Upload art & auto-cut layers

The fastest way into Charios. Drop your character art onto the editor canvas; we cut every body part out of the alpha channel and snap each one to the right bone. If the auto-snap got something wrong, drag the layer onto the right bone — that's all the rigging there is.

Layers vs Character Image

When you click the Upload pill at the top of the canvas, there are two paths. They produce the same result; pick whichever matches the art you have.

Layers

Drop one or more PNGs, each containing one or more body parts. This is what you'll use most often — your character was drawn in Photoshop / Procreate / Krita with each body part on a separate layer, and you've exported each as a transparent PNG.

Charios reads the alpha channel of each PNG, finds every "island" of opaque pixels, and shows them as candidate crops. You confirm which ones to keep, and each one becomes a layer in the editor, snapped to its nearest bone.

Character Image

Drop a single composite character — a fully painted humanoid drawn as one image. Same alpha-cut flow, but Charios runs an AI background-cleanup pass first if the image looks photo-y. This is the path most users take when their character was generated by Midjourney, DALL·E, Stable Diffusion, or another AI image tool.

How auto-cut works

Charios scans the image's alpha channel for connected regions of opaque pixels — what we call alpha-islands. Each island becomes a candidate crop. The threshold is generous (alpha > 16 / 255) so thin outlines don't get clipped, and very small specks (< 64 pixels) are ignored to skip JPEG compression noise around the edges.

After confirming, each island becomes a LayerDoc in your project — a sprite parented to a bone. The bone is picked by computing the centroid of the island and choosing the closest bone segment. "Closest" is Euclidean distance on the canvas, so a glove dropped near the wrist snaps to the hand bone, a sword dropped near the elbow snaps to the sword bone, and so on.

If the auto-snap got it wrong

Sometimes auto-snap puts a sprite on the wrong bone. Most often this is the sword (which lives at the elbow → wrist segment alongside the right forearm) ending up on the forearm bone. To fix it:

1. Open the layer panel (left side of the editor).
2. Find the sprite under the bone it landed on.
3. Drag the sprite row onto the bone row you actually want — it'll reparent immediately.
4. Charios recomputes the bone-local position so the on-screen position doesn't change. The sprite stays where it was visually, but now follows the new bone when animating.

Need a custom crop?

If auto-cut produces an island that's too aggressive (say it merged the chest + belt buckle into one), hold Shift and drag a rectangle on the upload preview to draw a custom crop. The custom crop participates in the bone-snap exactly like an auto crop.

After uploading

• Apply an animation: Browse the mocap library.
• Adjust the layer stack: Understand layers & the bone rig.
• Tweak proportions: Adjust body shape & proportions.
• Generate alternate looks: Generate AI variants.