PBR Texture Map Cheat Sheet for Real-Time 3D Assets

Physically based rendering, commonly shortened to PBR, helps 3D materials respond consistently to lighting. Instead of painting every highlight and shadow directly into a colour texture, artists use separate maps to describe properties such as colour, surface roughness, metallic behaviour and fine detail.

This approach makes an asset easier to move between scenes and rendering environments. A metal tool, painted wall or fabric bag should retain its basic material identity whether it appears outdoors, inside a dark room or beneath coloured lighting.

However, PBR terminology can be confusing. Different applications may use different channel names, and a texture that looks correct in one program may appear too shiny, too dark or incorrectly inverted after export.

This cheat sheet explains the most common texture maps, how they should be configured and what to check before importing a textured model into a real-time engine.

PBR Maps at a Glance

Texture map	Controls	Typical appearance	Colour space
Base Color or Albedo	Visible surface colour	Full-colour image without baked lighting	sRGB
Roughness	Sharpness of reflections	Greyscale	Linear or Non-Color
Metallic	Whether the surface behaves like metal	Usually black or white	Linear or Non-Color
Normal	Small surface direction changes	Blue-purple image	Linear or Non-Color
Height or Displacement	Apparent or actual surface depth	Greyscale	Linear or Non-Color
Ambient Occlusion	Contact and crevice shading	Greyscale	Linear or Non-Color
Opacity	Visible and transparent areas	Greyscale or alpha channel	Linear or Non-Color
Emissive	Areas that appear to produce light	Colour or greyscale	Usually sRGB

The exact setup varies between rendering systems. Always check the requirements of the destination engine instead of relying entirely on how the material appears in the texturing application.

Base Color or Albedo Map

The base colour map defines the visible colour of a surface. It may contain painted patterns, stains, labels and colour variation, but it should generally avoid directional lighting information.

A base colour texture should not contain:

• Strong painted highlights
• Deep directional shadows
• Reflections from the reference photograph
• Ambient occlusion that will be added elsewhere
• Metallic reflections
• Lighting tied to a particular camera angle

Baked lighting may initially make a texture look detailed. Once the object moves beneath a different light source, however, the fixed shadows and highlights can conflict with the scene.

Quick check

Display the base colour map by itself. If the lighting direction is obvious even without a 3D model, the texture may contain too much baked illumination.

Roughness Map

The roughness map controls how broadly reflected light spreads across a surface.

In a conventional roughness workflow:

• Black represents a smooth surface with sharp reflections.
• White represents a rough surface with broad, diffused reflections.
• Grey values represent intermediate levels.

A polished metal panel may use darker roughness values, while dry concrete or unfinished wood will generally be lighter. Real objects rarely have perfectly uniform roughness, so subtle variation can make surfaces more believable.

Roughness does not simply mean brightness. A dark object can be rough, and a light-coloured object can be smooth.

Common mistake

Some tools use a glossiness or smoothness map instead. This normally represents the inverse concept: white is smooth and black is rough. If a material looks polished where it should be dull, check whether the channel needs to be inverted.

Metallic Map

The metallic map tells the renderer which parts of a material behave like metal.

In most metallic-roughness workflows:

• Black represents a non-metal.
• White represents a metal.
• Values between black and white are used sparingly.

Wood, plastic, stone, skin and fabric are non-metallic. Iron, aluminium, copper and exposed steel are metallic.

A painted metal object requires special attention. The paint is a non-metallic coating, while exposed scratches may reveal metal underneath. The metallic map should therefore follow the material itself rather than the object’s general identity.

Quick check

Ask what substance is visible at each pixel. If the viewer is looking at paint, dirt or rust rather than exposed metal, that area usually should not be fully metallic.

Normal Map

A normal map changes how light interacts with the surface without adding corresponding geometric detail. It is useful for representing scratches, fabric weave, shallow grooves, pores and small bevels.

Most tangent-space normal maps have a blue-purple appearance. They should be imported as data rather than colour images.

Normal maps are particularly valuable in real-time projects because they can preserve the impression of detail when geometry has been reduced. However, they do not change the model’s silhouette. A large ridge, deep opening or shape visible around the edge of an object still needs geometry.

Common problems

• The green channel is inverted.
• The texture is imported as sRGB.
• The normal strength is too high.
• UV seams create visible shading breaks.
• Details are too deep for the scale of the object.
• The mesh uses incompatible tangent settings.

DirectX and OpenGL workflows may interpret the vertical component differently. If dents look like bumps, or bumps look like dents, check the target engine’s normal-map convention.

