| name | organic-model |
| description | Use when generating organic shapes — trees, rocks, mushrooms, coral, bushes, alien plants, vines, crystals, fruit, bones. The "easy mode" of 3D generation; AI artifacts read as natural irregularity. Trigger on "make a tree", "generate rocks", "I need foliage", "mushroom prop", "alien plants", "fill the scene with shrubs", "scatter some boulders". |
| license | MIT |
| compatibility | ["Cursor","Claude Code","Windsurf","Codex"] |
| category | 3d-assets |
| user-invocable | true |
| allowed-tools | Read Grep summer_search_assets summer_list_my_assets summer_get_asset summer_import_asset_by_id summer_generate_3d summer_generate_image summer_import_from_url summer_add_node summer_set_prop summer_inspect_node summer_get_scene_tree summer_save_scene |
| paths | ["assets/organic/**","assets/models/**","**/*.tscn","**/*.gd"] |
Organic Model — Easy-Mode 3D Generation
Organic shapes (trees, rocks, mushrooms, coral, alien flora, crystals, vines, bones) are the most forgiving category for AI 3D generation. Lumps look natural. Asymmetry looks natural. Smoothing-group artifacts read as bark texture. The "melted" look that ruins vehicles and characters is fine on a mossy boulder.
This is the cheapest, fastest way to fill out a scene. Use it liberally — it's the recommended go-to when the user says "this scene feels empty". Each generation is ~$0.30–0.50, and the failure rate is the lowest of any 3D-asset family.
Backing tool: summer_generate_3d. Default hunyuan is great here, but trellis is faster and quality difference is mostly invisible on organic shapes — trellis is the recommended pick when generating many at once.
When to use
- "Make me a pine tree."
- "Generate five different rocks I can scatter."
- "I need glowing mushrooms for the cave."
- "Fill this forest scene with foliage."
- "Alien plants for the planet surface."
- "Coral for the underwater level."
- The user wants visual density without spending a lot of money or time.
When NOT to use
- Character (humanoid, even if "tree-person") →
summer:3d-assets/character-model (rigging matters).
- Vehicle, weapon, hard-surface object →
summer:3d-assets/prop-model or summer:3d-assets/vehicle-model.
- Tileable ground (grass field, sand) →
summer:asset-pipeline/asset-strategy Pipeline 2 (textures, not meshes).
- Animated organic (Venus fly trap that opens, breathing pod) → generate static here, animate in-engine with bones or shape keys.
- A single hero-tree centerpiece (Yggdrasil, the One Tree) — generate via
summer:3d-assets/prop-model with higher polycount and detail attention.
Polycount targets
Organic geometry tolerates aggressive polycount cuts because the silhouette is irregular — viewers can't spot poly-count drops the way they spot a low-poly cylinder.
| Use case | Tris | Pass via |
|---|
| Hero tree (mid-distance, prominent) | 4k–8k | target_polycount: 6000 |
| Background tree (forest filler) | 1k–3k | target_polycount: 2000 |
| Distant tree (use billboard imposter) | 200–500 | target_polycount: 400 |
| Large rock / boulder | 800–2000 | target_polycount: 1500 |
| Small organic (mushroom, fruit, crystal) | 300–1000 | target_polycount: 600 |
| Vine / branch decoration | 200–500 | target_polycount: 400 |
Generating a forest? Make 3 hero trees + 5 background trees + 3 rocks at low polycount, then scatter via MultiMeshInstance3D for hundreds of copies at near-zero rendering cost.
