assets-pipeline

Assets Pipeline in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

Related skills: audio-system for audio playback and bus architecture, 3d-essentials for 3D materials and lighting, 2d-essentials for 2D rendering and sprites, animation-system for imported animations, godot-optimization for asset-related performance, multithreading for threaded resource loading.

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1. How Importing Works

The Import System

When you add a file to res://, Godot auto-imports it based on its type. Import settings are stored in .import sidecar files alongside the original.

project/
├── textures/
│   ├── player.png           ← original file (committed to VCS)
│   └── player.png.import    ← import settings (committed to VCS)
└── .godot/
    └── imported/            ← compiled cache (NOT committed — .gitignore it)

Key Rules

• Never modify files in .godot/imported/ — they are regenerated from originals
• Commit .import files to version control — they store your settings
• Reimport after changing settings: select file → Import dock → click Reimport
• .godot/ should be in your .gitignore

Changing Import Settings

1. Select the file in the FileSystem dock
2. Open the Import dock (next to Scene dock by default)
3. Change settings
4. Click Reimport (or Reimport All for batch changes)

Import settings can also be set via Advanced Import Settings for 3D scenes (double-click the .glb/.gltf file).

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2. Image Import

Compression Modes

Mode	Quality	VRAM	File Size	Use For
Lossless	Perfect	High	Large	Pixel art, UI elements
Lossy	Good	High	Small	Large photos, backgrounds
VRAM Compressed	Reduced	Low	Small	3D textures, large 2D sprites
VRAM Uncompressed	Perfect	High	Large	When VRAM compression artifacts are unacceptable
Basis Universal	Reduced	Low	Very small	Cross-platform, multiple GPU formats

When to Use Each

Pixel art / UI icons       → Lossless (no artifacts, crisp pixels)
2D game sprites            → Lossless (small sprites) or VRAM Compressed (large sprites)
3D textures (albedo, normal) → VRAM Compressed (saves GPU memory)
Large backgrounds          → Lossy or VRAM Compressed
Mobile targets             → VRAM Compressed (essential for memory)

Key Import Settings

Setting	Description	Default
Compress > Mode	Compression algorithm (see table above)	VRAM Compressed
Mipmaps > Generate	Generate mipmaps for distance rendering	Off
Process > Fix Alpha Border	Prevents dark outlines on transparent sprites	On
Process > Premult Alpha	Pre-multiply alpha (avoids dark halos)	Off
Flags > Filter	Bilinear filtering (smooth) vs nearest (crisp)	Linear
Flags > Repeat	Enable texture tiling	Disabled

Pixel Art Setup

For crisp pixel art, set these project-wide:

Project Settings > Rendering > Textures > Canvas Textures > Default Texture Filter → Nearest

Or per-image in Import dock: Filter → Nearest

Enabling Mipmaps

Mipmaps prevent shimmering on textures viewed at an angle or from a distance. Required for 3D textures; optional for 2D.

• 3D textures: Always enable mipmaps (Import dock → Mipmaps → Generate → On)
• 2D sprites: Usually off (unless you use Camera2D zoom)
• UI textures: Off (rendered at fixed scale)

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3. 3D Scene Import

Supported Formats

Format	Extension	Recommendation
glTF	.gltf, .glb	Recommended — open standard, best support
Blend	.blend	Direct Blender import (requires Blender installed)
FBX	.fbx	Good for legacy pipelines
Collada	.dae	Older format, use glTF if possible
OBJ	.obj	Static meshes only — no animations/rigs

glTF is the recommended format. It has the best Godot support, is an open standard, and preserves materials, animations, and rigs accurately.

