Design

Ideas

Originally the thumbnailer was part of this project, however since the binary is fairly simple and low level it’s now part of libembroidery. The same is true of the bindings to different languages.

Scheme

Registerables

A scheme registerable should have the form

`cpp pointer name_f(scheme *sc, pointer args); `

where the name of the function is is all lowercase, seperated with underscores, and ending with _f: like_this_f. Note that the _f is present on all scheme registerable function pointers to differentiate them from C functions that aren’t going to be scheme callbacks.

The name of the function in scheme is the same, but with hyphens joining the words like-this-f. Also the -f suffix is present to show that the scheme function has been described in Embroidermodder and is not a TinyScheme built-in or scheme-only function.

After creating the function, add a pointer to the list at the top of the file and add a row to the table ff_list following these rules.

Scheme State

We don’t require that scheme parts of the source don’t create new state entries, however, the state is managed by requiring all state labels are declared in “boot.scm”. For example, we use the context state variable to store what context the current command has been called in. The line:

(define context context-main)

is present in this file to alert programmers that this state variable is present.

Commands

A command is a scheme function designed to be called by a QAction. It may check the context state variable in order to act differently