## Bisection Search Like A (Human) Boss

Bisection search, or binary search for us developers, is a technique for finding the best value within a given range of values. This post describes tips for when you need to bisection search manually by hand (by “feel”), as opposed to when it can be automated by, say, a computer algorithm.

Bisection search, or binary search for us developers, is a technique for finding the best value within a given range of values.  Technically speaking, Wikipedia says the “bisection method in mathematics is a root-finding method that repeatedly bisects an interval and then selects a subinterval in which a root must lie for further processing.” This post describes tips for when you need to bisection search manually by hand (by “feel”), as opposed to when it can be automated by, say, a computer algorithm.

For example, say you’re very thirsty and need water fast so you pour yourself a glass of water: Pour too fast and it spills but too slow and it takes too long. You want to pour fast enough to quench your thirst as soon as possible but not so fast that it spills. The speed of pouring is your range of values (eg. slow to fast) and the consequences of the speed of pouring (how long it takes and if it spills) are your criteria to decide the best value. You try pouring the glass slowly and it’s too slow: Pour faster. You try pouring the glass faster and it spills: Pour slower but faster than the first time. You try pouring the glass “just right”: It’s fast enough and doesn’t spill. You’ve found the best pouring speed by bisection search!

Update 2017-10-26: Added sections: Bisection Hacks, and Case Study: Tuning Force Feedback Parameters in GTR2 – FIA GT Racing Game.

## Secrets of GTR2

Welcome to Secrets of GTR2 where I will be recording my experience, tips, tricks, resources and other helpful information as I get into GTR2.

### Secrets of GTR2

Welcome to Secrets of GTR2 where I will be recording my experience, tips, tricks, resources and other helpful information as I get into GTR2.

Secrets of X is a series of blog posts I started with Secrets of iRacing and which has grown to include Secrets of GTR2, Secrets of Automobilista, and Secrets of rFactor 2. The “secrets” part is a little dramatic but there are quite a few tips and tricks I think new users will find very valuable and interesting.

Update 2018-06-13: Fixed PLR link for FFB settings for Original Cars under Force Feedback > Shovas Custom FFB Files.

2018-06-08 – 3: Updated Mod Spotlight > EEC GT3 V3 with some potentially helpful notes on how to get started installing it.

Update 2018-06-08 – 2: Added my NVIDIA Inspector customization notes for improved graphics under Getting Started > Modernizing > NVIDIA Inspector Settings.

Update 2018-06-08: I’ve now certified my new FFB settings for DTM Classics cars which are now rebased on the benchmark 2005 FiaGT Mod FFB settings. Check out Force Feedback > Shovas Custom FFB Files for the PLR download.

Update 2018-06-04: There’s an update over on my NoGripRacing.com Is Down post. Check it out for the latest on what happened to NoGripRacing.com and details on how we might be able to help recover the site! PS. There are full backups! Catch? Sounds like unpaid bills to pay before they’re released :(

Update 2018-06-03: I’ve now certified my new FFB settings for HQ Cars which are now rebased on the benchmark 2005 FiaGT Mod FFB settings. Check out Force Feedback > Shovas Custom FFB Files for the PLR download.

Update 2018-05-30: NoGripRacing.com has been down for most of today. Anyone have any news? It would be a crying shame if it were permanently lost – there were so many downloads there and lots of good people. I would be happy to provide some kind of mirror hosting if anybody knows how to get in contact with the owner.

Update 2018-05-25: I’ve now certified my FFB settings for Original Cars. Check out Force Feedback > Shovas Custom FFB Files for the PLR download.

Update 2018-05-21 – 2: I have now certified my FFB PLR for the FiaGT 2005 Mod. Check out Force Feedback > Shovas Custom FFB Files for the PLR download. In my opinion, FiaGT 2005 is currently the best mod available. It doesn’t try to do too much, just provide the FIA GT 2005 season, and that’s how it keeps everything tight and polished and feeling high quality. Give it a try if you haven’t already, it’s well worth it!

Update 2018-05-21: Updated Force Feedback > Shovas Custom FFB Files for FiaGT 2005 Mod. This is now my best feeling FFB + Mod set.

