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{...} name under which the graphic will be known


Define code for a MetaPost graphic. The graphic can be placed in the document with \uniqueMPgraphic. Every time any of the following variables changes, the graphic is recompiled:



  fill fullcircle scaled 20pt withcolor \mycolor;

red: \uniqueMPgraphic{name}

blue: \uniqueMPgraphic{name}

This illustrates the fact that graphic is reused if the dimensions don't change.

	fill unitsquare
		xyscaled (\overlaywidth, \overlayheight)
                % `uniformdeviate 1` produces a random number between 0 and 1
		withcolor (uniformdeviate 1, uniformdeviate 1, uniformdeviate 1);


\framed[background=beta]{rather wide}

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