blog/skills/concept-art-pipeline.md

Skill: Concept Art Pipeline

End-to-end workflow for creating game character art --- from design brief through 2D concept art to 3D model export. This skill covers everything before the game engine.

Overview

Phase	What	Output
1 --- Design	2D concept art via AI image generation	Approved PNG(s)
2 --- Model	3D generation via Tripo Studio	GLB/FBX export
3 --- Handoff	Reference file for the dev team	Markdown spec

Phase 1: 2D Concept Art

Locking Your Art Style

Before generating anything, define your art style once and enforce it everywhere. Write it down. Here's an example for a stylised game:

• Stylised 3D render, anime-influenced but not full anime
• Matte skin, no metallic sheen, warm earthy tones
• Neutral confident expression --- calm determination, not fierce or smiling
• Earthy palette: browns, tans, dark reds, cream, black
• Asymmetric accessories --- different on left vs right
• Dark grey background for all concept art (consistent, easy to composite)

Hard Rules (define yours)

Every project should have a "do not" list. Examples:

• NO Disney-adjacent designs (if you're going for something grittier)
• NO overly shiny or metallic materials (unless your game's style calls for it)
• NO hair falling forward over chest (won't animate well in-engine)
• NO culturally inappropriate elements (research your references)

Cultural Direction

If your game draws from real cultures, create an approved/rejected table:

Approved	Rejected
Woven natural fibres, shell jewelry	Generic "tribal" patterns
Specific cultural motifs (research them)	Stereotypical elements from wrong cultures
Natural materials (bone, wood, stone)	Modern materials that break the setting

Generation Steps

1. Get the brief --- gender, role, distinctive features, or "surprise me within the style"
2. Generate 3 variants using your image generation tool (see Image Generation skill)
   • T-pose, front view, consistent background
   • Naming convention: character_<name>_front_full_v01.png
3. Score each variant using a rubric (see below)
4. Generate reference sheet for the winner --- front, side, three-quarter, head closeup
5. Save with metadata --- prompt, model used, date, score

Scoring Rubric (0--10)

Score	Meaning	Action
9-10	Perfect match to art style and brief	Approve, generate reference sheet
8	Strong, minor tweaks needed	Approve with notes, iterate once
6-7	Interesting but needs changes	Note what works, regenerate
4-5	Wrong direction, some salvageable elements	Extract what works, fresh prompt
0-3	Off-target	Drop, adjust approach

Score on: style match, cultural accuracy, expression, silhouette (distinctive at distance?), technical (T-pose clean? animatable?)

Layered Design

Design characters in separable layers for future equipment/customisation:

1. Base body --- simple underwear, no accessories
2. Lower garment --- baked into character mesh
3. Upper garment --- baked or swappable
4. Hair --- separate asset (swappable)
5. Accessories --- equipment slots (necklaces, bracelets, headwear)
6. Cape/cloak --- separate equipment piece

Generate the full character for the overall look, but keep separation in mind for 3D.

Phase 2: 3D Model Generation

Using Tripo Studio

Tripo Studio generates 3D models from text or images.

1. Open Tripo Studio
2. Text-to-3D or paste your approved concept art for image-to-3D
3. Use Ultra quality, latest model version, Texture ON (~35-50 credits)
4. Export as GLB (preferred --- preserves PBR textures) or FBX
5. Save to your project's asset pipeline

Tripo outputs ~1.5M faces with full PBR textures (basecolour, normal, ORM). You'll decimate to your target polygon budget in Blender or your engine.

Large Hair Problem

Auto-riggers (like Mixamo) break when the mesh includes big hair --- wrong arm poses, face distortion, rig artifacts.

Rule: For characters with large or complex hair:

• Export a body-only version (no hair) for rigging
• In Tripo: use Segment to split hair from body, export body-only
• Hair is added back as a separate mesh after rigging

Polygon Budget

Define your LOD targets. Example:

LOD	Face Count	Use
LOD0	25,000	Close-up, player character
LOD1	10,000	Medium distance NPCs
LOD2	2,500	Crowd/background characters

Texture QA Checklist

Before handoff, verify:

• PBR textures present --- basecolour, normal, roughness/metallic maps
• No UV seams on prominent areas (face, hands)
• Skin tone matches the approved concept art
• No texture stretching on limbs or torso
• Accessories have distinct materials
• Resolution 2K minimum for hero characters
• No generation artifacts (floating geometry, merged fingers, extra limbs)

Handoff

Create a handoff document for each approved character:

1. Character identity --- name, role, description
2. Concept art files --- paths to approved PNGs
3. 3D model files --- path to GLB/FBX exports
4. Art direction notes --- what to keep, what to change
5. Technical requirements --- shader, rig type, LOD targets, scale
6. Known issues --- large hair flag, texture problems, etc.

Batch Generation

When generating multiple characters:

1. Prepare all briefs upfront
2. Generate in priority order (ship-soonest first)
3. Use free retries before spending credits
4. Score as you go --- don't batch review
5. Track credits per generation
6. Export immediately after approval (don't leave work in the cloud tool)

Common Mistakes

Problem	Cause	Fix
Characters look generic	No art style lock	Define and enforce your style guide
Inconsistent across characters	No reference images	Use your best character as image-to-image reference
Metallic skin sheen	Default material settings	Use matte keywords, check PBR roughness
Symmetric accessories	Generation default	Explicitly describe left vs right in prompt
Auto-rigger fails	Large hair in mesh	Segment and export body-only
Low-poly look in engine	PBR textures missing	Always generate with Texture ON + PBR ON

Related Skills

• Image Generation --- fal.ai Flux models and prompt patterns
• Tripo 3D --- detailed Tripo Studio workflow
• Sora 2 Video --- animate concept art into video