"Throttled LOD"
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When sectors are too tight, the detail too sporadic and the effect of LOD becomes strained and restless, we call this being "throttled" and it actually begins to have a negative impact on performance. The balance between the amount of detail that can be saved and the impact of swapping geometry in and out of the vertex buffer can be off so much that it becomes better without it all. This happens between stages, so perhaps lower stages are fine but the higher stages are problematic, or vise-versa. The easy solution is to simply skip those stages and we can even automate that, but the by-product is more pop-in and lower framerates, a bad combination.
Therefore, sectors must be proportioned and arrayed in such a way that it doesn't just consider detail, speed, view and relevance, but also the sum of all these aspects and the estimated performance. Having huge sectors is not the answer. Sectors should be what they need to be, down to 512 cubic units, which is roughly 8 metres cubed. This is for claustrophobic indoor corridors ala Doom3, and in rare circumstances even 256 can be tried, for areas dedicated to cinematics. A sprawling outdoor environment such as GTA demands larger sectors, perhaps 1024 or 2048, or even more, if for something like a bridge or tunnel. These numbers may halve in the near future, but the principle is only compacting, not changing. Trying to use 512, especially purely in an attempt to squeeze more triangles into the higher stages, is not a wise decision and throttling will easily occur, depending on the geometry in the sector. A master mapper can do this, but it's always a challenge of balance and compromise. If too many sectors are throttling themselves, at some point, it defeats the whole purpose of itself, no performance is gained and our whole workflow no longer fully being utilised as intended.
The solution to this problem is almost always "articulation", as the problem stems from geometry that can't be easily or automatically degraded to lower polycounts, and this geometry is typically always sporadic and shallow. A good description of potential problems might be too "bitwise" or too "piecemeal", when too many separate objects are Frankensteined together to create something that should be more wholesome, more technically manageable, and constructed more professionally. We're not talking about vegetation or effects because those are treated as volumes and can physically scale to offset lesser population, but something that presents the same such issues but without the same scalable foundation to counter.
Half of good articulation is baking, and baking anything for the sake of fixing throttling is perfectly acceptable, especially because the assets won't require high resolution textures or even full materials, even if it's so unique to only have a single instance for a simple fix. Framerates are that important. If articulation isn't the answer, it's almost impossible to imagine what it would be, but easy to imagine it's just poorly designed, and with no skill to articulate.
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