NeL: NL3D::CPatchDLMPointLight class Reference

Detailed Description

Author:

Lionel Berenguier

+Nevrax France

Date:

2002

+ +

+Definition at line 55 of file patchdlm_context.h. + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +


Public Member Functions
void	compile (const CPointLight &pl, NLMISC::CRGBA landDiffMat, float maxAttEnd=30.f)
Data Fields
float	AttMax
float	AttMin
float	B
NLMISC::CAABBox	BBox
NLMISC::CBSphere	BSphere
float	CosMax
float	CosMin
CVector	Dir
float	G
bool	IsSpot
float	OOAttDelta
float	OOCosDelta
CVector	Pos
float	R

Member Function Documentation

+ + + + +

+ + + + + + + + + + + + + + + + + + + + + + + + + +

void NL3D::CPatchDLMPointLight::compile	(	const CPointLight &	pl,
		NLMISC::CRGBA	landDiffMat,
		float	maxAttEnd = 30.f
	)

+ + + + + +

+ +

+Definition at line 52 of file patchdlm_context.cpp. +

00053 {
+00054         nlassert(maxAttEnd>0);
+00055 
+00056         // copy color
+00057         R= (float) (( pl.getDiffuse().R*(landDiffMat.R+1) ) >>8);
+00058         G= (float) (( pl.getDiffuse().G*(landDiffMat.G+1) ) >>8);
+00059         B= (float) (( pl.getDiffuse().B*(landDiffMat.B+1) ) >>8);
+00060         // Copy Spot/Pos/Dir.
+00061         IsSpot= pl.getType() == CPointLight::SpotLight;
+00062         Pos= pl.getPosition();
+00063         Dir= pl.getSpotDirection();
+00064         
+00065         // compute spot params
+00066         if(IsSpot)
+00067         {
+00068                 CosMax= cosf(pl.getSpotAngleBegin());
+00069                 CosMin= cosf(pl.getSpotAngleEnd());
+00070         }
+00071         else
+00072         {
+00073                 // with tesse Values, we have always (cosSpot-CosMin) * OOCosDelta > 1.0f
+00074                 CosMax= -1;
+00075                 CosMin= -2;
+00076         }
+00077         OOCosDelta= 1.f / (CosMax-CosMin);
+00078 
+00079         // compute att params
+00080         AttMax= pl.getAttenuationEnd();
+00081         AttMin= pl.getAttenuationBegin();
+00082         // infinite pointLight?
+00083         if(AttMax==0)
+00084         {
+00085                 AttMax= maxAttEnd;
+00086                 AttMin= maxAttEnd*0.99f;
+00087         }
+00088         // To big pointLigt?
+00089         else if(AttMax>maxAttEnd)
+00090         {
+00091                 AttMax= maxAttEnd;
+00092                 AttMin= min(AttMin, maxAttEnd*0.99f);
+00093         }
+00094         // compile distance
+00095         OOAttDelta= 1.f / (AttMin-AttMax);
+00096 
+00097 
+00098         // Compute bounding sphere.
+00099         // If not a spot or if angleMin>Pi/2
+00100         if(!IsSpot || CosMin<0)
+00101         {
+00102                 // Take sphere of pointlight sphere
+00103                 BSphere.Center= Pos;
+00104                 BSphere.Radius= AttMax;
+00105                 // The bbox englobe the sphere.
+00106                 BBox.setCenter(Pos);
+00107                 BBox.setHalfSize(CVector(AttMax, AttMax, AttMax));
+00108         }
+00109         else
+00110         {
+00111                 // Compute BSphere.
+00112                 //==============
+00113 
+00114                 // compute sinus of AngleMin
+00115                 float   sinMin= sqrtf(1-sqr(CosMin));
+00116 
+00117                 // Test 2 centers: Center of radius along Dir: Pos+Dir*AttMax/2, and intersection of end cone with line (Pos,Dir)
+00118                 // Don't know why but I think they are sufficiently good :)
+00119                 // See below for computing of those centers.
+00120 
+00121                 /* compute radius of each sphere by taking max of 3 distances: distance to spotLight center, distance
+00122                         to spotLight forward extremity, and distance to spotLight circle interstion Cone/Sphere. (named DCCS)
+00123                         NB: Do the compute with radius=1 at first, then multiply later.
+00124                 */
+00125                 float   radius1= 0.5f;          // =max(0.5, 0.5); max distance to spot center and extremity center :)
+00126                 // for distance DCCS, this is the hypothenuse of (cosMin-0.5) + sinMin.
+00127                 float   dccs= sqrtf( sqr(CosMin-0.5f) + sqr(sinMin));
+00128                 // take the bigger.
+00129                 radius1= max(radius1, dccs );
+00130 
+00131                 // Same reasoning for center2.
+00132                 float   radius2= max(CosMin, 1-CosMin); // max distance to spot center and extremity center :)
+00133                 // for distance DCCS, it is simply sinMin!!
+00134                 dccs= sinMin;
+00135                 // take the bigger.
+00136                 radius2= max(radius2, dccs );
+00137 
+00138 
+00139                 // Then take the center which gives the smaller sphere
+00140                 if(radius1<radius2)
+00141                 {
+00142                         BSphere.Center= Pos + (Dir*0.5f*AttMax);
+00143                         // radius1 E [0,1], must take real size.
+00144                         BSphere.Radius= radius1 * AttMax;
+00145                 }
+00146                 else
+00147                 {
+00148                         BSphere.Center= Pos + (Dir*CosMin*AttMax);
+00149                         // radius2 E [0,1], must take real size.
+00150                         BSphere.Radius= radius2 * AttMax;
+00151                 }
+00152 
+00153 
+00154                 // Compute BBox.
+00155                 //==============
+00156                 
+00157                 // just take bbox of the sphere, even if not optimal.
+00158                 BBox.setCenter(BSphere.Center);
+00159                 float   rad= BSphere.Radius;
+00160                 BBox.setHalfSize( CVector(rad, rad, rad) );
+00161         }
+00162 }
+

Field Documentation