dear members,

I started to play with spotlights, and I am trying to understand them and the 3d space used by Processing. I can't see why the square turns black in the code below. What I can understand is that the spot is not moving, and the square has a fixed Z coordinate; so, the lighting shouldn't be being transformed, should it? I also tried to add a "translate (0,0,150)", to see if the transformations were added along multiple draw() calls, but nothing changed.

thanks for your time,
andrei



void setup() {  
 size(300, 300, P3D);
 colorMode(RGB,255);
 background(128);
}

float i = 1;
float aresta;

void draw() {  
 
 spotLight(255, 128, 0, 100, 100, -50, 0, 0, -1, PI/2, 2);

 aresta = 100*i;
 
 translate(0,0,-150);
 fill(255,255,255);    
 rect(0,0,aresta,aresta);
 
 i += .001;  
}

You'd need to use GLSL shaders to get per pixel spotlight effects unfortunately.

Also the lighting is additive, so you'd not be able to get coloured lights in a bright scene.. it'd have to be black outside the areas covered by the spotlight .