BD Mask Color Fill

BD Mask Color Fill takes up to four masks and fills each with a solid color, then composites the whole thing over a background. That's the entire job, and the entire reason it exists is to build flat-color zone textures - most visibly the 2D flipbook UV textures in this pack's face pipeline, where you take BD Face Socket Infill mask outputs and turn them into clean, color-coded regions a game shader can read.

The mental model: each of the four slots is a colored rubber stamp. Wire a MASK into mask_1, pick its RGB with r_1/g_1/b_1, and the node stamps that color wherever the mask is white. Slots layer bottom-to-top - slot 1 is painted first, slot 4 last - so where two regions overlap, the higher-numbered slot wins. Leave a slot unwired and it's simply skipped, which means "up to four" is "however many you need."

The inputs that matter

• expand_1 … expand_4 - dilate each mask before coloring. Grow the painted region outward by N pixels. This is how you close the little gaps between zones that the source masks left behind.
• feather_1 … feather_4 - soften the stamp's edge. Positive feathers outward from the fill edge (interior stays opaque, boundary bleeds out); negative feathers inward (the fill fades toward its own edge); 0 is a hard binary edge. Per-slot, so a hard eye region can sit next to a soft hair region in the same pass.
• background - if you connect an image here, it's used as the base instead of the bg_r/bg_g/bg_b solid color. This is where the composite gets real: paint your zones over the actual character render.

Then there are two clipping controls that turn "paint rectangles" into "paint the head":

• bg_mask - a clip mask applied after all slot painting, ComfyUI convention (white = keep/opaque, black = transparent). Wire your head silhouette here and anything a slot painted outside the head gets cut away. This is the recommended way to clip by head shape - the README is explicit about it.
• bg_alpha_from_image - when ON with a background image connected, the background's luminance drives the alpha channel: white background pixels become opaque, black become transparent. Pair with bg_alpha_invert if your image uses the opposite convention (white = background to cut out). This is your "background is already a cutout shape" mode.

Outputs

You get three views of the same result: image (RGB composite), rgba (filled regions opaque, background transparent unless you raised bg_alpha), and mask (the union of all active slots - handy if you want the total painted footprint as a mask for something downstream).

A usage note

The classic setup in this pack: BD Face Socket Infill outputs per-zone masks → four of them into BD Mask Color Fill with different colors → rgba out to a texture-save node. It's also a perfectly good general "colorize these regions" node for any mask set, and the per-slot expand/feather is what keeps hand-built masks from looking like hand-built masks.

Installing

Standard BrainDead pack install - ComfyUI Manager search "BrainDead", or clone + pip install -r requirements.txt + restart. All V3 API, so keep ComfyUI updated.

One habit worth picking up: when zones bleed where they shouldn't, the fix order is bg_mask first (clip by shape), then per-slot expand to close gaps, then feather to blend seams. Skip ahead to feathering before clipping and you'll just be softening the spill you meant to remove.