//?-----------------------------------------------------------
//?raytracer.cpp
//?2004?-?Jacco?Bikker?-?jacco@bik5.com?-?www.bik5.com?-???<><
//?-----------------------------------------------------------

#include?“raytracer.h“
#include?“scene.h“
#include?“common.h“
#include?“windows.h“
#include?“winbase.h“

namespace?Raytracer?{

Ray::Ray（?vector3&?a_Origin?vector3&?a_Dir?）?:?
	m_Origin（?a_Origin?）?
	m_Direction（?a_Dir?）
{
}

Engine::Engine（）
{
	m_Scene?=?new?Scene（）;
}

Engine::~Engine（）
{
	delete?m_Scene;
}

//?-----------------------------------------------------------
//?Engine::SetTarget
//?Sets?the?render?target?canvas
//?-----------------------------------------------------------
void?Engine::SetTarget（?Pixel*?a_Dest?int?a_Width?int?a_Height?）
{
	//?set?pixel?buffer?address?&?size
	m_Dest?=?a_Dest;
	m_Width?=?a_Width;
	m_Height?=?a_Height;
}

//?-----------------------------------------------------------
//?Engine::Raytrace
//?Naive?ray?tracing:?Intersects?the?ray?with?every?primitive
//?in?the?scene?to?determine?the?closest?intersection
//?-----------------------------------------------------------
Primitive*?Engine::Raytrace（?Ray&?a_Ray?Color&?a_Acc?int?a_Depth?float?a_RIndex?float&?a_Dist?）
{
	if?（a_Depth?>?TRACEDEPTH）?return?0;
	//?trace?primary?ray
	a_Dist?=?1000000.0f;
	vector3?pi;
	Primitive*?prim?=?0;
	int?result;
	//?find?the?nearest?intersection
	for?（?int?s?=?0;?s?GetNrPrimitives（）;?s++?）
	{
		Primitive*?pr?=?m_Scene->GetPrimitive（?s?）;
		int?res;
		if?（res?=?pr->Intersect（?a_Ray?a_Dist?））?
		{
			prim?=?pr;
			result?=?res;?//?0?=?miss?1?=?hit?-1?=?hit?from?inside?primitive
		}
	}
	//?no?hit?terminate?ray
	if?（!prim）?return?0;
	//?handle?intersection
	if?（prim->IsLight（））
	{
		//?we?hit?a?light?stop?tracing
		a_Acc?=?Color（?1?1?1?）;
	}
	else
	{
		//?determine?color?at?point?of?intersection
		pi?=?a_Ray.GetOrigin（）?+?a_Ray.GetDirection（）?*?a_Dist;
		//?trace?lights
		for?（?int?l?=?0;?l?GetNrPrimitives（）;?l++?）
		{
			Primitive*?p?=?m_Scene->GetPrimitive（?l?）;
			if?（p->IsLight（））?
			{
				Primitive*?light?=?p;
				//?calculate?diffuse?shading
				vector3?L?=?（（Sphere*）light）->GetCentre（）?-?pi;
				NORMALIZE（?L?）;
				vector3?N?=?prim->GetNormal（?pi?）;
				if?（prim->GetMaterial（）->GetDiffuse（）?>?0）
				{
					float?dot?=?DOT（?N?L?）;
					if?（dot?>?0）
					{
						float?diff?=?dot?*?prim->GetMaterial（）->GetDiffuse（）;
						//?add?diffuse?component?to?ray?color
						a_Acc?+=?diff?*?prim->GetMaterial（）->GetColor（）?*?light->GetMaterial（）->GetColor（）;
					}
				}
			}
		}
	}
	//?return?pointer?to?primitive?hit?by?primary?ray
	return?prim;
}

//?-----------------------------------------------------------
//?Engine::InitRender
//?Initializes?the?renderer?by?resetting?the?line?/?tile
//?counters?and?precalculating?some?values
//?----------------------------------------------------------

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????3294??2004-09-16?08:47??common.h
?????文件????????4911??2004-09-21?11:03??raytracer.cpp
?????文件????????4185??2004-09-16?08:58??raytracer.dsp
?????文件?????????541??2004-07-08?16:04??raytracer.dsw
?????文件????????1627??2004-09-16?10:58??raytracer.h
?????文件????????3756??2004-09-21?11:04??scene.cpp
?????文件????????3646??2004-09-16?11:10??scene.h
?????文件????????4921??2004-08-30?21:38??surface.cpp
?????文件????????1064??2004-08-30?21:39??surface.h
?????文件????????3974??2004-09-16?08:47??testapp.cpp