texel-studio

Texel Studio

The only pixel art tool that actually paints like a real artist.

Every other AI pixel art generator is a diffusion model pretending to understand pixels. They output blurry approximations — inconsistent colors, broken edges, half-pixel artifacts, and results that look different every time you run the same prompt. They don't understand what a pixel is.

Texel Studio is different. An AI agent picks up a brush, places pixels on a canvas one at a time, steps back to look at what it drew, and decides what to fix. It uses shapes, noise fills, and detail tools — the same way a human pixel artist works. Every pixel is intentional. Every color is from your palette. The output is exact, consistent, and game-ready.

This is the open-source engine that powers texel.studio.

https://github.com/user-attachments/assets/63e2fdde-3f15-4ffd-8b27-60acaef9a9c5

How it works

1. Describe what you want ("a mossy cobblestone block")
2. Generate concept art — AI creates a reference image for guidance
3. Confirm the reference (or revise with feedback)
4. Watch the agent paint — it uses drawing tools to build the sprite step by step
5. Chat to edit — tell the agent "make the top darker" and it continues painting
6. Export — native size PNG, upscaled 512px, or full autotile tileset (16 variants)

Why not diffusion?

	Diffusion generators	Texel Studio
Output	Blurry approximation scaled down	Exact palette-indexed pixels
Colors	Random, needs post-processing	Your palette, every time
Consistency	Different result every run	Deterministic tool calls
Edges	Anti-aliased, half-pixels	Clean, game-ready edges
Control	Prompt and pray	Chat to refine, pixel by pixel
Process	Black box	Watch it paint, step by step
Tileable	Almost never	Built-in autotile generation

Diffusion models hallucinate pixels. This tool places them.

Agent Tools

Drawing

• draw_pixel, draw_pixels — individual pixels
• fill_rect, fill_row, fill_column — rectangular fills
• draw_line — Bresenham lines
• draw_circle, draw_ellipse — round shapes (filled or outline)
• draw_triangle — filled triangles
• draw_rotated_rect — angled rectangles

Texture

• noise_fill_rect, noise_fill_circle — random color distribution for natural variation
• voronoi_fill — cell/stone patterns (cobblestone, rocks, organic surfaces)

Inspection

• view_canvas — see current pixel grid + color usage
• get_pixel — check a single pixel value

Features

• Sprite types — Block (tileable) and Item Icon (transparent bg) with type-specific prompts
• Multi-provider — Gemini, OpenAI, and local Ollama models (100% free with Ollama)
• Concept art reference — AI generates a reference image before pixel painting
• Live streaming — watch the sprite build in real-time via SSE
• Chat continuation — send follow-up edits to the same agent session
• Manual pixel editing — click to paint, right-click to erase
• Palette management — create, edit, and reuse color palettes
• Autotile generation — generate all 16 edge variants for tilemap use
• Export — native PNG, upscaled preview, or full tileset folder
• History — browse and reload past generations
• S3 storage — optional S3-compatible object storage for shared file access across workers
• Observability — optional LangSmith and/or PostHog LLM analytics tracing

Setup

git clone https://github.com/EYamanS/texel-studio.git
cd texel-studio

# Quick start (handles everything)
./start.sh

# Or set up manually:
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt
cp .env.example .env       # edit with your API key(s)
cd frontend && npm install && npm run build && cd ..
python server.py

Open http://localhost:8500

Authentication

You need at least one AI provider configured:

Ollama (free, runs locally)

• Install Ollama and pull a model:

  ollama pull ggml-org/gemma-4-E4B-it-GGUF:Q8_0
  

• Add to .env:

  OLLAMA_MODELS=ggml-org/gemma-4-E4B-it-GGUF:Q8_0
  # OLLAMA_URL=http://localhost:11434   # default, only set if different
  

• That's it — no API keys, no accounts, no cost. The model runs on your machine.
• You can list multiple models: OLLAMA_MODELS=gemma-4:8b,llama3.1:8b,qwen3:8b
• Recommended models for pixel art: ggml-org/gemma-4-E4B-it-GGUF:Q8_0, qwen3:8b, llama3.1:8b

Gemini (for both concept art + agent painting)

• Get a free API key at aistudio.google.com
• Add GEMINI_API_KEY=your_key to .env
• Or use a Google Cloud service account for Vertex AI

OpenAI (agent painting only, concept art still uses Gemini)

• Add OPENAI_API_KEY=your_key to .env

OpenAI-compatible servers (Llama.cpp, VLLM, LM Studio, OpenRouter, etc.)

• Point at any OpenAI-compatible endpoint and register the model names you want in the UI:

  OPENAI_BASE_URL=http://localhost:8080/v1
  OPENAI_MODELS=llama-3.1-8b-instruct,qwen2.5-coder-7b
  # OPENAI_API_KEY=optional_for_local_servers   # required for hosted ones like OpenRouter
  

• Models listed in OPENAI_MODELS appear in the model dropdown alongside the built-in OpenAI models.

All providers can be configured simultaneously — choose the model per generation in the UI.

Want to run 100% free? Install Ollama, pull a model, set OLLAMA_MODELS in .env, and you're done. No API keys needed. Concept art generation requires Gemini, but you can skip it and paint directly.

