3d and 2d coordinates

djevazi

In 3d sketches null of coordinares begins here (green number "1"), how to make it begin there (green number "2"), like in 2d sketches? I realize that mouseX and mouseY not working properly because beginning of coordinates is not in the upper left corner.

jeremydouglass

@djevazi --

Can you explain your specific problem with an example sketch?

Here is a basic 3D sketch. When you draw a box simple, it appears by default in the upper left hand corner. When you draw a simple line (0,0) refers to the upper left hand corner.

void setup(){
  size(400, 400, P3D);
  noLoop();
}

void draw(){
  box(100,100,100);
  line(0,0,200,200);
}

These two examples don't exhibit your problem, so can you explain in more detail what you mean?

koogs

I think it's peasycam that centres the origin like that, it's not a default thing.

koogs

Alternatively, camera defines a lookat point, maybe he's doing that.

We won't know without some code being posted.

djevazi

https://forum.processing.org/two/discussion/comment/85129#Comment_85129 here is my previous post with a code, yes, the problem is that peasyCam draw null coordinates not in the upper left cornes, so, I can't understand how to make mouse coordinates work like in 2d.

jeremydouglass

@djevazi -- Two possible solutions:

1. Don't use PeasyCam -- just use P3D without it.
2. Change the origin while using PeasyCam -- I don't know what that would entail without actually seeing your code, but here is a previous discussion: https://forum.processing.org/one/topic/working-with-peasycam-change-the-origin-of-rotation.html

djevazi

@jeremydouglass, here is my code:

import peasy.*;
PeasyCam jcam;

float r=200;
int segments=30;
int brushsize = 200;
int cameraOn=2;

PVector thisPos;
float[] rotationspi;

ArrayList <Point> points = new ArrayList <Point>();

Brush brush;


void setup()
{
  size(800, 800, P3D);
  jcam = new PeasyCam(this, 600);

  for (int i=0; i<segments; i++)   // initialize
  {
    float lat = map(i, 0, segments, -HALF_PI, HALF_PI);
    for (int j=0; j<segments; j++)
    {
      float lon=map(j, 0, segments, -PI, PI);

      float x = r*sin(lon)*cos(lat);
      float y = r*sin(lon)*sin(lat);
      float z = r*cos(lon);
      PVector temp = new PVector(x, y, z);
      Point pt1= new Point(temp);
      points.add(pt1);
    }
  }

  PVector brushPos = new PVector(0, 0);
  brush = new Brush(brushPos);
}


void draw()
{
  background(150);

  rotationspi = jcam.getRotations();

  stroke(255,0,0);
  fill(255,0,0);

  pushMatrix();
  rotateX(rotationspi[0]);
  rotateY(rotationspi[1]);
  rotateZ(rotationspi[2]);
  line(0,250,0,0,0,0);
  text("local X", 260, 0, 0);
  line(0,0,0,250,0,0);
  text("local Y", 10, 250, 0);
  popMatrix();



  if(cameraOn%2==0)
  {
    jcam.setActive(true);
  }
  else
  {
    jcam.setActive(false);
  }


  for (int i=0; i<points.size(); i++)   // smooth selection
  {
    //float xx = screenX(points.get(i).pos.x, points.get(i).pos.y);
    //float yy = screenY(points.get(i).pos.x, points.get(i).pos.y);

    float force =  (dist(points.get(i).posScreen.x,points.get(i).posScreen.y, mouseX, mouseY)*255)/(brushsize/2);

    colorMode(RGB);

    if (dist(points.get(i).posScreen.x, points.get(i).posScreen.y, mouseX, mouseY)<brushsize/2)
    {
      points.get(i).colore = color(255, 0+force, 0+force);
    } else
    {
      points.get(i).colore = 255;
    }

    if(mousePressed)
    {
      if(dist(points.get(i).posScreen.x, points.get(i).posScreen.y,mouseX,mouseY)<brushsize/2)
      {
        PVector mouse = new PVector(mouseX-thisPos.x,mouseY-thisPos.y);
        mouse.setMag(100/force);
        points.get(i).pos.add(mouse);
      }
    }
    points.get(i).display();
  }

  //------

  jcam.beginHUD();   // 2D menu

  if(keyPressed)
  {
    if(key=='[')    
    {
      brushsize--;
    }
    if(key==']')
    {
      brushsize++;
    }
  }

  if(cameraOn%2==0)
  {
    fill(255);
    text("camera is ON",20,20);
  }
  else
  {
    fill(255);
    text("camera is OFF",20,20);
  }

  brush.pos= new PVector(mouseX, mouseY);  // brush
  brush.display();

  jcam.endHUD();
}

void mousePressed()
{
  thisPos = new PVector(mouseX,mouseY);
}

void keyPressed()
{ 
  if(key=='c')
  {
    cameraOn++;
  }

}


class Brush
{
  PVector pos;
  color brColor = color(255, 0, 0);

  Brush(PVector posIn)
  {
    pos = posIn;
  }

  void display()
  {
    noFill();
    stroke(255, 0, 0);
    pushMatrix();
    ellipse(pos.x, pos.y, brushsize, brushsize);
    ellipse(pos.x, pos.y, brushsize/2, brushsize/2);
    ellipse(pos.x, pos.y, 2, 2);
    popMatrix();
  }
}


class Point
{
  PVector pos;
  PVector posScreen=new PVector();  // we store the 2D pos 
  color colore;




  Point(PVector posIn)
  {
    pos = posIn;
  }

  void display()
  {
    noStroke();
    fill(colore);
    pushMatrix();
    translate(pos.x, pos.y, pos.z);
    box(3);

    posScreen.x = screenX( 0, 0, 0 );
    posScreen.y = screenY( 0, 0, 0 );

    popMatrix();
  }
}

jeremydouglass

@djevazi --

If you do decide to take the "don't use PeasyCam" route, a recent discussion that demonstrates implementing partial rotation of an object without it:

https://forum.processing.org/two/discussion/20235/align-box-with-vector

djevazi

thanks for help!