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cg-hci_novice
03-20-2003, 07:43 PM
Hello,

I am trying to use gluLookAt with perspective projection to "view" a 2d array of square polygons of different colors that I have drawn. The problem is I can only see a few of these. I believe that I need to adjust the first 3 args to gluLookAt but am not sure if I need to adjust the others as well. I currently have:

gluLookAt(0, 0, 350, 0, 0, 0, 0, 1, 0);

in my display function.

I read thru:
http://www.opengl.org/developers/gaqs/techinical/viewing.htm

but am still confused about this.

Any suggestions are appreciated.

Thanks.

tbfx
03-31-2003, 08:02 PM
Increasing viewangle will help,
heres some more complete camera code
that may help


float eyex, eyey, eyez; // eye
float near, far; // near and far clipping distance
float viewangle; // vertical view angle in degrees
float twist; // rotation angle about the view axis

int width, height; // input canvas width and height

// temp variables
float upx, upy, upz;
float aspect;
float rx, ry, rz;

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
aspect = (float)width/(float)height;
gluPerspective(viewangle, aspect, near, far);
rx = coix - eyex;
ry = coiy - eyey;
rz = coiz - eyez;
if (rx != 0.0 | | rz != 0.0) {
upx = 0.0; upy = 1.0; upz = 0.0;
}
else {
upx = 0.0; upy = 0.0; upz = -1.0;
}
gluLookAt(eyex, eyey, eyez, coix, coiy, coiz, upx, upy, upz);
glRotatef(twist, rx, ry, rz);