OpenMW/apps/openmw/mwrender/rotatecontroller.cpp

#include "rotatecontroller.hpp"

#include <osg/MatrixTransform>

namespace MWRender
{

    RotateController::RotateController(osg::Node* relativeTo)
        : mEnabled(true)
        , mRelativeTo(relativeTo)
    {
    }

    void RotateController::setEnabled(bool enabled)
    {
        mEnabled = enabled;
    }

    void RotateController::setRotate(const osg::Quat& rotate)
    {
        mRotate = rotate;
    }

    void RotateController::setOffset(const osg::Vec3f& offset)
    {
        mOffset = offset;
    }

    void RotateController::operator()(osg::MatrixTransform* node, osg::NodeVisitor* nv)
    {
        if (!mEnabled)
        {
            traverse(node, nv);
            return;
        }
        osg::Matrix matrix = node->getMatrix();
        osg::Quat worldOrient = getWorldOrientation(node);
        osg::Quat worldOrientInverse = worldOrient.inverse();

        osg::Quat orient = worldOrient * mRotate * worldOrientInverse * matrix.getRotate();
        matrix.setRotate(orient);
        matrix.setTrans(matrix.getTrans() + worldOrientInverse * mOffset);

        node->setMatrix(matrix);

        traverse(node, nv);
    }

    osg::Quat RotateController::getWorldOrientation(osg::Node* node)
    {
        // this could be optimized later, we just need the world orientation, not the full matrix
        osg::NodePathList nodepaths = node->getParentalNodePaths(mRelativeTo);
        osg::Quat worldOrient;
        if (!nodepaths.empty())
        {
            osg::Matrixf worldMat = osg::computeLocalToWorld(nodepaths[0]);
            worldOrient = worldMat.getRotate();
        }
        return worldOrient;
    }

}