$WW,1$"Input Ptr" is the mouse.  In the future, might be joystick or pad.

$LK,"ip.pos.x",A="MN:ip"$ and $LK,"ip.pos.y",A="MN:ip"$ can be used to access the x and y coordinates of the input ptr.  They are relative to the screen, not window.  These can be used if you don't want to use msg passing.  $LK,"ip.pos.z",A="MN:ip"$ is the wheel.

$LK,"ip.pos_text.x",A="MN:CIPStateGlbls"$ and $LK,"ip.pos_text.y",A="MN:CIPStateGlbls"$ are the text column and row of the input ptr.  See $LK,"::/Demo/Games/Maze.CPP"$.

See $LK,"CIPStateGlbls",A="MN:CIPStateGlbls"$ and $LK,"CMouseStateGlbls",A="MN:CMouseStateGlbls"$.

$HL,1$//****
mouse.pos.x=mouse.prescale.x*mouse.scale.x*ip_grid.x_speed;
ip.presnap.x=ToI64(ip.scale.x*mouse.pos.x)+ip.offset.x;
if (ip_grid.snap)
  ip.pos.x=Trunc(ip.presnap.x/ip_grid.x)*ip_grid.x+ip_grid.x_offset;
else
  ip.pos.x=ip.presnap.x;
//****$HL,0$