ref: 490c3d87cb558a8cfe8ad4db9f39c9cb3df91d17 dir: /sys/src/cmd/plot/libplot/erase.c/
#include "mplot.h" void erase(void){ m_swapbuf(); m_clrwin(clipminx, clipminy, clipmaxx, clipmaxy, e1->backgr); }