rodeo_screen.h

Generated from the header

This page is rodeo-sdk/common/rodeo_screen.h — its comments and declarations. To change it, change the header.

The platform’s display is a 128x64 SSD130x (see oled_ssd130x_bulk.h), so the geometry here is the platform’s, not any one instrument’s: 21 characters of Font_6x8 across, five list rows under a title bar. An instrument supplies its own layout constants and its own Draw(); these are the pieces every list screen on this hardware ends up needing.

TEMPLATED ON THE DISPLAY, which is what lets these render on a laptop as well as on the board: libDaisy’s OledDisplay is a template over its driver and everything under it is plain C++, so a stub driver holding a framebuffer gives pixel-exact screens with nothing flashed. See firmware/tools/screens.

Written for rodeo-002 and moved here on 2026-10-01.

NOTHING WRAPS ON THIS DISPLAY: a string longer than its room draws straight over whatever is beside it. That is why AppendUpTo exists and why every field goes in through it.

kListTop

constexpr int kListTop = 12;

The list convention on a 128x64 panel: a 10-pixel title bar, then five rows of 6x8 on a 10-pixel pitch. An instrument may ignore these and lay out its own screen; a list screen almost never wants to.

kRowPitch

constexpr int kRowPitch = 10;

kListRows

constexpr int kListRows = 5;

kChar

constexpr int kChar = 6;

Font_6x8 is the header’s font, so a character is six pixels and the line holds twenty-one of them. Spelled once, because the header now packs two fields against each other and every number here is derived from it.

AppendUpTo

template <size_t kCap> static void AppendUpTo(FixedCapStr<kCap>& s, const char* text, int room);

Append what fits and no more.

Nothing wraps on this display: a string longer than its room draws straight over whatever is to its right. Every header field is bounded by what the field beside it leaves, so every one of them goes in through here.

DrawTitle

template <typename Display> static void DrawTitle(Display& display, const char* text, const char* right);

A title bar: inverted, with an optional counter on the right.

DrawRow

template <typename Display> static void DrawRow(Display& display, int r, const char* left, const char* right, bool selected);

One list row. The selected row inverts rather than carrying a marker, which would eat a character of width on a 21-character line.

DrawScrollBar

template <typename Display> static void DrawScrollBar(Display& display, int first, int visible, int total, int y0 = kListTop, int track = kListRows * kRowPitch - (kRowPitch - 8));

How far down a long list you are. Nothing is drawn when it all fits.