Draws a quadratic Bezier curve from the current point to (x,y) using (x1,y1) as the control point using absolute coordinates. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
Please note - quadratic curves are not the same as cubic curves. They cannot be joined smoothly.
Background color
 
Stroke color
 
Fill color
 
Draws a quadratic Bezier curve from the current point to (x,y) using (x1,y1) as the control point using absolute coordinates. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
Parameters
x1floatx coordinate of the control point
y1floaty coordinate of the control point
xfloatx coordinate of the end point
yfloaty coordinate of the end point
function pathCurveToQuadraticBezierAbsolute($strokeColor, $fillColor, $backgroundColor)
{
    $draw = new \ImagickDraw();

    $draw->setStrokeOpacity(1);
    $draw->setStrokeColor($strokeColor);
    $draw->setFillColor($fillColor);

    $draw->setStrokeWidth(2);
    $draw->setFontSize(72);

    $draw->pathStart();
    $draw->pathMoveToAbsolute(50, 250);

    // This specifies a quadratic bezier curve with the current position as the start
    // point, the control point is the first two params, and the end point is the last two params.
    $draw->pathCurveToQuadraticBezierAbsolute(
        150, 50,
        250, 250
    );

    // This specifies a quadratic bezier curve with the current position as the start
    // point, the control point is mirrored from the previous curves control point
    // and the end point is defined by the x, y values.
    $draw->pathCurveToQuadraticBezierSmoothAbsolute(
        450, 250
    );

    // This specifies a quadratic bezier curve with the current position as the start
    // point, the control point is mirrored from the previous curves control point
    // and the end point is defined relative from the current position by the x, y values.
    $draw->pathCurveToQuadraticBezierSmoothRelative(
        200, -100
    );

    $draw->pathFinish();

    $imagick = new \Imagick();
    $imagick->newImage(700, 500, $backgroundColor);
    $imagick->setImageFormat("png");

    $imagick->drawImage($draw);

    header("Content-Type: image/png");
    echo $imagick->getImageBlob();

}