体绘制是一种三维空间中而非三维空间中的二维曲面上绘制三维数据的技术。体绘制和几何绘制并没有严格的界限。两种技术经常会有相似的结果，有时两者又可认为是一种技术。(Volume rendering is a technique for rendering three-dimensional data on two-dimensional surfaces in three-dimensional space rather than two-dimensional surfaces in three-dimensional space.)