See the image. The triangle is a ConvexShape, the top side of the rectangle which can be seen is a RectangleShape, included for reference (in fact, the rectangle's x coordinates were set to be the same as those of the lower side of the triangle). There was a noticeable difference in size when the vertex coordinates were specified in clockwise order versus counter-clockwise order. All coordinates were integers.
For completeness - these were transparent shapes and what can be seen are the outlines.
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