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@kechol
Created December 18, 2011 10:01
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ICGで作成したRayTraceのコード
// The main ray tracer.
#pragma warning (disable: 4786)
#include "RayTracer.h"
#include "scene/light.h"
#include "scene/material.h"
#include "scene/ray.h"
#include "parser/Tokenizer.h"
#include "parser/Parser.h"
#include "ui/TraceUI.h"
#include <cmath>
#include <algorithm>
extern TraceUI* traceUI;
#include <iostream>
#include <fstream>
using namespace std;
// Use this variable to decide if you want to print out
// debugging messages. Gets set in the "trace single ray" mode
// in TraceGLWindow, for example.
bool debugMode = false;
// Trace a top-level ray through normalized window coordinates (x,y)
// through the projection plane, and out into the scene. All we do is
// enter the main ray-tracing method, getting things started by plugging
// in an initial ray weight of (0.0,0.0,0.0) and an initial recursion depth of 0.
Vec3d RayTracer::trace( double x, double y )
{
/* Simple trace
// Clear out the ray cache in the scene for debugging purposes,
scene->intersectCache.clear();
ray r( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY );
scene->getCamera().rayThrough( x,y,r );
Vec3d ret = traceRay( r, Vec3d(1.0,1.0,1.0), 0 );
ret.clamp();
return ret;
*/
// AntiAliasing
// Clear out the ray cache in the scene for debugging purposes,
scene->intersectCache.clear();
ray r( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY );
scene->getCamera().rayThrough( x,y,r );
Vec3d ret = traceRay( r, Vec3d(1.0,1.0,1.0), 0 );
ret.clamp();
double gridsize = 0.5; //スーパーサンプリングする領域サイズ(1画素=1)
double x_right = x + gridsize/double(buffer_width);
if(x_right > 1) x_right = 1;
double x_left = x - gridsize/double(buffer_width);
if(x_left < 0) x_left = 0;
double y_up = y + gridsize/double(buffer_height);
if(y_up > 1) y_up = 1;
double y_down = y - gridsize/double(buffer_height);
if(y_down < 0) y_down = 0;
ray AA1( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY);
scene->getCamera().rayThrough( x_right,y_up,AA1 );
Vec3d retAA1 = traceRay( AA1, Vec3d(1.0,1.0,1.0), 0);
retAA1.clamp();
//右下
ray AA2( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY);
scene->getCamera().rayThrough( x_right,y_down,AA2 );
Vec3d retAA2 = traceRay( AA2, Vec3d(1.0,1.0,1.0), 0);
retAA2.clamp();
//左上
ray AA3( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY);
scene->getCamera().rayThrough( x_left,y_up,AA3 );
Vec3d retAA3 = traceRay( AA3, Vec3d(1.0,1.0,1.0), 0);
retAA3.clamp();
//左下
ray AA4( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY);
scene->getCamera().rayThrough( x_left,y_down,AA4 );
Vec3d retAA4 = traceRay( AA4, Vec3d(1.0,1.0,1.0), 0);
retAA4.clamp();
//右
ray AA5( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY);
scene->getCamera().rayThrough( x_right,y,AA5 );
Vec3d retAA5 = traceRay( AA5, Vec3d(1.0,1.0,1.0), 0);
retAA5.clamp();
//左
ray AA6( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY);
scene->getCamera().rayThrough( x_left,y,AA6 );
Vec3d retAA6 = traceRay( AA6, Vec3d(1.0,1.0,1.0), 0);
retAA6.clamp();
//上
ray AA7( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY);
scene->getCamera().rayThrough( x,y_up,AA7 );
Vec3d retAA7 = traceRay( AA7, Vec3d(1.0,1.0,1.0), 0);
retAA7.clamp();
//下
ray AA8( Vec3d(0,0,0), Vec3d(0,0,0), ray::VISIBILITY);
scene->getCamera().rayThrough( x,y_down,AA8 );
Vec3d retAA8 = traceRay( AA8, Vec3d(1.0,1.0,1.0), 0);
retAA8.clamp();
ret = (ret + retAA1 + retAA2 + retAA3 + retAA4 + retAA5 + retAA6 + retAA7 + retAA8) / 9; //平均をとる
return ret;
}
// Do recursive ray tracing! You'll want to insert a lot of code here
// (or places called from here) to handle reflection, refraction, etc etc.
Vec3d RayTracer::traceRay( const ray& r, const Vec3d& thresh, int depth )
{
isect i;
if( scene->intersect( r, i ) ) {
// YOUR CODE HERE
// An intersection occured! We've got work to do. For now,
// this code gets the material for the surface that was intersected,
// and asks that material to provide a color for the ray.
// This is a great place to insert code for recursive ray tracing.
