Here is the screenshot:
Look at the right lower corner. See the shining border? It totally corresponds to the cropped part of the image on the left (also in runtime, when move around, it appears and changes together with the cropped image part). It is only there if the bloom is on (I have it with default settings).
Here is the link to the archive with code, eggs and textures, all together:
bloomproblem.zip (hosted on FileFactory).
i have seen similar problems under osx. (not sure if it is the same problem tough).
I have not looked at the code, but this also happens if you use the wrong texture tiling mode. (http://www.panda3d.org/manual/index.php/Texture_Wrap_Modes), it seems that it used WMRepeat instead of WMClamp.
It’s a bug. I need to set the texture to CLAMP mode, and I forgot. If you want, you can edit the code of direct/src/FilterManager.py to insert the relevant mode-setting call. I’ll do this in the next panda version.