void MinimalShadowMap::ViewData::clampProjection
( osg::Matrixd & projection, float new_near, float new_far )
{
double r, l, t, b, n, f;
bool perspective = projection.getFrustum( l, r, b, t, n, f );
if( !perspective && !projection.getOrtho( l, r, b, t, n, f ) )
{
// What to do here ?
osg::notify( osg::WARN )
<< "MinimalShadowMap::clampProjectionFarPlane failed - non standard matrix"
<< std::endl;
} else if( n < new_near || new_far < f ) {
if( n < new_near && new_near < f ) {
if( perspective ) {
l *= new_near / n;
r *= new_near / n;
b *= new_near / n;
t *= new_near / n;
}
n = new_near;
}
if( n < new_far && new_far < f ) {
f = new_far;
}
if( perspective )
projection.makeFrustum( l, r, b, t, n, f );
else
projection.makeOrtho( l, r, b, t, n, f );
}
}
void MinimalShadowMap::ViewData::extendProjection
( osg::Matrixd & projection, osg::Viewport * viewport, const osg::Vec2& margin )
{
double l,r,b,t,n,f;
//osg::Matrix projection = camera.getProjectionMatrix();
bool frustum = projection.getFrustum( l,r,b,t,n,f );
if( !frustum && !projection.getOrtho( l,r,b,t,n,f ) ) {
osg::notify( osg::WARN )
<< " Awkward projection matrix. ComputeExtendedProjection failed"
<< std::endl;
return;
}
osg::Matrix window = viewport->computeWindowMatrix();
osg::Vec3 vMin( viewport->x() - margin.x(),
viewport->y() - margin.y(),
0.0 );
osg::Vec3 vMax( viewport->width() + margin.x() * 2 + vMin.x(),
viewport->height() + margin.y() * 2 + vMin.y(),
0.0 );
osg::Matrix inversePW = osg::Matrix::inverse( projection * window );
vMin = vMin * inversePW;
vMax = vMax * inversePW;
l = vMin.x();
r = vMax.x();
b = vMin.y();
t = vMax.y();
if( frustum )
projection.makeFrustum( l,r,b,t,n,f );
else
projection.makeOrtho( l,r,b,t,n,f );
}
void MinimalShadowMap::ViewData::trimProjection
( osg::Matrixd & projectionMatrix, osg::BoundingBox bb, unsigned int trimMask )
{
#if 1
if( !bb.valid() || !( trimMask & (1|2|4|8|16|32) ) ) return;
double l = -1, r = 1, b = -1, t = 1, n = 1, f = -1;
#if 0
// make sure bounding box does not extend beyond unit frustum clip range
for( int i = 0; i < 3; i ++ ) {
if( bb._min[i] < -1 ) bb._min[i] = -1;
if( bb._max[i] > 1 ) bb._max[i] = 1;
}
#endif
if( trimMask & 1 ) l = bb._min[0];
if( trimMask & 2 ) r = bb._max[0];
if( trimMask & 4 ) b = bb._min[1];
if( trimMask & 8 ) t = bb._max[1];
if( trimMask & 16 ) n = -bb._min[2];
if( trimMask & 32 ) f = -bb._max[2];
projectionMatrix.postMult( osg::Matrix::ortho( l,r,b,t,n,f ) );
#else
if( !bb.valid() || !( trimMask & (1|2|4|8|16|32) ) ) return;
double l, r, t, b, n, f;
bool ortho = projectionMatrix.getOrtho( l, r, b, t, n, f );
if( !ortho && !projectionMatrix.getFrustum( l, r, b, t, n, f ) )
return; // rotated or skewed or other crooked projection - give up
// make sure bounding box does not extend beyond unit frustum clip range
for( int i = 0; i < 3; i ++ ) {
if( bb._min[i] < -1 ) bb._min[i] = -1;
if( bb._max[i] > 1 ) bb._max[i] = 1;
}
osg::Matrix projectionToView = osg::Matrix::inverse( projectionMatrix );
osg::Vec3 min =
osg::Vec3( bb._min[0], bb._min[1], bb._min[2] ) * projectionToView;
osg::Vec3 max =
osg::Vec3( bb._max[0], bb._max[1], bb._max[2] ) * projectionToView;
if( trimMask & 16 ) { // trim near
if( !ortho ) { // recalc frustum corners on new near plane
l *= -min[2] / n;
r *= -min[2] / n;
b *= -min[2] / n;
t *= -min[2] / n;
}
n = -min[2];
}
if( trimMask & 32 ) // trim far
f = -max[2];
if( !ortho ) {
min[0] *= -n / min[2];
min[1] *= -n / min[2];
max[0] *= -n / max[2];
max[1] *= -n / max[2];
}
if( l < r ) { // check for inverted X range
if( l < min[0] && ( trimMask & 1 ) ) l = min[0];
if( r > max[0] && ( trimMask & 2 ) ) r = max[0];
} else {
if( l > min[0] && ( trimMask & 1 ) ) l = min[0];
if( r < max[0] && ( trimMask & 2 ) ) r = max[0];
}
if( b < t ) { // check for inverted Y range
if( b < min[1] && ( trimMask & 4 ) ) b = min[1];
if( t > max[1] && ( trimMask & 8 ) ) t = max[1];
} else {
if( b > min[1] && ( trimMask & 4 ) ) b = min[1];
if( t < max[1] && ( trimMask & 8 ) ) t = max[1];
}
if( ortho )
projectionMatrix.makeOrtho( l, r, b, t, n, f );
else
projectionMatrix.makeFrustum( l, r, b, t, n, f );
#endif
}