SchOS/docs/branding

Branding

Three marks, three different jobs. They are not interchangeable and the difference is not stylistic.

Shift	the logo	An abstract mark. Non-human, non-animal. Signs the system.
Guru	the icon	A pictogram. Denotes one state. Has a face; has no body.
SchCotie	the mascot	A character. Has a body, poses and expressions.

The distinction that decides everything else: a mascot has to be able to do things. An icon works once, at one size, in one state. A character has to work confused, pleased, asleep and from behind — which is why it costs more and why it is drawn last.

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The one constraint everything answers to

The kernel draws its mark as a 128×128 single-channel coverage mask. include/logo.h holds no colour at all — two pixels per byte, sixteen levels of ink — and the kernel composites it in whatever include/theme.h says.

So any mark that will end up there has to survive as a solid shape in one colour at 128 px, and be recognisable at 24. That rules out hairlines, thin rings and anything that depends on a gradient to read. The mark this replaced failed on all three counts.

Colour is therefore the last decision, never the first. Design the silhouette, then colour it.

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Shift — the logo

shift.svg

Three slabs, displaced: the layer diagram in ../architecture/README.md as a solid object, and the kernel's name (SchIFT) as a shape.

• Any colour. This is a fact about the pipeline, not a preference — the coverage mask carries none, so the loader draws it in metal and the kernel in the theme accent, from the same bytes.
• With or without a wordmark. Set "SchOS" beside it in Roboto Bold, which is already in the tree (ports/Roboto), already Apache-2.0, and already in NOTICE.
• Non-human and non-animal, permanently. The character work belongs to SchCotie; a logo that starts growing a face has taken the mascot's job.

Guru — the icon

guru.svg

The crash face. Mythic rather than cartoon — closer to a temple carving than a character — square or nearly so, with an expression that stays in the :( / :| register.

Purple, and only purple, and only here. theme.h states the rule it enforces:

normal states are calm and dark; only failure is loud. PSOGM keeps the full-bleed purple entirely to itself, which is what makes it mean something.

That purple is PSOGM_BG #4B1D9A, and it is deliberately not the accent #7C5CFF. If Guru ever appears in accent violet on a splash, a sticker or a README header, the deep purple stops meaning the machine stopped — and it is the only colour in the system that means anything at all.

So: Guru does not leave the crash screen.

SchCotie — the mascot

Not drawn yet.

A daemon: the process that works while nobody is watching. The horns are a pun on the word; the meaning is the background job that keeps running after you have walked away — which is schinit supervising, restarting what dies, awake at 3am. Patient and watchful rather than mischievous.

Horns carry X — POSIX, Unix, X11 — one substitution reading three ways.

Two constraints that follow from the section above. A thin X is two diagonal strokes and dissolves at small sizes, so it wants to be solid wedges with the X notched out as negative space: the horn silhouette survives downscaling and the X appears as you get closer. And it needs a turnaround — front, side, three-quarter, matching heights on shared construction lines — because a character drawn once at one angle only ever works at that angle.

The licensing point, which is not optional here

The BSD daemon is copyrighted. Marshall Kirk McKusick holds it and the terms are not a free licence. A character that reads as "Beastie, but purple, with X horns" is a derivative-work argument, and this mark would be in every image SchOS ships, beside a NOTICE file this project has been careful about.

The concept is not the problem. A daemon is a Greek daimon and a Unix background process — neither is ownable. What belongs to Beastie is the execution: the pitchfork, the sneakers, that red, that face, that pose. Horns, a tail and a small imp are generic and thousands of years old.

Draw from the idea. Do not have a picture of Beastie open while you do it.

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Colour

From include/theme.h, which is the source of truth. Nothing here restates a value it does not already define.

SCH_BG	#0C0E13	Ground. Near-black with a blue cast, because pure black reads as "switched off".
SCH_FG	#E6E8EC	Primary text
SCH_DIM	#707784	Secondary
SCH_ACCENT	#7C5CFF	The one accent. Shift, SchCotie, anything calm.
PSOGM_BG	#4B1D9A	Failure only. Guru's ground and nothing else's.

File formats

SVG, or PNG at high resolution with no lossy compression. Nothing else.

No JPEG anywhere — a mark is flat colour with hard edges, which is the exact case JPEG is worst at, and the ringing it leaves around an edge is permanent. No screenshots of marks. No re-exports of re-exports: go back to the SVG.

SVG is the source of truth for every mark. A raster is something generated from it, never edited.

What is in here, and why a raster is committed

shift.svg               the logo, in colour
shift-mask.svg          the same geometry in greys -- see below
shift-mask.png          rasterised from it, committed on purpose
uberblock.svg           SchFS
guru.svg                the crash icon
superseded-*.png        the old wordmark, kept for reference only

The pipeline is three stages:

shift-mask.svg  --(inkscape)-->  shift-mask.png  --(make logo)-->  include/logo.h

Both intermediates are committed, and that is deliberate. inkscape is not a build prerequisite — see ../guides/building.md — so a build that required a vector rasteriser would stop working on most hosts for the sake of a file that changes about once a year. The PNG is regenerated by hand when the SVG changes, and make logo turns it into the header.

Why the mask is a separate file from the logo

tools/python/mklogo.py reads ink as (255 - luminance) * alpha, so tones survive as coverage rather than being flattened — and the relationship inverts: darkest here is brightest on screen. Copying the violet fills from shift.svg would light the object from below.

So shift-mask.svg is the same geometry in greys chosen for how the mask reads. Two files sharing one geometry is a drift hazard; the <desc> in both says so. If either is edited, edit both.

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Where each mark is actually drawn

Loader splash	Shift, from include/logo.h, shaded per row by metal() in boot/common/ui.c — silver, not accent.
Kernel console / early boot	Shift, same mask, composited flat in a theme colour by gfx_draw_logo.
PSOGM	Guru, drawn from primitives by draw_guru() in kernel/core/panic.c. Never a bitmap: it scales with the display and costs nothing in the kernel image.
Serial crash report	:(, as text. Guru cannot be drawn in ASCII, and a mood marker in a log is not the icon.
SchFS	Nowhere yet. uberblock.svg has no consumer; it is waiting for projects/schfs-linux/ to have a README worth heading.

One trap, since it has already been stepped in: boot/common/ui.c includes logo.h, theme.h and font.h, and the Makefile rule for the loader did not list them. A new logo therefore did not rebuild the loader — make reported nothing to do and the splash kept drawing a mask compiled months earlier. The kernel half never showed the problem because those objects are built with -MD -MP and track their own headers. Changing anything in here means the loader must actually relink, and that needs clang and lld-link.

What this does not cover

• No trademark position. These are marks the project uses, not marks anyone has registered or defended.
• No usage rules for third parties — nothing says what someone else may do with them. Worth writing before anything is published.
• SchCotie does not exist. Everything above it is a brief, not a description.
• Guru is drawn but not wired in. panic.c still renders :( from primitives, and there is a real argument for keeping it — see the note in that file about being "legible as a mood without being a picture of anything".
• No wordmark lockup is specified. "Roboto Bold beside it" is not a spacing rule, a size ratio or a clear-space margin, and it will want to be.