Remember the guy that speedran Need For Speed: Most Wanted using Half-Life movement? Well I interviewed him and he has his sights set on some pretty big games.
"Zolika is the mad genius behind the GTA and Need for Speed Half-Life Movement Mods," Jeepy explains. Zolika made a GTA San Andreas mod that lets you rocket jump to create some serious speed. "Eventually, Zolika joined our community and started ramping up work on the mod to make it possible to speedrun as well as adding the mixed movement."
As to how the mod actually works, one of Jeepy's moderators, Bryan, says it depends on the game. "Some games have adequate modding tools that give you enough access to the movement controller to implement Half-Life movement physics without doing a whole lot of 'special' stuff."
However, it's not always that easy, which is where modders like Zolika come in. "For some games that don't give you enough modding access, you have to inject code into the running process to get things you need (like view angles, camera matrices, position and velocity data and the ability to manipulate it, etc)," Bryan explains. "This is a pretty advanced reverse engineering effort, but some people in the community (Zolika, ScriptedSnark, Chloe) are just awesome at it."
To my great shame, I've not actually played any of the Half-Life games fully, so I didn't understand what was so special about its movement. "Half-Life 1 has bunny hopping," Jeepy explains. "It’s building momentum by strafing left and right in the air while chaining strafes together with jumps in between. What makes these mods unique is that while they include the bunny hop mechanic from Half-Life 1, they also include accelerated back hopping (ABH) from Half-Life 2 which gives you exponential speed gain between hops."
If you're thinking that sounds a bit broken, you'd be correct. "In an effort to fix bunny hopping in Half-Life 2, Valve accidentally made it to where you not only gained speed while going backwards, but the speed gained
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