A bit more of this
I thought of a “simple” way to add colors to those pixy.land
animations, without having to write mathematical expressions that would generate 4D vectors, namely [r,R,G,B]
, where r
would be the radius of the disk, and [R,G,B]
its color, defined at each point.
On the contrary, we want to be able to keep mathematical expressions simple, and be amazed to see that it generates complicated animations
Also, the constraint I imposed on myself was to get the same animations as on tixy.land
, with the same previous formulas.
So I simply considered that mathematical expressions should return complex numbers C
rather than real numbers, with the following rules:
- the module
cabs(C)
of the complex numberC
determines the radius of the disk at each point(x,y)
. - The argument
carg(C)
of the complex numberC
determines its color, in the form of a hue (the argument can be seen as an angle, so the HSV space is particularly adapted here).
I’ve also added a new variable z
, shortcut for z = x + j*y
, where j
is the imaginary number [0,1]
(i
was already used in tixy.land
expressions).
What is cool is that the original colored scheme is preserved : if the expression returns a real number (i.e. a complex C = [ r,0 ]
), then cabs(C)
= abs(r)
is indeed the radius of the disk, and carg(C) = r>=0?0:pi
so two different colors are still mapped regarding to the sign of r
.
So, we get an equivalence with the previous (real-valued) formulas. This is nice.
Now, let me show you some simple examples below. As you see, the formulas remain simple, and we got full color rendering. Yipeee!!
with the time variable t
introduced:
And another one:
Nice, isn’t it ?