Materials and Textures

There are two rendering modes on Sketchfab: Classic and PBR (Physically Based Rendering). By default, uploads are set to PBR mode. This is almost always the best choice. It provides more realistic material and lighting, and does not prevent anything that could be done in a Classic workflow.

Materials

Sketchfab supports multiple materials and objects in your scene. Give each material a unique name because the 3D editor merges objects by material name. Avoid special characters when naming.

If possible, you should join every mesh that uses a material because it helps performance.

When uploading the Wavefront (.OBJ) format, the material library file (.MTL) should be included.

Sketchfab 3D model editor multiple materials

Colors

If you are not using texture images, you can choose a color for any slot from the color picker.

Sketchfab 3d model settings material color picker

See also Vertex Colors.

Textures

Textures are images mapped to the surface of your model. For details on shaders/texture slots, see Materials (PBR).

Importing

Upload textures with your model file or embed textures in the model file (e.g. .BLEND, .FBX). You can put image files in the same folder/directory as the model file, or a sub folder/directory. If your textures are properly referenced by the model file or use our naming conventions, they will be automatically applied to your model.

When using the Wavefront (.OBJ) format, the material library file (.MTL) is required to define materials and reference their textures.

If you need to add textures after uploading, you can use the texture manager or drag and drop images into their slots in the material editor.

Sketchfab 3d model material import texture

Sketchfab 3d model material texture settings

Sketchfab 3d model material texture settings

Supported Formats

During upload:

  • .JPG
  • .PNG
  • .TIFF
  • .TGA
  • .DDS
  • .GIF
  • .BMP
  • .VTF
Anything that is not .JPG or .PNG is converted to .PNG.

In 3D Settings:

  • .JPG
  • .PNG
  • .TGA
.TGA is converted to .PNG.

Filtering

There are three options for texture filtering.

  • Trilinear: Usually the best choice, especially for large textures.
  • Bilinear: Uses less memory than Trilinear, but is slower.
  • Nearest: Very fast rendering, but individual pixels will be visible.
Bilinear can be useful for hiding texture seams.
Nearest can be useful for pixel-art/voxel textures.

Color Formats

Depending on the shader slot you're working with, you'll see different color encoding options under Format:

  • RGB: Red, Green, and Blue color channels
  • Alpha: Alpha transparency channel only
  • Luminance: R channel only

By choosing the appropriate format, texture opacity can be encoded either as an alpha mask or by grayscale levels.

Color Space

Sketchfab supports sRGB and Linear RGB colorspaces for textures. You can switch between them in the Material Editor's Manage Textures dialog. If you're unsure, Auto is the best choice.

Sketchfab 3d model material texture settings colorspace

UV Channels

If you have more than one UV channel on a single material, you will see an additional interface option to switch between them.

Sketchfab 3D model editor texture UV channels

UV Offset and Tiling

UV Offset and Tiling are not currently supported.

Texture Wrap Modes

Texture UV coordinates (u, v) map to surface ST coordinates (s, t). UV coordinate values can only range from (0, 0) to (1, 1), so there are several ways to wrap a surface with a texture. Mapping options can be changed with Wrap S and Wrap T:

  • Repeat: The texture is tiled (2.6 → 0.6)
  • Mirror: The texture is mirrored (1.2 → 0.8)
  • Clamp: Texture pixels outside the [0, 1] range will be clamped to the border of the texture

Sketchfab 3D model editor texture UV channels S/T wrap repeat mirror clamp

Processing & Compression

Textures are compressed to minimize model download times. We convert any image that is not .JPG or .PNG to .PNG. Then, we generate compressed versions of every texture. The format and level of compression depends on the image attributes and channel requirements: RGB, Luminance, Normal, Alpha, etc.

We do our best to minimize file size without affecting visual quality.

We also generate multiple resolutions of each texture at every "power of 2" between 32×32 pixels and the original (up to 8192×8192). For example, if you upload a 1024×1024 texture, we will generate 32, 64, 128, 256, and 512 versions. Depending on your device, these are used in "LD" and "SD" modes in the viewer.

