A method for generating a treatment plan for therapy comprising obtaining image data representing a tissue, determining a therapy dose map comprising dose values for a plurality of dose points based on the image data, forming a desired dose value vector comprising the dose values for the plurality of dose points, determining a one or more potential therapy locations based on the image data, determining a therapy dose map equation for each of the plurality of dose points based on the one or more potential therapy locations, forming a matrix based on the therapy dose map equations for the each dose points, determining an inverse of the matrix and determining the treatment plan by multiplying the desired dose value vector by the inverse of the matrix.