Behavior of Runtime loaded Textures

Does WL.texture.load just keep filling up the uncompressed texture space until a WL.scene.load happens?
Can the space used by a texture be dellocated when it is not in use?

separately, can an image be runtime-drawn onto a texture like a small decal onto a larger texture image?

Yes and no, currently there’s no way to deallocate.

You can, theoretically overwrite a texture like this:

WL._images[yourTex._imageIndex] = newImage;
yourTex.update(); //writes newImage to the texture space that was previously used by yourTex

ok! reuse is also ok!

separately, can an image be runtime-drawn onto a texture like a small decal onto a larger texture image?

Decals unfortunately are not supported yet, you could add a small plane with the texture on it and render that over other objects, though.

I’m actually asking about writing into the texture buffer

Oh, well you can write your Image to a Canvas and upload the canvas as texture