A Raytracer for the Compact Framework

using System;
using System.Collections;

namespace raytracer
{
	/// <summary>
	/// raytracing class
	/// </summary>
	public class raytrace
	{
		const int maxobjs=16;

		public raytrace()
		{
			// allocate lists
			m_objects=new objbase [maxobjs];
			m_lightman=new lightmanager();
			m_pos=0;
		}

		public void addobject(objbase obj)
		{
			if(m_pos==maxobjs-1)
				return;

			m_objects[m_pos++]=obj;
		}

		public void addlight(light lgt)
		{
			m_lightman.addlight(lgt);
		}

		public colour getcolourpos(int x,int y)
		{
			vector pos=new vector((float)x,(float)y,100.0f);
			vector eye=new vector(0.0f,0.0f,0.0f);

			ray iray=new ray();
			iray.OriginValue=pos;
			iray.NormalValue=pos-eye;
			
			return shootray(iray);
		}

		private colour shootray(ray iray)
		{
			// allocate colour
			colour col=new colour();

			// closest object
			objbase obj=new objbase();
			IntersectInfo info=new IntersectInfo();

			// test whether ray intersects an object
			if(!intersectiontest(iray,ref obj,ref info))
			{
				col.toblack();
				return col;
			}

			// get the lit colour
			colour litcol=getlitcolour(obj,info,iray);

			// set starting colour
//			col=info.col;
			// light it
//			col*=litcol;

			// limit colour to sensible levels
			litcol.limit();

			return litcol;
		}

		private colour getlitcolour(objbase obj,IntersectInfo info,ray iray)
		{
			// run through the lights
			colour litcol=new colour();
			litcol.toblack();

			for(int lct=0; lct<m_lightman.getnumlights(); lct++)
			{
				// get ray from light to object
				ray lray=m_lightman.getray(lct,info.pos);

				objbase tempobj=new objbase();
				IntersectInfo tempinfo=new IntersectInfo();

				// is there any closer object?
				intersectiontest(lray,ref tempobj,ref tempinfo);

				// no
				if(obj.Equals(tempobj))
					litcol+=m_lightman.getlitcolour(lct,info.pos,info.col,info.normal,obj.ReflectValue,iray.OriginValue);
			}

			return litcol;
		}

		private bool intersectiontest(ray iray,ref objbase closest,ref IntersectInfo info)
		{
			// are there any objects?
			if(m_pos==0)
				return false;

			// set to a large value
			float dist=10000000.0f;

			for(int ct=0; ct<m_pos; ct++)
			{
				// get the present object
				objbase obj=m_objects[ct];

				// test intersection
				IntersectInfo test=obj.intersect(iray);

				// did the ray hit?
				if(test.hit==true)
				{
					// calculate the distance
					float objdist=iray.calcdistvalue(test.pos);

					// is it closer than the last?
					if(objdist<dist)
					{
						dist=objdist;
						closest=obj;
						info=test;
					}
				}
			}
			
			// did the ray hit?
			if(dist==10000000.0f)
				return false;
			else
				return true;
		}

		private int				m_pos;		// position in array
		private objbase	[]		m_objects;	// object list
		private lightmanager	m_lightman;	// light manager
	}
}