Here is the code I wrote as my own special scaler for old video games.

Features:
- makes dithering look good and makes curves very smooth.
- smooths horizontal and vertical scrolling.
- does not create new colors, hence is compatible with paletted video.

As a bonus, here are some palettes for game boy games.
you can use them by doing for example
xxd -rp <gb.warm-on-cool >~/.mednafen/palettes/gb.pal
if you don't have xxd the program xtob that I included will work, like
xtob <gb.warm-on-cool >~/.mednafen/palettes/gb.pal

You can contact me on gmail at 'oren.watson'.

Other than the code I copied and modified from mednafen, (video.cpp),
which is under the GNU General Public License version 2 as per share-alike,
This code (oren4x.cpp, oren4x.h, xtob.c) is licensed to you herein under the 
CC0 license, e.g. all rights are waived, and you may modify or build 
upon this code, incorporate it into another project, even a commercial one, 
etc, without limitation, you do not even need to credit me.
Other licenses are also available upon request.