Baking Textures In Blender For Export To Game Engines And Other Tools

Baking textures is an essential technique in 3D content creation pipelines. It allows 3D artists to render complex materials, textures, and effects into a simple 2D image map. This map can then be efficiently exported and used in game engines, VR/AR applications, 3D printing, and more. The baking process reduces texture memory usage, bakes complex shader networks into standard images, and prepares clean efficient textures for export.

Why Bake Textures?

There are several key reasons to bake textures in Blender:

Reduce texture memory usage – Baking allows complex materials to be condensed into simple 2D texture maps, reducing VRAM usage for real-time rendering engines.
Bake complex materials into textures – Intricate shader node networks with many texture inputs can be rendered to bake all qualities into a single 2D image.
Export clean and efficient textures – Baking gives optimized textures with only essential qualities for export to external applications.

In short, baking creates lightweight textures perfectly optimized for export – reducing memory loads and providing efficient textures flows for external engines and software.

Setting Up Your Model

Before baking, models must have proper UV mappings and materials assigned. This setup stage impact bakes quality and efficiency:

UV unwrapping for texture space – UV maps define how models map to 2D textures. Clean, non-overlapping UVs are essential for bakes.
Assigning materials and textures – Materials and image textures must be assigned before baking so render output has sources to bake from.

With UVs and materials defined, models are fully ready for the baking process. Well-constructed UVs and material networks yield higher-quality bakes later on.

Baking Workflow

The baking process has three core steps:

Setting up the bake – Configuring bake settings and output texture.
Choosing bake settings – Determining which attributes to bake out.
Executing the bake – Running the actual baking process.
Saving baked textures – Storing baked maps and exporting.

Understanding this workflow is key to efficiently using the Bake tab in Blenderís Camera Data properties. Each step handles critical configurations that dictate quality, accuracy, and performance.

Setting Up The Bake

When first setting up a bake, the output texture and destination must be defined:

Create a new image texture to store the baked result.
Set the bake destination to Image Texture so bakes export to the new image.
Set color space, bit depth, resolution, and format for the target image.

Properly creating and configuring the output image prepares the perfect container to store the final bake. If settings are incorrect, bakes may clip or bake inaccurately.

Choosing Bake Settings

With output set up, bake settings control what data transfers into the target texture:

Scene selection bakes from all objects or just selected ones.
Bake Mode sets which material qualities to transfer like diffuse, normals, emissivity, etc.
Set ray distance and margin to fine-tune the ray tracing properties.
Apply cage when baking finely detailed outputs.

Choosing the right settings ensures the essential material qualities bake out. These settings inform the ray tracing pass about what data to record and store.

Executing The Bake

With output and settings configured, execute the actual bake:

Check Selected to Active to bake from all objects to the active one.
Click Bake to run the ray tracing pass, recording output to the target texture.
Save the image with the baked qualities embedded once complete.

The bake handles the intensive calculations and rendering. Long or complex bakes may take significant time. Once finished, the target image retains all baked qualities.

Saving Baked Textures

Upon baking, the output image will contain the rendered qualities from the modelís materials. It’s essential to save these maps:

Verify bake accuracy and quality first.
Export and save the images externally if needed.
Optionally reload images to continue editing.

Saving bakes archives the processed texture for export. If quality issues exist, tweak settings and rebake until the texture exports correctly.

Baking Different Map Types

Many distinct texture map types are valuable to bake from Blender models. Each map has specific uses in real-time engines:

Diffuse/Albedo – Base color and brightness information.
Normal – Per-pixel directional detail for lighting.
Ambient Occlusion – Shadow and crevice shading.
Curvature – Highlights convex/concave geometry features.
Displacement – Vector depth map for mesh deformation.

When baking, choosing the appropriate map type outputs exactly the kind of data required later during rendering. For example, video game engines leverage diffuse, normal, and ambient occlusion maps extensively.

Diffuse/Albedo Maps

Albedo or diffuse maps store basic color and brightness information defining how materials reflect light. They represent the base colors applied to each material in the Blender scene and influence surface appearance directly.

These maps export well to game engines. When rendering, the lighting pipelines multiply scene lighting and shadows with the albedo map to calculate final pixel values. This handles dynamic lighting while preserving hand-painted color details.

Normal Maps

In contrast to diffuse maps, normal maps contain directional detail for surface lighting calculations. Instead of colors, each RGB pixel encodes a vector normal direction influencing that screen space location.

When exported, game engines apply pixel normal data to lighting equations. This approximates complex beveled and bumpy details without heavier geometry. Tangent space normal maps work best for general game engine pipelines.

Ambient Occlusion

Baked ambient occlusion maps store static shadowing based on underlying geometry. Tight cracks, crevices, and overlaps appear darker while open areas remain brighter.

When exported, ambient occlusion adds instant realism to basic shaders. Subtly darkening background shadows supplements expensive pipeline steps like global illumination. Dirt, wear, erosion, and dark accents visualize well with ambient occlusion maps.

Other Maps

Other more advanced bake types like curvature, displacement, and emissive maps help special effects rendering. Curvature maps dynamically shade based on model concavity to accentuate bevels. Displacement maps deform proxy mesh geometry based on vector lift data. Emission maps define glowing surface elements like lights, embers, and neon.

