LibGdx PolygonSpriteBatch不绘制所有多边形

I am trying to render a simple 2D landscape profile using PolygonSpriteBatch in libGdx to draw filled polygons on screen. I am no sure why, but the code only appears to be rendering every other polygon resulting in a striped pattern on screen (see screen shot below - the background is red, the landscape is green).I am trying to render a simple 2D landscape pro