code.js

function main() {
    if (figma.currentPage.selection.length !== 2) {
        figma.closePlugin("⚠️ Please select 2 layers.");
        return;
    }
    figma.showUI(__html__, { width: 360, height: 230 });
    let selection1 = figma.currentPage.selection[0];
    let selection2 = figma.currentPage.selection[1];
    figma.ui.postMessage([selection1.name, selection2.name]);
    figma.ui.onmessage = (msg) => {
        if (msg.type === "selection-order") {
            console.log(msg.order);
            let originLayer, targetLayer;
            if (msg.order) {
                originLayer = selection2;
                targetLayer = selection1;
            }
            else {
                originLayer = selection1;
                targetLayer = selection2;
            }
            if (targetLayer.type == "GROUP") {
                figma.closePlugin("⚠️ Group layer cannot be set as target.");
                return;
            }
            if (targetLayer.type == "SLICE") {
                figma.closePlugin("⚠️ Slice layer cannot be set as target.");
                return;
            }
            console.log(originLayer);
            originLayer
                .exportAsync({ constraint: { type: "SCALE", value: 2 }, format: "PNG" })
                .then((bytes) => {
                // console.log(bytes);
                const image = figma.createImage(bytes);
                let newPaint = [];
                newPaint = JSON.parse(JSON.stringify(targetLayer.fills));
                newPaint.push({
                    imageHash: image.hash,
                    scaleMode: "TILE",
                    scalingFactor: 0.5,
                    type: "IMAGE",
                });
                // console.log(newPaint);
                targetLayer.fills = newPaint;
            })
                .then(() => {
                figma.closePlugin();
            });
        }
    };
}
main();