Track spline points and performance

[valbridge]

Beginning to notice a lot of 'jerkiness' in driver, even with settings at lowest levels. Especially where junctions are laid.
This makes me wonder whether track spline points adversely affect the smooth running of consists when in driver mode. Now being better versed in performance analysing by checking assets in the explorer window, have replaced a number of buildings whose LOD was excessive [according to the tutorial on the topic]. Now wonder at track spline point interference!

Any thoughts or suggestions would be welcomed. Please don't suggest upgrading my pc...it's fine.

Thanks in anticipation.

 

[pware]

This is an often debated topic in these forums. From what I have gleaned from the tech-talk in the discussions is that non-spline objects are handled directly by the GPU while splines tend to be "shuttled" back-and-forth between the GPU and the CPU during the rendering process - this, apparently, is the main cause (or one cause) of the performance hit.

I am currently renovating an old TRS2006 route of mine to TANE/TRS19 standards and as part of that process, I am eliminating as many splines as possible. Old TRS2006 era house and building splines have been replaced by actual houses and buildings. Dirt road splines (which I never liked anyway) have been replaced by suitable dirt textures which, IMHO, do look better. Some essential splines, such as fencing and bitumen roads, that originally trailed off to infinity have been truncated and their endings hidden with foliage.

The resulting reduction in the CDP file size for the route has been significant and that must have a beneficial effect on performance.

Some splines, such as fences and power lines, are essential for the scenery and cannot be replaced. And of course, the track itself has to remain. But, as I have noted, there is still much that can be done to improve performance.

 

[JCitron]

It depends upon the assets with some performing better than others. Grass splines, depending upon the era and creator, can really, really take a toll on performance due to how they're constructed with the double-sided faces and sometimes high resolution textures to go with them. I have found there are some fences, telegraph, roads, and power poles too that drag things right down.

These aren't the only things. Some tracks, such as the 132 lb. Jointed rail MRT or whatever it's called, for example, is notorious for poor performance. The track was poorly constructed to begin with with way more polygons than is necessary and there are variants based on that track. So if you're using that track, try something else. Some of the pro-track are a bit heavy as well I have found.

Like other assets, you need to pick through and find which ones work best for you. The problem is some assets look beautiful, but they are over done and the beauty comes with a high cost in performance and sometimes we need to compromise.

 

[valbridge]

Thank you John and Pierre for your feedback,
The track I am using is <kuid:359841:101582> DMT Pro TRACK V2, Third Rail Left, Concrete Sleepers, Dark Brown Ballast with its associated third rail junction track for the Brighton Line route being constructed. As its a third rail route this was the best I could find, unless someone knows of a better one. Rarely do I use grass splines as textures, in my view, do as good a job. Although I had to replace this texture <kuid2:72938:21123:1> UltraTexture - Spring Grass 04 - Seasonal/Full Snow as it was eating up performance, pity really its a lovely texture.

Liked your idea Pierre re texture replacing dirt roads...works fine.

Gradually going through all assets and eliminating/replacing heavy ones with something similar but with less of an impact on performance, a bit laborious. Yes, having that attractive look about a route does come at a cost. My attitude is changing in that regard to a more pragmatic one.

Altering route layout with fewer spline points now a necessity . Feels like I am starting over! Just when you think things are looking good, this happens.
Cheers,
Val.