<div id="diagram"></div>
<script>
$("#diagram").kendoDiagram({
    shapes: [{
        id: "rect1",
        type: "rectangle",
        x: 50,
        y: 50,
        height: 100,
        width: 150
    }]
});

var diagram = $("#diagram").getKendoDiagram();
var shape = diagram.getShapeById("rect1");
var rect = diagram.shapes[0];

// Create rotation center point
var center = new kendo.dataviz.diagram.Point(125, 100);

// Rotate the rectangle 45 degrees clockwise
rect.rotate(45, center);
console.log("Rectangle rotated 45 degrees around center point");

// Rotate with negative angle (counter-clockwise)
rect.rotate(-30, center);
console.log("Rectangle rotated -30 degrees around center point");
</script>