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# how to do a Mouse drag in direct input

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Hi, I''m using the mouse direct input in the NeheGL basecode for my OpenGL project. This is what I am doing  switch (uMsg) // Evaluate Window Message { case WM_MOUSEMOVE: MouseX = (GLfloat)LOWORD(lParam); MouseY = (GLfloat)HIWORD(lParam); //isClicked = (LOWORD(wParam) & MK_LBUTTON) ? true : false; //isRClicked = (LOWORD(wParam) & MK_RBUTTON) ? true : false; break; case WM_LBUTTONUP: isClicked = false; DetectMouseClickUp(); break; case WM_RBUTTONUP: isRClicked = false; break; case WM_LBUTTONDOWN: isClicked = true; DetectMouseClick(); break; case WM_RBUTTONDOWN: isRClicked = true; break; case WM_ERASEBKGND: //Check to see if Windows is trying to erase the background return 0;  How do I detect a mouse drag or how do I get the X and Y while the mouse button is down... note: I am only using ORTHO

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While processing the WM_MOUSEMOVE, the wParam contains flags about which mouse buttons are pressed. So if you receive a WM_LBUTTONDOWN message before the WM_MOUSEMOVE message, you know that the user is dragging the mouse with the left button down. It looks like you have this commented out in your code.

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I understand what you mean... but could you be more elaborate I really am just starting out and used the codes i found in the forums...

thanks

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Hey actually i do the same thing but i only use the left button in my program but that doesnt matter. As soon as you move ur mouse it sends a WM_MOUSEMOVE call and in ur case it changes the MouseX and MouseY variables. If u want them to change only when u click on left mouse put a condition before and call a fonction that will change your image''s coordonate to drag ur image for example. U could do this:

switch (uMsg) // Evaluate Window Message
{
case WM_MOUSEMOVE:
if( isClicked ){
MouseX = (GLfloat)LOWORD(lParam);
MouseY = (GLfloat)HIWORD(lParam);
drag_my_image( MouseX, MouseY );//unless ur variables are global you dont have 2 do that: u put a condition in ur drag_my_image() fonction if( isClicked ) etc...
}
break;
case WM_LBUTTONUP:
isClicked = false;
DetectMouseClickUp();
break;
case WM_RBUTTONUP:
isRClicked = false;
break;
case WM_LBUTTONDOWN:
isClicked = true;
DetectMouseClick();
break;
case WM_RBUTTONDOWN:
isRClicked = true;
break;

case WM_ERASEBKGND: //Check to see if Windows is trying to erase the background
return 0;