Bug related to PImage::copy() of images with transparency?

[glv]

Hello @yodan,

This is a related topic:

Alpha of Zero in first pixel makes whole image opaque

When I use an image as a background, then set the alpha values for all pixels in a second image to something low, then draw that image, I can see “through” the second image to the background, just as I would expect. Here, the mandrill is the second image, with alpha set to 0x40 for every pixel: [FaintMandrill] If I set alpha to 0x00 for the very first pixel, the entire mandrill becomes opaque: [FullMandrill] I’m using Processing 3.5.4. Here’s my code: PImage imgFace; PImage imgMandrill; …

https://processing.org/reference/PImage_copy_.html states:

No alpha information is used in the process, however if the source image has an alpha channel set, it will be copied as well.

Another topic that is related:
https://discourse.processing.org/t/pixel-processing-grabbing-the-canvas-and-wheres-the-alpha/7162

:)