obsidian-excalidraw-plugin/ea-scripts/Normalize Selected Arrows.md

/*

Download this file and save to your Obsidian Vault including the first line, or open it in "Raw" and copy the entire contents to Obsidian.

This script will reset the start and end positions of the selected arrows. The arrow will point to the center of the connected box and will have a gap of 8px from the box.

Tips: If you are drawing a flowchart, you can use Normalize Selected Arrows script to correct the position of the start and end points of the arrows, then use Elbow connectors script, and you will get the perfect connecting line!

See documentation for more details: https://zsviczian.github.io/obsidian-excalidraw-plugin/ExcalidrawScriptsEngine.html

*/
const selectedIndividualArrows = ea.getMaximumGroups(ea.getViewSelectedElements())
	.reduce((result, group) => (group.length === 1 && (group[0].type === 'arrow' || group[0].type === 'line')) ? 
			[...result, group[0]] : result, []);

const allElements = ea.getViewElements();
for(const arrow of selectedIndividualArrows) {
	const startBindingEl = allElements.filter(el => el.id === (arrow.startBinding||{}).elementId)[0];
	const endBindingEl = allElements.filter(el => el.id === (arrow.endBinding||{}).elementId)[0];

	if(startBindingEl) {
		recalculateStartPointOfLine(arrow, startBindingEl, endBindingEl);
	}
	if(endBindingEl) {
		recalculateEndPointOfLine(arrow, endBindingEl, startBindingEl);
	}
}

ea.copyViewElementsToEAforEditing(selectedIndividualArrows);
ea.addElementsToView();

function recalculateStartPointOfLine(line, el, elB) {
	const aX = el.x + el.width/2;
    const bX = (line.points.length <=2 && elB) ? elB.x + elB.width/2 : line.x + line.points[1][0];
    const aY = el.y + el.height/2;
    const bY = (line.points.length <=2 && elB) ? elB.y + elB.height/2 : line.y + line.points[1][1];

	line.startBinding.gap = 8;
	line.startBinding.focus = 0;
	const intersectA = ea.intersectElementWithLine(
            	el,
				[bX, bY],
            	[aX, aY],
            	line.startBinding.gap
          	);

    if(intersectA.length > 0) {
		line.points[0] = [0, 0];
		for(var i = 1; i<line.points.length; i++) {
			line.points[i][0] -= intersectA[0][0] - line.x;
			line.points[i][1] -= intersectA[0][1] - line.y;
		}
		line.x = intersectA[0][0];
		line.y = intersectA[0][1];
	}
}

function recalculateEndPointOfLine(line, el, elB) {
	const aX = el.x + el.width/2;
    const bX = (line.points.length <=2 && elB) ? elB.x + elB.width/2 : line.x + line.points[line.points.length-2][0];
    const aY = el.y + el.height/2;
    const bY = (line.points.length <=2 && elB) ? elB.y + elB.height/2 : line.y + line.points[line.points.length-2][1];

	line.endBinding.gap = 8;
	line.endBinding.focus = 0;
	const intersectA = ea.intersectElementWithLine(
            	el,
				[bX, bY],
            	[aX, aY],
            	line.endBinding.gap
          	);

    if(intersectA.length > 0) {
    	line.points[line.points.length - 1] = [intersectA[0][0] - line.x, intersectA[0][1] - line.y];
	}
}