On Thu, 08 Mar 2007 23:13:08 +0100, Luis A. Florit <gimpdevel@xxxxxxxxxxxxxxxxxxxxxx> wrote: > My 'solution' (change 'x1, y1,' in line 241 by 'x1, y1+1,') > took care of the shift, but not of the banding. > The homogeneous grey band just moved to the bottom... > (you cannot imagine the mess this does in my code!) This is what's known in the trade as a frig factor! You are arbitarily making an adjustment to correct one subjective error. You will likely find that on a different image it bahaves differently unless you understand why this adjustment is necessary and that +1 is a generally valid fix. I cant comment on whether this is a bug in the tile code of the example or elsewhere. I suggest you look at some of the built in plugins. I think most of the effects on the filters menu are implemented as plugins that are part of the gimp distribution. There are some differences in integrating external plugins but it's pretty much the same thing in the plugin code so you may be able get some clues on what you are trying to do from the existing plugins. Be warned there are bugs in there two ;) I did some revectoring and tidy up work on the convolution plugin last year and got told off for not testing it and introducing bugs. It turned out the bugs have been there since 1997. My objective was to make the code more readable and maintainable and to generalise the matrix routines to handle larger dimensions. I did not attempt to fix these anomolies. My initial idea was to write a new plugin but I gave up since the documentation was totally inadequate, out of date and sometimes inaccurate. I decided it would take more time than I had available. I hope you have more luck. gg _______________________________________________ Gimp-developer mailing list Gimp-developer@xxxxxxxxxxxxxxxxxxxxxx https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer