规则网格实时绘制关键技术研究
|
摘要
随着现代测绘及遥感技术的发展，获取的高程和影像数据正在以前所未有的速度增长，从数字城市到数字中国再到数字地球，地形数据也呈几何级数增长；与此同时，人类对虚拟场景中几何模型的逼真程度和绘制速度的需求也越来越大。以高程影像和曲面细化模板为代表的规则网格数据具有数据量大、空间布局规整以及需要实时显示等共同特点。
目前规则网格实时绘制仍面临诸多技术难点，如缺乏科学有效的多细节层次空间误差阈值设定、缺乏科学的量化精度依据来引导几何数据压缩、瓦块四叉树上视域可见性和细节层次(Level of Detail, LOD)选择计算效率不高、缺少高效灵活的多细节层次网格裂缝处理、曲面细化自适应度低、难以扩展到移动平台等关键问题，制约着数据规模、绘制质量及效率等方面的进一步扩展。
考虑LOD空间误差阈值缺乏合理性，在分块地形多误差条件下，以屏幕空间为参考来引导地形层次划分；分析地形处理和绘制过程中引入的误差因素，并以此为参数确定地形数据量计算函数，自适应地设定简化尺度和量化位数，生成最小化的地形压缩数据。
针对目前单层次瓦块调度图(Tile Load Map,TLM)存在的缺陷，提出多层次瓦块调度图来加速LOD选择和可见性判断。通过对基于外存地形LOD可视化高效架构特征的分析，基于TLM思想，将瓦块四叉树映射为二维纹理，用GPU完成地形块的视域裁剪和细节层次选择，解决CPU中海量地形地形块选择复杂度太大的问题，形成了多层次瓦块调度图算法；设计∏空间填充曲线重组Tile数据，改善数据访问局部性；设计资源池方式管理纹理对象，减少CPU-GPU带宽。
鉴于目前规则网格裂缝处理效率不高，提出多尺度规则网格裂缝参数化处理方法，利用曲线函数控制不同LOD过渡时的网格顶点布局，消除因细节层次过渡产生的T型连接，并扩展至消除多跨度LOD裂缝。
分析了二分细化自适应性低的原因，提出在GPU上实现裂缝处理的偶数曲面细化模式。通过在顶点着色器中引入顶点调控函数控制顶点偏移，解决边界裂缝问题；采用参数区域划分子区域的方法，解决函数坐标轴方向不一致引起的浮点误差问题；利用偶数细化层次递增关系，优化参数几何数据布局，达到层次间顶点和索引双重用。
给出适用于移动终端的自适应曲面细化管线。在偶数曲面细化模式基础上，设计适用于移动终端的自适应曲面细化管线，实现了几何模型在移动平台上的交互式渲染。
实验表明本文的研究工作有效提高了规则网格的绘制效率，相应研究成果已应用于相关863课题。
With the development of modern mapping and remote sensing technology, the size ofelevation and image data is growing at an unprecedented rate. From digital city to digitalChina, and then to digital earth, terrain data are growing exponentially. At the same time,the requirement of realism and rendering speed of the geometric model in the virtual sceneis also growing. The regular grid data, focusing on elevation images and surfacerefinement templates, represent common characteristics, such as the large amount of data,the spatial layout of regular, and the need for real-time rendering.
The real-time rendering of regular grid faces some technical difficulties, such as thelack of scientific and effective space error threshold setting for level of details(LOD), thelack of scientific quantization precision to guide the geometric data compression, the lowperformance of view visibility and LOD selection computing on Tiled Quadtree, the lackof efficient and flexible crack treatment for LOD, the low adaptivity of surface refinement,the difficulty to be extended for the mobile platform and so on. These restrict the scalableof data size, render quality and efficiency.
Considering the lack of a reasonable space error threshold for LOD, the world-spaceerror bound was set for each level of Tiled Quadtree by referencing screen space Firstly.Secondly, we gave the optimization of vertex simplification and quantization bits,considering all kinds of errors introduced by terrain processing and rendering, andcombining the current function computing the data size of tile compressed mesh.
Considering the lack of Tile Load Map, we proposed Multilevel Tile Load Mapalgorithm. We analyzed efficient architecture features of massive terrain LODvisualization, and found that CPU could hardly select tiles from mass terrain effectivelywithin the real-time limit. This restricts the expansion of terrain’s size. Multilevel TileLoad Map (MTLM) algorithm was proposed for tile selection to extend TLM. It uses2dtexture for saving Tiled Quadtree (TQT), and executes tile view-frustum culling andlevel-of-detail selection by GPU acceleration. The scalability constraint was avoided bydealing tile selection with high-performance image processing in TLM. In addition, optimization was presented at tile data organization and resource management.
In the light of the current regular grid crack treatment efficiency, we proposedparameterization method for multi-scale regular-grid model repairing cracks. Functioncurve fitting was utilized to change the mesh layout and eliminate T-junctions caused byvarious LODs transition. Moreover, the parameterization cracks-repairing methodsupports multi-span LOD using curve function family excellently.
In analysing the low adaptivity of semi-uniform adaptive patch tessellation, weproposed GPU-based crack-avoiding adaptive even tessellation. Based on theparameterization method for multi-scale regular-grid model repairing cracks, in order toimprove semi-uniform adaptive patch tessellation, even tessellation was proposed usingvertex fitting function to increase tessellation level styles. Vertex was shifted bycontrolling function on vertex shader to eliminate the boundary cracks. In addition,parameter region was divided to avoid floating point precision issue caused by directioninconsistency of function coordinate axes. Then, parametric mesh layouts were optimized,and both vertex and index could be reused between different tessellation levels.
Lastly, we gave an adaptive refinement pipeline for mobile terminals.Based onadaptive even tessellation, we proposed an adaptive mesh refinement pipeline based onPN triangles. The geometric model implemented interactive rendering on the mobileplatform.
The experiments show that our researches effectively improve the efficiency ofregular-grid real-time rendering, and the above research results have been applied torelated863projects.
