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View Full Version : Matrix multiplication code anyone?



Questions Burner
02-17-2002, 08:01 AM
I just happened to forgot it, could you post the code.
I store the matrix in an array:

GLfloat matrix[16];

Mr_Smith
02-17-2002, 08:47 AM
i guess from the 16 elements your using a 4 by 4 matrix, the code for that is avaliable along with a definition a bit like the one you put there http://www.opengl.org/discussion_boards/ubb/smile.gif from the Game tutorials at http://nehe.gamedev.net/

Questions Burner
02-17-2002, 11:02 PM
The method his using I already know, I want the algoritm, you know, using loops to multiply.

Thanks anyway.

satan
02-18-2002, 03:46 AM
perhaps it helps if you take a look here http://mathworld.wolfram.com/

Fernando
02-18-2002, 07:26 PM
Maybe it'll help you!

void MultiplyMatrix (GLfloat *n1, GLfloat *n2, GLfloat *result) {
register GLbyte l, c, a;
GLshort lc;

for (l=0; l<=3; l++) {
for (c=0; c<=3; c++) {
lc = l*c;
for (a=0; a<=3; a++)
result[(lc)+c] += n1[(lc)+a] * n2[c + (a*4)];
}
}
}