## annas 2 years ago write opengl code (function call only) and find composite transformation matrix (the sequence of transformation matrices) in homogeneous form that would produce the same transformation for : scaling a given cube by factor (2,3,4) about given point p(3,1,0)

1. annas

rotation of given point p(3,1,0) about x axis of angle 90?

2. amistre64

pfft, i got no idea what this is even saying at the moment

3. annas

lol its ok actually we have to make a composite matrix to solve this i m like messed up right now with these question :|

4. amistre64

good luck with it ;)

5. annas

lol thanks :P

Okay well in OpenGl you use a 4x4 augmented matrix, where the first 3x3 matrix has to do with it's rotation, the column matrix 4 is where in the world it is, and the 4th row is the transitioning of the matrix. Since you want a homogeneous matrix you will set the 4th column to all 0's. The 4th row would be your (2,3,4) Now about a point you would set that yourself in the 3x3 I believe as x = 3, y = 1, and z = 0. $\left[\begin{matrix}3 & 0 & 0 & 0 \\ 0 & 1 & 0 & 0 \\ 0 & 0 & 0 & 0 \\ 2 & 3 & 4 &0\end{matrix}\right]$ should be your matrix.

7. annas

Np, hope that works.... I normally have GlRotate() and other goodies to do the work for me :P.

Most schools like to teach you how to do it 100%, but with IDEs and such you don't need half of the crap they teach you.

10. annas

we are using Visual studio for this ... well its the first programming course i hate lol :)

Visual Studio for OpenGL? or OpenGL for C++????

OpenGL is awesome, but hard. IT's also overkill for a lot of things, but just one of the only 3D Libraries out there....

13. annas

visual studio C++ with openGl libraries

I code in Java and we have now JavaFX which has an Open GL wrapper.... I don't need all the lighting and shaders and poo poo :P.

15. annas

lol ... i might need your help with my project too ... actually my favorite site of coding is networking & web development stuff