khanat-opennel-code/code/nel/src/3d/shadow_map.cpp
2010-05-06 02:08:41 +02:00

231 lines
7.4 KiB
C++

// NeL - MMORPG Framework <http://dev.ryzom.com/projects/nel/>
// Copyright (C) 2010 Winch Gate Property Limited
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
#include "std3d.h"
#include "nel/3d/shadow_map.h"
#include "nel/3d/texture_mem.h"
#include "nel/misc/common.h"
#include "nel/3d/driver.h"
#include "nel/3d/shadow_map_manager.h"
using namespace std;
using namespace NLMISC;
namespace NL3D {
// ***************************************************************************
CShadowMap::CShadowMap(CShadowMapManager *smm)
{
nlassert(smm);
_ShadowMapManager= smm;
_TextSize= 0;
LastGenerationFrame= 0;
DistanceFade= 0;
TemporalOutScreenFade= 0;
TemporalInScreenFade= 0;
_FadeAround= 0;
_FinalFade= 1;
// see doc why 1.
InScreenFadeAccum= 1;
}
// ***************************************************************************
CShadowMap::~CShadowMap()
{
resetTexture();
}
// ***************************************************************************
void CShadowMap::initTexture(uint textSize)
{
textSize= max(textSize, 2U);
// if same size than setup, quit
if(_TextSize==textSize)
return;
resetTexture();
textSize= raiseToNextPowerOf2(textSize);
_TextSize= textSize;
// Allocate in the Manager.
_Texture= _ShadowMapManager->allocateTexture(_TextSize);
// Since our texture has changed, it is no more valid. reset counter.
LastGenerationFrame= 0;
}
// ***************************************************************************
void CShadowMap::resetTexture()
{
// release the SmartPtr
if(_Texture)
{
_ShadowMapManager->releaseTexture(_Texture);
_Texture= NULL;
}
_TextSize= 0;
}
// ***************************************************************************
void CShadowMap::buildClipInfoFromMatrix()
{
CVector vi= LocalProjectionMatrix.getI();
CVector vj= LocalProjectionMatrix.getJ();
CVector vk= LocalProjectionMatrix.getK();
CVector vp= LocalProjectionMatrix.getPos();
// **** Compute the planes.
LocalClipPlanes.resize(6);
// The plane 0 is the back plane.
LocalClipPlanes[0].make(-vj, vp);
// Left and botom plane.
LocalClipPlanes[1].make(-vi, vp);
LocalClipPlanes[2].make(-vk, vp);
// Right and top plane.
LocalClipPlanes[3].make(vi, vp + vi);
LocalClipPlanes[4].make(vk, vp + vk);
// Front plane.
LocalClipPlanes[5].make(vj, vp + vj);
// **** Compute the AA bounding box.
LocalBoundingBox.setHalfSize(CVector::Null);
CVector p0= vp;
CVector p1= p0 + vi + vj + vk;
LocalBoundingBox.setCenter(p0);
LocalBoundingBox.extend(p0 + vi);
LocalBoundingBox.extend(p0 + vj);
LocalBoundingBox.extend(p0 + vk);
LocalBoundingBox.extend(p1 - vi);
LocalBoundingBox.extend(p1 - vj);
LocalBoundingBox.extend(p1 - vk);
LocalBoundingBox.extend(p1);
}
// ***************************************************************************
void CShadowMap::buildCasterCameraMatrix(const CVector &lightDir, const CMatrix &localPosMatrix, const CAABBox &bbShape, CMatrix &cameraMatrix)
{
// compute the orthogonal LightSpace camera matrix. Remind that J look forward and K is up here.
cameraMatrix.setArbitraryRotJ(lightDir);
CAABBox bbLocal;
bbLocal= CAABBox::transformAABBox(cameraMatrix.inverted() * localPosMatrix, bbShape);
// Enlarge for 1 pixel left and right.
