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canvas.draw_image() function does not work
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Hey there,
I have a problem with the following code:import canvas as cv # creates canvas w = 200 h = 500 cv.set_size(w, h) # size of the image img_w = 190 img_h = 490 cv.begin_updates() # draws a white rectangle as the canvas background cv.set_fill_color(1, 1, 1) cv.fill_rect(0, 0, w, h) # draws an image onto the canvas cv.draw_image("image.png", 0, 0, img_w, img_h) cv.end_updates()
Whenever is use the canvas.draw_image() function, my Pythonista crashes. This seems to be not because of the image that I‘m trying to draw, since I‘ve tried out other images and even an empty string as the 1. argument too. It didn‘t even give me an error, it just closed the program.
Am I just not using the function correctly or is there something else I need to add?
I would be really happy if someone could help me out.
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https://omz-software.com/pythonista/docs/ios/canvas.html#canvas.draw_image
You need a "named image" not an image file name.
The first two functions of https://forum.omz-software.com/topic/2332/can-t-subclass-scene-rect-in-1-6-beta/3 might be useful. -
@ccc said
You need a "named image"
What is that? For me, in Ui.Image.named(name), name is a file name
And the crash does not have any explanation in faultlog, only "abort"????
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@Trüff perhaps a canvas bug, try this (with, of course, your own file name)
img = ui.Image.named('kitty.JPG') clipboard.set_image(img) #cv.draw_image("kitty.JPG", 0, 0, img_w, img_h) cv.draw_clipboard(0, 0, img_w, img_h)
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https://omz-software.com/pythonista/docs/ios/ui.html#ui.Image.named
-->cv.draw_image(ui.Image.named("image.png"), 0, 0, img_w, img_h)
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@ccc that does not work, draw_image wants a string as first argument
cv.draw_image(ui.Image.named("kitty.JPG"), 0, 0, img_w, img_h) TypeError: argument 1 must be str, not _ui.Image
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@Trüff could you tell me if this solves your problem, thanks
img = ui.Image.named('image.png') clipboard.set_image(img) cv.draw_clipboard(0, 0, img_w, img_h)
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@cvp Hm… Well, it does draw the image onto the canvas. But the image I want to draw is transparent and apparently it just sets a white background for images that are saved into the clipboard. So when I draw the clipboard with the image inside of it, the picture is not transparent anymore.
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Keep the
alpha
low on the background color like: -
@ccc Ok thank you. I‘m going to read the documentary on these modules first.
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@ccc said
Keep the alpha low on the background color
If the image he wants to draw is transparent, its background color has already a low alpha.
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@Trüff I don't know if you really need a canvas, else, please try this
import ui v = ui.View() v.background_color = 'yellow' iv = ui.ImageView() iv.background_color = 'red' iv.image = ui.Image.named('image.png') wi,hi = iv.image.size iv.frame = (10,10,150,150*hi/wi) v.add_subview(iv) v.present('fullscreen')
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@cvp This also doesn‘t work with transparent pictures for me. However, I tried out your previous idea of saving the image into the clipboard and drawing the clipboard but I used the class
Image
from thePIL
module instead of the one from Pythonista‘sui
module and that worked. Thank you! -
@Trüff saiD
This also doesn‘t work with transparent pictures for me
Weird, for me it works, the image of my example has a transparent background, here in red
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@Trüff said
but I used the class Image from the PIL module instead of the one from Pythonista‘s ui module and that worked
👍