RenoDX - HDR

Rewrite the graphics pipeline to fix bugs in HDR gamma, saturation and tone mapping processing, restoring original artistic visuals

RenoDX - HDR Repair - Tone Mapping - Resident Evil 4 Gamma Adjustment

🎮 **About this mod**

This mod utilizes the ReShade add-on system to simplify the update process and avoid directly modifying game files. The source code has been made public on GitHub for users interested in understanding the inner workings or contributing to future improvements.

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🎨 Original HDR problem

• **Broken Tone Mapping**: The default tone mapping does not take into account user brightness settings, causing peak whites to appear over or under exposed depending on how high or low the paper white slider (the second slider in the calibration menu) is set
• **Bad LUT Sampling**: The game uses an sRGB LUT that only accepts SDR input. To make HDR work, the developers created a piecewise function that compresses all highlights back into the SDR range and then multiplies them up. This results in lost highlight detail and corrupted gradients
• **Gamma/Contrast Boost**: The developer added a gamma/contrast boost to the image that does not exist in SDR. This boost seems to be a misguided attempt to fix broken gamma in HDR

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✨ Solution

• **Refined Tone Mapping**: Implements Vanilla+ tone mapper, corrects peak white levels, removes unnecessary saturation and gamma boost
• **Enhanced HDR LUT Sampling**: Highlights are now correctly tone mapped to SDR, using a new function to calculate the color change of the LUT, which is then applied to the original HDR color. Gradients have been fixed, colors are more vibrant, and false hue shifts have been eliminated
• **True to the original visuals**: Uses the same tone mapper toe parameter values ​​as SDR by default, producing a more balanced image while preserving HDR highlights. sRGB → 2.2 gamma correction has now been applied, matching the look developers may expect for their games
• **Enhanced User Control**: Introducing interactive sliders that allow players to customize the visual experience to their liking, ensuring a more balanced and visually pleasing HDR presentation

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⚙️ ReShade UI options

In the ReShade UI you will find the RenoDX window with the following options to customize your HDR experience:

• **Tone mapping type**: including Vanilla, Vanilla+ and other options
• **LUT Strength and Scaling**: Allows full range color grading without clamping. Scaling only works with LUTs with boosted black levels
• **Internal Sampling**: Control whether to use vanilla or enhanced LUT sampling
• **Highlight Contrast, Shadow Toe, Gamma Adjustment**: Detailed controls for fine-tuning HDR output

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📥 Installation Guide

• Install ReShade 6.3.3 or higher, which supports add-ons. No ReShade effect required
• Copy the module file to the "Resident Evil 4" installation folder, adjacent to the game exe file
• Run the game and use the keys to access the ReShade UI to adjust HDR settings

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👥 About the author

Join the #renodx channel on the HDR Den Discord to join the discussion and discover more mods.

🙏 Thanks

• Thanks to ShortFuse for developing the RenoDX framework
• Thanks to Pumbo for providing the DICE tonemapper code
• Thanks to Lilium for making the HDR analysis tool I used extensively when creating this mod
• Thanks to Iorek and KoKlusz for help with testing

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🌟 **Experience Suggestion**: It is recommended to use this module in a bright environment to obtain the best HDR visual effect. When adjusting settings, you can fine-tune each parameter step by step to find the configuration that best suits your display device and visual preferences!