Steps
1. Search before generating
summer_search_assets(query="<organic type>", assetType="3d_model", source="all")
2. Build the prompt
Pattern: <species> + <state/condition> + <key features> + isolated suffix. Organic prompts are shorter than prop prompts — the model already knows what a tree looks like.
| Goal | Prompt that works |
|---|
| Pine tree | A tall pine tree with dense green needles and a straight trunk, slight lean. Game asset, stylized low-poly game art, white background, isolated object. |
| Oak tree | A wide oak tree with sprawling branches and seasonal autumn leaves in orange and red. Game asset, stylized, white background, isolated object. |
| Boulder | A large mossy boulder, irregular weathered surface, patches of green moss on top. Game asset, stylized, white background, isolated object. |
| Glowing mushroom | A cluster of three bioluminescent mushrooms on a small mossy base, pale cyan glow, translucent caps. Game asset, stylized, white background, isolated object. |
| Alien plant | An alien spiral plant with tendril-like fronds, deep purple with glowing pink tips, growing from a bulbous base. Game asset, stylized, white background, isolated object. |
| Coral cluster | A branching coral cluster, bright orange and pink, sea-fan shapes, multiple branches. Game asset, stylized, white background, isolated object. |
| Crystal | A jagged amethyst crystal cluster growing from a stone base, deep purple with translucent facets. Game asset, stylized, white background, isolated object. |
| Vine | A hanging jungle vine with broad green leaves and small white flowers, ~2 meter length. Game asset, stylized, white background, isolated object. |
Organic prompts that DON'T work:
| Bad prompt | Failure mode |
|---|
a tree | Returns a generic tree, but inconsistent species across regenerations — the scene looks chaotic. Always specify species. |
a forest | Returns one fused mesh of multiple trees → impossible to scatter. Generate one tree, scatter via MultiMeshInstance3D. |
realistic tree with photoreal bark | Realistic = expensive polycount, ugly when stylized assets surround it. Match scene style. |
a tree on a hill | The hill becomes geometry. Always say isolated object. |
3. Confirm and call
About to generate pine_tree_01 via trellis, target ~2k tris. ~$0.30, ~30s. OK?
For batch generation, batch the confirmation:
About to generate 3 trees + 3 rocks + 5 mushrooms (11 generations, ~$3.50, ~5 min). All low-poly via trellis. OK?
summer_generate_3d(
prompt="A tall pine tree with dense green needles and a straight trunk, slight lean. Game asset, stylized low-poly game art, white background, isolated object.",
model="trellis",
options={ target_polycount: 2000 },
wait=true
)
summer_get_asset(assetId="<assetId>")
summer_import_asset_by_id(assetId="<assetId>", path="res://assets/organic/pine_tree_01.glb")
4. Generate variation, not duplication
If the user wants "five rocks", don't generate one rock and copy it five times in the scene — generate five subtly different prompts:
"A medium boulder, mossy granite, rounded shape"
"A medium boulder, weathered limestone, sharp jagged edges"
"A medium boulder, dark basalt, flat-topped"
"A medium boulder, sandstone, layered horizontal striations"
"A medium boulder, mossy granite, tall narrow shape"
Then scatter all five with random rotation. Five unique meshes + rotation = looks like 50 unique rocks.
5. Wire into the scene
| Use case | Wiring | Notes |
|---|
| Single hero tree, mid-scene | MeshInstance3D under Node3D | One per scene; nothing fancy |
| Forest scatter (50+ trees) | MultiMeshInstance3D with one mesh ref | Single draw call for all instances |
| Foliage variety (3 species) | One MultiMeshInstance3D per species | Each species is one draw call |
| Distant trees | Billboard imposter (Sprite3D with a tree image) | Switch from mesh to billboard at ~50m via LOD |
| Rocks with collision | StaticBody3D parent + CollisionShape3D (ConcaveShape from mesh) | Only for rocks the player can walk into |
| Rocks without collision (background) | Just MeshInstance3D | Most distant rocks don't need it |
Hero tree:
summer_add_node(parent="./World/Forest", type="MeshInstance3D", name="HeroOak")
summer_set_prop(path="./World/Forest/HeroOak", property="mesh", value="res://assets/organic/oak_tree.glb")
summer_save_scene
Forest scatter (MultiMesh): create a MultiMeshInstance3D, assign a MultiMesh resource referencing the tree mesh, set instance_count to e.g. 100, and populate set_instance_transform() from a script with random positions + rotations. See summer:scene-composition for the scatter pattern.
