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Ehsan Nekooee
09-04-2009, 01:25 PM
Hi people

How can I rotate a camera to look around the scene?

I checked some complicated tutorials which they made me so much confused.

I would be appreciated if you could show me the way as simple as possible.

Thanx

P.S: I use Microsoft Visual c++ 2008

Ehsan Nekooee
09-05-2009, 09:36 AM
well, Still your comments are welcome guys .....

vivek vyas
09-05-2009, 12:11 PM
some times talking
i don't understand P.S.
if you are looking for camera which like ghost(go through wall)
then:
1. download mesa3D demos library
2. Clear that you have following libraries
a.related to OpenGL(link library with dll/so)
b.related to glut32(link library with dll/so)
c.related toglu32(link library with dll/so)
3. any of the demos containing gluLookAt function
understand the ObjPos function
4. make your own source with following precaution

i) don't use glLoadIdentity(); and glMatrixMode(GL_PROJECTION); in your draw function(it might used for 2Dness I stuck with that for 2 months and no one correctly regard to that and need to understand by my self
i read mesa codes 50 times to get it)
ii) your resize function must contains glLoadidentity(); after first glMatrixMode();
iii)LookAt must under
PushMatrix();
*/Lookat*/
PushMatrix();
PopMatrix();
PopMatrix();

At Last the body of code should be


// at just looking it you may not understand but after done it
// u find setting camera is of just few punch code...
//include the neccessary things gl,glu,glut

draw()
{
Clear
ClearColor
PushMatrix
camramath
LookAt(with cameramath variables);
PushMatrix
draw the things
PopMatrix
PopMatrix
}
resize(int ,int)
{
//...read_mesa_code//
}
key+Skey()
{
//....read_mesa_code for Angles/moves
}
main()
{
//u know that

DisplayFunc(draw);
ReshapeFunc(resize);
KeyboardFunc(key);
MainLoop();
}
//I hope you read any of Mesa's demos Code so undrstand the text

watch at
The Industry's Foundation for High Performance Graphics
watch at a text box above the
Graphics(specially above phics)
it used for search word "word in box"
lis in whole opengl.org site
so you find the thread:- "camera"

Ehsan Nekooee
09-05-2009, 12:32 PM
Thanx vivek vyas

I also look for some explanations on math related things...

any comments would be appreciated

vivek vyas
09-05-2009, 12:36 PM
have you installed demos at first
anyway it is trignometric maths just three lines needed but works much i had programmed some my self demos with png images

Ehsan Nekooee
09-05-2009, 01:06 PM
Well ...
I Can work with OpenGL functions a little. I just don't know about the maths basics like Camera transformations.

The exact thing I want to know is like First Person Shooter games. When I push the left arrow kew, the camera rotates to left around Y Axis and when I push the right arrow key, vise versa.

vivek vyas
09-05-2009, 02:10 PM
no read demos Mesa lies on sf.net
and in progs/demos/tunnel.c
found calcobjpos
then see at what places it use and then mimic it.
if compile tunnel.c
u find it is look like FPS(my mean someone goes through tunnel)