RE: A83: Rotating sprites?

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RE: A83: Rotating sprites?

Jonathan,

You need to learn a little about linear (matrix) algebra.  If you store the sprite as a matrix, you can you can enlarge, shrink, flip, or distort it by performing row operations on the matrix.  It took me a whole quarter to get the hang of it, so I don't have a simple answer for you.  If you simply want to rotate it 90° CCW, multiply the sprite by the following matrix:

0  -1
1  0

If I were doing ASM I would send you some code.  In normal calculator mode, you can do these manipulations without knowing how to do row operations.

Mike


-----Original Message-----
From:	Jonathan Wang [SMTP:jwang@isb.bj.edu.cn]
Sent:	Friday, December 19, 1997 6:11 AM
To:	assembly-83@lists.ticalc.org
Subject:	A83: Rotating sprites?


Any ideas for rotating a sprite around its axis?

Jonathan Wang
jwang@isb.bj.edu.cn
jonathan_wang@hotmail.com

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