目前规则网格实时绘制仍面临诸多技术难点，如缺乏科学有效的多细节层次空间误差阈值设定、缺乏科学的量化精度依据来引导几何数据压缩、瓦块四叉树上视域可见性和细节层次(Level of Detail, LOD)选择计算效率不高、缺少高效灵活的多细节层次网格裂缝处理、曲面细化自适应度低、难以扩展到移动平台等关键问题，制约着数据规模、绘制质量及效率等方面的进一步扩展。
考虑LOD空间误差阈值缺乏合理性，在分块地形多误差条件下，以屏幕空间为参考来引导地形层次划分；分析地形处理和绘制过程中引入的误差因素，并以此为参数确定地形数据量计算函数，自适应地设定简化尺度和量化位数，生成最小化的地形压缩数据。
针对目前单层次瓦块调度图(Tile Load Map,TLM)存在的缺陷，提出多层次瓦块调度图来加速LOD选择和可见性判断。通过对基于外存地形LOD可视化高效架构特征的分析，基于TLM思想，将瓦块四叉树映射为二维纹理，用GPU完成地形块的视域裁剪和细节层次选择，解决CPU中海量地形地形块选择复杂度太大的问题，形成了多层次瓦块调度图算法；设计∏空间填充曲线重组Tile数据，改善数据访问局部性；设计资源池方式管理纹理对象，减少CPU-GPU带宽。
鉴于目前规则网格裂缝处理效率不高，提出多尺度规则网格裂缝参数化处理方法，利用曲线函数控制不同LOD过渡时的网格顶点布局，消除因细节层次过渡产生的T型连接，并扩展至消除多跨度LOD裂缝。
分析了二分细化自适应性低的原因，提出在GPU上实现裂缝处理的偶数曲面细化模式。通过在顶点着色器中引入顶点调控函数控制顶点偏移，解决边界裂缝问题；采用参数区域划分子区域的方法，解决函数坐标轴方向不一致引起的浮点误差问题；利用偶数细化层次递增关系，优化参数几何数据布局，达到层次间顶点和索引双重用。
给出适用于移动终端的自适应曲面细化管线。在偶数曲面细化模式基础上，设计适用于移动终端的自适应曲面细化管线，实现了几何模型在移动平台上的交互式渲染。
实验表明本文的研究工作有效提高了规则网格的绘制效率，相应研究成果已应用于相关863课题。
With the development of modern mapping and remote sensing technology, the size ofelevation and image data is growing at an unprecedented rate. From digital city to digitalChina, and then to digital earth, terrain data are growing exponentially. At the same time,the requirement of realism and rendering speed of the geometric model in the virtual sceneis also growing. The regular grid data, focusing on elevation images and surfacerefinement templates, represent common characteristics, such as the large amount of data,the spatial layout of regular, and the need for real-time rendering.
The real-time rendering of regular grid faces some technical difficulties, such as thelack of scientific and effective space error threshold setting for level of details(LOD), thelack of scientific quantization precision to guide the geometric data compression, the lowperformance of view visibility and LOD selection computing on Tiled Quadtree, the lackof efficient and flexible crack treatment for LOD, the low adaptivity of surface refinement,the difficulty to be extended for the mobile platform and so on. These restrict the scalableof data size, render quality and efficiency.
Considering the lack of a reasonable space error threshold for LOD, the world-spaceerror bound was set for each level of Tiled Quadtree by referencing screen space Firstly.Secondly, we gave the optimization of vertex simplification and quantization bits,considering all kinds of errors introduced by terrain processing and rendering, andcombining the current function computing the data size of tile compressed mesh.
Considering the lack of Tile Load Map, we proposed Multilevel Tile Load Mapalgorithm. We analyzed efficient architecture features of massive terrain LODvisualization, and found that CPU could hardly select tiles from mass terrain effectivelywithin the real-time limit. This restricts the expansion of terrain’s size. Multilevel TileLoad Map (MTLM) algorithm was proposed for tile selection to extend TLM. It uses2dtexture for saving Tiled Quadtree (TQT), and executes tile view-frustum culling andlevel-of-detail selection by GPU acceleration. The scalability constraint was avoided bydealing tile selection with high-performance image processing in TLM. In addition, optimization was presented at tile data organization and resource management.
In the light of the current regular grid crack treatment efficiency, we proposedparameterization method for multi-scale regular-grid model repairing cracks. Functioncurve fitting was utilized to change the mesh layout and eliminate T-junctions caused byvarious LODs transition. Moreover, the parameterization cracks-repairing methodsupports multi-span LOD using curve function family excellently.
In analysing the low adaptivity of semi-uniform adaptive patch tessellation, weproposed GPU-based crack-avoiding adaptive even tessellation. Based on theparameterization method for multi-scale regular-grid model repairing cracks, in order toimprove semi-uniform adaptive patch tessellation, even tessellation was proposed usingvertex fitting function to increase tessellation level styles. Vertex was shifted bycontrolling function on vertex shader to eliminate the boundary cracks. In addition,parameter region was divided to avoid floating point precision issue caused by directioninconsistency of function coordinate axes. Then, parametric mesh layouts were optimized,and both vertex and index could be reused between different tessellation levels.
Lastly, we gave an adaptive refinement pipeline for mobile terminals.Based onadaptive even tessellation, we proposed an adaptive mesh refinement pipeline based onPN triangles. The geometric model implemented interactive rendering on the mobileplatform.
The experiments show that our researches effectively improve the efficiency ofregular-grid real-time rendering, and the above research results have been applied torelated863projects.
引文
[1] Cohen J, Olano M, Manocha D. Appearance-Preserving Simplification[C]//Proceedings of the25th Annual Conference on Computer Graphics and Interactive Techniques. New York:ACM.1998:115-122.
[2]赵健.虚拟场景的视点质量评价与绘制优化问题研究[D].长沙:国防科学技术大学,2010:15-16.
[3]张书,褚艳利,赵开勇,等. GPU高性能运算之CUDA [M].北京:中国水利水电出版社,2009:1-11.
