startshape SPIKES

rule SPIKES {
	4* {r 90} SPIKE {}
}

rule SPIKE {
	LSPIKE {}
}
rule SPIKE {
	LSPIKE { flip 90 }
}

rule LSPIKE {
	SQUARE {}
	LSPIKE { y 0.98 s 0.99 r 1}
}
rule LSPIKE 0.01 {
	SPIKE { r 90 }
	SPIKE { r -90 }
	LSPIKE { y 0.98 s 0.99  r 1}
}