Node Naming Conventions

Godot auto-creates appropriate node types based on suffixes in your 3D model's object names:

Suffix	Generated Node	Example Name
-col	StaticBody3D + collision	Wall-col
-convcol	ConvexPolygonShape3D	Rock-convcol
-rigid	RigidBody3D	Barrel-rigid
-navmesh	NavigationRegion3D	Floor-navmesh
-occluder	OccluderInstance3D	BigWall-occluder

In Blender:                  In Godot (after import):
Wall-col                  →  StaticBody3D
├── Wall (mesh)           →    ├── MeshInstance3D
                          →    └── CollisionShape3D (auto-generated)

Import Dock Settings

Select the imported .glb/.gltf in FileSystem, then in the Import dock:

Setting	Description
Root Type	Override root node type (Node3D, RigidBody3D, etc.)
Root Name	Custom name for the root node
Meshes > Generate LOD	Auto-generate LOD levels (on by default)
Meshes > Light Baking	Static or Dynamic for lightmap baking
Animation > Import	Enable/disable animation import
Animation > FPS	Bake animation at this framerate

Runtime Scene Loading

# Preload at compile time (known path)
const ENEMY_SCENE: PackedScene = preload("res://models/enemy.glb")

# Load at runtime (path from data)
func spawn_model(path: String) -> Node3D:
    var scene: PackedScene = load(path)
    var instance: Node3D = scene.instantiate()
    add_child(instance)
    return instance

private static readonly PackedScene EnemyScene = GD.Load<PackedScene>("res://models/enemy.glb");

public Node3D SpawnModel(string path)
{
    var scene = GD.Load<PackedScene>(path);
    var instance = scene.Instantiate<Node3D>();
    AddChild(instance);
    return instance;
}

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4. Animation Import

Splitting Animations

If a 3D file contains a single timeline with multiple animations, split them in the Advanced Import Settings:

1. Double-click the .glb file to open Advanced Import Settings
2. Go to Animations tab
3. Add animation clips with start frame and end frame
4. Set loop mode per clip (None, Linear, Ping-Pong)

Retargeting Animations

Share animations between characters with different skeletons:

1. Import both the source (animation) and target (character) models
2. Open Advanced Import Settings on the target model
3. Go to Skeleton3D > Retarget settings
4. Map source bones to target bones
5. Use SkeletonProfile resources for standard humanoid mappings

Animation Import Settings

Setting	Description
Import	Enable/disable animation import
FPS	Bake framerate (30 is standard)
Trimming	Remove empty frames at start/end
Remove Immutable Tracks	Remove tracks that don't change

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5. Audio Import

For in-depth audio playback, bus setup, and music management, see the audio-system skill.

Format Recommendations

Format	Import As	Use For	Key Settings
WAV	AudioStreamWAV	Short SFX	Loop Mode, Mix Rate
OGG	AudioStreamOggVorbis	Music, long SFX	Loop, Loop Offset
MP3	AudioStreamMP3	Music (fallback)	Loop, BPM

Key Import Settings

Setting	Description	When to Use
Loop	Enable looping playback	Music, ambient loops
Loop Offset	Start position for loop restart	Avoid intro on loop
Force Mono	Convert stereo to mono	3D positional audio
BPM	Beats per minute	Rhythm games
Beat Count	Total beats in the track	Rhythm sync

Import tip: Use WAV for short SFX (zero decode latency). Use OGG for music (small file, good quality). Enable Force Mono for any audio used with AudioStreamPlayer3D — stereo doesn't spatialize properly.

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6. Resource Formats

.tres vs .res

Format	Type	Readable	Use For
.tres	Text	Yes	Resources you edit by hand or diff
.res	Binary	No	Large resources, faster loading

# Save as text resource
ResourceSaver.save(my_resource, "res://data/item.tres")

# Save as binary resource
ResourceSaver.save(my_resource, "res://data/item.res")

# Load (either format)
var resource: Resource = load("res://data/item.tres")

ResourceSaver.Save(myResource, "res://data/item.tres");
ResourceSaver.Save(myResource, "res://data/item.res");
var resource = GD.Load<Resource>("res://data/item.tres");