[4] Hillesland. OpenGL: the DirectX Perspective[R]. SIGGRAPH Asia2012Courses. New York:ACM.2012:1-49.
[5]张慧杰,孙吉贵,吕英华,等.一种新的基于发散度函数的地形模型简化方法[J].计算机学报,2009,32(5):962-973.
[6] Lindstrom P, Koller D, Hodges L F, et al. Level-of-Detail Management for Real-Time Renderingof Phototextured Terrain[R]. Atlanta: Georgia Institute of Technology.1995:1-16.
[7] Pajarola R. Large Scale Terrain Visualization Using the Restricted Quadtree Triangulation [C]//Proceedings of the conference on Visualization '98. North Carolina: IEEE Computer SocietyPress.1998:19-26.
[8] Velho L. Using Semi-Regular4-8Meshes for Subdivision Surfaces [J]. Journal of Graphics Tools,2000,5(3):35-47.
[9] Velho L, Gomes J. Variable Resolution4-k Meshes: Concepts and Applications [J]. ComputerGraphics Forum,2000,19(4):195-212.
[10] Yalcin M A, Weiss K, Floriani L D. GPU Algorithms for Diamond-Based Multiresolution TerrainProcessing [C]//Proceedings of the11th Eurographics conference on Parallel Graphics andVisualization. Swutzerkabd: Aire-la-Ville.2011:121-130.
[11] Duchaineau M, Wolinsky M, Sigeti D E, et al. Roaming Terrain: Real-time Optimally AdaptingMeshes [C]//Proceedings of the8th Conference on Visualization '97. Arizona: IEEE ComputerSociety Press.1997:81-88.
[12] Lindstrom P, Pascucci V. Visualization of Large Terrains Made Easy[C]. Proceedings of theConference on Visualization '01. California: IEEE Computer Society.2001:363-371.
[13] Lindstrom P, Pascucci V. Terrain Simplification Simplified: A General Framework forView-Dependent Out-of-core Visualization[J]. IEEE Transactions on Visualization and ComputerGraphics,2002,8(3):239-254.
[14]周海东,廖学军,汪荣峰.基于海量空间数据的实时地形视景仿真算法研究[J].系统仿真学报,2005,17(11):2606-2609.
[15]蔡兴泉,李凤霞,战守义.复杂战场环境中基于规则网格的动态地形得研究[J].系统仿真学报,2005,17(3):650-652.
[16]刘少华,张茂军,张恒.大规模地形场景实时漫游系统的构建[J].计算机仿真,2005,22(6):178-181.
[17] Gerstner T. Top–Down View–Dependent Terrain Triangulation Using the Octagon Metric [R]Bonn: Institute of Applied Mathematics.2003:1-11.
[18]陆艳青,华炜,鲍虎军,等.大规模地形数据的自适应动态装载[C]//第四届中国计算机图形大会.北京:清华大学出版社.2002:116-124.
[19]陆艳青.海量地形数据实时绘制的技术研究[D].杭州:浙江大学,2003:36-39.
[20]唐勇,郭栋梁,吕梦雅.视点相关的大规模地形内外存调度算法的研究[J].系统仿真学报,2009,21(8):2424-2427.
[21] Losasso F, Hoppe H. Geometry Clipmaps: Terrain Rendering Using Nested Regular Grids[J].ACM Transaction on Graphics,2004,23(3):769-776.
[22] Williams L. Pyramidal Parametrics[J]//ACM SIGGRAPH Computer Graphics,1983,17(3):1-11.
[23] Boer W H D. Fast Terrain Rendering Using Geometrical MipMapping[OL].(2000-12-19)[2013-02-04].http://www.flipcode.com/archives/article_geomipmaps.pdf.
[24]张浩.不对称的Geometry Clipmap算法[D].武汉:华中科技大学,2005:17-34.
[25]康宁.基于GPU的全球地形实时绘制技术[D].郑州:解放军信息工程大学,2007:38-39.
[26] Clasen M, Hege H-C. Terrain Rendering Using Spherical Clipmaps[C]//Joint Eurographics-IEEE VGTC Symposium on Visualization-VisSym. Lisbon: Eurographics Association.2006:91-98.
[27] Clasen M, Hege H-C. Clipmap-Based Terrain Data Synthesis[C]//Simulation and Visualisierung2007.New York: ACM.2007:385-398.
[28]于卓,梁晓辉,马上,等.一种支持大规模多种精度地形的实时绘制算法[J].计算机研究与发展,2010,47(6):988-996.
[29] Pajarola R, Gobbetti E. Survey of Semi-Regular Multiresolution Models for Interactive TerrainRendering[J]. Visual Computer,2007,23(8):583-605.
[30] Gobbetti E, Marton F, Cignoni P, et al. C-BDAM-Compressed Batched Dynamic AdaptiveMeshes for Terrain Rendering[J]. Computer Graphics Forum,2006,25(3):333-342.
[31] Cignoni P, Ganovelli F, Gobbetti E, et al. BDAM-Batched Dynamic Adaptive Meshes for HighPerformance Terrain Visualization[J]. Computer Graphics Forum,2003,22(3):505-514.
[32] Lindstrom P, Cohen J D. On-the-fly Decompression and Rendering of MultiresolutionTerrain[C]//Proceedings of the2010ACM SIGGRAPH Symposium on Interactive3D Graphicsand Games. Washington: ACM.2010:65-73.
[33] Bosch J, Goswami P, Pajarola R. Raster: Simple and Efficient Terrain Rendering on theGPU[C]//Proceedings of EUROGRAPHICS2009. Aire-la-Ville: Eurographics Association.2009:35-42.
[34] Goswami P, Makhinya M, Bosch J, et al. Scalable Parallel Out-of-core TerrainRendering[C]//Proceedings of the10th Eurographics Conference on Parallel Graphics andVisualization. Ping: Eurographics Association.2010:63-71.
[35] Ulrich T. Rendering Massive Terrains Using Chunked Level of Detail Control[R]. Course Notesof ACM SIGGRAPH. San Antonio: SIGGRAPH,2002,35.
