Curve Controller - Real-Time Gamepad Joystick Response Curves

Change how your left stick, right stick, or both respond on Windows, with instant presets, distance-from-center response by default, optional separate X/Y response and a ten-point custom curve editor. Native C++17, a compact interface, and low-level remapping through the Interceptor Gamepad & Controller kernel filter driver.

Download | Driver setup | Build from source | JSON examples

The screenshot is an explicitly simulated preview, not a physical-device test.

Install and start

1. Download the Windows x64 ZIP from Releases and extract all files. It includes CurveController.exe and the matching Gamepad & Controller InterceptorSetup.exe (signed driver 1.0.13.0).
2. Connect your controllers and close other capture/remapping apps. Run InterceptorSetup.exe, accept elevation and click Install / reinstall. If the combined Interceptor edition is installed, uninstall it first.
3. If setup requests it, use Windows Restart, then reopen InterceptorSetup.exe to finish pending device associations. Follow any further restart request until setup reports that the driver is running and its API responds.
4. Open CurveController.exe and accept elevation. It checks the driver before starting capture. If the driver is absent or unavailable, a dialog offers Open driver setup or Continue without driver.
5. Check Left joystick, Right joystick, or both, and choose a preset. Distance from center is selected by default; X / Y separately is also available. Changes are immediate, including when a previously observed stick is held still.

There is no Apply button. Unchecked sticks, buttons, triggers, hats and other unedited report fields retain their physical values. Settings affect all compatible captured controllers; the device menu selects only the live preview. Closing the app releases capture and restores physical passthrough. A failed connection is retried automatically; Reconnect is also available.

Driver setup opens the verified installer beside the app; opening the app never installs a driver silently. The same InterceptorSetup.exe is a separate release download. If you choose only the standalone app EXE, put this setup beside it; otherwise Driver setup opens the driver download in your browser. An altered installer or another edition is rejected by its SHA-256 hash. After setup finishes without a restart, choose Reconnect or reopen the app. Without the driver you can still edit curves and import/export settings; physical input remapping needs the installed driver. Remove the driver.

Find your response

Choose Linear, three exponential curves, three inverse curves, Smooth S, Smoother S, Ease out, Precision, or Early max. The graph plots the actual response function, from physical distance on the horizontal axis to output distance on the vertical axis, both from 0 to 100%.

• Linear preserves the original stick values exactly.
• Exponential gives finer control near the center; inverse exponential boosts small movements. The quadratic/square-root and cubic/cube-root pairs are inverses.
• Precision includes a 10% inner deadzone. Early max reaches 100% at 80% input.
• Custom provides ten movable points, plus fixed 0/0 and 100/100 anchors. Click a point and drag it, type its Input/Output percentages, or use arrow keys (Shift for smaller steps). Points cannot cross horizontally.

For 10% distance from center -> 50% distance, select Custom, choose the first point, and enter Input 10, Output 50. The smooth, shape-preserving custom curve passes through the editable points and stays within the output range. Custom curves can deliberately be non-monotone.

Distance from center transforms the length of the X/Y stick vector while preserving its direction. For example, physical X=6%, Y=8% is 10% from center; with the custom 10% -> 50% point it becomes X=30%, Y=40%, still pointing in the same direction. Both modes update immediately, including a held stick.

Choose X / Y separately to apply the curve independently to each component, using the absolute X/Y values on the graph and preserving their signs. Mode selection is saved automatically and included in JSON exports. Older settings without an explicit mode use the new distance-from-center default.

Distance is Euclidean: sqrt(X*X + Y*Y), with 100% equal to full deflection along one axis. Some square-gate devices can report diagonal lengths above 100%; those outer values are preserved and displayed at 100% on the graph. Linear remains exactly unchanged. Inverse curves can compensate a matching response curve in a game; other game processing may still affect the final feel.

Save, export and share

Preferences save automatically in your Windows registry at HKCU\Software\TitanCSA\CurveController. No settings file is created beside the application or in your documents. The last custom points are retained when you try other presets. Uninstalling the driver does not remove these app preferences.

Export JSON saves an explicit, portable settings file; Import JSON validates and immediately loads one. Nothing is executed from JSON. The Examples folder contains linear, exponential, inverse, left-only, right-only, custom 10% -> 50% and separate-X/Y examples. JSON format.

Compatibility and live values

Works with supported HID, XInput/XUSB, XInputHID and USB GIP controller paths, including compatible DS4/DualShock 4, DualSense, wired Xbox 360 and Xbox One/Series profiles supported by the driver. It edits the existing physical input path; it does not create a virtual gamepad or send keyboard/mouse events.

HID axes are decoded from their descriptor. Automatic mapping uses X/Y and a common Z/Rz or Rx/Ry right-stick pair; use HID stick layout for ambiguous descriptors. Unknown/proprietary controls are not guessed. Multiple report IDs and repeated matching stick usages are retained; the four preview values show the most recently observed matching component.

The live panel shows received physical values and the representable transformed values accepted for forwarding by the driver. It is not an independent measurement that a particular game consumed the report. No input yet is shown as --. The graph's live markers have small X and Y labels in the same color as their joystick's points in separate-X/Y mode. Distance mode shows one Center marker per stick and a Center IN/OUT row. A Center marker appears only after both physical components of an unambiguous stick pair are known. Split HID reports use the latest observed physical counterpart and refresh the coupled output; missing or ambiguous pairs pass through until a valid pair is available. Windows, device firmware, connection type and game processing still affect delivery.

The capture loop is event driven: no FPS cap, fixed sleep or UI animation delay is inserted in report processing. UI highlights animate separately; measured stick values are displayed directly. This is not a claim of zero latency or compatibility with every device. Validation scope.

Driver demo and project status

This is an example of using Interceptor Gamepad & Controller and its C++ SDK. The app source is MIT licensed. Driver source is not included; its binaries have separate terms.

The driver's demo allowance is shared across applications of that edition and starts when capture or controller monitoring begins. Closing or reinstalling does not renew it. At expiry, remapping stops and physical input passes through; use Windows Restart for a new allowance. Install the current Microsoft-signed one-hour driver package (kernel 1.0.13.0). Restart Windows after upgrading from an older demo clock. Curve Controller uses the installed driver's actual policy. For the unrestricted driver, DM titancsa on Discord.

Inspired by GamePad Remapper, a more complete scripting/macro example for the same driver. Interceptor independently evolves the workflow popularized by oblitum/Interception; these projects are not affiliated with oblitum and are not ABI-compatible with that original API.

Intended use and responsibility

Created for legitimate customization, accessibility, development and testing. You are responsible for your use of the application, driver and SDK, including compliance with applicable law and software/service rules. The author does not authorize unlawful use and disclaims warranties and liability to the extent permitted by applicable law. See LICENSE; nothing here excludes rights or liability that cannot legally be excluded.