Pygame: Text losing anti-aliasing when blitting to SRCALPHA surface - python-3.x

I recently changed the way my pygame game handles menus. Any text I'm rendering is blit to a surface called guiSurface before it is blit to the display (screen).
The problem is that this causes the text to appear aliased, whereas blitting it directly to the display didn't have this issue.
With guiSurface (screenshot):
menuFont = pygame.font.Font('assets/MarkPro.otf',15,bold=False,italic=False)
menuText = menuFont.render(version, 1, (255,255,255))
guiSurface.blit(menuText,(790-(menuText.get_size()[0]),475))
screen.blit(guiSurface, (0,0))
pygame.display.update()
Directly to display (screenshot):
menuFont = pygame.font.Font('assets/MarkPro.otf',15,bold=False,italic=False)
menuText = menuFont.render(version, 1, (255,255,255))
screen.blit(menuText,(790-(menuText.get_size()[0]),475))
screen.blit(guiSurface, (0,0))
pygame.display.update()
I've tried using .convert() and .convert_alpha() on both the menuText and guiSurface surfaces, after line 2 in both code snippets, but to no avail. And I have no idea at which point the anti-aliasing is lost.
Help is of course appreciated, and thanks in advance.

The fault is mine. I didn't clear guiSurface after blitting it to the display, meaning I was drawing over what was already there instead of a fresh surface.

Related

read png file names from txt files in pygame [duplicate]

I would like to know how to draw images using pygame. I know how to load them.
I have made a blank window.
When I use screen.blit(blank, (10,10)), it does not draw the image and instead leaves the screen blank.
This is a typical layout:
myimage = pygame.image.load("myimage.bmp")
imagerect = myimage.get_rect()
while 1:
your_code_here
screen.fill(black)
screen.blit(myimage, imagerect)
pygame.display.flip()
import pygame, sys, os
from pygame.locals import *
pygame.init()
screen = pygame.display.set_mode((100, 100))
player = pygame.image.load(os.path.join("player.png"))
player.convert()
while True:
screen.blit(player, (10, 10))
pygame.display.flip()
pygame.quit()
Loads the file player.png.
Run this and it works perfectly. So hopefully you learn something.
Images are represented by "pygame.Surface" objects. A Surface can be created from an image with pygame.image.load:
my_image_surface = pygame.load.image('my_image.jpg')
However, the pygame documentation notes that:
The returned Surface will contain the same color format, colorkey and alpha transparency as the file it came from. You will often want to call convert() with no arguments, to create a copy that will draw more quickly on the screen.
For alpha transparency, like in .png images, use the convert_alpha() method after loading so that the image has per pixel transparency.
Use the appropriate conversion method for best performance:
image_surface = pygame.load.image('my_image.jpg').convert()
alpha_image_surface = pygame.load.image('my_icon.png').convert_alpha()
A Surface can be drawn on or blended with another Surface using the blit method. The first argument to blit is the Surface that should be drawn. The second argument is either a tuple (x, y) representing the upper left corner or a rectangle. With a rectangle, only the upper left corner of the rectangle is taken into account. It should be mentioned that the window respectively display is also represented by a Surface. Therefore, drawing a Surface in the window is the same as drawing a Surface on a Surface:
window_surface.blit(image_surface, (x, y))
window_surface.blit(image_surface,
image_surface.get_rect(center = window_surface.get_rect().center))
Minimal example:
import pygame
pygame.init()
window = pygame.display.set_mode((300, 300))
clock = pygame.time.Clock()
pygameSurface = pygame.image.load('apple.png').convert_alpha()
run = True
while run:
clock.tick(60)
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
window.fill((127, 127, 127))
window.blit(pygameSurface, pygameSurface.get_rect(center = window.get_rect().center))
pygame.display.flip()
pygame.quit()
exit()
pygame.image.load is bale to load most images. According to the documentation the following formats are supported: JPG, PNG, GIF (non-animated), BMP, PCX, TGA (uncompressed), TIF, LBM (and PBM), PBM (and PGM, PPM), XPM.
If you want to use images in PyGame that are loaded with other libraries, see:
PIL and pygame.image
How do I convert an OpenCV (cv2) image (BGR and BGRA) to a pygame.Surface object
For information on loading Scalable Vector Graphics (SVG) files, see:
SVG rendering in a PyGame application
Loading animated GIF files is presented at:
How can I load an animated GIF and get all of the individual frames in PyGame?
How do I make a sprite as a gif in pygame?
Or see how to load NumPy frames:
Pygame and Numpy Animations
After using blit or any other update on your drawing surface, you have to call pygame.display.flip() to actually update what is displayed.

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I am trying to make an image slide show application using Tkinter and Pillow. I would like the image to go full screen, so currently my code looks like this (I think these are all the important bits, ask me if you need to see more):
canvas = Canvas(root, width=screenwidth, height=screenheight, bg=‘black’)#screenwidth and height previously assigned (checked to be correct) variables containing screen dimensions.
image = image.resize((resizew, resizeh) Image.ANTIALIAS)
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No matter what settings I change there is always some form of grey bar around the edge of the window. I have tried changing the window size, changing the canvas size, setting the window geometry manually using root.geometry to no avail. However, some of the combinations of settings lead to there being fewer bars; I have seen between 1 and 3. Pictures of the output in its current state are attached. There are no errors in the shell, not (currently) is there a border on the left of the image
[1]: https://i.stack.imgur.com/1DLfg.jpg
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ret,osu = cv.threshold(blur,0,255,cv.THRESH_BINARY+cv.THRESH_OTSU)
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So I am making a Frogger game, but have run into a problem. For the collision detection, I am using the following to check if one Tkinter canvas object is overlapping another:
canvas.find_overlapping(*canvas.bbox(imageObj))
However, I made the background a canvas object as well:
background = self.canvas.create_image(0, 0, image = self.imageData["Background"], anchor = "nw")
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Hia.
I am using some round rect buttons with own images for their states. Each time am displaying a different view for some stuff, the buttons become white and my images are fading in briefly later.
The problem occurs only with the UIModalTransitionStyleCrossDissolve animation.
The other 3, UIModalTransitionStyleCoverVertical, UIModalTransitionStyleFlipHorizontal and UIModalTransitionStylePartialCurl, don't show this effect.
The effect would be ok, ok if the starting color would be black. I didn't find any way to change that color in IB. Where does it come from? Any idea?
Tried to set the background over the inherited properties of UIImage, but he simply ignored it. Switching the Round rect button to a custom one solved it. Leaves the question what to do if I want a round rect. A black background image didn't help. He seems to use the background color to fade.

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