[36]卓亚芬. ChunkedLOD—海量地形的实时绘制系统[D].杭州:浙江大学,2004:35-39.
[37]李胜,冀俊峰,刘学慧,等.超大规模地形场景的高性能漫游[J].软件学报,2006,17(3):535-545.
[38] Dick C, Schneider J, Westermann R. Efficient Geometry Compression for GPU-based Decodingin Realtime Terrain Rendering[J]. Computer Graphics Forum,2009,28(1):67-83.
[39] Dick C, Kr Ger J, Westermann R. GPU Ray-casting for Scalable TerrainRendering[C]//Proceedings of Eurographics. Genve: EUROGRAPHICS Associations,2009,28:43-50.
[40] Dick C, Kruger J, Westermann R. GPU-Aware Hybrid Terrain Rendering[J]. InternationalJournal of Computer Information Systems and Industrial Management Applications,2011,3:820-827.
[41] Ammann L, Gnevaux O, Dischler J-M. Hybrid Rendering of Dynamic Heightfields UsingRay-Casting and Mesh Rasterization[C]//Proceedings of Graphics Interface2010.Ottawa:Canadian Information Processing Society.2010:161-168.
[42]李白云,赵春霞. GPU实时构建四叉树的快速地形渲染算法[J].计算机辅助设计与图形学学报,2010,22(12):2259-2264.
[43]张豫南,王冬,夏乙,等.瓦片块四叉树动态地形细节层次算法[J].兵工学报,2011,32(11):1411-1415.
[44] Yusov E, Shevtsov M. High-Performance Terrain Rendering Using Hardware Tessellation[J].Journal of WSCG,2011,19(1):85-92.
[45] Asirvatham A, Hoppe H. Terrain Rendering Using GPU-based Geometry Clipmaps[M]. GPUGems, Boston: Addison-Wesley,2005:27-45.
[46] Dirk Feldmann K H. GPU Based Single-Pass Ray Casting of Large Heighfields UsingClipmaps[OL].[2013-02-04] http://viscg.uni-muenster.de/publications/2012/FH12/.
[47] Schneider J, Westermann R U. GPU-friendly High-quality Terrain Rendering[J]. Journal ofWSCG.2006,14(3):49-56.
[48] Wahl R, Massing M, Degener P, et al. Scalable Compression and Rendering of Textured TerrainData [J]. Journal of WSCG.2004,12(3):521-528.
[49] Purnomo B, Bilodeau J, Cohen J D, et al. Hardware-Compatible Vertex Compression UsingQuantization and Simplification[C]//Proceedings of the ACM SIGGRAPH/EUROGRAPHICSConference on Graphics hardware. Los Angeles: ACM.2005:53-61.
[50] Yoon S-E, Lindstrom P. Mesh Layouts for Block-Based Caches[J]. IEEE Transactions onVisualization and Computer Graphics.2006,12(5):1213-1220.
[51] Yoon S-E, Lindstrom P. Random-Accessible Compressed Triangle Meshes[J]. IEEE Transactionson Visualization and Computer Graphics.2007,13(6):1536-1543.
[52] Livny Y, Kogan Z, El-Sana J. Seamless Patches for GPU-Based Terrain Rendering[J]. The VisualComputer,2009,25(3):197-208.
[53] Livny Y, Sokolovsky N, Grinshpoun T, et al. A GPU Persistent Grid Mapping for TerrainRendering[J]. The Visual Computer,2008,24(2):139-153.
[54] Roth S D. Ray Casting for Modeling Solids[J]. Computer Graphics and Image Processing,1982,18(2):109-144.
[55] Johanson C. Real-Time Water Rendering-Introducing the Projected Grid Concept [D]. Lund:Lund University,2004.
[56] Tevs A, Ihrke I, Seidel H-P. Maximum Mipmaps for Fast, Accurate, and Scalable DynamicHeight Field Rendering[C]//Proceedings of the2008Symposium on Interactive3D GraphicsAnd Games. Redwood: ACM.2008:183-190.
[57] Hubert Nguyen. GPU精粹3[M].杨柏林,陈根浪,王聪译.北京:清华大学出版社,2007:409-428.
[58]陈静,龚健雅,朱欣焰,等.分布式虚拟地形场景仿真研究[J].系统仿真学报,2007,19(5):1057-1060,1081.
[59]徐正全,高路,李忠民,等.基于非结构化P2P网络的地形数据存储系统[J].武汉大学学报(信息科学版),2010,35(1):122-125.
[60]王永君,龚健雅.用于大范围虚拟地形环境的动态场景管理方法[J].测绘学院学报,2003,20(3):231-234.
[61]朱庆,赵杰,钟正,等.基于规则格网DEM的地形特征提取算法[J].测绘学报,2004,33(1):77-82.
[62]许妙忠.大规模地形实时绘制的算法研究[J].武汉大学学报(信息科学版),2005,30(5):392-395.
[63]喻占武,郑胜,李忠民.一种混合式P2P下的大规模地形数据传输机制[J].测绘学报,2008,37(2):243-249.
[64]潘少明,喻占武,李锐.基于主动缓存的P2P海量地形漫游瓦片调度算法[J].测绘学报,2009,38(3):236-241,249.
[65]赵友兵,石教英,周骥,等.一种大规模地形的快速漫游算法[J].计算机辅助设计与图形学学报,2002,14(7):624-628.
[66]肖俊,庄越挺,吴飞.基于细节层次与最小生成树的三维地形识别与检索[J].软件学报,2003,14(11):1955-1963.
[67]施松新,叶修梓,张三元,等.基于分块的大规模地形实时渲染方法[J].浙江大学学报(工学版),2007,41(12):2002-2006，2016.
[68]施松新,张引,叶修梓,等.大规模地形场景流式渐进传输[J].浙江大学学报(工学版),2008,42(11):1862-1867.
[69]夏杰,陈奇.基于静态LOD的海量地形绘制中的接缝算法[J].计算机工程与设计,2010,31(22):4847-4850.