Height and Displacement Maps

Height maps use greyscale values to describe relative depth. Their effect depends on how the material or renderer uses them.

A height map may drive:

• Bump mapping
• Parallax effects
• Tessellation
• True geometric displacement

Bump and parallax techniques create the appearance of depth without substantially changing the mesh. True displacement can move vertices and alter the silhouette, but it requires sufficient geometry and may carry a higher performance cost.

Quick check

Use height information for larger depth transitions than those represented in the normal map, but confirm whether the target platform supports the intended displacement method.

For mobile games or distant assets, normal mapping may provide a better balance between appearance and performance.

Ambient Occlusion Map

An ambient occlusion map adds subtle darkening where surfaces meet or where indirect light is naturally restricted. Typical areas include creases, corners, bolt recesses and contact points between components.

Ambient occlusion can help small details remain readable, but it should not be used as a substitute for proper lighting.

Heavy occlusion may cause:

• Dirty-looking surfaces
• Unnaturally black corners
• Loss of detail in dark scenes
• Shading that remains fixed when parts move
• Double-darkening when the engine adds real-time occlusion

Quick check

Reduce the map’s strength and compare the result. If the object loses its entire sense of structure, too much form may depend on baked shading.

Opacity and Alpha Maps

Opacity maps define which areas of a material are visible.

They are commonly used for:

• Foliage
• Fences
• Hair cards
• Torn fabric
• Decals
• Thin decorative patterns

Depending on the engine, transparency may be handled through alpha clipping, alpha blending or a dedicated mask channel.

Alpha clipping creates a hard visible-or-invisible boundary and is often more efficient and predictable for foliage or fences. Alpha blending supports partial transparency but can introduce sorting problems and additional rendering cost.

Quick check

If the material only needs hard cut-out edges, use a masked workflow where possible. Reserve blended transparency for effects that genuinely require partial visibility.

Emissive Map

An emissive map marks areas that appear self-illuminated, such as screens, signs, magical symbols and indicator lights.

Emission can make a surface appear bright even when the surrounding environment is dark. Whether it actually casts light into the scene depends on the engine, renderer and lighting configuration.

Avoid using excessive emission to compensate for poor scene lighting. Very high values may destroy texture detail, create distracting bloom or make an object difficult to balance across environments.

Quick check

Test the material with bloom disabled and under both bright and dark lighting. The source pattern should remain readable instead of becoming a featureless white shape.

Channel Packing

Several greyscale maps can sometimes be stored in the red, green, blue and alpha channels of a single texture. This is known as channel packing.

A project might combine:

• Ambient occlusion in red
• Roughness in green
• Metallic in blue

The exact arrangement depends on the engine and studio pipeline. Channel packing can reduce the number of texture samples and files, but an undocumented layout can quickly cause mistakes.

The officialglTF 2.0 specification defines a metallic-roughness material model and explains how material textures and channels are represented in glTF assets. In this format, roughness and metallic information can share different channels of the same texture.

Quick check

Never identify a packed map by its filename alone. Confirm which property is stored in each channel and document the convention for the project.

Colour Space Reference

Incorrect colour-space settings are a common reason materials look wrong after import.

Use sRGB for:

• Base colour
• Emissive colour
• Other textures intended to be viewed as colour

Use Linear or Non-Color for:

• Roughness
• Metallic
• Normal
• Height
• Ambient occlusion
• Opacity masks
• Packed data maps

Colour textures need gamma-aware interpretation because they represent visual colour. Data maps contain numerical material values and should not receive the same colour correction.

Texture Resolution Reference

Texture resolution should reflect how large the asset appears on screen, not simply how important the object feels to its creator.

Common square texture sizes include:

• 256 × 256
• 512 × 512
• 1024 × 1024
• 2048 × 2048
• 4096 × 4096

Larger textures can preserve more detail but increase memory use, download size and loading time. A small background object may not benefit from a 4K texture, especially when it occupies only a few pixels on screen.

When setting resolution, consider:

• Normal viewing distance
• Screen coverage
• Target platform
• Number of similar assets
• Texture compression
• Available memory
• Whether materials can be shared
• Whether a texture atlas is appropriate

Quick check

View the asset at its expected gameplay distance. If reducing the resolution produces no visible difference, the larger version may be unnecessary.

Texel Density

Texel density describes how much texture resolution is assigned to a given amount of model surface.

Consistent texel density helps nearby objects display a similar level of sharpness. Without it, one part of a character might look crisp while another appears blurry, even though both use the same texture dimensions.

Exceptions can be intentional. A character’s face may receive more texture space than the soles of their shoes because the face appears more often in close-up.

