making camera move with mouse

Hi,

I was wondering how I can use the Windows API and OpenGL to control the Camera, so when I move the mouse the camera moves like in an FPS Game.

with OpenGL I can use the glutMotionFunc(mouse)

where 'mouse' is the function that controls the view port rite?

but with Windows API what Do I do?

thx.

You check for WM_MOUSEMOVE messages in your windowprocedure function.

ah,

k thx, i'll give it a shot.

so what will the variables be?

case WM_MOUSEMOVE:
{

}

Whatever you call them in game. read up on what WM_MOUSEMOVE sends as lParam and wParam. Then you need to setup a camera system in your game. After that you need to add code in there to move the camera depending on how you moved the mouse.

hmm

so the messages isn't mouseup mousedown

lParam and wParam represents the dimentsions of the viewing volume anyways rite?

so in the case WM_MOUSEMOVE

I have to have gluLookAt(whatever goes in here)

to control the camera rite? ok now I understand but how do I use wParam and lParam exactly.

the way I understand this is that I have to create some variables to control gluLookAt()

and then I have to use wParam and lParam to control those variables so that when the mouse moves the camera moves.

am I right?

I dont know which one but I believe either wParam or lParam contains the current mouseposition or something along those lines.

hmm it doesn't seem to work

here's my code.

case WM_MOUSEMOVE:
{
switch (wParam)
{
camY = (-wParam) + 250;
}
switch (lParam)
{
camX = lParam + 400;
}

gluLookAt(camX, camY, 5, 0, 0, 0, 0, 1, 0);
}

no, that is the wrong aproach, look at this page.

ah so its the lParam thats controling the mouse position.

and Whoa! MSDN is useful

I didn't think to look on it thx alot will look into it, I am kinda hopeless at programming but I am trying :D,

thx to people like you for helping :D

hmm I tried the GET_X_LPARAM and the GET_Y_LPARAM it said Identifier not found..

Try using this instead:

Code:

---

int x = LOWORD(lParam);
int y = HIWORD(lParam);

---

ok i got the camera and the mouse to work but i have another problem hehehehe

now the wasd button won't work with properly, the camera won't move in the direction it is headed, it pans in the x and z axis but won't 'head' in the direction the camera is facing

here is my code for the WASD

Code:

---

if (keys['W'])
                                        {
                                                camera_x -= (float)sin(direction * piover180) * 0.05f;
                                                camera_z -= (float)cos(direction * piover180) * 0.05f;
                                        }
                                        if (keys['S'])
                                        {
                                                camera_x += (float)sin(direction * piover180) * 0.05f;
                                                camera_z += (float)cos(direction * piover180) * 0.05f;
                                        }
                                        if (keys['A'])
                                        {
                                                camera_x += (float)cos(direction * piover180) * 0.05f;
                                                camera_z += (float)sin(direction * piover180) * 0.05f;
                                        }
                                        if (keys['D'])
                                        {
                                                camera_x -= (float)cos(direction * piover180) * 0.05f;
                                                camera_z -= (float)sin(direction * piover180) * 0.05f;
                                        }

---

where direction = mouse_y = LOWORD(lParam);

here isthe code for how the transformation is applied

Code:

---

GLfloat position_x = -camera_x;
        GLfloat position_z = -camera_z;
        GLfloat world_rotate = 360.0f + mouse_y;
                       
        glRotatef(mouse_x, 1.0f, 0.0f, 0.0f);
        glRotatef(world_rotate, 0.0f, 1.0f, 0.0f);
       
       

        glTranslatef(position_x, -height, position_z);

---

I think I have to do some trig maths to figure this out.

YAY I figured it out :D

I was just observing the behavior of those buttons and came to a conclusion that I just need to change the directions to -direction in the formula used to control the W and the S and the A and the D and they all work nicely now :D