Abstract: This paper proposes two visualization methods of multi-layer isosurface which extract from electromagnetism environment for the different requirements.Multi-layer Bogus Taxis，boosting up the borderline using Per-Pixel Shading，improves the performance of rendering but the quality is low.Improved Depth Peeling solves the problem of non-uniform depth distributing of multi-fragment through using Slicemap technology.The state-of-art of improved Depth Peeling gains great improvement for large scenes with high complexity.The algorithm gains a great balance between performance and quality，and is capable to capture up to multi-fragments in a single geometry pass with great speed improvement and faithful results.

Key words: Graphic Processing Unit（GPU）, multiple render target, depth peeling, bucket sort

摘要： 针对电磁环境三维体数据中提取出的多层等值面，根据交互绘制速率与绘制质量的不同要求，提出分层伪排序融合绘制方法和改进Depth Peeling融合绘制方法。前者实现了多层等值面的近似排序，采用逐像素着色增强边界轮廓，绘制速率快，适合需要快速绘制而质量要求不高的场合;后者通过引入Slicemap技术，解决了多层等值面片元分布不均匀的问题，并利用多遍绘制融合方法，提高了绘制复杂等值面的能力，从可视化效果看，提高了绘制质量，绘制效率也得到了保证。

关键词: 图形处理器, 多目标渲染目标缓存, 深度剥离, 桶排序