Add Elite Dangerous Support to RenoDX

[mqhaji]

This pull request integrates Elite Dangerous with RenoDX by editing the original tonemapper shaders and upgrading the game to scRGB HDR. Users can choose among Vanilla, None, ACES, or RenoDRT tonemappers, with all color math performed in rgba16 and linearized by the user set inverse EOTF (gamma 2.2 or sRGB).

Changes

1. Dual-Pass Tonemapping

   • Tonemaps once to SDR and applies LUT.
   • Separately tonemaps to user set HDR peak brightness.
   • Uses UpgradeToneMap to ensure SDR LUT affects HDR color, so no separate “HDR-only” LUT is needed.

2. Custom Tonemappers with adjustable sliders

   • Tone Map Type: Vanilla, None, ACES, RenoDRT
   • RenoDRT has been pre-graded to closely match the vanilla tonemapper, this was done with Diffuse White at 203 nits and Peak White at 1000 nits.
   • Tone Mapping: Peak Brightness, Game Brightness, UI Brightness, Gamma Correction, and Hue Correction.
   • Color Grading: Exposure, Highlights, Shadows, Contrast, Saturation, Highlight Saturation, Blowout, Flare, and Restoration Method (Luminance vs. Per Channel).
   • Scaling (ToneMapScaling): Luminance or Per-Channel.
   • LUT Strength: Controls the percentage at which a LUT is blended in.

3. EOTF Selection

   • Configurable gamma 2.2 or sRGB for the inverse EOTF.

4. Single-Pass Linearization

   • All linearization occurs in a final pass over the entire image.
   • This preserves the game’s original gamma-space blending for scene and UI elements, avoiding unintended changes to transparent overlays.

5. scRGB and Render Target Upgrades

   • Explicitly enables 16-bit float (r16g16b16a16_float) upgrades for certain 8-bit formats matching the screen’s aspect ratio, required for ensuring textures upgrade to HDR successfully when supersampling is enabled.

By merging this, Elite Dangerous gains support for HDR and advanced tonemappers.