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twa625
06-01-2012, 11:27 AM
Hi,

Recently I started learning OpenGL and I have got myself both the superbible (the blue book) and the programming guide(the red book). The part where they describe the order for modeling transformation confuses me. In the red book, "viewing->viewing and modeling transformation->thinking about transformations", rotation and then translation has, strangely, the same result as translation and then rotation described in the blue book, "geometric transformations: pipeline->understanding transformations->modeling transformations".

Why is there discrepancy in these two books? Could anyone help explain a little? Do I miss something here?

All the best!

thokra
06-01-2012, 11:49 AM
Show us the math please. Not everyone has access to all books, you know?

Aleksandar
06-01-2012, 04:28 PM
My personal opinion is that the Red book gave a better explanation. I've just take a look at the Superbible 4th edition, and find that it isn't explained quite correctly. In fact, Superbable assumes transformations of local coordinate system. The figure 4.3 is right if transformation is related to the local coordinate system. The Red book has a great explanation about two way of thinking about transformations.

twa625
06-02-2012, 06:37 AM
Thanks for your replies.

Thokra, there isn't any maths deduction involved, only text descriptions so I could only describe it with texts as well.

Aleksandar, I agree with you that the red book gives a more thorough explanation. I will ignore the difference and go with the red book version then.