Ok, so you chose the whole column, that's a good idea.
To optimize further, you can tell the OS to invalidate only that column:
Thank you for the tip. I remember now that you had already given it to me, but I had forgotten it.
Here is a new version of the project. Now the user can change the size and the style of the grid. The pictures are created by the program
imagefactory. If you want to play with it, you have to copy
arial.ttf in
imagefactory folder, and to use your own wood texture. I removed these files from the ZIP file to make it not too heavy.
I am glad of the result, except maybe for the colors. The choice of colors is a pain. If I would listen to myself, I would use only shades of gray.
The question about animation is solved. But if ever you have other ideas, I would be glad, of course, to hear them.
Regards.
Roland
P.-S. I also deleted the 32x32 pictures, otherwise the attachment was still too big.