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@onesy/utils

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"use strict"; var __importDefault = (this && this.__importDefault) || function (mod) { return (mod && mod.__esModule) ? mod : { "default": mod }; }; Object.defineProperty(exports, "__esModule", { value: true }); const clamp_1 = __importDefault(require("./clamp")); const canvasFilterFade = (value_, canvas) => { const context = canvas.getContext('2d'); const imageData = context.getImageData(0, 0, canvas.width, canvas.height); const { data } = imageData; let value = value_; if (value > 0) value *= -1; const factor = (259 * (value + 255)) / (255 * (259 - value)); for (let i = 0; i < data.length; i += 4) { data[i + 0] = (0, clamp_1.default)((factor * (data[i + 0] - 100)) + 100, 0, 255); data[i + 1] = (0, clamp_1.default)((factor * (data[i + 1] - 100)) + 100, 0, 255); data[i + 2] = (0, clamp_1.default)((factor * (data[i + 2] - 100)) + 100, 0, 255); } context.putImageData(imageData, 0, 0); return canvas; }; exports.default = canvasFilterFade;