REX Simulations is closing out the year with a critical patch for their flagship Microsoft Flight Simulator 2024 utility: REX Atmos Core – Technical Update 1.0.
While “Technical Update” might sound a bit dry, this is an essential download for anyone using the software. It addresses crucial compatibility issues with MSFS 2024’s latest major build (SU4) and irons out several frustrating bugs regarding weather rendering and UI functionality.
What is REX Atmos Core?
Microsoft Flight Simulator 2024 is already stunning, but REX Atmos Core is made for the simmer who wants complete control over how that stunning world looks.
At its heart, REX Atmos Core is an atmospheric engine and visual enhancement utility. It gives users granular command over the environmental lighting, haze, sky colors, and overall mood of the simulator.
Whether you are trying to replicate a hyper-realistic, hazy summer afternoon or create a dramatic, cinematic sunrise for screenshots, Atmos Core provides the sliders and presets to make the simulator look exactly how you want it to. It’s not the most user-friendly utility (REX could make some improvements there), but with some patience and a little help from the community, the results can be stunning.
Technical Update 1.0: The Highlights
This latest release focuses heavily on stability and ensuring the software plays nicely with the rapidly evolving MSFS 2024 platform. The most significant line item in the changelog is full compatibility with Microsoft Flight Simulator 2024 Sim Update 4. But there are other changes, as listed by REX in the changelog:
FIX LIST:
- FIXED – Full compatibility with Microsoft Flight Simulator 2024 SU4.
Resolved multiple integration points affected by SU4, including environmental data offsets, and API handshake behavior to ensure stable communication. - FIXED – Custom weather rendering in METAR Mode.
Addressed issues in the METAR parsing pipeline, including interpolation logic and fallback handling, preventing incomplete or partial scene generation. - FIXED – Custom weather rendering in Simple Mode.
Corrected slider-based parameter translation and rendering callbacks. - FIXED – Custom weather rendering in Advanced Mode.
Rebuilt several internal hooks responsible for multi-layer atmospheric rendering, improving fidelity and proper synchronization between volumetric clouds, and lighting. - FIXED – Required description field preventing preset saving and edit function.
Adjusted UI rules to allow preset persistence without unnecessary conditions. - FIXED – UI validation preventing the Save button from enabling.
Resolved conditional flag errors that interfered with save-state logic. - FIXED – GetLocalSettingsRead() not reading local settings.json.
Repaired the file read routine, corrected its directory resolution, and improved JSON parsing, ensuring user preferences load correctly at startup. - FIXED – Spelling correction of “Enviro” in the save dialog box.
Corrected text label.
ENHANCEMENTS:
- ADDED – Startup Log System for application process verification.
Integrated a multi-stage logging pipeline that records initialization events, module load order, environment checks, and error flags. - ADDED – Simulator Runtime Validation.
Implemented a detection function to confirm whether Microsoft Flight Simulator is actively running. This ensures correct sequencing, prevents null-reference operations, and delivers safer startup behavior.
CRITICAL Installation Instructions: Do Not Overwrite!
REX Simulations has issued a strong warning regarding installation. Because this is significant code change, you MUST uninstall all previous versions of REX Atmos Core before installing Technical Update 1.0.
Do not simply run the new installer over the old one. Follow these steps:
- Completely uninstall any previous version of REX Atmos Core via your Windows settings.
- Manually check for and remove any leftover install folders to ensure a clean slate.
- Download the new installer
- Run the new
.exeor.msito install the fresh build.
