RDR 2: Hidden system.xml Command for Advanced Water Physics Test

The objective is to bypass the standard “1/6” or “Half” presets and force a $1.0$ (Ultra) value across all water-related sub-systems, including the hidden deepsurfaceQuality flag.

Contents hide

1 1. Locating the system.xml

2 2. The “Advanced Physics” Overrides

3 3. The “Deep Surface” Quality Fix

4 4. Hardware Warning: The “RIP FPS” Factor

1. Locating the system.xml

The configuration file is stored in your user documents folder, separate from the game’s installation directory.

File Path:

Documents\Rockstar Games\Red Dead Redemption 2\Settings\system.xml

2. The “Advanced Physics” Overrides

Open the system.xml with a text editor (Notepad++ is recommended). You need to find and modify the following specific lines within the <video> or <advancedGraphics> sections.

XML Command	Recommended Value	Technical Purpose
`waterMouseWheelScale`	`1.000000`	Internally linked to the physics step rate ($dt$) for fluid simulation.
`waterReflectionResY`	`1024` or `2048`	Increases the resolution of objects reflected in the physics-active water.
`deepsurfaceQuality`	`kSettingLevel_Ultra`	Hidden Flag: Fixes the “pudding” look of mud and deep water interaction.
`waterPhysics`	`4`	Forces the “Advanced” mode beyond the standard slider’s range.

3. The “Deep Surface” Quality Fix

One of the most impactful “hidden” commands is deepsurfaceQuality. In the standard UI, this is often set to High even on Ultra presets.

The Manual Fix: Change <deepsurfaceQuality>kSettingLevel_High</deepsurfaceQuality> to <deepsurfaceQuality>kSettingLevel_Ultra</deepsurfaceQuality>.
The Result: This enables high-precision tessellation for mud, snow, and waterbeds, allowing for more realistic “deformation” when Arthur or his horse moves through them.

4. Hardware Warning: The “RIP FPS” Factor

The advanced water physics test is one of the most CPU-intensive tasks in RDR2.

CPU Bottleneck: When set to the maximum manual value, the game engine calculates hundreds of additional “ripple points.” Even on an RTX 5090 or RX 8900, you may see a 20-30% drop in FPS near large bodies of water (like Flat Iron Lake) because the CPU cannot keep up with the physics draw calls ($DC_{phys}$).
Sync Issues: If you notice the water looking “thick” or like “melted cheese,” ensure your waterRefractionQuality is set to High to match the physics displacement.