[70] Moreton H. Watertight Tessellation Using Forward Differencing[C]//Proceedings of the ACMSIGGRAPH/EUROGRAPHICS Workshop on Graphics Hardware. Los Angeles: ACM.2001:25-32.
[71] Munkberg J, Hasselgren J, Akenine-Moller T. Non-Uniform FractionalTessellation[C]//Proceedings of the23rd ACM SIGGRAPH/EUROGRAPHICS Symposium onGraphics hardware. Switzerland: Eurographics Association Aire-la-Ville.2008:41-45.
[72] Schwarz M, Stamminger M. Fast GPU-based Adaptive Tessellation with CUDA[J]. ComputGraph Forum,2009,28(2):365-374.
[73] Bailey M, Cunningham S. GPU Shaders for OpenGL4.0[M]. SIGGRAPH Asia2011Courses.Hong Kong: ACM.2011:1-89.
[74] Boubekeur T, Schlick C. Generic Mesh Refinement on GPU[C]//Proceedings of the ACMSIGGRAPH/EUROGRAPHICS Conference on Graphics hardware. Los Angeles:ACM.2005:99-104.
[75] Boubekeur T, Schlick C. A Flexible Kernel for Adaptive Mesh Refinement on GPU[J]. ComputerGraphics Forum,2008,27(1):102-114.
[76] Lorenz H, Dollner J. Dynamic mesh refinement on GPU using geometry shaders[J]. Journal ofWSCG,2008,16(1):97–104.
[77] Dyken C, Reimers M, Seland J. Real-Time GPU Silhouette Refinement Using AdaptivelyBlended Bézier Patches[J]. Computer Graphics Forum.2008,27(1):1-12.
[78] Dyken C, Reimers M, Seland J. Semi-Uniform Adaptive Patch Tessellation[J]. ComputerGraphics Forum,2009,28(8):2255-2263.
[79] Amresh A, Funfzig C. Semi-Uniform,2-Different Tessellation of Triangular ParametricSurfaces[C]//Proceedings of the6th International Conference on Advances in Visual Computing-Volume Part I. Heidelberg: Springer-Verlag Berlin.2010:54-63.
[80]王旭,阳新,王志铭.在GPU上实现地形渲染的自适应算法[J].计算机辅助设计与图形学学报,2010,22(10):1741-1750.
[81] Vlachos A, Peters J, Boyd C, et al. Curved PN triangles[C]//Proceedings of the2001Symposiumon Interactive3D Graphics. New York:ACM.2001:159-66.
[82] Yeo Y I, Ni T, Myles A, et al. Parallel Smoothing of Quad Meshes[J]. The Visual Computer,Springer-Verlag New York,2009,25(8):757-769.
[83] Boubekeur T, Alexa M. Phong Tessellation[J]. ACM Transactions on Graphics,2008,27(5):1-5.
[84]温佩芝,吴晓军,吴成柯.自适应细分曲面算法及在快速成型数据处理中的应用[J].计算机集成制造系统,2007,13(3):608-614.
[85]李胜,黄鑫,汪国平.基于GPU的视点相关自适应细分[J].计算机辅助设计与图形学学报,2007,19(4):409-414.
[86]张湘玉.基于细分的曲线曲面变形技术研究[D].南京:南京航空航天大学,2010:60-66.
[87] Hollander, M. Boubekeur, T. Synthesizing Subdivision Meshes using Real Time Tessellation[C]//Proceedings of the201018th Pacific Conference on Computer Graphics and Applications. LosAlamitos: IEEE Computer Society Press,2010:46-53.
[88]唐敏,童若锋,董金祥.基于GPU的曲面自适应细分[J].浙江大学学报(工学版),2008,42(7):1145-1149,1217.
[89] Loop C, Schaefer S, Ni T, et al. Approximating Subdivision Surfaces with Gregory Patches forHardware Tessellation[J]. ACM Transactions on Graphics,2009,28(5):1-9.
[90] Ni T. Efficient Substitutes for Subdivision Surfaces in Feature-Quality Games[M]. ACMSIGGRAPH ASIA2010Courses. Seoul:ACM.2010:1-77.
[91] Tatarinov A. Reyes Using DirectX11[M]. ACM SIGGRAPH2010Talks. Los Angeles:ACM.2010:1-10.
[92] Gobbetti E, Marton F, Rodriguez M B, et al. Adaptive Quad Patches: an Adaptive RegularStructure for Web Distribution and Adaptive Rendering of3D Models[C]//Proceedings of the17th International Conference on3D Web Technology. Los Angeles:ACM.2012:9-16.
[93] Fisher M, Fatahalian K, Boulos S, et al. DiagSplit: Parallel, Crack-Free, Adaptive Tessellationfor Micropolygon Rendering[J]. ACM Transactions on Graphics,2009,28(5):1-10.
[94] Niebner M, Loop C, Meyer M, et al. Feature-Adaptive GPU Rendering of Catmull-ClarkSubdivision Surfaces[J]. ACM Transactions on Graphics,2012,31(1):1-11.
[95] Schafer H, Prus M, Meyer Q, et al. Multiresolution Attributes for TessellatedMeshes[C]//Proceedings of the ACM SIGGRAPH Symposium on Interactive3D Graphics andGames. Costa Mesa: ACM.2012:175-82.
[96] Cook R L. Shade Trees[J]. SIGGRAPH Computer Graphics,1984,18(3):223-231.
[97]宋滢.非均质半透明材质的绘制及编辑算法研究[D].杭州:浙江大学,2009:18-20.
[98] Wang L, Wang X, Tong X, et al. View-Dependent Displacement Mapping[J]. ACM Transactionson Graphics,2003,22(3):334-339.
[99] Livny Y, Bauman G, El-Sana J. Displacement Patches for View-Dependent Rendering[J]. TheVisual Computer,2011,28(3):247-263.
[100] Wang X, Tong X, Lin S, et al. Generalized Displacement Maps[C]//Proceedings of the FifteenthEurographics Conference on Rendering Techniques. Ping: Eurographics Association.2004:227-233.
[101] Gu X, Gortler S J, Hoppe H. Geometry Images[J]. ACM Transactions on Graphics,2002,21(3):355-361.
