Graphics Enhancement: Extended draw distance, improved particle visibility, and PBR terrain shaders

[bwiemz]

Is your feature request related to a problem?

Supreme Commander: Forged Alliance's visual quality is capped by conservative LOD cutoffs, limited particle visibility ranges, and disabled advanced terrain shaders. On modern hardware, players can afford significantly higher draw distances and richer visual effects without performance concerns, but the current options don't expose this.

Specifically:

• Draw distance: The "Extreme" LOD setting uses cam_SetLOD 0.70, which extends draw distance by only ~43% over "High". Units and props pop in/out visibly at moderate zoom levels.
• Particle effects: Most emitters have LODCutoff values of 100-300, causing explosions and weapon effects to disappear at relatively close camera distances. 325 emitters are disabled on Low fidelity, hiding important gameplay feedback like weapon impacts and shield effects.
• Terrain rendering: Advanced PBR terrain techniques (TerrainPBR, TerrainPBRNormals) with rotated texture sampling, height-based splatting, and triplanar cliff projection are fully implemented in terrain.fx but commented out and unavailable to mappers.
• Shadows: Shadow render distance caps at 440 and resolution at 2048, both lower than modern hardware can comfortably handle.

Describe the solution you'd like

1. Extended Draw Distance

• Add an "Ultra+" Level of Detail option with cam_SetLOD 0.50 (2x draw distance vs High, up from 1.43x for Extreme)
• Increase unit LOD coefficient from 0.7 to 1.0 in blueprints-lod.lua (~43% unit draw distance increase)
• Increase prop LOD multiplier from 180 to 260 and tree LOD caps from 640 to 900 in blueprints-props.lua
• Increase shadow render distance slider max to 600 and shadow resolution max to 4096

2. Improved Particle Visibility

• Batch-increase emitter LODCutoff values: 1.5x for values ≤150, 1.25x for values 151-500
• Selectively enable important gameplay particles (explosions, weapon impacts, shields) on Low fidelity

3. PBR Terrain Shaders

• Uncomment the TerrainPBR and TerrainPBRNormals techniques in terrain.fx, making them available to mappers via the terrain shader dropdown. No existing maps are affected — they keep their current technique.

Describe alternatives you've considered

• Engine-level FIDELITY_ULTRA (0x03): Would require binary patches to support a 4th fidelity tier. Too invasive for the benefit; the existing High fidelity already uses full PBR for units.
• Doubling all LODCutoff values uniformly: Too aggressive — breaks the relative priority hierarchy between small and large effects. The tiered multiplier approach (1.5x for close-range, 1.25x for mid-range, unchanged for long-range) preserves design intent.
• Making all particles visible on Low fidelity: Would hurt performance on low-end hardware. Selective enablement for gameplay-critical effects is a better balance.

[Garanas]

I'm afraid that some features that you request will not work out the way you expect them to.

Supreme Commander: Forged Alliance only has two CPU threads to utilize: one for the simulation and one for the UI (rendering, etc). Unfortunately, a lot of (related) rendering logic happens on the CPU. This was great in 2006, but single core performance did not scale the same way that CPUs and GPUs did in the past 20 years.

As a few examples:

• Pushing the camera lod value even further can create visual artifacts where the map as a whole just stops to render. This appears to be related to tessellation, I'm not sure what triggers it. Some maps fall prey to this sooner than others.
• Batching is done on the CPU, the more (broken) tree (groups) there are, the longer it takes. Increasing the LOD flat out as you suggest may cause a significant bump in the frame rate on some maps.
• Previously the shadow LOD was made infinite (which is what 600 is not far from for some maps), and this hindered performance significantly - it could double the time it took to render a frame. Even on high end hardware the framerate could dip below 60fps.
• Particles are created in the simulation thread. This appears to be very, very expensive. Once particles exist it is fine, but Supreme Commander re-computes particles when you zoom into something. As a result there can be significant hiccups in performance, up to the point where the simulation has to halt for a bit. This is why particles have a relative short lifespan in comparison to the Steam version of the game.

[hotcheese4444]

@bwiemz perhaps, set this options, in your game. And make a comparison video of the visual difference and performance differences.