Pass $metadata to intermediate_image_sizes_advanced filter

[amereservant]

I'm requesting that the following patch be added, which simply passes the $metadata for the image to be used for the new post thumbnail sizes to any filters hooking the intermediate_image_sizes_advanced filter in the wp_generate_attachment_metadata function.

The purpose of this is for altering the size of a custom thumbnail size based on the given image's dimensions. For example, I have a need for an post image size that's a minimum dimension size of 200px. The default behavior will allow me to specify a maximum dimension size, but not a minimum.
So by hooking this filter, I can alter the $sizes array and correct the size of my custom post thumbnail size based on the current image's dimensions.

[amereservant]

Proposed filter variable

[markoheijnen]

Interesting idea. You can't use the filter 'image_resize_dimensions' because of not knowing the image size and a custom image editor for this seems redundant.

[amereservant]

Replying to markoheijnen:

Interesting idea. You can't use the filter 'image_resize_dimensions' because of not knowing the image size and a custom image editor for this seems redundant.

Yeap. I discovered it after hacking Viper007Bond's Regenerate Thumbnail plugin and trying to make a basic size check. I realized that a simple post thumbnail size hook wasn't possible, yet it could be by passing the $metadata as a var parameter to the filter.

It doesn't hurt the performance any to add this and it'd be useful to us geeks that dive way too far into WP code, attempting to write proper plugins.

[DrewAPicture]

image.php.patch​ seems pretty straightforward, testing against the passed $metadata works for me.

[wonderboymusic]

In 34007:

In wp_generate_attachment_metadata(), also pass $metadata to the intermediate_image_sizes_advanced filter.

Props amereservant, wonderboymusic.
Fixes #23401.