Schematic Topographic

Schematic Topographic draws a full cartographic sheet over an image - contour lines, heavier index contours with elevation numbers rotated along the line, depression hachures, spot heights, benchmarks, slope arrows, a coordinate grid, a north arrow, a scale bar. The map-poster look, in milliseconds, on the CPU, with no model and no diffusion pass.

That's why it deserves a slot. Almost every "make it look designed" move in ComfyUI is a generative re-pass: you pay a sampler and gamble on the model not repainting what you liked. This is the other layer - deterministic vector work, wrapped as a node (post-processing.md).

Read this before you turn any dial

By default, the terrain has nothing to do with your photo. height_source defaults to procedural: a seeded fractal landform built from seed, terrain_scale, terrain_octaves, terrain_roughness, terrain_stretch and terrain_angle. The sheet lies over the picture like tracing paper. If you wanted contours that trace a face or a mountain, that's brightness, darkness or detail - or wire a mask into the optional height_mask, which replaces the terrain entirely (white = high ground).

Nudge terrain_scale for ten minutes and the photo still won't change. It was never read.

How it works

The source becomes a height field normalised to 0–1, then Gaussian-blurred by smoothing (sigma in px - your "how calm is the terrain" dial; 0 leaves raw noisy pixels). It's resampled onto a coarser grid at one sample per contour_resolution pixels, and a marching-squares tracer walks that grid at every level z = k × contour_interval between elevation_min and elevation_max, chaining segments into polylines. Every index_every-th level - counted in absolute metres, so 200/400/600 m at 40 m × 5 - is drawn heavier and labelled. Drawing is Pillow at 2× supersampling, which is why strokes come out clean rather than jaggy, and each element has its own seeded random stream, so switching benchmarks off doesn't re-roll your spot heights.

The settings you'll actually touch

Terrain shape first. terrain_scale (420) is the size of the largest landforms in px; terrain_stretch and terrain_angle are what sell it, stretching blobs into ridges and valleys flowing one direction, while terrain_octaves and terrain_roughness add finer wrinkles.

Then density. contour_interval is metres between lines, and the tooltip's arithmetic is the clearest spec you'll get: 0–1000 m at 40 m is 24 lines, at 20 m is 49. If the sheet reads as grey mush, raise the interval first.

Two more worth knowing. contour_text runs a string along the contours glyph by glyph, following the line - the calendar-poster device, a name spelled across the hillsides - with contour_text_on choosing index contours only or all of them. And image_opacity defaults to 0.85, not 1.0 - the photo is deliberately faded under the sheet, so push it to 1.0 if you want the picture to fight the map. map_scale (metres per canvas px) wants a physical value as well; at the default of 1, grid labels are pixel numbers wearing a metre hat.

Outputs

image is the finished composite - background, photo, hypsometric band tone, vector stack, grain - and goes to a SaveImage node. overlay_only is that vector layer minus the photo. overlay_alpha is a 0–1 mask of everywhere ink was drawn, and it's the one people forget: feed it to a downstream mask input to grade or blur only where the map sits. Batches get a sheet per frame from the same terrain, so animation contours stay locked; height_mask and texture use frame 0 for the whole batch.

Install

Nothing to download. ComfyUI Manager → search "ComfyUI Schematic" → install, or:

cd ComfyUI/custom_nodes
git clone https://github.com/jeremieLouvaert/ComfyUI-Schematic

Restart ComfyUI; the node shows up under AKURATE/Schematic. The pack's requirements.txt is Pillow>=9.0, which you already have. No scipy, no models, fonts bundled in the repo - nothing to pin, nothing to break (comfyui-ecosystem.md).

Where people get burned

A flat height field renders contour-free. Push a uniform image through brightness and the node logs a notice and skips every contour, hachure, arrow, spot and benchmark. No levels to trace, so nothing to draw.

Levels cap at 400. A tiny interval across a wide elevation range trips the guard and prints "level cap 400 reached, raise contour_interval" to the console.

Labels need room. At label_spacing 320 px, index contours shorter than that get no elevation label, so small features end up bare. And index_every at 0 means no index contours - hence no labels, and nothing for contour_text to ride on in index mode. Related: if elevation_max ≤ elevation_min the node swaps them and logs it, so you get a sheet, just not the one you asked for.

Cost scales with canvas. contour_resolution 2 is indistinguishable from 1 at default smoothing and twice as fast - stay there unless you're printing. On mixed-resolution batches, size_preset cover-fits every frame to one canvas.