FL Grad Generator

A proper multi-stop gradient generator, driven by a small JSON spec rather than a fixed two-color picker. Useful for backgrounds, for masks-as-gradients in lighting or depth effects - feed one straight into FL_DepthBlur's depth_map input for a synthetic linear "depth," for instance - or just as a clean base layer to composite onto.

The mechanism

gradient_colors takes a JSON array of color stops, each specifying a position along the gradient and a color value - the field is exposed as a raw STRING, default "[]" (an empty spec), so you're writing or generating that JSON yourself; this pack doesn't ship a GUI color-stop editor for it the way some dedicated gradient tools do. color_mode picks whether interpolation between stops happens in RGB space or HSV space. This matters most when stops are far apart in hue: RGB blending two saturated, opposite-hue colors muddies through gray in the middle, while HSV blending can sweep around the color wheel instead and stay vivid the whole way. interpolation (Linear / Ease In / Ease Out / Ease In-Out) shapes the transition curve between stops the same way an animation easing curve would - Linear is a flat ramp, the Ease variants bunch the transition toward one or both ends.

Inputs and outputs that matter

width and height (64-4096 each, default 512x512) set the output canvas size. color_mode, interpolation, and gradient_colors control the actual gradient - gradient_colors is where the content of the gradient lives.

Output: a single IMAGE.

Installing it

ComfyUI Manager: search Fill-Nodes, install, restart. Manually: cd ComfyUI/custom_nodes && git clone https://github.com/filliptm/ComfyUI_Fill-Nodes, then restart. No external dependencies beyond what the rest of the pack already needs.

Where people get burned

This node is filed under the pack's own "experiments" category - the author's own signal that it's less polished and stable than the main sections, worth calibrating expectations accordingly.

The bigger practical trap is gradient_colors itself: it's a raw JSON string with no on-node validation UI, so a malformed stop list - a missing position, a bad color format - is going to fail or produce something unexpected rather than give you a friendly error pointing at the mistake. Build and test the JSON in a small snippet before wiring it into a bigger graph, and keep a known-good example around to copy from rather than hand-writing it fresh each time.