Gopher2600 v0.12 is released. Gopher2600 is an emulator for the Atari 2600. Whilst the performance is not as efficient as some other emulators it is none-the-less suitable for playing games, on a reasonably modern computer, at the required 60fps. (The development machine for Gopher2600 has been an i3-3225, dating from around 2012.)

Gopher2600 v0.12 changelog:
Performance improvements
- With the Linux binary on my development machine
- Typical 2600 ROM: about 9% improvement
- ROM using the ARM coprocessor: about 20% improvement
CRT improvements
- CRT sharpness control
- Scanline and ShadowMask coarseness controls
- Bilinear filter. Improves emulation of brick effect in Zookeeper
- Sizing of playmode screen is now limited to whole integers
- This prevents color banding in some ROMs
Television
- Screen roll
- PAL signal detection improved. Eliminated a false positive
MovieCart updated to match reference implementation
Input buffer lowered to five frames. User input should feel better
Rewinding of PlusROM carts should now work in all instances

Download: Gopher2600 v0.12
Source:Here