Hello,

I wrote a fonction that sould create a sort of diamond shape composed of 4 quarters of circles, I drew it in photoshop first to be sure of the positions of anchor and control points here is how it should look:

http://kazah.free.fr/processing/forme_lise.jpg

but in processing it looks like that:

http://kazah.free.fr/processing/forme_processing.png

It is a problem because we will use it as a pattern and it should create circles when applied to a grid, now it makes rouded corners squares...

any idea?

here is my code

int Ax and int Ay are the coordinates of the first anchor point, the top point of the shape, int taille is the variable that will determine the size of the shape
================================

void setup() {
 size(600, 600);
 noLoop();
 smooth();
noFill();
strokeWeight(1);
}

void draw() {
lise(width/2,(height/4),60);
}



void lise (int Ax, int Ay, int taille) {


beginShape();
 vertex(Ax, Ay);
 bezierVertex(Ax, Ay-taille, Ax, Ay-taille, Ax+taille, Ay-taille);
 bezierVertex( Ax, Ay-taille, Ax, Ay-taille,Ax, Ay-(taille)*2);
 bezierVertex(Ax, Ay-taille, Ax, Ay-taille, Ax-taille, Ay-taille);
 bezierVertex(Ax, Ay-taille, Ax, Ay-taille, Ax, Ay );
 endShape();

endShape();
}

=======================================================

thanks, it IS close!!!

as to drawing the circles, the thing is first the diamonds are in a grid and we see the circles at first but after they move aound when the grid is disrupted by a video capture. I am helping one of my students actually for her diploma project, and all her graphic design work uses this shape and now we work on a video installation, where the shapes size and movements will de determined by a dancer performing in front of the screen... actually we have the other parts kindof settled but we can't draw the shape right which I thought was the easy part...

Works!!!!!!!!

Here is how to draw a vary close ("one part in one thousand error would be one pixel on a screen circle of 14 inches at 73 DPI. It would be just over one pixel per inch on a 1200 DPI printer. ") approximation of a circle with bezier curves:

http://www.whizkidtech.redprince.net/bezier/circle/

now my shape looks good:

http://kazah.free.fr/processing/lise_good.png


here is the code

void setup() {
 size(600, 600);
 noLoop();
 smooth();
 noFill();
 strokeWeight(1);
}

void draw() {

 
 diamond(300,300,50);
}

void diamond (int ox, int oy, int rayon) {
 //kappa chiffre permettant de simuler des cercles avec des courbes de bezier
 //explication kappa:http://www.whizkidtech.redprince.net/bezier/circle/
 float kappa;
 kappa=(4.0 * (sqrt(2.0) - 1.0) / 3.0);
 //segment=longeur des segments reiant point d'ancrage a point de contrtole
 float segment;
 segment=rayon*kappa;
 //
  bezier(ox, oy, ox, oy-segment, (ox-rayon)+segment, oy-rayon, ox-rayon, oy-rayon);
 //
 bezier(ox-rayon, oy-rayon,(ox-rayon)+segment, oy-rayon,ox,oy-(rayon*2)+segment,ox,oy-(rayon*2));
//
 bezier(ox,oy-(rayon*2),ox,oy-(rayon*2)+segment,(ox+rayon)-segment,oy-rayon, ox+rayon,oy-rayon);
 //  
 bezier(ox+rayon,oy-rayon,(ox+rayon)-segment,oy-rayon,ox, oy-segment,ox,oy);
}