Hello,

I used the picking with projection code from Tom Carden for creating buttons in 3D. Unfortunately, I discover now, after some changes, that for each button I create there is a "ghost-button".

I asked myself if it could be a wrong use of pushMatrix();/ popMatrix();, but I don't have enought experience with processing to find the fault myself..

I would be very grateful for some help.
Thank you very much,
David  



code:

import processing.opengl.*;
import javax.media.opengl.GL;


PVector camPosition;
PVector camLookAt;
float camHeight = -6;

Vector triangles_01 = new Vector();

float currentAngle = -1.5;
int picked_01;


class Vector3d {

 float x,y,z;

 Vector3d(float x, float y, float z) {
   this.x = x;
   this.y = y;
   this.z = z;
 }



 Vector3d project() {
   return new Vector3d(screenX(x,y,z),screenY(x,y,z),screenZ(x,y,z));
 }

}



////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////



class Triangle_01 implements Comparable {

 Vector3d a,b,c;
 Vector3d pa,pb,pc;
 boolean clicked = false;


 
 Triangle_01(Vector3d v1, Vector3d v2, Vector3d v3)
 {
   this.a = v1;
   this.b = v2;
   this.c = v3;
 }
 
 void project() {
   pa = a.project();
   pb = b.project();
   pc = c.project();
 }
   
 boolean mouseOver() {
   Polygon p = new Polygon( new int [] { (int)pa.x, (int)pb.x, (int)pc.x }, new int [] { (int)pa.y, (int)pb.y, (int)pc.y }, 3);
   return p.inside(mouseX,mouseY);
 }
 
 int compareTo(Object other) {
   // compare average depth
   float d1 = pa.z+pb.z+pc.z;
   Triangle_01 t2 = (Triangle_01)other;
   float d2 = t2.pa.z+t2.pb.z+t2.pc.z;
   if (d1>d2) {
     return 1;
   }
   else if (d1==d2) {
     return 0;
   }
   else {
     return -1;
   }
 }
 

}




////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////


int getPicked_01() {
 int picked_01 = -1;
 if (mouseX >= 0 && mouseX < width && mouseY >= 0 && mouseY < height) {
   for (int i = 0; i < triangles_01.size(); i++) {
     Triangle_01 t = (Triangle_01)triangles_01.get(i);
     t.project();
   }
   Collections.sort(triangles_01);
   for (int i = 0; i < triangles_01.size(); i++) {
     Triangle_01 t = (Triangle_01)triangles_01.get(i);
     if(t.mouseOver()) {
       picked_01 = i;
       break;
     }
   }
 }
 return picked_01;
}


////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////

void setup() {
 size(1000, 562,OPENGL);
 

 camPosition = new PVector( -26.0, camHeight, 12.71);
 camLookAt = new PVector(camPosition.x + 100*cos(currentAngle), camPosition.y, camPosition.z + 100*sin(currentAngle));


 {
   Vector3d v1 = new Vector3d(-25.5,-5.0,10.3); //unten
   Vector3d v2 = new Vector3d(-26.3,-5.75,12.05); //Seite rechts
   Vector3d v3 = new Vector3d(-26.0,-5.0,12.85); //Spitze
   Vector3d v4 = new Vector3d(-25.3,-4.2,12.2); //Seite links
 
  triangles_01.add(new Triangle_01(v1, v2, v3));
  triangles_01.add(new Triangle_01(v1, v3, v4));
 }


 noStroke();
 }









void draw() {
 background(255);


 beginCamera();
   camera(camPosition.x, camPosition.y, camPosition.z,
          camLookAt.x, camLookAt.y, camLookAt.z,
          0, 1, 0);
   
   //for perspective
   float aspect = float(width)/float(height);
   perspective(1.235, aspect, .1, 500);
 endCamera();





  pushMatrix();

 picked_01 = getPicked_01();
 


 {
 beginShape(TRIANGLES);
 noStroke();
 for (int i = 0; i < triangles_01.size(); i++) {
   Triangle_01 t = (Triangle_01)triangles_01.get(i);
   if (i == picked_01) {
     fill(#ff0000);
   }
   else {
     fill(#050505);
   }
 
   vertex(t.a.x,t.a.y,t.a.z);
   vertex(t.b.x,t.b.y,t.b.z);
   vertex(t.c.x,t.c.y,t.c.z);
   
    if (t.clicked) {
      link("
     
     
      //your link
     
     
      ");
      t.clicked = false;
      }
   
 }
 endShape();  
 }
 
 popMatrix();

}


void mouseReleased() {
 if (picked_01 >= 0 && picked_01 < triangles_01.size()) {
   Triangle_01 t = (Triangle_01)triangles_01.get(picked_01);
   t.clicked = !t.clicked;
 }
}

ben_hem wrote on Oct 16^th, 2009, 11:36pm:
Actually, it won't compile, so I suppose the link have been hidden (or OP couldn't let it because of spam policy of the forum).

Quote:
Not really, they are legal, and can even be useful to limit the scope of some local variables.. Although I see this rarely used (it is better to make small functions instead).

Quote:
Ah, where did you saw that Not in float() page at least.

Quote:
Well, fill(#ff0000); is legal in Processing, that's just fill with some color in hexa/Web form.

ben_hem wrote on Oct 17^th, 2009, 7:47am:

Sure not! I was terse, so I hope you wasn't offended by my tone. I just wanted to clarify some points, but your input is welcome.

I think it is autoformat which is buggy, I recall reports against it.
But I never use it...
And indeed, I saw these errors against float pseudo-functions but I had hard time to reproduce them when I wanted... And actually I rarely use this form too, to be honest.

I perceived the humor, but I preferred to clarify... Sometime, I fear my tone is wrongly translated. Even in my mother tongue: as you point out, in front of a person, an ironical remark can be tempered by expression, voice tone, a gesture... All things harder to express in writing.