Say I have a cube. Say the coordinate values are like this. (1 unit an arm)
GLfloat vertA[3] = { 0.5, 0.5, 0.5};
GLfloat vertB[3] = {-0.5, 0.5, 0.5};
GLfloat vertC[3] = {-0.5,-0.5, 0.5};
GLfloat vertD[3] = { 0.5,-0.5, 0.5};
GLfloat vertE[3] = { 0.5, 0.5,-0.5};
GLfloat vertF[3] = {-0.5, 0.5,-0.5};
GLfloat vertG[3] = {-0.5,-0.5,-0.5};
GLfloat vertH[3] = { 0.5,-0.5,-0.5};
If I translate it like
glTranslatef(1,2,3);
then 1,2 and 3 will be added to x,y and z coordinates respectively. and those are the new coordinate values of the translated cube. But if I rotate it some degree (with or without a translation)
glRotatef(25,0,0,1);
what is the coordinates of the rotated cube now? I am working new in opengl. I am using c++ on windows.
You should make yourself familiar with linear algebra and transformation matrices.
What glRotate will do is generating a rotation matrix and post-multiplying it to the current matrix. You should be aware of some things here: the glTranslate will not directly add anything to the vertex coordinates, and the glRotate will also not change the coordinates. All what these do is changing a single matrix. This matrix will accumulate the composition of all the transformations, and will be applied once to all the vertices during the draw call.
In your case, a rotation of 25 degrees around the z axis is desired, so the z coordinates will not be changed. The rotation matrix will look like this
| cos(25°) -sin(25°) 0 0 |
| sin(25°) cos(25°) 0 0 |
| 0 0 1 0 |
| 0 0 0 1 |
To apply this matrix to a vector (x,y,z,w)^T, we just multiply the matrix by the vector. Following the rules of that multiplcation, we get a new vector with
x' = cos(25°)*x -sin(25°)*y y' = sin(25°)*x +cos(25°)*y z' = z w' = w
This is just the rotation alone, not considering the translation. But you can put int the values of zour vertex and will get the transformed result back.