fs25-texture-guide - SKILL.md Agent Skill

name: fs25-texture-guide description: Use when working with FS25 textures, DDS formats, normal maps, specular maps, texture naming conventions, or resolution guidelines.

FS25 Texture Guide

Overview

Texture conventions and formats for FS25 modding. GIANTS Engine uses DDS textures with specific format requirements.

When to Use

Creating or converting textures for a mod
Choosing the right DDS format
Setting up material textures (diffuse, normal, specular)
Debugging texture issues (pink/missing textures)

DDS Formats

Texture Type	Format	Suffix	Notes
Diffuse/Albedo	BC1 (DXT1) or BC3 (DXT5)	`_diffuse`	BC3 if alpha needed
Normal map	BC5 (ATI2/3Dc)	`_normal`	2-channel (RG), NOT BC1
Specular/Gloss	BC1 (DXT1) or BC3 (DXT5)	`_specular`	R=specular, A=gloss (if BC3)
Mask/Alpha	BC4 (ATI1)	varies	Single channel

Important: Normal maps MUST be BC5. Using BC1/DXT1 for normals causes visible banding artifacts.

Naming Conventions

myVehicle_diffuse.dds
myVehicle_normal.dds
myVehicle_specular.dds
myVehicle_vmask.dds         # vehicle color mask
myVehicle_dirt.dds           # dirt overlay

Base game patterns:

store_ prefix for shop images
_ao suffix for ambient occlusion
_vmask for vehicle color mask (paintable areas)

Resolution Guidelines

Asset Type	Typical Resolution
Large vehicle	2048×2048 or 4096×4096
Small implement	1024×1024 or 2048×2048
Placeable building	2048×2048
UI icon / store image	256×256 or 512×512
Terrain layer	1024×1024 (tiling)

Always use power-of-two dimensions (256, 512, 1024, 2048, 4096)
Generate mipmaps for all 3D textures
Store images do NOT need mipmaps

Material Setup in I3D

<Material name="vehicleMat" materialId="1"
          customShaderId="2" customShaderVariation="colorMask">
    <Texture fileId="1" />        <!-- _diffuse.dds -->
    <Normalmap fileId="2" />      <!-- _normal.dds -->
    <Glossmap fileId="3" />       <!-- _specular.dds -->
</Material>

Shader Variations

Variation	Use Case
`default`	Standard opaque material
`colorMask`	Paintable vehicle (uses vmask)
`alphaTest`	Cutout transparency (foliage, fences)
`alphaBlend`	Smooth transparency (glass)
`mirror`	Reflective surfaces

Color Mask (Vehicle Painting)

The _vmask.dds texture controls which areas are paintable:

R channel: Primary color area
G channel: Secondary color area (if supported)
B channel: Tertiary / detail area
White = fully paintable, Black = not paintable

Common Issues

Problem	Cause	Fix
Pink/magenta texture	Missing or wrong file path	Check `<Files>` paths in I3D
Blurry at distance	Missing mipmaps	Regenerate DDS with mipmaps
Normal map looks flat	Wrong format (BC1 instead of BC5)	Re-export as BC5
Shiny/dark patches	Wrong specular format	Check specular is proper format
Texture seams	UV island padding too small	Add 4-8px padding between UV islands

Tools

GIANTS Editor: Built-in texture preview and material editing
Paint.NET / GIMP: With DDS plugin for texture creation
texconv (DirectXTex): Command-line DDS conversion
Compressonator (AMD): DDS compression with preview