Scenario Zbrush Paint Render

ZBrush paint and render (texture and presentation artist)

Expert paint in ZBrush is observation made systematic: color zones placed by what lies under the skin, pushed enough to survive the shader, judged on neutral and flat views, and baked at a resolution the mesh can hold. For an agent without a tablet most of it is buttons: fills at a chosen intensity through generated masks, zone images projected onto the mesh, and renders that are both measured and looked at. If a sibling skill named here is missing from your available skills, ask the user to install it (npx skills add scenario-labs/skills --skill <name>); unattended, proceed from tool schemas and flag the gap.

REQUIRED BACKGROUND: scenario-zbrush-expert (bridge, stroke engine, review loop, 2026 traps).

Stance (the expert delta)

• Paint last, at the top level. Polypaint is one color per vertex: a lower level paints blurry, adding levels afterwards breaks it, and the map follows the point count (about 4M points per 2K map; 4K is wasted there) (FlippedNormals).
• Judge on neutral and flat. SkinShade4 or MatCap White01, plus Flat Color. A tinted MatCap makes you overcompensate and the export looks wrong elsewhere (FlippedNormals, Pablo).
• Structure before beauty. Start with a pure yellow, red and blue zone map placed by anatomy: bone and fat yellow, thin tissue red, hollows blue, more blue low on a man. Then cover it with skin color at low opacity so the zones shimmer through (Pablo). For an agent this is also the route that can be checked in numbers.
• Masks are "the real trick" (Pablo): generator, Mask Adjust, Inverse, color through the mask. The agent's big soft brush is FillObject at low RGB Intensity through the inverted mask: it scales with RGB Intensity (FlippedNormals), Pavlovich fills through an inverted AO mask, and the tooltip reads "Fill 3D Object Masked".
• Saturation is the stylization dial (Pablo); paint to be diluted (FlippedNormals). Shaders wash polypaint out. Pick the final renderer before deciding how far to push, and keep realistic skin under the middle of the picker.
• Contrast directs the eye. The strongest value or saturation contrast goes to the eyes, and the eyes and mouth get the most time (FlippedNormals).
• Small and fast, then big and slow (Pavlovich). Test small at a high Error Threshold, compare renders side by side, and rebuild the beauty from passes instead of re-rendering.
• Visibility traps (Maxon docs). A displayed texture hides polypaint. In Redshift only Polypaint materials show paint (Use Material Color 0, white Base), SSS Weight 1 hides it, and MatCaps show no texture.

Establish first

Workflow

Toolkit: scripts/zb_paint.py, ZBrush-side functions through zp.remote("name", ...); full code in references/procedures.md. Save a versioned ZTL after every stage: there is no undo control.

1. Preflight. paint_state() (level, points, UVs, texture display), recommend_map_size(points), texture_off(), save a ZTL. GATE: top level, map_budget(points, side) passes, v001 on disk. Divide now if needed, never after painting.
2. Setup and base. set_paint_mode("rgb") (Zadd and Zsub off), fill(colour, 100): a dull skin base (FlippedNormals, doc) or pure yellow for the zone route (Pablo). GATE: the Flat front shows the fill color; Colorize reads on.
3. Zone map. Parts (eyes, scarf, teeth, clothes): fill_subtools. Polygroups: review with polypaint_from_polygroups(), fill exactly with zone_fill_by_split() (Duplicate, Groups Split, fill each piece, Project All back with Colorize on). Anatomy on one mesh: skin_zone_plan → zone_image → polypaint_from_image (planar UVs, before real UVs); synthesized Color Spray strokes as the fallback. GATE: skin_zone_checks(stage="zones"): forehead yellower than midface, midface redder, a man's lower third bluer, each by at least one JND (2.3 Lab); visually a clown on purpose (Pablo), every zone on its anatomy.
4. Cover and breakup. Skin color at 20 to 40 percent over the zones (doc RGB about 30; Pablo's low-opacity cover); breakup from zone-image noise or Color Spray strokes. GATE: stage="covered": no clown (at most 5 percent of skin pixels above saturation 0.75 [added]), speckle present.
5. Mask passes with mask_pass: cavity darker and redder at 20 to 40 percent; PeaksAndValleys (PVRange 14) or Smoothness with a pale warm fill; ao_plugin mask with a purple-red undertone (ping after). Pablo's Adjust Colors is a dialog [verify live_p06]; a low fill through the same mask replaces it. Mask data cannot be read: prove a mask with mask_coverage(masked, cleared). GATE: each pass shifts the region statistics a little, together they read as skin, back of the head included.
6. Focus and finish. Eyes: an iris image (dark ring, lighter bottom, darker top, lighter toward the pupil) projected onto the eye SubTool, then slight divergence; lips; selective darkening only where light never reaches unless the renderer adds no AO; a 5 to 10 percent wash for realism. GATE: final skin_zone_checks with eye contrast, then the Flat, SkinShade4 and MatCap White01 sheets (paint_review) judged with references/critique.md.
7. Deliver the color. texture_from_polypaint(path, side, flip_v=True) needs UVs (UV Master on a clone, Paste UVs keeps polypaint); or OBJ vertex color; or Substance Bridge Send PolyPaint. GATE: map budget passes, an asymmetric mark lands where expected, file on disk.
8. Render. Save, set_document_size (small for tests; Resize clears the canvas, the function redraws), render_setup (perspective, shadows, AO), bpr_render or paint_views(..., "bpr") for matched views. GATE: render_checks pass and the renders were looked at at 100 percent.
9. Passes and turntable. export_bpr_pass (may open a dialog); clown pass by subtool_solo_views plus id_pass (paint and polygroups untouched); composite (shadow and AO Multiply through the mask); turntable_frames in short chunks, assemble_turntable. GATE: every frame upright with constant framing; the composite beats the beauty toggled against it.
10. Portfolio and report. Gray form views (colorize_all(False), zb_review.review, restore), albedo and beauty views, ID pass, turntable, one sheet. Report what was measured, what was only looked at, what did not run.