For performance reasons, non-"power of 2" textures will not be used; the viewer uses to the closest, smaller version.

Textures are re-processed each time you change Material settings, with a small delay. This can take 10-15 minutes to complete.

3D Settings always uses full resolution, uncompressed textures.

Automatic PBR Mapping

Use our texture naming conventions to help us automatically choose settings and apply textures to the right shader slots. The format is "MaterialName_suffix.extension". For example, if you have a material named "Material1", you could name your textures like "Material1_diffuse.png", "Material1_metallic.png", etc.

Avoid names with special characters, especially periods '.', underscores '_', and hyphens '-' because it can break the match.

These are the strings we look for in the suffix:

  • Diffuse / Albedo / Base Color: 'diffuse', 'albedo', 'basecolor'
  • Metalness: 'metalness', 'metallic', 'metal', 'm'
  • Specular: 'specular', 'spec', 's'
  • Specular F0: 'specularf0', 'f0'
  • Roughness: 'roughness', 'rough', 'r'
  • Glossiness: 'glossiness', 'glossness', 'gloss', 'g', 'glossy'
  • AO: 'ambient occlusion', 'ao', 'occlusion', 'lightmap', 'diffuseintensity'
  • Cavity: 'cavity'
  • Normal Map: 'normal', 'nrm', 'normalmap'
  • Bump Map: 'bump', 'bumpmap', 'heightmap'
  • Emission: 'emission', 'emit', 'emissive'
  • Transparency: 'transparency', 'transparent', 'opacity', 'mask', 'alpha'

Troubleshooting

  • Make sure you include the image files with the upload, and the .MTL file when uploading .OBJ.
  • Make sure the path and file names linking the textures are correct.
  • Try uploading your textures manually in 3D settings.
  • If applying a texture does nothing, or seems to apply a solid color, this can indicate a UV-mapping problem.
  • 3D scans and models with baked lighting often look best in Shadeless mode.
  • Avoid spaces and special characters in your material, texture, and file names. Name everything with ASCII / UTF-8 compliant characters.
  • Avoid image sizes bigger than 8192×8192 pixels.
  • Avoid image file sizes bigger than 10MB.

 For performance tips, see Viewer Performance.

3rd Party Rendering Engines

Proprietary renderers/shaders like V-Ray, and Mental Ray should have their lighting and textures baked for best results. The 3ds Max Exporter, for example, is able to bake materials and upload to Sketchfab automatically.

KeyShot currently offers no baking features and very limited material encoding in supported formats (STL and OBJ). Keyshot users should prepare materials/textures in other software or use PBR mode in Sketchfab without textures.

Have more questions? Submit a request

Comments

  • Avatar
    overthere

    Is it actually possible to bake lighting and texture from Keyshot, googling would seem to suggest not?

  • Avatar
    James

    @overthere - I've done quite a bit of googling myself, I also think not...

  • Avatar
    bigattck

    booo, making fbx not have texture is like not having water in the ocean.

  • Avatar
    James

    @bigattck - I'm not sure what you mean. We completely support textures in FBX, just not the specific "FbxLayeredTexture" http://help.autodesk.com/view/FBX/2015/ENU/?guid=_cpp_ref_class_fbx_layeredtexture_html

  • Avatar
    Kirill_llirik

    Hello James. Have a Sketchfab support import model with animation like a FBX Review? Its realy will be great for show 3d porfolio for animators.

  • Avatar
    James

    Hi Kirill,

    Not yet, but animation is a big milestone for us in the future!

  • Avatar
    KrzysztofZwolinski

    Can I pack textures to chanels ?? R-metallic, G-spec, B - ao etc. Les memory better performance special on web and mobile devices. Now im working with simple matcap shader that use only "Normalmap" and im using only R+G for normals, B is ambient and A is alpha.

