title: Capture Mouse Position
body: <p>This is a Win32 program, and I Write a CaptureMousePosition function to capture the mouse's position.<img src="https://i.stack.imgur.com/YGWNe.jpg" alt="This is CaptureMousePosition function."></p>
  
  <p>and I call the function in WM_MOUSEMOVE message.<img src="https://i.stack.imgur.com/qqLWs.jpg" alt="This is where I call the function."></p>
  
  <p>Then I run the program.when my mouse moves on the red point, it is (126,112).There is no problem here.<img src="https://i.stack.imgur.com/IJRIU.jpg" alt="run the program."></p>
  
  <p>But when my mouse moves on the blue point,it becomes (960,940).How can it happen,I don't understand, why the red point is (126,112),but the blue point is (960,940).the blue point should be ( &lt; 126, &lt; 112).how to fix it.<img src="https://i.stack.imgur.com/GVwQD.jpg" alt="enter image description here"></p>