Update 2018-05-13: Added David Littman’s mod bounty to the GTR2 Mod Bounty Program.

Update 2018-03-25: Introducing the GTR2 Mod Bounty Program: A system to match pledgers with modders to improve the game we all love, GTR2. Take a look at the available bounties and consider pledging to see if we can gather some interest in keeping GTR2 alive and kicking!

Update 2018-03-24: Updated Force Feedback > The GTR2 Force Feedback Engineer with advice for FFB adjustments when your wheel goes numb, like it’s clipping, even though you’re not at max FFB strength.

Update 2018-03-23: Correction on Troubleshooting > Graphics driver crash and black screen freeze while driving: This problem seems to have been due to bad files in my GTR2 folder. I started again with a clean, brand new GTR2 installation, and tested with crash-prone cars and tracks and haven’t had a black screen freeze crash again, yet *fingerscrossed*.

Update 2018-03-05: Updated Mod Spotlight > DTM Classics Mod to (1) recommend NOT raising Max Vehicles on tracks to avoid some pit issues, and (2) provided a ‘plain’ championship that allows for custom race durations (in minutes) and avoids repeating tracks. Added Troubleshooting > Graphics driver crash and black screen freeze while driving.

Update 2018-02-16 – 3: Updated Force Feedback > Shovas Custom FFB Files for WSGT Mod cars but unfortunately, due to consistency issues with the cars physics and handling in the mod, FFB could be tuned for one car but not for all. You’d have to tune each car separately which I’m not willing to put the effort into. There are also tire heating/cooling problems with the mod. Sadly, will have to avoid this mod for now.

Update 2018-02-16 – 2: Updated Force Feedback > Shovas Custom FFB Files for EEC GT3 cars bringing it to a Candidate quality level.

Update 2018-02-16: Added Force Feedback > The GTR2 Force Feedback Engineer, inspired by the Project Cars 2 Race Engineer, which is an in-game question and answer car setup tweaking interface, to help narrow down how to tune force feedback in GTR2.

Update 2018-02-15: Added All Cars (Baseline) FFB settings under Force Feedback > Shovas Custom FFB Files for those people who just one one, simple FFB setup and don’t want to find the perfect one or who don’t want to change them in and out. Note, the All Cars (Baseline) FFB settings are simply the Certified HQ Cars FFB settings that I use as a baseline when starting to test any other car set. They just so happen to provide an acceptable FFB experience with most cars. I wouldn’t use it for everything but I can understand if some people prefer to just have one set of FFB settings.

Update 2018-02-11: Updated Force Feedback > Shovas Custom FFB Files for Original Cars bringing it to a Candidate quality level. Also added some methodology info for how I got about tuning FFB.

Update 2018-02-10: Updated Force Feedback > Shovas Custom FFB Files for Japan SGT300 Mod after some further work to get it to above average standard. Some of those Porsches feel really good, especially when you throw out the backend and feel it catch itself :)

Update 2018-02-10: Updated Force Feedback > Shovas Custom FFB Files for Super GT500 2005-2013 Mod and Japan SGT300 Mod after getting these to acceptable standards, although they still need work. Also added grades here to indicate how good the FFB for these cars feel. For example, HQ Cars have Grade A, or very good, FFB feel, EEC3 GT3 have Grade B, or acceptable/still needs work, FFB feel, and DTM Classics Mod has Grade C, or not really acceptable/needs work, FFB feel. I’ve added grades for each car set.

Update 2018-02-09: Noted my latest Field of View parameter, now 40.

Updated 2018-02-07: Updated Force Feedback > Shovas Custom FFB Files for Super GT500 2005-2013 Mod. I really enjoy seeing the FFB come into its own as you narrow in on the tuning. Feeling these cars come to life is an amazing experience. Sight and sound these cars are great and reviving the FFB brings the whole package together in a great experience.

Update 2018-02-30 – 2: Updated Mod Spotlight > EEC GT3 with some WIP thoughts. Added Getting Started > Community link and encourage taking advantage of the websites involved in the GTR2 community.

Update 2018-02-03: Added Force Feedback > Shovas Custom FFB Files including a table of FFB settings organized by Car Sets. Removed Force Feedback > My Personal Force Feedback Settings and Tweaking Notes as it was a little redundant after adding the Shovas Custom FFB Files section.

