//created=03 Sep 07
//description=Shadow billboards projected onto a planar surface.
//title=Shadow
//publish=true
 
import InterpolatedVar.*;
import Raytracing.*;
import Tuple.*;
 
int frame =0;
 
Vector cast;
float az = 0, el =0;
 
float jx=0,jy=0;
PImage a,b,c;
 
int showHints = 0;
 
InterpolatedVar ilx,ilz,ily; 
 
Tuple3f light = new Tuple3f(0,-200,200);
Plane ground = new Plane(0,50,0,0,1,0);
 
float cx = 0,cy = 100, cz = 45;
float lx = 0.0, ly = -1, ez = 45;        
                
void setup() 
{ 
 
  size( 550, 300, P3D); 
    hint(g.ENABLE_ACCURATE_TEXTURES) ;
  ilx = new SOLagInterpolatedVar(this,0,12,6);
  ily = new SOLagInterpolatedVar(this,-100,12,6);
  ilz = new SOLagInterpolatedVar(this,200,12,6);
 
 
 
  a = loadImage("poenderous.png");
  c = loadImage("poenderousShadow.png");
  cast = new Vector();
 
  for (int i=0; i < 40; i++){
    cast.add(new Guy());
  }
 
  textureMode(NORMALIZED);
} 
 
void draw(){ 
  
  frame--;
 
  background( 225,225,235); 
 
  hint(ENABLE_DEPTH_SORT);
 
  if (frame < 0) {
    frame = (int)random(60,240);
    ilx.setVal(random(-300,300));
    ily.setVal(random(-300,-100));
    ilz.setVal(random(-300,300));
  }
 
  
  light.x = ilx.getVal();
  light.z = ilz.getVal();
 
camera(   cx, -ez ,  cy, cx + lx, -cz , cy + ly, 0, 1, 0);
fill(200);
 
noStroke();
 
 
 
Guy curr;
for (int i=0; i < cast.size(); i++){
  curr = (Guy)cast.elementAt(i);
  curr.draw();
 
}
 
//draw the light
pushMatrix();
translate(light.x,light.y,light.z);
fill(255);
sphere(5);
popMatrix();
 
  if(keyPressed) {
    float speed = 5;
    if(key == 'w') {
      cx += speed*lx;
      cy += speed*ly;
 
    }
    if(key == 's') {
      cx -= speed*lx;
      cy -= speed*ly;
 
    }   
    if(key == 'd') {
      cx -= speed*ly;
      cy += speed*lx;
 
    } 
     if(key == 'a') {
      cx += speed*ly;
      cy -= speed*lx;
 
    }  
 
     if(key == 'r') {
      ez +=1;
      cz +=1;
    }  
     if(key == 'f') {
      if (ez > -50){
        ez -=1;
        cz -=1;
      }
    }
 
    
    if(key == 'q') {
      float tr = -.1;
      lx = lx*cos(tr) - ly*sin(tr);
      ly = lx*sin(tr) + ly*cos(tr);
      
      float norm = sqrt(lx*lx + ly*ly);
      lx/=norm;
      ly/=norm;
      
    }
    if(key == 'e') {
      float tr = .1;
      lx = lx*cos(tr) - ly*sin(tr);
      ly = lx*sin(tr) + ly*cos(tr);
      
      float norm = sqrt(lx*lx + ly*ly);
      lx/=norm;
      ly/=norm;
    }
    
    }
 
} 
 
void keyPressed(){
     if(key == 'h') {
      showHints = 1 - showHints;
 
    }
 
}
void mouseDragged(){
  if (mouseButton == LEFT){
     cz -= (mouseY-pmouseY)/75.0;
  
      float tr = (mouseX-pmouseX)/100.0;
      lx = lx*cos(tr) - ly*sin(tr);
      ly = lx*sin(tr) + ly*cos(tr);
      
      float norm = sqrt(lx*lx + ly*ly);
      lx/=norm;
      ly/=norm;
  }
  else{
    float dy = mouseY-pmouseY;
    if (ez > -50 || dy > 0){
      cz += dy; 
      ez += dy;
    }
  }
 
}
  
 
class Guy{
 
  PImage tex,texs;
  float x,y;
  
    
  public Guy(){
 
    x = random(-400,400);
    y = random(-400,400);
 
  }
 
  void draw(){
 
    pushMatrix();
 
    translate( x,0,y);
    noStroke();
    fill(0,255);
 
    beginShape();
    texture(a);
      vertex(0, 0, 0, 0);
      vertex(20, 0, 1, 0);
      vertex(20, 50, 1, 1);
      vertex(0, 50, 0, 1);
    endShape();
 
    popMatrix();
 
 
    //lets collide the shoulder with the light
    stroke(0);
    Ray isect= new Ray();
    
    isect.setPointer(light,new Tuple3f(x,0,y));
    
    //RenderState isect = new RenderState(shadowRay);
    
    ground.intersect(isect);
    Tuple3f gpt = isect.project(isect.distance);
    
    if (showHints == 1){
    beginShape();
      vertex(light.x,light.y,light.z);
      vertex(gpt.x,gpt.y,gpt.z);
    endShape(); 
    }
    isect.setPointer(light,new Tuple3f(x+20,0,y));
    //isect = new RenderState(shadowRay);
    ground.intersect(isect);
    Tuple3f gpt2 = isect.project(isect.distance);
    if (showHints == 1){
    beginShape();
      vertex(light.x,light.y,light.z);
      vertex(gpt2.x,gpt2.y,gpt2.z);
    endShape(); 
    }
    noStroke();
    beginShape();
      texture(c);
      vertex(gpt.x,gpt.y,gpt.z,0,0);
      vertex(gpt2.x,gpt2.y,gpt2.z,1,0);
      vertex(x+20,49,y,1,1);
      vertex(x,49,y,0,1);   
    endShape();
    
 
  }
 
}