just increase j slowly?

1. float j=-0.2;
2. void draw() {
3.   float s=map(j, -0.2, 0.1, -10, 10);
4.   println(s);
5.   if (j<0.1)
6.     j+=0.01;
7.   else
8.   {
9.     println("End.");
10.     noLoop();
11.   }
12. }

hmm maybe i don't get something
or i just didn't explain myself properly...

i need s to follow j
so now if  for example j = -0.2 ,s =-10
if j jumps to 0.1, s =10,
so far so good

but i need  to make s to "slide" from -10 to 10, like -10,-9, -8...till 10
not just jump straight from -10 to 10 as it does now

so every time j randomly jumps from point a to b
s slides from point a to b

does it make sense?

void draw(){
float j=random(-0.2, 0.1);
float s=map(j,-0.2,0.1,-10,10);
println(s);
}

thank you
i try to understand (processing noob here)
how to control slide between values speed?

can you do the same with lerp?

lerp and map might be similar

in both cases you have a range.

• lerp gives you a value (that you don't have before) within one range, depending on amt between 0 and 1.http://www.processing.org/reference/lerp_.html
  

• map needs a value (that you must have before) and changes it from one range to another (with same percentage for both ranges).

I assume lerp is similar to map because you can say:

• x = map (amt, 0, 1, x1, x2);
• x = lerp (x1,x2,amt);

But you can also use a loop (draw in itself is a loop) and say

• i++;
• or
• i+=0.1;
• i+=2;
• i+=.02;

etc. and thus control the speed of the transition.

Greetings, Chrisir