Fast Way To Rotate In 2D

[Hmpf]

I have been researching this topic for a while and i have found out a fast way to rotate.

the usual way is to pass all the cor's to a simple

Xt=X*cos(angle)+Y*Sin(Angle)
Yt=Y*cos(angle)-X*sin(angle)

ofcourse its very slow, and even if you precalc the sin cos tables

a faster way is to rotate the edges and to complete it with Bresenham Line-Drawing Algorythm

And the easiest way i have found is :

lets say u want to rotate in 20 deg :

Xinc=Cos(20*pi/180) ,Yinc=sin(20*pi/180)

and for every line of the 2d pic u add the X and The Y

and when u finish the line , u add the x and y the SINCOS of the angle+90

to go forward


i got about 500 frames Non Compile version

even faster is not to draw the black points if your screen back is black

[MartinLiss]

Since this isn't a question, it should probably be in the CodeBank. Would you like me to move it?