Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Allow coord grammar to be specified for the color syntax #370

Merged
merged 1 commit into from
Feb 1, 2024
Merged

Allow coord grammar to be specified for the color syntax #370

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
95 changes: 58 additions & 37 deletions src/parse.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,56 @@ import ColorSpace from "./space.js";

const noneTypes = new Set(["<number>", "<percentage>", "<angle>"]);

/**
* Validates the coordinates of a color against a format's coord grammar and
* maps the coordinates to the range or refRange of the coordinates.
* @param {ColorSpace} space - Colorspace the coords are in
* @param {object} format - the format object to validate against
* @param {string} name - the name of the color function. e.g. "oklab" or "color"
* @returns {object[]} - an array of type metadata for each coordinate
*/
function coerceCoords (space, format, name, coords) {
let types = Object.entries(space.coords).map(([id, coordMeta], i) => {
let coordGrammar = format.coordGrammar[i];
let arg = coords[i];
let providedType = arg?.type;

// Find grammar alternative that matches the provided type
// Non-strict equals is intentional because we are comparing w/ string objects
let type;
if (arg.none) {
type = coordGrammar.find(c => noneTypes.has(c));
}
else {
type = coordGrammar.find(c => c == providedType);
}

// Check that each coord conforms to its grammar
if (!type) {
// Type does not exist in the grammar, throw
let coordName = coordMeta.name || id;
throw new TypeError(`${providedType ?? arg.raw} not allowed for ${coordName} in ${name}()`);
}

let fromRange = type.range;

if (providedType === "<percentage>") {
fromRange ||= [0, 1];
}

let toRange = coordMeta.range || coordMeta.refRange;

if (fromRange && toRange) {
coords[i] = util.mapRange(fromRange, toRange, coords[i]);
}

return type;
});

return types;
}


/**
* Convert a CSS Color string to a color object
* @param {string} str
Expand Down Expand Up @@ -40,8 +90,14 @@ export default function parse (str, {meta} = {}) {
// If less <number>s or <percentage>s are provided than parameters that the colorspace takes, the missing parameters default to 0. (This is particularly convenient for multichannel printers where the additional inks are spot colors or varnishes that most colors on the page won’t use.)
const coords = Object.keys(space.coords).map((_, i) => env.parsed.args[i] || 0);

let types;

if (colorSpec.coordGrammar) {
types = coerceCoords(space, colorSpec, "color", coords);
}

if (meta) {
meta.formatId = "color";
Object.assign(meta, {formatId: "color", types});
}

return {spaceId: space.id, coords, alpha};
Expand Down Expand Up @@ -78,42 +134,7 @@ export default function parse (str, {meta} = {}) {
let types;

if (format.coordGrammar) {
types = Object.entries(space.coords).map(([id, coordMeta], i) => {
let coordGrammar = format.coordGrammar[i];
let arg = coords[i];
let providedType = arg?.type;

// Find grammar alternative that matches the provided type
// Non-strict equals is intentional because we are comparing w/ string objects
let type;
if (arg.none) {
type = coordGrammar.find(c => noneTypes.has(c));
}
else {
type = coordGrammar.find(c => c == providedType);
}

// Check that each coord conforms to its grammar
if (!type) {
// Type does not exist in the grammar, throw
let coordName = coordMeta.name || id;
throw new TypeError(`${providedType ?? arg.raw} not allowed for ${coordName} in ${name}()`);
}

let fromRange = type.range;

if (providedType === "<percentage>") {
fromRange ||= [0, 1];
}

let toRange = coordMeta.range || coordMeta.refRange;

if (fromRange && toRange) {
coords[i] = util.mapRange(fromRange, toRange, coords[i]);
}

return type;
});
types = coerceCoords(space, format, name, coords);
}

if (meta) {
Expand Down