  • Avatar
    James

    @KrzysztofZwolinski - Not completely, but it's something we might implement in the future. You can do it with a few specific slots. Alpha Blending/Alpha Masking can use Alpha (A) or Luminance (R). Emission can use Luminance (R), and Base Color/Albedo can use Luminance (R).

  • Avatar
    clockworxdesign

    Hi James, could i use animated textures in future? say upload a small gif for a blinking eye , or a short looping video clip to play on a TV on an exhibition stand or similar?

  • Avatar
    James

    @clockworxdesign - Yes, it's something we're experimenting with.

  • Avatar
    iqs99

    Hello can anyone tell me which type of normal map is accepted in Sketchfab, DirectX (X+, Y-, Z+) or OpenGL (X+, Y+, Z+) ?

  • Avatar
    James

    @iqs99 - We offer an "Invert Y" option in the normal map channel in order to support both formats:

    normal map invert y

  • Avatar
    degit22

    How to set in MTL file Diffuse / Albedo, Metalness, Specular, Roughness, Glossiness, Ambient Occlusion, Cavity, Normal, Bump, Emission, Opacity? Where an example?

  • Avatar
    James

    @degit22 - You need to set your texture names like they are defined above:

    https://help.sketchfab.com/hc/en-us/articles/202600873-Textures-Materials-Formats#obj

  • Avatar
    degit22

    @James - Before update work suffixes. Now textures do not automatically choose.

  • Avatar
    James

    @degit22 - Ah, I'm sorry. I think it might be related to this bug. Could you try the workaround here?

    https://forum.sketchfab.com/t/sketchfab-does-not-load-automatically-textures/5535

  • Avatar
    craftworkmobile

    Unity3d uses specular map from alpha channel. Is it possible to use it right from the texture alpha channel or I should use unique specular map?

  • Avatar
    James

    @craftworkmobile

    For Classic materials, we support RGB and Luminance (R) in the specular slot, but not Alpha (A).

    For PBR (Metalness workflow), Specular F0 map is optional, but we expect a linear, greyscale RGB image.

    For PBR (Specular workflow), we expect an RGB map in the Specular slot.

    So, in your case, yes I think you should use a unique specular map.

  • Avatar
    klonoaxlolo

    I have a klonoa model but when i add his textures his eyes aren't open all the way but his eyes are colored.  Someone please help me

  • Avatar
    James

    Hi @klonoaxlolo - You can make the eyelid materials 100% transparent in 3D Settings: http://puu.sh/ofL3H/8b78d89a0e.jpeg

  • Avatar
    frankmaraite

    In agisoft photoscan I can set 'UDIM texture layout' when exporting OBJ. Should I set this or not?

  • Avatar
    James

    @frankmaraite - I'm not really sure what that option does, but I never set it when I use PhotoScan.

  • Avatar
    jinkapo

    *coughs* So... I don't blame you from laughing at this, but I made a prop last night and was using sketchfab as a previewer while I was working on it at a public PC, so anyway, the computer decided to crashed and the files ended up becoming corrupt. So yeah, I was wondering if there is a way to retrieve my textures when the download property is a .blend file.

  • Avatar
    James

    @jinkapo - These things happen :)

    If you packed the texture in the .blend file before exporting, you should be able to extract them in Blender. If not, you can grab them from Developer Tools > Resources.

    Edit: Turn off image compression to make sure you're downloading your original versions and not our processed versions:

    https://sketchfab.com/models/f3339e611a5143f88c09b9dfb56a0c7f?image_compression=0

  • Avatar
    bicom

    .

  • Avatar
    James

    @jk76 - looks like you got some answers on the forum?

  • Avatar
    lukeyu

    Why "Invert Y" in the normal map would be a default setting ?

  • Avatar
    James

    @lukeyu - Because DirectX (-Y) is more common than OpenGL (+Y)

  • Avatar
    lukeyu

    Is it possible to let us to choose "Invert Y" option at once for all materials ?

  • Avatar
    lukeyu

    And according this table (http://wiki.polycount.com/wiki/Normal_Map_Technical_Details) I think you should use OpenGL as a default