When drawing LINES or TRIANGLES, vertex are accumulated in same buffer as QUADS and new draw calls are registered but QUADS drawing uses an index buffer for optimization, so, when adding LINES/TRIANGLES vertices we need to make sure next draw calls for QUADS keep aligned with indices buffer.
To get that we just add some alignment vertex at the end of the LINES/TRIANGLES draw calls, to make them multiple of 4 vertex.
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