# Crappy mouse behaviour

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r2d2rigo    163
Hello, I have been lurking in this forum for a very long time, but now it comes the time to register and post some questions :) So, I'm trying to do some kind of engine, mainly for FPS-type games. The problem comes when I want to translate the mouse moving into view rotation. I'm using standard OpenGL + Win32 API, and to check for mouse input I have the following code scheme in the WM_MOUSEMOVE message: GetCursorPos(); CalcPositionAwayFromCenter(); AddAngles(); And, after the render takes place, I SetCursor() the position to the center of the screen (to prevent endless loops if I do it in the WM_MOUSEMOVE piece). The problem is, if the polycount of the scene is ~3k polys, the mouse moves ok. But if I navigate and get to places with ~20-30k (the frame rate is the same, only the render takes some milliseconds more to complete), the mouse is completely lagged. Does anyone have a clue on why does this happen?

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Palidine    1315
Why not just reset the cursor position immediately after you read it? That's the more realistic datapoint anyway.

-me

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r2d2rigo    163
Doing a call to SetCursorPos() generates a WM_MOUSEMOVE message. So, doing it inside the WM_MOUSEMOVE parsing function creates an endless loop... :P

EDIT: I'm going to try moving the mouse updating code to another place, so it looks like this:

Render();
ResetPosition();

I'll tell you if this does work.

EDIT2: Okay, it works flawless now :) The solution was to do the following:

ResetPosition();
Render();

Just as you said, Palidine. Thanks for the help :)

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Palidine    1315
But AFAIK you don't want to do it inside the message event queue. At least I never did anything like that when doing engine work. I've always just set up my app like this:

void updateInput(){    //to use your code    GetCursorPos();    CalcPositionAwayFromCenter();    AddAngles();    SetCursorPos( centerOfScreen );}void update(){    updateInput();    updateotherstuff();}int main(){    //replace this with the PeekMessage gameloop deal (i forget the code)    while (running)    {       update();    }}

and just drop the MOUSEMOVE message on the floor.

-me

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r2d2rigo    163
Yes, I did it just as you posted now. Look at the second edit of my previous post. Again, thanks for giving that idea. I can't believe I didn't think in anything that obvious :)