Reputation: 49
I am writing a little program in Processing3 that enables me to change the background to a specific colour RGB code stored in arrays. Each vale for R, G and B is stored in a separate array.
Changing the mouse horizontal position changes the colour of the background.
However this solutions code is quite repetitive, and there is a lot of if/else statements. I want to use a for() loop to simplify the code and make it less repetitive. However, i am struggling to include the mouse position variable in the for() loop. Is there to simplify this code using a for() loop and somehow map the mouse position to access array items? This is the code I have right now:
int[] r = {255,249,240,233,227};
int[] g = {115,138,157,173,187};
int[] b = {0,18,63,94,120};
void setup() {
size(500, 500);
}
void draw() {
int x = mouseX;
if(x >= 0 && x <=100) {
background(r[0], g[0], b[0]);
}
else if (x >= 101 && x <= 200){
background(r[1], g[1], b[1]);
}
else if (x >= 201 && x <= 300){
background(r[2], g[2], b[2]);
}
else if (x >= 301 && x <= 400){
background(r[3], g[3], b[3]);
}
else {
background(r[4], g[4], b[4]);
}
}
I wish to simplify the code to something more like this:
int[] r = {255,249,240,233,227};
int[] g = {115,138,157,173,187};
int[] b = {0,18,63,94,120};
void setup() {
size(500, 500);
}
void draw() {
for(int i=0; i<r.length; i++) {
background(r[i],g[i],b[i]);
}
}
However, I don't know how to change this code in a way, that the background colour would change depending on mouse horizontal position, as it is shown in the first example.
Thank you for your reply and help!
Upvotes: 1
Views: 1212
Reputation: 25432
If your steps between your different values are 100, then you can just divide the input X value by 100. Integer division will take care of the rest.
The if statement is just to make sure it stays within the bounds of your array.
int mouseX = ...;
int i = mouseX / 100;
if(i < r.length && i < g.length && i < b.length)
{
background(r[i], g[i], b[i]);
}
Upvotes: 1