Values & palettes
Values and colour are where a scene most often drifts from its concept. Limner shows both directly in the viewport, for the whole frame, while you light and dress the scene.
Viewport views
Section titled “Viewport views”The view buttons in the viewport bar apply to the whole viewport, the scene and the overlay together:
| View | Shows |
|---|---|
| Color | The viewport as it is. |
| Values | Lightness only: the squint test for values. |
| Notan | Lightness posterized into 2 to 5 value bands: the big shapes of light and dark. |
| Off-palette | Magenta where a colour is far from every palette colour. |
The views are drawn after tone mapping, so exposure, color grading and post process count, as they do for the player.
Values
Section titled “Values”Values shows the scene in grey by its lightness (CIE luminance). Colours of the same lightness look the same, so you see whether the focal point stands out by value or only by colour. Compare it with the reference in Values, or in Difference mode.
Notan splits the lightness into equal bands and paints each band in one grey: with 3 bands, everything below L* 33 is black, everything above L* 67 is white and the rest is mid grey. Set the number of bands with Bands in the viewport bar (2 to 5; 3 by default, from Value Bands in the settings).
A good composition usually reads in 2 or 3 bands: a few large, simple shapes. Many small scattered patches in Notan mean the values are busy.
Palettes
Section titled “Palettes”Extract a palette
Section titled “Extract a palette”Select an image on the board and click Extract palette in the inspector (or in its … menu). Limner finds the image’s main colours and shows them as swatches with their share of the image; hover a swatch for its hex code and share. Extract again replaces the palette.
The number of colours comes from Palette Size in the settings (6 by default, 2 to 12). The result is the same every time for the same image. Transparent pixels are ignored.
Palettes are found by k-means clustering in Lab colour space, so colours that look alike are grouped the way the eye groups them.
The key palette
Section titled “The key palette”Click Use as key to make an image’s palette the board’s key palette: the colours the whole level should follow. The board inspector (nothing selected) shows it, with Clear key palette.
| Palette used by | With a key palette | Without one |
|---|---|---|
| Off-palette view | The key palette | The active reference’s palette |
| Compare | The key palette | The compared reference’s palette (extracted on the fly if it has none) |
| Palette check (Vision menu) | The key palette | The active reference’s palette |
To check whether the colours of a palette stay apart for colour-blind players, use the palette check of the colour vision preview.
Off-palette view
Section titled “Off-palette view”Off-palette paints every pixel magenta whose colour is far from all palette colours, stronger the further away it is, and desaturates the rest so the magenta stands out. A colour counts as close when its difference to a palette colour (CIE76 delta E) is at most Palette Tolerance (22 by default). Without a palette, the view shows nothing.
Use it to find the stray saturated light, the wrong-coloured prop or the fog that turned green.
Without a viewport
Section titled “Without a viewport”From Python, extract_palette_from_file() reads the palette of an image file and write_value_image() writes a grayscale or notan version of it. Both work without a level, for example on a build machine. See Python.