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copied!<p>The code you have is hard to work off (as an outsider), since we need to know how the class <code>Matrixf</code> works. I will outline a method anyway, which may point you in the right direction. The simplest way you could represent a matrix in C/C++ is simply a 2D array of floating points like so:</p> <pre><code>float matrix[3][3]; // 3x3 Matrix </code></pre> <p>Considering you already know the maths, I think all you need is some guidance in terms of coding what you need. To multiply elements of two of these matrices simply do this:</p> <pre><code>matrixC[0][1] = matrixA[0][0] * matrixB[0][0]; </code></pre> <p>This will store the result of multiplying the top-left element of <code>matrixA</code> and the top-left element of <code>matrixB</code> in the top-middle element of <code>matrixC</code>. Essentially the first square bracket represents the <em>row</em> and the second square bracket represents the <em>column</em> (however it is totally up to you which order you want the rows and columns to be, just so long as you stay consistent).</p> <p>Vectors can be represented similarly:</p> <pre><code>float vector[3]; // 3d vector </code></pre> <p>Of course, since we are using C++, there are nicer ways to do this. It seems you have some resources that describe a class-centric method to doing this. The nice thing about a class based method is you can abstract multiplication operations in a neat manner like this:</p> <pre><code>Matrix3x3f matrix( 1.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f ); Vector3f vector( 0.2f, 1.4f, -3.1f ); matrix.multVec( vector ); </code></pre> <p>...or something along these lines.</p> <p>(It is also worth mentioning that there are libraries out there that already do this sort of thing, and efficiently too.)</p>

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