rem: SetAPen( amiga_window->RPort, pen ); SetDrMd( amiga_window->RPort, JAM1 );
add: SetABPenDrMd( amiga_window->RPort, pen, 0, JAM1 );
context: ui_rect(  /* dest */ int x, int y, int cx, int cy,  /* brush */ int colour){  LONG pen = amiga_obtain_pen( colour );    x += amiga_window->BorderLeft;  y += amiga_window->BorderTop;//  printf( "rect: %d,%d %dx%d, color %x, pen %x\n", x, y, cx, cy, colour, pen );    SetAPen( amiga_window->RPort, pen );  SetDrMd( amiga_window->RPort, JAM1 );  RectFill( amiga_window->RPort, x, y, x + cx - 1, y + cy - 1 );  amiga_release_pen( pen );}