Autotile Export

After generating a block sprite, click "Generate Tileset" to create all 16 autotile variants:

• Edge darkening on exposed sides
• Outline on exposed edges
• Rounded corners where two exposed edges meet

Output: BlockName_00.png through BlockName_15.png

Scaling (Optional)

For concurrent generation support, add Redis and run workers:

# Set in .env — must be Redis Stack (RediSearch module enabled),
# not vanilla Redis. The LangGraph checkpointer needs FT.* commands.
REDIS_URL=redis://localhost:6379

# Local dev: run Redis Stack via Docker
docker run -d --name texel-redis -p 6379:6379 redis/redis-stack-server:latest

# Run the API server + worker(s)
python server.py &
python worker.py &
python worker.py &  # add more workers for more parallelism

Workers pull jobs from a Redis queue, publish progress via pub/sub, and persist LangGraph thread state via RedisSaver. Any worker can resume any chat — no per-worker affinity. Vanilla Redis won't work because the checkpointer requires the search module; use Redis Stack, Redis Cloud, or a self-hosted Redis with redisearch enabled.

Without REDIS_URL, the engine runs single-process with an in-memory MemorySaver checkpointer — fine for personal use.

Storage (Optional)

By default, generated images and references are saved to the local filesystem. For multi-worker deployments where workers run on separate machines, configure S3-compatible object storage:

# Set in .env — works with AWS S3, Railway Object Store, Cloudflare R2, MinIO, etc.
ENDPOINT=https://your-s3-endpoint
ACCESS_KEY_ID=your_key
SECRET_ACCESS_KEY=your_secret
BUCKET=your_bucket

Without these, everything uses the local filesystem.

Extending — adding a new job kind

The engine has a generic Job abstraction. Every operation the agent does (generate, chat, reference, tileset, photo→pixel) is registered against a kind string. Adding a new kind is one file:

# jobs/my_thing.py
from pydantic import BaseModel
from . import JobHandler, JobContext, register_job, log, result

class MyParams(BaseModel):
    prompt: str
    size: int = 16

@register_job("my.thing")
class MyHandler(JobHandler):
    Params = MyParams

    def run(self, params: MyParams, ctx: JobContext):
        yield log("Doing the thing...")
        # ... do work, optionally yield progress(...) events ...
        yield result(status="completed", payload={"hello": "world"})

Then import it once at startup (e.g. add from . import my_thing to jobs/__init__.py:_load_builtins). The dispatcher picks it up automatically.

Drive it from anywhere:

curl -N -X POST http://localhost:8500/api/jobs \
  -H "Content-Type: application/json" \
  -d '{"kind":"my.thing","params":{"prompt":"hi","size":32}}'

The same endpoint works in self-hosted (in-process) and queued (Redis) modes. Built-in kinds:

Kind	What it does
sprite.generate	AI-paints a sprite from a prompt
sprite.chat	Continues editing an existing sprite via chat
sprite.reference	Generates concept art (Gemini image gen)
sprite.tileset	Builds the 16-variant autotile from a base sprite
sprite.from_photo	Quantizes a photo to the chosen palette

GET /api/jobs/kinds returns the list at runtime.

Observability (Optional)

LangSmith — LangChain's tracing platform:

LANGSMITH_TRACING=true
LANGSMITH_API_KEY=your_key
LANGSMITH_PROJECT=texel-studio

PostHog LLM Analytics — traces, token counts, latency, costs:

POSTHOG_API_KEY=phc_your_key
POSTHOG_HOST=https://us.i.posthog.com

Both can run in parallel. Neither is required.

Cloud Version — texel.studio

Don't want to self-host? The cloud version is ready to use:

• Sign up and start creating — no API keys, no setup, no Python
• 5 free credits daily — no credit card required
• Pro plan — $9/month for 200 credits with rollover
• Credit packs — buy 100, 250, or 700 credits anytime
• Per-user palettes — create, edit, share to a public gallery
• Generation history — saved to your account, pick up where you left off
• Shared gallery — browse and copy other users' sprites and palettes

The cloud runs this same engine on Railway with Redis workers, Supabase for auth and data, and Polar.sh for billing. The generation quality is identical — the cloud just removes the friction.

Start creating at texel.studio →

Tech Stack

• Backend: Python, FastAPI, LangGraph, LangChain
• AI: Google Gemini + OpenAI + Ollama (pluggable, run free with local models)
• Frontend: Next.js (static export to static/)
• Queue: Redis (optional, for concurrent generations)
• Storage: S3-compatible (optional, for multi-worker file sharing)
• Tracing: LangSmith + PostHog (optional)

Support

Built this in the open. If it saved you time, a one-off tip keeps it maintained:

License

Source-available. Use it freely — self-host, modify, use commercially, sell anything you generate. The only restriction: don't host it as a competing SaaS. See LICENSE.

---

Built by Emir Yaman Sivrikaya

Keywords: AI pixel art generator · text to pixel art · pixel art AI · sprite generator · game asset generator · pixel-art tool · AI sprite art · generate pixel art from a prompt.