How to copy an [elliptical] region of pixels from image to canvas

desertbeaver

Hello! I want to copy an ellipse of pixels from an image or Capture event to my processing sketch. the copy() function only allows for rectangles and the get() function only copies a single pixel value. Is there a way to do this?

TfGuy44

Look into using mask().

GoToLoop

https://Forum.Processing.org/two/discussion/5618/crop-image#Item_26

jeremydouglass

For a mask()-based example, see:

https://forum.processing.org/two/discussion/comment/77997/#Comment_77997

You would use ellipse() instead of triangle() -- or draw any mask shape you want, really.

desertbeaver

I was hoping to actually copy the pixels from the image to the ellipse at location mouseX, mouseY and use it sort of as a paintbrush. This is a good start though, thank you so much!

jeremydouglass

In the linked example, change:

image(photo, 0, 0);

To:

image(photo, mouseX, mouseY);

...paintbrush. Big, awkward paintbrush.

You may want to use imageMode(CENTER) in setup.

desertbeaver

Yes! thank you jeremydouglass!