Baking these data types requires specific Blender setups to capture accurately. But once exported, they significantly expand available looks and behaviors in real-time.

Troubleshooting Common Baking Issues

Various artifacts and errors can hamper baking results. However, Blender provides tools to troubleshoot and resolve most common problems:

Artifacts – Fix via adjusting margin, ray distance, cage, subdivision settings.
Noise – Reduce samples per pixel. Check texture interpolation.
Texture bleeding – Adjust UV islands density or padding.
Quality – Increase samples, texture size. Check lighting and material networks.

Finding the root cause of errors involves methodically assessing settings, UVs, and scene materials. Test small changes between rebakes to isolate specific solutions.

Eliminating Artifacts and Noise

Flickering pixels, blotches, strange shadows, and other artifacts stem from various indirect baking causes. Noisy results come from low sampling rates struggling to smooth gradients:

Increase the ray distance so shadows bake further.
Higher margin values extend the catch area.
Try enabling Selected to Active.
Add a cage object to control bake sampling.

If issues continue, boost sample counts until noise disappears. Higher values exponentially slow baking, so find the minimum usable samples through testing.

Avoiding Texture Bleeding

Texture bleeding manifests as unwanted diffuse colors overlapping UV seam edges. Materials from adjacent islands pollute across borders during baking.

Strategies to avoid bleeding issues include:

Pack UV islands closer to reduce margin distance traveled.
Add padding gaps in the UV texture space between islands.
Split problematic meshes into separate objects to avoid leakage.

Carefully packing charts and managing continuity often solves most bleeding defects. Custom margin padding values in the UV space may help severe cases.

Improving Overall Bake Quality

Low overall quality with poor detail or clarity degrades texture map exports. Try these tips to vastly improve bakes:

Boost texture output size for higher-resolution results.
Review scene lighting for even diffuse response.
Check material nodes for errors preventing full export.
Increase sample counts if noise affects clarity.

Taking advantage of Blenderís functionality for baking verification helps perfect final texture exports. Iteratively tweak settings like any rendering task until the baked map matches the viewport.

Optimizing Textures for Export

When baking for export to external programs, texture format and compression settings matter greatly. Target output dictates ideal texture parameters for size, artifacts, and compatibility:

Game engines prefer PNG formats for diffuse, normal maps.
3D printing accepts higher-quality EXR or HDR images.
Adjust compression levels for intended display resolution.
Scale texture dimension powers of 2 for GPU efficiency.

Determining exact texture properties depends directly on downstream usage. Test asset visualization in final software when possible to check export quality.

Choosing Size and Resolution

Ideally texture resolution matches final pixel density for crispest results. But larger textures raise memory loads. Finding the best balance depends on target hardware restrictions and desired visuals:

Mobile games need smaller 2048×2048 textures due to memory caps.
Desktop games can apply huge 8192×8192 textures for ultra details.
VR/AR applications require 4096×4096 or larger maps to avoid visible pixels.

Planning texture sizing around target display density and hardware bottlenecks prevents wasted texture space or jagged edges.

Setting Compression Level

Texture compression reduces file sizes, optimizing storage and transmission. But artifacts appear if compression passes visible thresholds:

Low compression maintains high quality at larger file size.
Higher compression introduces defects but improves performance.
Tune settings to balance visuals versus memory constraints.

Testing directly on target devices catches compression issues before release. Target at least 8x compression for typical game engine outputs.

Choosing File Formats

Exporting baked texture maps relies primarily on two formats:

PNG – Lossless quality useful for diffuse, normal maps.
JPEG – Compressed format good for photos and emissive maps.

Other formats like EXR or TIFF apply for high bit-depth HDR texture output. Determine final format based on texture use and quality requirements.

Exporting Baked Textures

With rendering complete and textures optimized, exporting prepares assets for integration into external 3D pipelines. Export requirements vary greatly between game engines, 3D printing, and VR systems.

Game Engine Exports

Games need an entire suite of channel-packed texture sets sharing UV mappings to simulate complex materials:

Albedo, normal, roughness maps as a minimum set.
Emissive, ambient occlusion maps for enhanced effects.
Alpha masks to dictate opacity and translucency.

Follow specific game engine guidelines for template textures with packed channels. Unity, for example, expects textures in its standardized material format.

3D Printing Exports

Unlike real-time engines, 3D printing relies primarily on single color-based outputs for material changing extruders:

Black and white masks trigger nozzle material swaps.
8-bit RGB textures alter color toning.
16 to 32-bit EXR/HDR files provide smoothing and fine details.

Printing exports focus more on geometry rather than textures. But colormap variations help leverage multi-material hardware uniquely.

AR/VR Exports

Emerging virtual and augmented reality formats handle textures differently than traditional applications:

VRChat and other social worlds prefer MMD, CATS Blender plug-in pipelines.
Custom shaders often handle stylization in Unity, Unreal engines.
Volumetric captures use Reflectance Transformation Imaging for unique bakes.

Study specific VR/AR software documentation to determine ideal texture export workflows. Bandwidth and display resolution heavily influence quality targets.

In summary, baking provides efficient, compact textures tuned for exterior pipelines. Tailor output specifically for downstream 3D, print, game, and VR uses based on format requirements, hardware restrictions, and intended display parameters.