unsigned top, bottom, left, right, i;
bool empt;
#define MK_DTTMP(x,y) dttmp = dt + ((x + y * w) * 3)
#define NOEMPTY_PIX(empt) if (dttmp[0] != mr || dttmp[1] != mg || dttmp[2] != mb) {empt = FALSE; break;}
unsigned top, bottom, left, right, i;
bool empt;
#define MK_DTTMP(x,y) dttmp = dt + ((x + y * w) * 3)
#define NOEMPTY_PIX(empt) if (dttmp[0] != mr || dttmp[1] != mg || dttmp[2] != mb) {empt = FALSE; break;}