Hi everyone,

I just made this tiny library that makes it easy to do corner pin keystoning from within Processing.  Calibration is done by dragging and dropping surface corners until they look straight or map onto a surface you'd like to project on (flat surfaces only at the moment!). Used in conjunction with Andres Colubri's excellent GLGraphics, performance is pretty decent even with multiple surfaces.  

Finally, a neat little feature is that the library will also calculate the undistorted mouse position from inside a distorted surface. This is useful if you want to control things in the sketch from a laptop while projecting.

Hopefully this will be helpful to those of you working with video projectors! Feedback, suggestions or feature requests are welcome.

http://keystonep5.sourceforge.net

d.

Hello,

I'm very glad you're working on this library, great stuff!
It really simplifies my work...

I actually try this library in a new project
and I have a question about the load / save functions
When I save a configuration, the xml uses float values
then when I use the load function, it crashes the application with this message "NumberFormatException: For input string:"0,000000"
Is it waiting for an integer value?

Thx

P.

Yes, that's it:
Keystone.java
fmt = "<point i=\"%d\" x=\"%f\" y=\"%f\" u=\"%f\" v=\"%f\"></point>";
fmted = String.format(fmt, i, s.mesh[i].x, s.mesh[i].y, s.mesh[i].u, s.mesh[i].v);
xml.addChild(new XMLElement(fmted));
String.format is locale sensitive.
And loading is done (in CornerPinSurface.java) with xml.getFloatAttribute()

You can try and do:
Locale locale = new Locale("EN");
Locale.setDefault(locale);
before doing the save.

Hello

Another problem with this library...

I want to save configurations for 8 surfaces, associated with 8 GL textures, and then load this configurations when opening again the sketch
It seems that this operation doesn't keep the good order
It looks like surface [1] is no more associated with texture [1], but with another one.

Is there a way to resolve this problem?

P.

Hello

New version is ok, it's working fine for me
Thx very much
This is a very usefull tool for the kind of stuff I do
I think the library will be very used with the developpement of GLgraphics / GLmovie, which makes processing one of the best solution for real time video

P.

First of, thanks for the library.

I have a question, it more has to do with drawing offscreen than keystone.

For some reason the center point of the 3D object is shifted once i draw everything into offscreen, can't figure out why. here is example where I added Keystone to Esfera:

Code:

import processing.opengl.*;
import codeanticode.glgraphics.*;
import deadpixel.keystone.*;

GLGraphicsOffScreen offscreen;

Keystone ks;
CornerPinSurface surface;

int cuantos = 8000;
pelo[] lista ;
float[] z = new float[cuantos]; 
float[] phi = new float[cuantos]; 
float[] largos = new float[cuantos]; 
float radio = 200;
float rx = 0;
float ry =0;

void setup() {
  size(1024, 768, GLConstants.GLGRAPHICS);
  radio = height/3.5;
  
  lista = new pelo[cuantos];
  for (int i=0; i<cuantos; i++){
    lista[i] = new pelo();
  }
  noiseDetail(3);
//--------------------------
  offscreen = new GLGraphicsOffScreen(this, width, height);

  ks = new Keystone(this);
  surface = ks.createCornerPinSurface(width, height, 1);
}

void draw() {
  PVector mouse = surface.getTransformedMouse();
  offscreen.beginDraw();
  offscreen.background(0);
  offscreen.translate(width/2,height/2,height);
  float rxp = ((mouse.x-(width/2))*0.005);
  float ryp = ((mouse.y-(height/2))*0.005);
  rx = (rx*0.9)+(rxp*0.1);
  ry = (ry*0.9)+(ryp*0.1);
  offscreen.rotateY(-rx);
  offscreen.rotateX(ry);
  offscreen.fill(0);
  offscreen.noStroke();

  offscreen.sphere(radio);

  for (int i=0;i<cuantos;i++){
    lista[i].dibujar();
  }
  printCamera();

  offscreen.endDraw();
  background(0);

  surface.render(offscreen.getTexture());

}

void keyPressed() {

  switch(key) {
  case 'c':
    // enter/leave calibration mode, where surfaces can be warped 
    // & moved
    ks.toggleCalibration();
    break;

  case 'l':
    // loads the saved layout
    ks.load();
    break;

  case 's':
    // saves the layout
    ks.save();
    break;
  }
}

class pelo
{
  float z = random(-radio,radio);
  float phi = random(TWO_PI);
  float largo = random(1.15,1.2);
  float theta = asin(z/radio);

    void dibujar(){

    float off = (noise(millis() * 0.0005,sin(phi))-0.5) * 0.3;
    float offb = (noise(millis() * 0.0007,sin(z) * 0.01)-0.5) * 0.3;

    float thetaff = theta+off;
    float phff = phi+offb;
    float x = radio * cos(theta) * cos(phi);
    float y = radio * cos(theta) * sin(phi);
    float z = radio * sin(theta);
    float msx= screenX(x,y,z);
    float msy= screenY(x,y,z);

    float xo = radio * cos(thetaff) * cos(phff);
    float yo = radio * cos(thetaff) * sin(phff);
    float zo = radio * sin(thetaff);

    float xb = xo * largo;
    float yb = yo * largo;
    float zb = zo * largo;
    
    offscreen.beginShape(LINES);
    offscreen.stroke(0);
    offscreen.vertex(x,y,z);
    offscreen.stroke(200,150);
    offscreen.vertex(xb,yb,zb);
    offscreen.endShape();
  }
} 

thank for making this lib, it's very useful for me..

this works for me on windows
Code:

import processing.opengl.*;
import codeanticode.glgraphics.*;
import codeanticode.gsvideo.*;
import deadpixel.keystone.*;
GSMovie myMovie;
GLTexture tex;
Keystone ks;
CornerPinSurface surface;
int w=160,h=120;
void setup() {
  size(1024, 768, GLConstants.GLGRAPHICS);
  tex = new GLTexture(this,w,h);  
  ks = new Keystone(this);
  surface = ks.createCornerPinSurface(w, h, 20);
  myMovie = new GSMovie(this, "station.mov");
  myMovie.loop();
}

void movieEvent(GSMovie myMovie) {
  myMovie.read();
}

void draw() {
  background(0);
  tex.putPixelsIntoTexture(myMovie);
  surface.render(tex);
}
 

btw. great LIB!!! Thanks