Update 2018-01-28: Added Mod Spotlight > Japan SGT300 Mod – Super GT GT300 Class Cars, Mod Spotlight > WSGT – World Super GT Mod (I’m impressed!).

Update 2018-01-27 -2: Added Troubleshooting > Crashes Loading Game, Mod Spotlight > Super GT500 2005-2013 Mod, Mod Spotlight > Subaru Impreza Mod, Mod Spotlight > FiaGT 2005 Mod, and minor edits to Mod Spotlight > DTM Classics Mod.

Update 2018-01-27: Added Peripherals > SimXperience AccuForce Direct Drive Wheel and TrackIR Head Tracking sections.

Update 2018-01-25: I’m a fan of Simracing Youtuber Jimmy Broadbent and he recently noticed my RaceDepartment post How much FFB can you feel in GTR2? 1/1000 of a percent (also a blog post of mine) and posted a video about his direct drive experience on GTR2 using the force feedback settings I recommended in that post: GTR 2 – How Does It Feel With A Direct Drive Wheel? Check it out, he seems to like it! I’m really happy to help some people get more enjoyment out of this oldie-but-goodie game.

Update 2018-01-25 – 2: Organized and cleaned up a lot of stuff in Getting Started, Mods and Force Feedback sections. There was a lot of clutter that I tried to weed out to make things more readable.

Update 2018-01-25 – 3: Posted my latest HQ Cars and Tracks “certified” UserData PLR and FFB tuning notes under Force Feedback > My Personal Force Feedback Tweaking Notes.

Update 2017-12-29: Added Known Issues > The Leader’s Advantage AI Bug.

Update 2017-12-08: CORRECTION: Time Acceleration is OKAY. Skipping qualifying sessions is a problem! Relevant notes about Time Acceleration updated.

Update 2017-12-02: Updated my latest personal UserData PLR file and my force feedback tuning notes under Force Feedback > My Personal Force Feedback Tweaking Notes. I’ve been experimenting going back to baseline ffb values and trying to reach a more iR/AMS/RF2 feel. I definitely prefer this in terms of drivability and reliability on the road.

Update 2017-11-10: Added Force Feedback > Guidelines for Tuning GTR2 Force Feedback. Updated Force Feedback > Rumble Strips Pushing/Pulling the Wrong Way to clarify wrong interpretation and now using default FFB parameter value.

Update 2017-11-09: Clarified Racing > Custom Daylight Acceleration works for regular race sessions but not 24 Hour races – they automatically time scale to race length setup when first starting the 24 Hour race.

Update 2017-11-08: Added Racing > Custom Daylight Acceleration. Added Resources > GTR Engineers Handbook and GTR2 Car-Owner’s Manual links. The GTR Engineers Handbook is particularly excellent for describe car setups better and more informatively than any in-game descriptions I’ve encountered before and the Q&A with real-life experts is also incredibly helpful.

Update 2017-10-31: Added Racing > How to Set AI Difficulty Level and Tips for Practicing and Qualifying for a Race sections. Also emphasized tip to avoid Time Acceleration as it causes a bug which results in overly quick AI lap times no matter what your AI difficulty level is set to.

Update 2017-10-29: Cleaned up and clarified Getting Started > Field of View. It’s now easy to understand and has an example. Fleshed out Force Feedback > My Personal Force Feedback Tweaking Notes with latest tuning adjustments.

Update 2017-10-12: Now using AI to AI Collision Rate=”40″ (max) as there’s no FPS loss for me so why not. Added Tips and Tricks > Avoid Time Acceleration to AVOID AI Bug Actually, skipping qualifying is the bug, Time Acceleration is fine.

Update 2017-09-22: Now using AI to AI Collision Rate=”32″ as I’m no longer experiencing FPS loss, maybe only stock tracks are affected and not HQ tracks. Try running HQ tracks if you have this problem. Added 5. Adding Friction and Damper under Force Feedback > My Personal Force Feedback Tweaking Notes. Added Force Feedback Settings under Getting Started > Modernizing as, while it may seem obvious, I wanted to highlight the need to do more than is available in-game to get closer to modern standards for FFB feeling. Added note about preferring HQ Cars and Tracks due to improved handling and grip adjustments in Getting Started > Modernizing > Mod: GTR2 HQ Mods Collection.