6. LOD and billboards
For dense forests, the cheapest fix beyond MultiMesh is the billboard imposter:
- Generate the tree mesh once at high polycount.
- Render it from one angle to a transparent PNG (Godot's
EditorScript can capture a viewport).
- Use that PNG as a
Sprite3D with billboard = enabled.
- Swap from
MeshInstance3D to Sprite3D at ~50m camera distance via Godot's VisibleOnScreenNotifier3D or a custom LOD script.
For a 200-tree forest, ~10 close trees are real meshes, 190 are billboards. Frame budget saved: ~80%.
Anti-patterns
- Generating "a forest" as one prompt. Returns a single fused mesh — useless for placement. Always one species per generation, then scatter.
- Regenerating the same species 5 times for variety. Generate 5 different species/states/colors for true variety; identical regenerations don't differ enough.
- High polycount on background organics. A 30k-tri rock used 50 times in the background tanks the frame rate. Cap distant organics at 2k.
- Ignoring MultiMeshInstance3D. 100 individual MeshInstance3D nodes = 100 draw calls. 100 instances of one MultiMesh = 1 draw call. Same visual result.
- Adding collision to every leaf and pebble. Player only needs collision on things the body can hit. Skip it for distant scenery and small ground litter.
- Using
meshy (legacy). No reason to — trellis is faster and hunyuan is higher quality.
Edge cases
- Animated foliage (wind sway). Generate static here, then add wind sway via a vertex shader on the material —
summer:vfx/shaders (when available). No animation rig needed.
- Underwater organics (kelp, anemones). Same flow; expect Hunyuan to add a "ground attachment" base unless you say
floating, suspended in water.
- Branching meshes (vines, roots) come back too thick. Specify
thin tendril, fine branches, or accept and scale Y down in the editor.
- Snow / ice / frozen variant. Add
covered in snow, frosted, ice crystals to the prompt — works well on trees and rocks. For temperature variants of the same scene, generate the variant rather than retexturing.
- Crystal/glass organic. Mesh comes back opaque. Generate the geometry, then assign a
StandardMaterial3D with transparency = ALPHA and emissive in the editor.
- Bones, skulls, dead trees. All work great — organic forgives them more than props would. Add
weathered, sun-bleached for desert / tundra feel.
Fallback (no MCP)
- Run prompts at the Summer dashboard or any 3D-gen web playground (Hunyuan, Trellis, Meshy).
- Download
.glb files into res://assets/organic/.
- Build scatter scenes manually in Godot.
For totally free / offline alternatives: Quaternius (free stylized organics), AmbientCG (rocks + textures), Sketchfab free filter, Polyhaven (HDRIs + scans).
Handoff
After the organic models are scattered:
Forest scatter ready: 3 species at res://assets/organic/, 100 instances each via MultiMeshInstance3D in ./World/Forest. Next:
- Wind shader (sway in breeze):
summer:vfx/shaders when available, or hand-write a vertex displacement shader.
- Ground texture (grass beneath the trees):
summer:asset-pipeline/asset-strategy Pipeline 2 for tileable ground.
- Lighting / fog (forest mood):
summer:3d-lighting for ambient + directional sun + volumetric fog.
- Ambient audio (forest birds, leaves):
summer:audio/ambient-bed.
- Hero props (a stump, a fallen log, a shrine):
summer:3d-assets/prop-model for the hand-placed standouts.
See also
summer:3d-assets/prop-model — for hand-placed standout pieces.summer:3d-assets/environment-kit — pair with this skill: kit pieces give the architecture, organic gives the natural softness.summer:asset-pipeline/asset-strategy — meta-router; ground textures and skyboxes go to Pipeline 2 / panoramic gen.summer:scene-composition — MultiMeshInstance3D scatter pattern.references/mcp-tools-reference.md — summer_generate_3d schema.
