A widescreen hack is an emulator feature that make older games playable on 16:9 aspect ratio.
Most video games before mid-2000s were developed for TVs and monitors with 4:3 aspect ratio. If these games are played on 16:9 aspect ratio, the game is either displayed with black bars on each side or stretched to fill the whole screen. Some emulators however provide a widescreen hack option to make these games look nice on modern monitors.
Some games before mid-2000s do have built-in 16:9 aspect ratio support, but usefulness of this option will vary. Some games just add black bars to top and bottom, while others have very zoomed out camera, so widescreen hacks may still be useful in these games.
A widescreen hack basically hacks camera size and position, so depending on the game there might be graphical glitches.
- 2D sprites/HUDs such as health bars or minimaps might look stretched or displayed on wrong location.
- Enemies or objects outside of 4:3 area might suddenly appear or disappear, because the game skips rendering for offscreen things. Similarly, the screen-wide visual effects such as fade-in and fade-out may only affect the 4:3 area of the screen.
- WideNES: is a novel technique to automatically and interactively map-out NES games, in real time. This allows you to peek beyond the screen boundaries of NES games. Currently only implemented in the emulator ANESE.
- Genesis Plus GX Wide - a fork of Genesis Plus GX with widescreen support. Currently only available as a libretro core.
There are two plugins for Project64 that has widescreen hack support.
- Jabo's Direct3D: The versions included in Project64 2.x has a widescreen hack option, though the plugin itself is buggy compared to versions came with Project64 1.6 (the version before the widescreen hack option was added). Jabo backported this widescreen hack to the 1.6.1 version, which retains the stability of 1.6 with some of the fixes from the other, buggier plugin.
- GLideN64: Currently the only known plugin that can do both widescreen hack and custom texture packs, though the system requirement is much higher than Jabo's. As of May 2018, it now has a new overscan feature that lets the users manually edit offsets to remove black borders/lines around the edges of a game's video output and is compatible with any widescreen hack.
Dolphin has a widescreen hack under graphics options. The aspect ratio option must be set to 'Force 16:9' to make it work.
- PCSX-Reloaded has the widescreen hack in the CPU options.
- ePSXe also has the widescreen hack located within the GTE Hacks options. This feature was added in version 2.0.5.
- DuckStation, a new PSX emulator, also has a widescreen hack located in the Enhancement Settings.
Flycast has widescreen support available via hack that creates widescreen automatically with HUD supports or cheats, use only one of those.
Redream has widescreen support available in the
Manage cheats menu.
RetroWide - forum for discussing widescreen development, both ROM-hacking and technology on the emulator side.