//-----------------------------------------------------------------------
void LiSPSMShadowCameraSetup::getShadowCamera (const SceneManager *sm, const Camera *cam,
const Viewport *vp, const Light *light, Camera *texCam) const
{
// check availability - viewport not needed
OgreAssert(sm != NULL, "SceneManager is NULL");
OgreAssert(cam != NULL, "Camera (viewer) is NULL");
OgreAssert(light != NULL, "Light is NULL");
OgreAssert(texCam != NULL, "Camera (texture) is NULL");
mLightFrustumCameraCalculated = false;
// calculate standard shadow mapping matrix
Matrix4 LView, LProj;
calculateShadowMappingMatrix(*sm, *cam, *light, &LView, &LProj, NULL);
// build scene bounding box
const VisibleObjectsBoundsInfo& visInfo = sm->getShadowCasterBoundsInfo(light);
AxisAlignedBox sceneBB = visInfo.aabb;
sceneBB.merge(sm->getVisibleObjectsBoundsInfo(cam).aabb);
sceneBB.merge(cam->getDerivedPosition());
// in case the sceneBB is empty (e.g. nothing visible to the cam) simply
// return the standard shadow mapping matrix
if (sceneBB.isNull())
{
texCam->setCustomViewMatrix(true, LView);
texCam->setCustomProjectionMatrix(true, LProj);
return;
}
// calculate the intersection body B
mPointListBodyB.reset();
calculateB(*sm, *cam, *light, sceneBB, &mPointListBodyB);
// in case the bodyB is empty (e.g. nothing visible to the light or the cam)
// simply return the standard shadow mapping matrix
if (mPointListBodyB.getPointCount() == 0)
{
texCam->setCustomViewMatrix(true, LView);
texCam->setCustomProjectionMatrix(true, LProj);
return;
}
// transform to light space: y -> -z, z -> y
LProj = msNormalToLightSpace * LProj;
// calculate LVS so it does not need to be calculated twice
// calculate the body L \cap V \cap S to make sure all returned points are in
// front of the camera
calculateLVS(*sm, *cam, *light, sceneBB, &mPointListBodyLVS);
// fetch the viewing direction
const Vector3 viewDir = getLSProjViewDir(LProj * LView, *cam, mPointListBodyLVS);
// The light space will be rotated in such a way, that the projected light view
// always points upwards, so the up-vector is the y-axis (we already prepared the
// light space for this usage).The transformation matrix is set up with the
// following parameters:
// - position is the origin
// - the view direction is the calculated viewDir
// - the up vector is the y-axis
LProj = buildViewMatrix(Vector3::ZERO, viewDir, Vector3::UNIT_Y) * LProj;
// calculate LiSPSM projection
LProj = calculateLiSPSM(LProj * LView, mPointListBodyB, mPointListBodyLVS, *sm, *cam, *light) * LProj;
// map bodyB to unit cube
LProj = transformToUnitCube(LProj * LView, mPointListBodyB) * LProj;
// transform from light space to normal space: y -> z, z -> -y
LProj = msLightSpaceToNormal * LProj;
// LView = Lv^-1
// LProj = Switch_{-ls} * FocusBody * P * L_r * Switch_{ls} * L_p
texCam->setCustomViewMatrix(true, LView);
texCam->setCustomProjectionMatrix(true, LProj);
}
void DiFocusedShadowPolicy::getShadowCamera (const DiSceneManager *sm, const DiCamera *cam,
const DiViewport *vp, const DiLight *light, DiCamera *texCam, size_t iteration) const
{
// check availability - viewport not needed
DI_ASSERT_MESSAGE(sm != NULL, "SceneManager is NULL");
DI_ASSERT_MESSAGE(cam != NULL, "Camera (viewer) is NULL");
DI_ASSERT_MESSAGE(light != NULL, "Light is NULL");
DI_ASSERT_MESSAGE(texCam != NULL, "Camera (texture) is NULL");
mLightFrustumCameraCalculated = false;
texCam->SetNearClipDistance(light->DeriveShadowNearClipDistance(cam));
texCam->SetFarClipDistance(light->DeriveShadowFarClipDistance(cam));
// calculate standard shadow mapping matrix
DiMat4 LView, LProj;
calculateShadowMappingMatrix(*sm, *cam, *light, &LView, &LProj, NULL);
// build scene bounding box
auto& visInfo = texCam->GetVisBoundsInfo();
DiAABB sceneBB = visInfo.aabb;
DiAABB receiverAABB = cam->GetVisBoundsInfo().receiverAabb;
sceneBB.Merge(receiverAABB);
sceneBB.Merge(cam->GetDerivedPosition());
// in case the sceneBB is empty (e.g. nothing visible to the cam) simply
// return the standard shadow mapping matrix
if (sceneBB.IsNull())
{
texCam->SetCustomViewMatrix(true, LView);
texCam->SetCustomProjectionMatrix(true, LProj);
return;
}
// calculate the intersection body B
mPointListBodyB.reset();
calculateB(*sm, *cam, *light, sceneBB, receiverAABB, &mPointListBodyB);
// in case the bodyB is empty (e.g. nothing visible to the light or the cam)
// simply return the standard shadow mapping matrix
if (mPointListBodyB.getPointCount() == 0)
{
texCam->SetCustomViewMatrix(true, LView);
texCam->SetCustomProjectionMatrix(true, LProj);
return;
}
// transform to light space: y -> -z, z -> y
LProj = msNormalToLightSpace * LProj;
// calculate LVS so it does not need to be calculated twice
// calculate the body L \cap V \cap S to make sure all returned points are in
// front of the camera
mPointListBodyLVS.reset();
calculateLVS(*sm, *cam, *light, sceneBB, &mPointListBodyLVS);
// fetch the viewing direction
const DiVec3 viewDir = getLSProjViewDir(LProj * LView, *cam, mPointListBodyLVS);
// The light space will be rotated in such a way, that the projected light view
// always points upwards, so the up-vector is the y-axis (we already prepared the
// light space for this usage).The transformation matrix is set up with the
// following parameters:
// - position is the origin
// - the view direction is the calculated viewDir
// - the up vector is the y-axis
LProj = buildViewMatrix(DiVec3::ZERO, viewDir, DiVec3::UNIT_Y) * LProj;
// map bodyB to unit cube
LProj = transformToUnitCube(LProj * LView, mPointListBodyB) * LProj;
// transform from light space to normal space: y -> z, z -> -y
LProj = msLightSpaceToNormal * LProj;
// set the two custom matrices
texCam->SetCustomViewMatrix(true, LView);
texCam->SetCustomProjectionMatrix(true, LProj);
}
