collideRect rect object "moves" with your player on screen.
To test if a point (e.g. the mouse coordinates) is inside the self.collideRect, call
if self.collideRect.collidepoint(x, y) == True:
print("You clicked on me!")
Try drawing a completely new rectangle separate from the image that is behind the image, but who's location is constantly set to that if the image.
def rotate(self):
#Save the original rect center
self.saved_center=self.rect.center
#Rotates a saved image every time to maintain quality
self.image=pygame.transform.rotate(self.saved_image, self.angle)
#Make new rect center the old one
self.rect.center=self.saved_center
self.angle+=10
When I rotate the image, there is a weird shifting of it despite the fact that I'm saving the old rect center and making the rotated rect center the old one. I want it to rotate right at the center of the square.
Here's what it looks like:
http://i.imgur.com/g6Os9.gif
You are just calculating the new rect wrong. Try this:
def rotate(self):
self.image=pygame.transform.rotate(self.saved_image, self.angle)
self.rect = self.image.get_rect(center=self.rect.center)
self.angle+=10
It tells the new rect to center itself around the original center (the center never changes here. Just keeps getting passed along).
The issue was that the self.rect was never being properly updated. You were only changing the center value. The entire rect changes as the image rotates because it grows and shrinks in size. So what you needed to do was completely set the new rect each time.
self.image.get_rect(center=self.rect.center)
This calculates a brand new rect, while basing it around the given center. The center is set on the rect before it calculate the positions. Thus, you get a rect that is properly centered around your point.
I had this issue. My method has a bit of a different purpose, but I solved it quite nicely.
import pygame, math
def draw_sprite(self, sprite, x, y, rot):
#'sprite' is the loaded image file.
#'x' and 'y' are coordinates.
#'rot' is rotation in radians.
#Creates a new 'rotated_sprite' that is a rotated variant of 'sprite'
#Also performs a radian-to-degrees conversion on 'rot'.
rotated_sprite = pygame.transform.rotate(sprite, math.degrees(rot))
#Creates a new 'rect' based on 'rotated_sprite'
rect = rotated_sprite.get_rect()
#Blits the rotated_sprite onto the screen with an offset from 'rect'
self.screen.blit(rotated_sprite, (x-(rect.width/2), y-(rect.height/2)))