float scaleSize= (float)getTextureSize();
scaleSize= (scaleSize+2)/scaleSize;
CVector hs= bbLocal.getHalfSize();
hs.x*= scaleSize;
hs.z*= scaleSize;
// TestUniform
/*float maxLen= max(hs.x, hs.y);
maxLen= max(maxLen, hs.z);
hs.x= hs.y= hs.z= maxLen;*/
// EndTestUniform
bbLocal.setHalfSize(hs);
// setup the orthogonal camera Matrix so that it includes all the BBox
cameraMatrix.translate(bbLocal.getMin());
CVector vi= cameraMatrix.getI() * bbLocal.getSize().x;
CVector vj= cameraMatrix.getJ() * bbLocal.getSize().y;
CVector vk= cameraMatrix.getK() * bbLocal.getSize().z;
cameraMatrix.setRot(vi,vj,vk);
}
// ***************************************************************************
void CShadowMap::buildProjectionInfos(const CMatrix &cameraMatrix, const CVector &backPoint, float shadowMaxDepth)
{
// Modify the cameraMatrix to define the Aera of Shadow.
CVector projp= cameraMatrix.getPos();
CVector proji= cameraMatrix.getI();
CVector projj= cameraMatrix.getJ();
CVector projk= cameraMatrix.getK();
// modify the J vector so that it gets the Wanted Len
CVector vj= projj.normed();
projj= vj*shadowMaxDepth;
// Must move Pos so that the IK plane include the backPoint
projp+= (backPoint*vj-projp*vj) * vj;
// set the matrix
LocalProjectionMatrix.setRot(proji, projj, projk);
LocalProjectionMatrix.setPos(projp);
// compute The clipPlanes and bbox.
buildClipInfoFromMatrix();
}
// ***************************************************************************
void CShadowMap::processFades()
{
clamp(DistanceFade, 0.f, 1.f);
clamp(TemporalOutScreenFade, 0.f, 1.f);
clamp(TemporalInScreenFade, 0.f, 1.f);
_FadeAround= max(DistanceFade, TemporalOutScreenFade);
_FinalFade= max(_FadeAround, TemporalInScreenFade);
/* if the fadeAround is 1, then release the texture
Don't take _FinalFade because this last may change too much cause of TemporalInScreenFade.
While FadeAround is somewhat stable (as entities and the camera don't move too much),
TemporalInScreenFade is dependent of camera rotation.
=> _FinalFade allow to not draw too much shadows (CPU gain),
while FadeAround allow in addition the capacity to not use too much texture memory
*/
if(getFadeAround()==1)
resetTexture();
}
// ***************************************************************************
CShadowMapProjector::CShadowMapProjector()
{
// Trans matrix from Nel basis (Z up) to UVW basis (V up)
_XYZToUWVMatrix.setRot(CVector::I, CVector::K, CVector::J, true);
// Trans Matrix so Y is now the U (for clamp map).
_XYZToWUVMatrix.setRot(CVector::K, CVector::I, CVector::J, true);
}
// ***************************************************************************
void CShadowMapProjector::setWorldSpaceTextMat(const CMatrix &ws)
{
_WsTextMat= ws;
}
// ***************************************************************************
void CShadowMapProjector::applyToMaterial(const CMatrix &receiverWorldMatrix, CMaterial &material)
{
CMatrix osTextMat;
osTextMat.setMulMatrix(_WsTextMat, receiverWorldMatrix);
/* Set the TextureMatrix for ShadowMap projection so that UVW= mat * XYZ.
its osTextMat but must rotate so Z map to V
*/
material.setUserTexMat(0, _XYZToUWVMatrix * osTextMat);
/* Set the TextureMatrix for ClampMap projection so that UVW= mat * XYZ.
its osTextMat but must rotate so Y map to U
*/
material.setUserTexMat(1, _XYZToWUVMatrix * osTextMat);
}
} // NL3D