osg::Vec3d ViewingCore::findDeltaOnPanPlane(double ndcX1, double ndcY1, double ndcX2, double ndcY2)
{
// Get the view volume far plane value, and the distance from
// the near to far plane.
double zNear, zFar;
osg::Matrixd p = computeProjection();
if( getOrtho() ) {
double l, r, b, t;
p.getOrtho( l, r, b, t, zNear, zFar );
} else {
double fovy, aspect;
p.getPerspective( fovy, aspect, zNear, zFar );
}
const double distance = zFar - zNear;
// Create two points, both in NDC space, and lying on the far plane at the back
// of the view volume. One is the xy origin, the other with the passed xy parameters.
osg::Vec4d farPoint0 = osg::Vec4d( ndcX1, ndcY1, 1., 1. );
osg::Vec4d farPoint1 = osg::Vec4d( ndcX2, ndcY2, 1., 1. );
if( !getOrtho() ) {
// Not ortho, so w != 1.0. Multiply by the far plane distance.
// This yields values in clip coordinates.
farPoint0 *= zFar;
farPoint1 *= zFar;
}
// Get inverse view & proj matrices to back-transform the
// two clip coord far points into world space.
osg::Matrixd v = getMatrix();
p.invert( p );
osg::Vec4d wc0 = farPoint0 * p * v;
osg::Vec4d wc1 = farPoint1 * p * v;
// Intersect the two world coord points with the pan plane.
osg::Vec3d result0, result1;
osg::Vec3d p1( wc0.x(), wc0.y(), wc0.z() );
osg::Vec3d p0 = getOrtho() ? p1 - ( _viewDir * distance ) : getEyePosition();
intersectPlaneRay( result0, _panPlane, p0, p1 );
p1 = osg::Vec3d( wc1.x(), wc1.y(), wc1.z() );
p0 = getOrtho() ? p1 - ( _viewDir * distance ) : getEyePosition();
intersectPlaneRay( result1, _panPlane, p0, p1 );
// Subtract the two plane intersection points to get the delta world coord
// motion return
return result1 - result0;
}
void ViewingCore::pan( const double ndcX, const double ndcY )
{
// Get the view volume far plane value, and the distance from
// the near to far plane.
double zNear, zFar;
osg::Matrixd p;
getZNearZFarProj(zNear, zFar, p);
const double distance = zFar - zNear;
// Create two points, both in NDC space, and lying on the far plane at the back
// of the view volume. One is the xy origin, the other with the passed xy parameters.
osg::Vec4d farPoint0 = osg::Vec4d( 0., 0., 1., 1. );
osg::Vec4d farPoint1 = osg::Vec4d( ndcX, ndcY, 1., 1. );
if( !getOrtho() ) {
// Not ortho, so w != 1.0. Multiply by the far plane distance.
// This yields values in clip coordinates.
farPoint0 *= zFar;
farPoint1 *= zFar;
}
// Get inverse view & proj matrices to back-transform the
// two clip coord far points into world space.
osg::Matrixd v = getMatrix();
p.invert( p );
osg::Vec4d wc0 = farPoint0 * p * v;
osg::Vec4d wc1 = farPoint1 * p * v;
// Intersect the two world coord points with the pan plane.
osg::Vec3d result0, result1;
osg::Vec3d p1( wc0.x(), wc0.y(), wc0.z() );
osg::Vec3d p0 = getOrtho() ? p1 - ( _viewDir * distance ) : getEyePosition();
intersectPlaneRay( result0, _panPlane, p0, p1 );
p1 = osg::Vec3d( wc1.x(), wc1.y(), wc1.z() );
p0 = getOrtho() ? p1 - ( _viewDir * distance ) : getEyePosition();
intersectPlaneRay( result1, _panPlane, p0, p1 );
// Subtract the two plane intersection points to get the delta world coord
// motion and move the view center accordingly.
osg::Vec3d delta = result1 - result0;
osg::notify( osg::DEBUG_FP ) << " delta " << delta << std::endl;
_viewCenter -= delta;
}
bool calcDistToLine(const Ray3f &lineSegmentRay, const Ray3f &ray,
float32 &distQuad, float32 &rayParam, float32 &lineSegParam)
{
Vector3f distNormal = lineSegmentRay.direction.crossProduct(ray.direction);
if (distNormal*distNormal < EPSILON * EPSILON) return false;
Vector3f planeRayNormal = ray.direction.crossProduct(distNormal);
bool iFound = intersectPlaneRay(lineSegmentRay, planeRayNormal, ray.origin, lineSegParam);
if (!iFound || lineSegParam < 0 || lineSegParam > 1) {
return false;
}
Vector3f planeLineSegNormal = lineSegmentRay.direction.crossProduct(distNormal);
iFound = intersectPlaneRay(ray, planeLineSegNormal, lineSegmentRay.origin, rayParam);
if (iFound) {
Vector3f dist = lineSegmentRay.origin + lineSegmentRay.direction * lineSegParam
- (ray.origin + ray.direction * rayParam);
distQuad = dist*dist;
return true;
}
return false;
}