[102] Losasso F, Hoppe H, Schaefer S, et al. Smooth Geometry Images[C]//Proceedings of the2003Eurographics/ACM SIGGRAPH Symposium on Geometry processing. Aachen: EurographicsAssociation.2003:138-145.
[103] Praun E, Hoppe H. Spherical Parametrization and Remeshing[J]. ACM Transactions on Graphics,2003,22(3):340-349.
[104] Sander P V, Wood Z J, Gortler S J, et al. Multi-Chart Geometry Images[C]//Proceedings of the2003Eurographics/ACM SIGGRAPH Symposium on Geometry processing. Aachen:Eurographics Association.2003:146-155.
[105] Carr N A, Hoberock J, Crane K, et al. Rectangular Multi-Chart GeometryImages[C]//Proceedings of the Fourth Eurographics Symposium on Geometry Processing.Cagliari: Eurographics Association.2006:181-190.
[106] Yao C Y, Lee T Y. Adaptive Geometry Image[J]. IEEE Transactions on Visualization andComputer Graphics,2008,14(4):948-960.
[107] Feng W W, Kim B U, Yu Y, et al. Feature-Preserving Triangular Geometry Images forLevel-Of-Detail Representation of Static And Skinned Meshes[J]. ACM Transactions onGraphics,2010,29(2):1-13.
[108] Wagner D. Terrain Geomorphing in the Vertex Shader [M]. Plano: Wordware Publishing.2004:1-12.
[109] Kooima R, Leigh J, Johnson A, et al. Planetary-Scale Terrain Composition[J]. IEEE Transactionson Visualization and Computer Graphics,2009,15(5):719-733.
[110] Roberts D A K M, Hardy A. Level of Detail for Terrain Geometry Images[C]//Proceedings of the5th International Conference on Computer Graphics, Virtual Reality, Visualisation andInteraction in Africa. Grahamstown: ACM.2007:25-30.
[111] Niski K, Purnomo B, Cohen J. Multi-Grained Level of Detail Using a Hierarchical SeamlessTexture Atlas[C]//Proceedings of the2007Symposium on Interactive3D Graphics and Games.Seattle: ACM.2007:153-60.
[112] Strugar F. Continuous Distance-Dependent Level of Detail for Rendering Heightmaps[J]. Journalof Graphics, GPU, and Game Tools,2010,14(4):57-74.
[113] Amara Y, Meunier S, Marsault X. A GPU Framework for the Visualization and on-the-FlyAmplification of Real Terrains[C]//Proceedings of the3rd International Conference on Advancesin Visual Computing. Lake Tahoe: Springer-Verlag.2007,1:586-597.
[114] Amara Y, Marsault X. A GPU Tile-Load-Map Architecture for Terrain Rendering: Theory andApplications[J]. The Visual Computer,2009,25(8):805-824.
[115]张燕燕,黄其涛,韩俊伟.基于提升小波的大地形累进压缩及实时渲染[J].计算机辅助设计与图形学学报,2010,22(8):1352-1359.
[116]刘迎,刘学慧,吴恩华.基于可变模版的三角网格拓扑压缩[J].软件学报,2008,19(4):1016-1025.
[117] Isenburg M, Lindstrom P, Snoeyink J. Streaming Compression of TriangleMeshes[C]//Proceedings of the Third Eurographics Symposium on Geometry Processing. Vienna:Eurographics Association.2005:111-120.
[118] Griebel M, Zumbusch G. Parallel Multigrid in an Adaptive PDE Solver Based on Hashing andSpace-Filling Curves[J]. Parallel Computing,1999,25(7):827-43.
[119] Laurent B, Jelena K, Martin V. Quadtrees for Embedded Surface Visualization: Constraints andEfficient Data Structures[J]. International Conference on Image Processing,1999,8(2):487-491.
[120]马建平,罗笑南,陈渤,等.面向移动终端的三角网格逆细分压缩算法[J].软件学报,2009,20(9):2607-2615.
[121] Gouraud H. Continuous Shading of Curved Surfaces[J]. IEEE Transactions on Visualization andComputer Graphics,1971,20(6):623-629.
[122] Phong B T. Illumination for Computer Generated Pictures[J]. Communications of the ACM,1975,18(6):311-317.
[123]吴亚峰. Android3D游戏开发技术宝典--OpenGL ES2.0[M].北京:人民邮电出版社,
2012:94-97.
[2]赵健.虚拟场景的视点质量评价与绘制优化问题研究[D].长沙:国防科学技术大学,2010:15-16.
[3]张书,褚艳利,赵开勇,等. GPU高性能运算之CUDA [M].北京:中国水利水电出版社,2009:1-11.
[4] Hillesland. OpenGL: the DirectX Perspective[R]. SIGGRAPH Asia2012Courses. New York:ACM.2012:1-49.
[5]张慧杰,孙吉贵,吕英华,等.一种新的基于发散度函数的地形模型简化方法[J].计算机学报,2009,32(5):962-973.
[6] Lindstrom P, Koller D, Hodges L F, et al. Level-of-Detail Management for Real-Time Renderingof Phototextured Terrain[R]. Atlanta: Georgia Institute of Technology.1995:1-16.
[7] Pajarola R. Large Scale Terrain Visualization Using the Restricted Quadtree Triangulation [C]//Proceedings of the conference on Visualization '98. North Carolina: IEEE Computer SocietyPress.1998:19-26.
[8] Velho L. Using Semi-Regular4-8Meshes for Subdivision Surfaces [J]. Journal of Graphics Tools,2000,5(3):35-47.
[9] Velho L, Gomes J. Variable Resolution4-k Meshes: Concepts and Applications [J]. ComputerGraphics Forum,2000,19(4):195-212.
[10] Yalcin M A, Weiss K, Floriani L D. GPU Algorithms for Diamond-Based Multiresolution TerrainProcessing [C]//Proceedings of the11th Eurographics conference on Parallel Graphics andVisualization. Swutzerkabd: Aire-la-Ville.2011:121-130.
