imagerot/lib/modes/rgbshift/index.js

A lightweight, cross-environment image library for applying unique effects via raw image buffers.

"use strict";
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
    return new (P || (P = Promise))(function (resolve, reject) {
        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
        step((generator = generator.apply(thisArg, _arguments || [])).next());
    });
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.rgbshift = void 0;
const rgbshift = (_a, ...args_1) => __awaiter(void 0, [_a, ...args_1], void 0, function* ({ data, width, height }, options = {}) {
    var _b, _c, _d;
    const redShift = (_b = options.redShift) !== null && _b !== void 0 ? _b : { x: 5, y: 0 };
    const greenShift = (_c = options.greenShift) !== null && _c !== void 0 ? _c : { x: -5, y: 0 };
    const blueShift = (_d = options.blueShift) !== null && _d !== void 0 ? _d : { x: 0, y: 5 };
    const tempData = new Uint8Array(data); // Copy to avoid overwriting during shifts
    for (let y = 0; y < height; y++) {
        for (let x = 0; x < width; x++) {
            const idx = (y * width + x) * 4;
            // Shift red
            const rx = (x + redShift.x + width) % width;
            const ry = (y + redShift.y + height) % height;
            data[idx] = tempData[(ry * width + rx) * 4];
            // Shift green
            const gx = (x + greenShift.x + width) % width;
            const gy = (y + greenShift.y + height) % height;
            data[idx + 1] = tempData[(gy * width + gx) * 4 + 1];
            // Shift blue
            const bx = (x + blueShift.x + width) % width;
            const by = (y + blueShift.y + height) % height;
            data[idx + 2] = tempData[(by * width + bx) * 4 + 2];
            // Alpha unchanged
        }
    }
    return data;
});
exports.rgbshift = rgbshift;