Mesh Issue texture coordinates with strip whitespace enabled

vblack

It seems to that the spine runtime have issue with UV coordinates when strip whitespace is enabled.

Exporting with 'strip whitespace' disable works, but in my case there a lot of 200x200 sprites in a big 2048x1553 image.

The rendering works in spine editor, but in the runtime it is wrong (using C runtime, but since I don't have any other viewer, I assume the issue is the same for other).

Also, if I disable the 'strip whitespace', it works.

If I crop the manually the image, the spine editor have the same wrong rendering than the runtime.

Runtime is 3.2

vblack

Pharan

This is the current design. Spine has always behaved this way.

The packer doesn't pack against the outer borders of the mesh, and the whitespace stripping information isn't saved in the skeleton data.
This is partly because atlasing within Spine is not a given. Some engines could just as well be using a runtime packer, or no packing at all. And mapping in some of those cases as is using trimmed images would cause the mesh UVs to bleed into other images packed on the atlas.

The ideal setup is to pre-trim/pre-strip your images before bringing them into Spine.

DonMizzi

Hi, I resume this post because I would like to have some information.

For me, it would be useful to use the whitespace strip while using the meshes.

We use the skins, and for flexibility, body parts are drawn inside a bounding box.

In this way we can have body parts with different dimensions for all characters (inside the area of the bounding box), using the same bones positioning.
Small variations, but useful for characterizing the skin character.

The bounding box, logically, is slightly larger than the larger image used for that part of the body.

We work with Cocos2d-x 3.15 and Spine 3.5.35.

Our export creates a .atlas file that contains all the information about the original image (size and offset)

Technically, it would be possible to recreate the original image when the image atlas is extracted, right?

Thank you
Don

Nate

You mesh image is rectangular and has whitespace. You then define a hull inside the rectangle which is your mesh. You can only strip whitespace from the rectangle edge to the bounding rectangle of your mesh hull. If you strip further whitespace, then your mesh UVs will sample neighboring regions on the atlas image, or sample off the edge of the image. It is common to have 1-2px of whitespace from the mesh hull to the non-transparent pixels to avoid filtering artifacts at the mesh edge, so stripping all whitespace would be bad.

The texture packer needs to know about the mesh UVs so it can strip the right amount of whitespace. We have plans to do this, but all sorts of things seem to steal our time away! We will get to it, promise! 🙂