I was giving it a thought today as I am ready to make the necessary GUI modifications to put the object grabber in I2012. While doing so I realized that the user selection of transparent colour should not be mandatory as it is now: users should also be able to use the info that is originally in the hires picture’s bitmap using colour 0 as empty.
However, the latter method alone would not satisfy me as I’ve come across hires where one of the colours in video or colour RAM was the same as colour 0 (background). In these scenarios only part of what is perceived as transparent/empty would really be transparent/empty.
Look at the image below for which I changed the background colour from blue to black: there are some parts of the oceans that are blue, but do not use colour 0. If you assume colour 0 to be transparent, then you would expect all blue areas to have become transparent if you did not know that somewhere colours 1, 2, or 3 are also set to blue.
At the same time, there are cases in which as example you have a black background (colour 0 is black) and objects with black pixels in them that should not be transparent (that set colour 1, 2, or 3 to black).
I will do the update in the object grabber first then 🙂