When to Use Each

• .tres — Custom resources you create and edit (item data, config, skill definitions). Version control friendly.
• .res — Generated or large binary data (baked lightmaps, navigation meshes, large meshes). Faster to load.
• .tscn — Text scene files (always use text for scenes — diffable in VCS)
• .scn — Binary scene files (rare — only for very large scenes where load time matters)

Threaded Resource Loading

Load large resources without freezing the game:

func load_level_async(path: String) -> void:
    ResourceLoader.load_threaded_request(path)

func _process(delta: float) -> void:
    var status := ResourceLoader.load_threaded_get_status(_loading_path)
    match status:
        ResourceLoader.THREAD_LOAD_IN_PROGRESS:
            var progress: Array = []
            ResourceLoader.load_threaded_get_status(_loading_path, progress)
            loading_bar.value = progress[0] * 100.0
        ResourceLoader.THREAD_LOAD_LOADED:
            var scene: PackedScene = ResourceLoader.load_threaded_get(_loading_path)
            get_tree().change_scene_to_packed(scene)
        ResourceLoader.THREAD_LOAD_FAILED:
            push_error("Failed to load: %s" % _loading_path)

public void LoadLevelAsync(string path)
{
    ResourceLoader.LoadThreadedRequest(path);
}

public override void _Process(double delta)
{
    var progress = new Godot.Collections.Array();
    var status = ResourceLoader.LoadThreadedGetStatus(_loadingPath, progress);
    switch (status)
    {
        case ResourceLoader.ThreadLoadStatus.InProgress:
            loadingBar.Value = (float)progress[0] * 100.0f;
            break;
        case ResourceLoader.ThreadLoadStatus.Loaded:
            var scene = ResourceLoader.LoadThreadedGet(_loadingPath) as PackedScene;
            GetTree().ChangeSceneToPacked(scene);
            break;
        case ResourceLoader.ThreadLoadStatus.Failed:
            GD.PushError($"Failed to load: {_loadingPath}");
            break;
    }
}

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7. Common Pitfalls

Symptom	Cause	Fix
Texture looks blurry	Filter is set to Linear for pixel art	Set Default Texture Filter to Nearest in Project Settings
Dark outlines on transparent sprites	Alpha border not fixed on import	Enable "Fix Alpha Border" in Import dock
3D model has no collisions	No naming suffix in source model	Add -col suffix to mesh names in Blender, or add manually
Imported animations missing	"Import Animation" disabled in Import dock	Enable Animation > Import and reimport
Texture VRAM too high on mobile	Using Lossless compression for large textures	Switch to VRAM Compressed for textures > 256px
3D textures shimmer at distance	Mipmaps not generated	Enable Mipmaps > Generate in Import dock
Audio has pop/click at loop point	Loop offset not set correctly	Adjust Loop Offset in Import dock; add fade in audio editor
Scene file is enormous	Using binary .scn instead of .tscn	Save scenes as .tscn (text) for VCS; use .scn only if needed
Import settings lost after reclone	.import files not committed to VCS	Always commit .import files; only .godot/ goes in .gitignore
Threaded load freezes game	Checking status every frame with load()	Use ResourceLoader.load_threaded_request/get_status pattern

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8. Implementation Checklist

• .gitignore excludes .godot/ but NOT .import files
• Pixel art projects set Default Texture Filter to Nearest in Project Settings
• 3D textures have mipmaps enabled (Import dock → Mipmaps → Generate)
• Large textures use VRAM Compressed (especially on mobile targets)
• 3D models use glTF format (.glb or .gltf) as the primary import format
• Collision shapes use naming suffixes (-col, -convcol) in the 3D authoring tool
• Animations are split into individual clips in Advanced Import Settings
• Audio SFX uses WAV; music uses OGG Vorbis
• 3D positional audio files are imported as mono (Force Mono enabled)
• Custom data resources use .tres (text) for version control diffability
• Large or runtime-loaded resources use ResourceLoader.load_threaded_request()
• Scene files use .tscn (text format) for version control