[11] Duchaineau M, Wolinsky M, Sigeti D E, et al. Roaming Terrain: Real-time Optimally AdaptingMeshes [C]//Proceedings of the8th Conference on Visualization '97. Arizona: IEEE ComputerSociety Press.1997:81-88.
[12] Lindstrom P, Pascucci V. Visualization of Large Terrains Made Easy[C]. Proceedings of theConference on Visualization '01. California: IEEE Computer Society.2001:363-371.
[13] Lindstrom P, Pascucci V. Terrain Simplification Simplified: A General Framework forView-Dependent Out-of-core Visualization[J]. IEEE Transactions on Visualization and ComputerGraphics,2002,8(3):239-254.
[14]周海东,廖学军,汪荣峰.基于海量空间数据的实时地形视景仿真算法研究[J].系统仿真学报,2005,17(11):2606-2609.
[15]蔡兴泉,李凤霞,战守义.复杂战场环境中基于规则网格的动态地形得研究[J].系统仿真学报,2005,17(3):650-652.
[16]刘少华,张茂军,张恒.大规模地形场景实时漫游系统的构建[J].计算机仿真,2005,22(6):178-181.
[17] Gerstner T. Top–Down View–Dependent Terrain Triangulation Using the Octagon Metric [R]Bonn: Institute of Applied Mathematics.2003:1-11.
[18]陆艳青,华炜,鲍虎军,等.大规模地形数据的自适应动态装载[C]//第四届中国计算机图形大会.北京:清华大学出版社.2002:116-124.
[19]陆艳青.海量地形数据实时绘制的技术研究[D].杭州:浙江大学,2003:36-39.
[20]唐勇,郭栋梁,吕梦雅.视点相关的大规模地形内外存调度算法的研究[J].系统仿真学报,2009,21(8):2424-2427.
[21] Losasso F, Hoppe H. Geometry Clipmaps: Terrain Rendering Using Nested Regular Grids[J].ACM Transaction on Graphics,2004,23(3):769-776.
[22] Williams L. Pyramidal Parametrics[J]//ACM SIGGRAPH Computer Graphics,1983,17(3):1-11.
[23] Boer W H D. Fast Terrain Rendering Using Geometrical MipMapping[OL].(2000-12-19)[2013-02-04].http://www.flipcode.com/archives/article_geomipmaps.pdf.
[24]张浩.不对称的Geometry Clipmap算法[D].武汉:华中科技大学,2005:17-34.
[25]康宁.基于GPU的全球地形实时绘制技术[D].郑州:解放军信息工程大学,2007:38-39.
[26] Clasen M, Hege H-C. Terrain Rendering Using Spherical Clipmaps[C]//Joint Eurographics-IEEE VGTC Symposium on Visualization-VisSym. Lisbon: Eurographics Association.2006:91-98.
[27] Clasen M, Hege H-C. Clipmap-Based Terrain Data Synthesis[C]//Simulation and Visualisierung2007.New York: ACM.2007:385-398.
[28]于卓,梁晓辉,马上,等.一种支持大规模多种精度地形的实时绘制算法[J].计算机研究与发展,2010,47(6):988-996.
[29] Pajarola R, Gobbetti E. Survey of Semi-Regular Multiresolution Models for Interactive TerrainRendering[J]. Visual Computer,2007,23(8):583-605.
[30] Gobbetti E, Marton F, Cignoni P, et al. C-BDAM-Compressed Batched Dynamic AdaptiveMeshes for Terrain Rendering[J]. Computer Graphics Forum,2006,25(3):333-342.
[31] Cignoni P, Ganovelli F, Gobbetti E, et al. BDAM-Batched Dynamic Adaptive Meshes for HighPerformance Terrain Visualization[J]. Computer Graphics Forum,2003,22(3):505-514.
[32] Lindstrom P, Cohen J D. On-the-fly Decompression and Rendering of MultiresolutionTerrain[C]//Proceedings of the2010ACM SIGGRAPH Symposium on Interactive3D Graphicsand Games. Washington: ACM.2010:65-73.
[33] Bosch J, Goswami P, Pajarola R. Raster: Simple and Efficient Terrain Rendering on theGPU[C]//Proceedings of EUROGRAPHICS2009. Aire-la-Ville: Eurographics Association.2009:35-42.
[34] Goswami P, Makhinya M, Bosch J, et al. Scalable Parallel Out-of-core TerrainRendering[C]//Proceedings of the10th Eurographics Conference on Parallel Graphics andVisualization. Ping: Eurographics Association.2010:63-71.
[35] Ulrich T. Rendering Massive Terrains Using Chunked Level of Detail Control[R]. Course Notesof ACM SIGGRAPH. San Antonio: SIGGRAPH,2002,35.
[36]卓亚芬. ChunkedLOD—海量地形的实时绘制系统[D].杭州:浙江大学,2004:35-39.
[37]李胜,冀俊峰,刘学慧,等.超大规模地形场景的高性能漫游[J].软件学报,2006,17(3):535-545.
[38] Dick C, Schneider J, Westermann R. Efficient Geometry Compression for GPU-based Decodingin Realtime Terrain Rendering[J]. Computer Graphics Forum,2009,28(1):67-83.
[39] Dick C, Kr Ger J, Westermann R. GPU Ray-casting for Scalable TerrainRendering[C]//Proceedings of Eurographics. Genve: EUROGRAPHICS Associations,2009,28:43-50.
[40] Dick C, Kruger J, Westermann R. GPU-Aware Hybrid Terrain Rendering[J]. InternationalJournal of Computer Information Systems and Industrial Management Applications,2011,3:820-827.
[41] Ammann L, Gnevaux O, Dischler J-M. Hybrid Rendering of Dynamic Heightfields UsingRay-Casting and Mesh Rasterization[C]//Proceedings of Graphics Interface2010.Ottawa:Canadian Information Processing Society.2010:161-168.
[42]李白云,赵春霞. GPU实时构建四叉树的快速地形渲染算法[J].计算机辅助设计与图形学学报,2010,22(12):2259-2264.
