Why are these shapes the wrong color? - colors

Question

So I'm writing up a processing sketch to test a randomized terrain generator for a scorched earth clone I'm working on. It seems to work as intended but with one minor problem. In the code I generate 800 1 pixel wide rectangles and set the fill to brown beforehand. The combination of the rectangles should be a solid mass with a brown dirt-like color (77,0,0).
However, the combination shows up as black regardless of the rgb fill value set. I think it might have something to do with each rectangle's border being black? Does anyone know what is happening here offhand?
final int w = 800;
final int h = 480;
void setup() {
size(w, h);
fill(0,128,255);
rect(0,0,w,h);
int t[] = terrain(w,h);
fill(77,0,0);
for(int i=0; i < w; i++){
rect(i, h, 1, -1*t[i]);
}
}
void draw() {
}
int[] terrain(int w, int h){
width = w;
height = h;
//min and max bracket the freq's of the sin/cos series
//The higher the max the hillier the environment
int min = 1, max = 6;
//allocating horizon for screen width
int[] horizon = new int[width];
double[] skyline = new double[width];
//ratio of amplitude of screen height to landscape variation
double r = (int) 2.0/5.0;
//number of terms to be used in sine/cosine series
int n = 4;
int[] f = new int[n*2];
//calculating omegas for sine series
for(int i = 0; i < n*2 ; i ++){
f[i] = (int) random(max - min + 1) + min;
}
//amp is the amplitude of the series
int amp = (int) (r*height);
for(int i = 0 ; i < width; i ++){
skyline[i] = 0;
for(int j = 0; j < n; j++){
skyline[i] += ( sin( (f[j]*PI*i/height) ) + cos(f[j+n]*PI*i/height) );
}
skyline[i] *= amp/(n*2);
skyline[i] += (height/2);
skyline[i] = (int)skyline[i];
horizon[i] = (int)skyline[i];
}
return horizon;
}

Answer 1

I think it might have something to do with each rectangle's border being black?
I believe this is the case. In your setup() function, I added the noStroke() function before you draw the rectangles. This removes the black outline to the rectangles. Since each rectangle is only 1 pixel wide, having this black stroke (which is on by default) makes the color of each rectangle black, no matter what color you try to choose before.
Here is an updated setup() function - I now see a reddish brown terrain:
void setup() {
size(w, h);
fill(0, 128, 255);
rect(0, 0, w, h);
int t[] = terrain(w, h);
fill(77, 0, 0);
noStroke(); // here
for (int i=0; i < w; i++) {
rect(i, h, 1, -1*t[i]);
}
}