Quick check

Apply a checker texture before final texturing. Look for squares that change size, stretch or become distorted across different parts of the model.

Using AI to Create an Initial PBR Material

Manually producing complete texture sets can take considerable time, particularly when a team is testing several visual directions.

Meshy’s AI texture generator can apply textures to an uploaded 3D model using a text description or reference image. The feature supports uploaded OBJ, FBX and GLB models and can produce PBR maps including albedo, normal, roughness and metallic information.

For example, an artist could upload an untextured science-fiction storage crate and describe it as:

Worn dark-green painted metal, scratched corners, subtle dust, faded warning stripes, realistic industrial game asset.

The initial result can help the team compare styles or prepare a prototype more quickly. It should still be treated as a draft rather than an automatically approved production material.

After generation, inspect:

• Whether the texture follows the UV layout
• Whether seams are visible
• Whether lettering or symbols are distorted
• Whether metal and non-metal regions are classified correctly
• Whether highlights or shadows are baked into the base colour
• Whether roughness variation matches the material
• Whether texture resolution suits the target platform
• Whether the maps are assigned to the correct colour spaces
• Whether the result remains consistent under different lighting

AI can accelerate the first pass, but the artist remains responsible for material logic, technical optimisation and visual consistency.

Prompt Formula for AI Texturing

A useful texture prompt can follow this structure:

Material + colour + condition + surface details + style + intended use

Example:

Brushed aluminium casing, cool grey, lightly used, fingerprints and fine edge scratches, realistic PBR style, first-person game prop.

Another example:

Hand-painted wooden shield, muted red and cream, weathered edges, visible grain and small chips, stylised fantasy game asset.

Avoid relying only on broad descriptions such as “make it realistic.” A more specific prompt gives the system useful information about the surface and its intended appearance.

Pre-Export Material Checklist

Before exporting a textured asset, confirm the following:

• The base colour does not contain unwanted lighting.
• Roughness values match the intended surface.
• The metallic map reflects the visible material.
• Normal maps use the correct orientation.
• Height effects are suitable for the target platform.
• Ambient occlusion is not excessively dark.
• Transparency uses the appropriate rendering mode.
• Emissive areas retain visible detail.
• Data maps are imported without sRGB correction.
• Packed texture channels follow the project convention.
• Texture dimensions match the asset’s screen size.
• UV seams and stretching have been inspected.
• File names clearly identify each map.
• The material has been tested under multiple lighting conditions.

Common Naming Conventions

Clear filenames make texture sets easier to review and automate.

A simple convention might use:

Suffix	Texture
_BaseColor or _Albedo	Base colour
_Roughness	Roughness
_Metallic	Metallic
_Normal	Normal
_Height	Height or displacement
_AO	Ambient occlusion
_Opacity	Opacity
_Emissive	Emissive
_ORM	Packed occlusion, roughness and metallic

The team should choose one naming standard and use it consistently. Mixing terms such as glossiness and roughness without indicating inversion can cause avoidable import errors.

Troubleshooting Quick Reference

The model looks too shiny

Check the roughness map, its colour-space setting and whether a glossiness map was interpreted as roughness.

Metal looks like plastic

Confirm that exposed metal regions are white in the metallic map and that the base colour contains appropriate metal colour information.

Bumps appear inverted

Invert the normal map’s green channel or export it using the convention required by the target engine.

The texture looks washed out

Check whether the base colour has been imported using the wrong colour space or processed twice as sRGB.

UV seams are visible

Inspect UV padding, normal-map continuity, texture filtering and mipmaps. Increase padding when lower-resolution mip levels cause neighbouring islands to bleed together.

Transparent objects render in the wrong order

Use a masked material when soft transparency is unnecessary. If blending is required, review the engine’s sorting and material settings.

The material looks correct in one scene but wrong in another

Remove baked lighting from the base colour, review roughness values and test the asset under neutral lighting.

Final Thoughts

A PBR material is a coordinated set of surface instructions rather than a collection of decorative images. Base colour defines visible colour, roughness controls reflection sharpness, metallic identifies exposed metal, and normal maps add small-scale lighting detail. Additional maps handle depth, occlusion, transparency and emission.

AI-assisted texturing can make early material creation faster, but technical knowledge remains essential. Artists must still inspect UV coverage, distinguish metals from non-metals, configure colour spaces and test every asset inside its destination engine.

The most reliable workflow combines efficient tools with a clear texture standard. When map names, channels, resolutions and import settings are documented consistently, assets are easier to review, optimise and reuse across real-time projects.