Update 2017-09-21: Added 4. Improving Corner Feeling under Force Feedback > My Personal Force Feedback Tweaking Notes.

Update 2017-09-17 – 2: HQ Cars & Tracks is working for me again after a fix. See comments under Modernizing > Mod: GTR2 HQ Mods Collection. Added Troubleshooting > Enable Tracing.

Update 2017-09-17: Added Troubleshooting section. Noted HQ Cars & Tracks was crashing for me. This works now, see comments under Modernizing > Mod: GTR2 HQ Mods Collection.

Update 2017-09-16: Added Tips & Tricks regarding turning up tire scrub and tire skid volumes and regarding refreshing old mod files if you’re experiencing instability.

Update 2017-09-15: Added Modernizing > 4GB Patch notes. Added GTR2 HQ CARS & TRACKS – 10th Anniversary and GTR2 HQ AI under Modernizing > Mod: GTR2 HQ Mods Collection. Added note that I’ve stopped using the Changing Weather Patch due to suspected instability.

Update 2017-09-14: Added Mod Spotlight > DTM Classics Mod with details for getting it running in 2017.

Update 2017-09-11: Detailed my FFB tuning in the section “My Personal Force Feedback Tweaking Notes”. Important! After a few rounds of FFB tuning I finally feel like I have a simple FFB setup that achieves car stability, quick response, and road feel. Added “GTR2 Crashes – It might Be Other Accelerated Graphics Apps” to the Tips and Tricks section.

Update 2017-09-08: Added “Disable Auto-pit and ai control” under the “Tips and Tricks” section. Noted tweaks in the “Make GTR2 Use More Cores For Better Performance” section under Performance. Added “My Personal Force Feedback Tweaking Notes” under the Force Feedback section.

Update 2017-09-06: Noted I’ve started over again from Julien Regnard’s FFB guide tuning FFB from baseline values instead of PLR defaults values under the “Helpful Guide for Advanced Force Feedback Tweaking” heading. Highly recommended. Don’t skip it like I did.

Update 2017-09-01 – 2: Added main section Performance and sub-section Make GTR2 Use More Cores For Better Performance to describe GTR2’s single-core use and how to get it to use more than a single core for better performance.

Update 2017-09-01: Added a Table of Contents for more convenient organization and to make it easier to find what you want.

Update 2017-08-30: Updated Force Feedback section to include more details on finding my optimal “FFB steer force average weight”, “FFB steer force exponent”, and “FFB rumble strip pull factor”. Also added “Force Feedback Tweaking Guide for Simbin Games by Julien Regnard” in Force Feedback section.

Update 2017-08-25: Added Changing Weather Patch mod under Modernizing section and added to Mod Spotlight. Updated my latest FFB settings in the Helpful Guide for Advanced Force Feedback Tweaking section.

Update 2017-08-20: Further FFB tweaking of “FFB steer force grip weight” which gives a feel of losing and gaining grip while cornering. Added Tips and Tricks section Use Auto-Clutch With Paddle Shifters. Added main section Mod Spotlight.

Update 2017-08-19 – 2: Added Getting Started sections: Mod: Track update for GTR2 Original Tracks, Mod: New GFX Mod, Field of View, Wheel Rotation and Wheel Lock, iRacing-like Brake Sensitivity for Potentiometer Pedals (eg. G27). Added Adding Game Cars, Tracks, Mods and More main section. Added Force Feedback main section with sub-section Helpful Guide for Advanced Force Feedback Tweaking.

Update 2017-08-19: Welcome to the initial posting of Secrets of GTR2! Check back from time to time as I add things and note the updates in this update box.

### What is GTR2?

From the Wikipedia entry,

GTR 2 – FIA GT Racing Game is a sports car racing simulator developed by Blimey! Games and SimBin Studios (later Sector3 Studios) for the x86 PC and is a sequel to GTR. Since its release in September 2006, it has received widespread acclaim. The game simulates the 2003 and 2004 FIA GT Championship racing series.

And here’s the official game trailer,