if(x < 0 || y < 0) return 0;
PutPixel1LSB(ximage, x, y, pixel)    register XImage *ximage;    int x;    int y;    unsigned long pixel;{    if (pixel & 1)	ximage->data[ZINDEX1(x, y, ximage)] |= 1 << (x & 7);    else	ximage->data[ZINDEX1(x, y, ximage)] &= ~(1 << (x & 7));    return 1;}