Method getFrustumClipProj

Engine/source/scene/reflector.cpp:824–875

}

MatrixF PlaneReflector::getFrustumClipProj( MatrixF &modelview )
{
   static MatrixF rotMat(EulerF( static_cast<F32>(M_PI / 2.f), 0.0, 0.0));
   static MatrixF invRotMat(EulerF( -static_cast<F32>(M_PI / 2.f), 0.0, 0.0));


   MatrixF revModelview = modelview;
   revModelview = rotMat * revModelview;  // add rotation to modelview because it needs to be removed from projection

   // rotate clip plane into modelview space
   Point4F clipPlane;
   Point3F pnt = refplane * -(refplane.d + 0.0 );
   Point3F norm = refplane;

   revModelview.mulP( pnt );
   revModelview.mulV( norm );
   norm.normalize();

   clipPlane.set( norm.x, norm.y, norm.z, -mDot( pnt, norm ) );


   // Manipulate projection matrix
   //------------------------------------------------------------------------
   MatrixF proj = GFX->getProjectionMatrix();
   proj.mul( invRotMat );  // reverse rotation imposed by Torque
   proj.transpose();       // switch to row-major order

   // Calculate the clip-space corner point opposite the clipping plane
   // as (sgn(clipPlane.x), sgn(clipPlane.y), 1, 1) and
   // transform it into camera space by multiplying it
   // by the inverse of the projection matrix
   Vector4F   q;
   q.x = sgn(clipPlane.x) / proj(0,0);
   q.y = sgn(clipPlane.y) / proj(1,1);
   q.z = -1.0F;
   q.w = ( 1.0F - proj(2,2) ) / proj(3,2);

   F32 a = 1.0 / (clipPlane.x * q.x + clipPlane.y * q.y + clipPlane.z * q.z + clipPlane.w * q.w);

   Vector4F c = clipPlane * a;

   // CodeReview [ags 1/23/08] Come up with a better way to deal with this.
   if(GFX->getAdapterType() == OpenGL)
      c.z += 1.0f;

   // Replace the third column of the projection matrix
   proj.setColumn( 2, c );
   proj.transpose(); // convert back to column major order
   proj.mul( rotMat );  // restore Torque rotation

   return proj;
}