// Instead of just returning the result of shade(), add some
// more steps: add in the contributions from reflected and refracted
// rays.
const Material& m=i.getMaterial(); // 交差した物体のパラメータ取得用
Vec3d ret = m.shade(scene, r, i); // 返り値の初期値にシェーディングの値を入れる
if ( depth < traceUI->getDepth() ) { // 再帰深度とスライダーの値を比較
Vec3d kr = m.kr(i); // 反射の係数
Vec3d kt = m.kt(i); // 透過の係数
Vec3d d = r.getDirection();
Vec3d norm = i.N;
if (d * i.N > 0.0) {
norm = -norm; // 物体内からのRayの場合
}
// reflection
Vec3d reflect(0.0, 0.0, 0.0); // 光源から反射する鏡面光の値
double cosin = -d * norm;
Vec3d dd = cosin * norm + d; //d'
Vec3d rd = -d + 2 * dd; //R
rd.normalize();
if (!(kr.iszero())) { // 反射係数が0かチェック
ray rr( r.at(i.t-RAY_EPSILON), rd, ray::REFLECTION );
reflect = traceRay(rr, thresh, depth+1); // 深度を深めて再帰計算
ret += prod( kr, reflect );
}
// transmission
Vec3d transmit(0.0, 0.0, 0.0); // 屈折するRayの返り値
if (!(kt.iszero())) { // 反射係数が0かチェック
double tantd2 = pow(m.index(i), 2) - dd.length2();
//(n2/n1 - sin(theta) > 0) で条件分岐
if(tantd2 > RAY_EPSILON) {
Vec3d td = -norm + dd / sqrt(tantd2); //d't
td.normalize();
ray rr( r.at(i.t+RAY_EPSILON), td, ray::REFRACTION );
transmit = traceRay(rr, thresh, depth+1); // 深度を深めて再帰計算
ret += prod(kt, transmit);
} else { //全反射の場合
ret += prod(kt, reflect);
}
}
}
return ret;
} else {
// No intersection. This ray travels to infinity, so we color
// it according to the background color, which in this (simple) case
// is just black.
return Vec3d( 0.0, 0.0, 0.0 );
}
}
RayTracer::RayTracer()
: scene( 0 ), buffer( 0 ), buffer_width( 256 ), buffer_height( 256 ), m_bBufferReady( false )
{
}
RayTracer::~RayTracer()
{
delete scene;
delete [] buffer;
}
void RayTracer::getBuffer( unsigned char *&buf, int &w, int &h )
{
buf = buffer;
w = buffer_width;
h = buffer_height;
}
double RayTracer::aspectRatio()
{
return sceneLoaded() ? scene->getCamera().getAspectRatio() : 1;
}
bool RayTracer::loadScene( char* fn )
{
ifstream ifs( fn );
if( !ifs ) {
string msg( "Error: couldn't read scene file " );
msg.append( fn );
traceUI->alert( msg );
return false;
}
// Strip off filename, leaving only the path:
string path( fn );
if( path.find_last_of( "\\/" ) == string::npos )
path = ".";
else
path = path.substr(0, path.find_last_of( "\\/" ));
// Call this with 'true' for debug output from the tokenizer
Tokenizer tokenizer( ifs, false );
Parser parser( tokenizer, path );
try {
delete scene;
scene = 0;
scene = parser.parseScene();
}
catch( SyntaxErrorException& pe ) {
traceUI->alert( pe.formattedMessage() );
return false;
}
catch( ParserException& pe ) {
string msg( "Parser: fatal exception " );
msg.append( pe.message() );
traceUI->alert( msg );
return false;
}
catch( TextureMapException e ) {
string msg( "Texture mapping exception: " );
msg.append( e.message() );
traceUI->alert( msg );
return false;
}
if( ! sceneLoaded() )
return false;
// Initialize the scene's BSP tree
scene->initBSPTree();
return true;
}
void RayTracer::traceSetup( int w, int h )
{
if( buffer_width != w || buffer_height != h )
{
buffer_width = w;
buffer_height = h;
bufferSize = buffer_width * buffer_height * 3;
delete [] buffer;
buffer = new unsigned char[ bufferSize ];
}
memset( buffer, 0, w*h*3 );
m_bBufferReady = true;
}
void RayTracer::tracePixel( int i, int j )
{
Vec3d col;
if( ! sceneLoaded() )
return;
double x = double(i)/double(buffer_width);
double y = double(j)/double(buffer_height);
col = trace( x,y );
unsigned char *pixel = buffer + ( i + j * buffer_width ) * 3;
pixel[0] = (int)( 255.0 * col[0]);
pixel[1] = (int)( 255.0 * col[1]);
pixel[2] = (int)( 255.0 * col[2]);
}
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