src/vs/base/browser/ui/tree/abstractTree.ts/TreeRenderer/renderElement
class TreeRenderer:	renderElement(node: ITreeNode<T, TFilterData>, index: number, templateData: ITreeListTemplateData<TTemplateData>, height: number | undefined): void {
		if (typeof height === 'number') {
			this.renderedNodes.set(node, { templateData, height });
			this.renderedElements.set(node.element, node);
		}

		const indent = TreeRenderer.DefaultIndent + (node.depth - 1) * this.indent;
		templateData.twistie.style.paddingLeft = `${indent}px`;
		templateData.indent.style.width = `${indent + this.indent - 16}px`;

		this.renderTwistie(node, templateData);

		if (typeof height === 'number') {
			this.renderIndentGuides(node, templateData);
		}

		this.renderer.renderElement(node, index, templateData.templateData, height);
	}