The Problem With GIANTS Engine in 2026

This issue was finally brought up on Farming Simulator’s Discord channel. And I don’t know how many times I’ve run into this problem while working on the Zielonka City map…Too often.

Now I’ve seen some things during this map project about how snow/wetness/rain effects are displayed on map assets. At the same time, I mainly use the placeables shader rather than the building shader for simplicity and “lazy modding”.
The shader (or, let’s call it a debugger) that checks how wetness is displayed on an asset is the debugShader.xml.

When this shader is applied to a material in GIANTS Editor, we can select the wetnessDebug variation (as shown in the XML code below). This will display a green layer where wetness will be successfully added, and a red layer where it will not.
The thing is, this debugger is just giving “false messages” because I’ve seen assets after loading my map in Farming Simulator where the wetness under rainy conditions adds a weird, dark layer to the asset’s surface, EVEN when the debugger was painting the surface green.

The main problem with GIANTS Engine/Farming Simulator 25 in 2026, after all the patches and updates in 2025, is that rain and snow effects get applied to almost any asset that is placed within a modded map, unless it’s under a collision surface that blocks wetness/snow. And we are now talking about assets not made by GIANTS Software, but assets made by the modder. This happens even to assets that don’t have any shader applied to the material properties.

Usually, bad UVs can cause shader issues, but not always.
If the material has a normal map, it will show bad UVs if it’s not a smooth normal map. This is also quite noticeable in Blender.
The other one that will visualise bad UVs is the specular/gloss map.
But even if we make a great-looking UV map for our asset, the rain/snow layer effect may still appear weird. And this is noticeable on vertical walls and surfaces. Even so, on flat road surfaces.

The other main problem is how terrain decals with alpha maps (variation alphaMap) get ignored by the GIANTS Engine when setting wetnessScale and wetShininess. What happens is that even if the values for these two are set close to zero, GIANTS Engine are making these terrain decals look glassy. They appear as terrain decals with excessive wetness.
We may even add negative values, and the final result is the same.

Terrain decals appear silver under rainy conditions in FS25 when using the alphaMap variation. And yes, the game engine ignores wetness properties even when the value is set to zero.

Work-Around (Temporary Solution)

To address wetness on terrain decals, I removed the specular map entirely. This means loss of visual effects for the asset itself (when it doesn’t rain), and the material will also appear darker.

Wetness Artefacts Found in Kinlaig (FS25 Highlands DLC)

As discussed at the beginning of this article, the texture issue occurs when map assets get wet, meaning wetness is applied to the asset during rainy weather conditions in FS25.

These screenshots are from assets made by GIANTS Software for the popular Kinlaig DLC map.

Underneath the railroad bridge in Kinlaig, we’ll find this metallic/rusty surface, with visible raindrops on the upper part of the steel beam, while the lower part is dry. And usually there’s a noticeable line between them that creates this visual artefact. This steel beam, or parts of the railway bridge itself, is probably using the building shader, since it has a dirt layer.

This wooden fence has some noticeable lines, where the upper part is wet.

These dumpsters also have lines. The upper part is wet, and the lower part is dry. There’s no smooth transition between.

Same thing with this wooden shed. There are stretched UVs between the planks.

These two containers have a very visible line that runs around the entire asset.