[43]张豫南,王冬,夏乙,等.瓦片块四叉树动态地形细节层次算法[J].兵工学报,2011,32(11):1411-1415.
[44] Yusov E, Shevtsov M. High-Performance Terrain Rendering Using Hardware Tessellation[J].Journal of WSCG,2011,19(1):85-92.
[45] Asirvatham A, Hoppe H. Terrain Rendering Using GPU-based Geometry Clipmaps[M]. GPUGems, Boston: Addison-Wesley,2005:27-45.
[46] Dirk Feldmann K H. GPU Based Single-Pass Ray Casting of Large Heighfields UsingClipmaps[OL].[2013-02-04] http://viscg.uni-muenster.de/publications/2012/FH12/.
[47] Schneider J, Westermann R U. GPU-friendly High-quality Terrain Rendering[J]. Journal ofWSCG.2006,14(3):49-56.
[48] Wahl R, Massing M, Degener P, et al. Scalable Compression and Rendering of Textured TerrainData [J]. Journal of WSCG.2004,12(3):521-528.
[49] Purnomo B, Bilodeau J, Cohen J D, et al. Hardware-Compatible Vertex Compression UsingQuantization and Simplification[C]//Proceedings of the ACM SIGGRAPH/EUROGRAPHICSConference on Graphics hardware. Los Angeles: ACM.2005:53-61.
[50] Yoon S-E, Lindstrom P. Mesh Layouts for Block-Based Caches[J]. IEEE Transactions onVisualization and Computer Graphics.2006,12(5):1213-1220.
[51] Yoon S-E, Lindstrom P. Random-Accessible Compressed Triangle Meshes[J]. IEEE Transactionson Visualization and Computer Graphics.2007,13(6):1536-1543.
[52] Livny Y, Kogan Z, El-Sana J. Seamless Patches for GPU-Based Terrain Rendering[J]. The VisualComputer,2009,25(3):197-208.
[53] Livny Y, Sokolovsky N, Grinshpoun T, et al. A GPU Persistent Grid Mapping for TerrainRendering[J]. The Visual Computer,2008,24(2):139-153.
[54] Roth S D. Ray Casting for Modeling Solids[J]. Computer Graphics and Image Processing,1982,18(2):109-144.
[55] Johanson C. Real-Time Water Rendering-Introducing the Projected Grid Concept [D]. Lund:Lund University,2004.
[56] Tevs A, Ihrke I, Seidel H-P. Maximum Mipmaps for Fast, Accurate, and Scalable DynamicHeight Field Rendering[C]//Proceedings of the2008Symposium on Interactive3D GraphicsAnd Games. Redwood: ACM.2008:183-190.
[57] Hubert Nguyen. GPU精粹3[M].杨柏林,陈根浪,王聪译.北京:清华大学出版社,2007:409-428.
[58]陈静,龚健雅,朱欣焰,等.分布式虚拟地形场景仿真研究[J].系统仿真学报,2007,19(5):1057-1060,1081.
[59]徐正全,高路,李忠民,等.基于非结构化P2P网络的地形数据存储系统[J].武汉大学学报(信息科学版),2010,35(1):122-125.
[60]王永君,龚健雅.用于大范围虚拟地形环境的动态场景管理方法[J].测绘学院学报,2003,20(3):231-234.
[61]朱庆,赵杰,钟正,等.基于规则格网DEM的地形特征提取算法[J].测绘学报,2004,33(1):77-82.
[62]许妙忠.大规模地形实时绘制的算法研究[J].武汉大学学报(信息科学版),2005,30(5):392-395.
[63]喻占武,郑胜,李忠民.一种混合式P2P下的大规模地形数据传输机制[J].测绘学报,2008,37(2):243-249.
[64]潘少明,喻占武,李锐.基于主动缓存的P2P海量地形漫游瓦片调度算法[J].测绘学报,2009,38(3):236-241,249.
[65]赵友兵,石教英,周骥,等.一种大规模地形的快速漫游算法[J].计算机辅助设计与图形学学报,2002,14(7):624-628.
[66]肖俊,庄越挺,吴飞.基于细节层次与最小生成树的三维地形识别与检索[J].软件学报,2003,14(11):1955-1963.
[67]施松新,叶修梓,张三元,等.基于分块的大规模地形实时渲染方法[J].浙江大学学报(工学版),2007,41(12):2002-2006，2016.
[68]施松新,张引,叶修梓,等.大规模地形场景流式渐进传输[J].浙江大学学报(工学版),2008,42(11):1862-1867.
[69]夏杰,陈奇.基于静态LOD的海量地形绘制中的接缝算法[J].计算机工程与设计,2010,31(22):4847-4850.
[70] Moreton H. Watertight Tessellation Using Forward Differencing[C]//Proceedings of the ACMSIGGRAPH/EUROGRAPHICS Workshop on Graphics Hardware. Los Angeles: ACM.2001:25-32.
[71] Munkberg J, Hasselgren J, Akenine-Moller T. Non-Uniform FractionalTessellation[C]//Proceedings of the23rd ACM SIGGRAPH/EUROGRAPHICS Symposium onGraphics hardware. Switzerland: Eurographics Association Aire-la-Ville.2008:41-45.
[72] Schwarz M, Stamminger M. Fast GPU-based Adaptive Tessellation with CUDA[J]. ComputGraph Forum,2009,28(2):365-374.
[73] Bailey M, Cunningham S. GPU Shaders for OpenGL4.0[M]. SIGGRAPH Asia2011Courses.Hong Kong: ACM.2011:1-89.
[74] Boubekeur T, Schlick C. Generic Mesh Refinement on GPU[C]//Proceedings of the ACMSIGGRAPH/EUROGRAPHICS Conference on Graphics hardware. Los Angeles:ACM.2005:99-104.
[75] Boubekeur T, Schlick C. A Flexible Kernel for Adaptive Mesh Refinement on GPU[J]. ComputerGraphics Forum,2008,27(1):102-114.
[76] Lorenz H, Dollner J. Dynamic mesh refinement on GPU using geometry shaders[J]. Journal ofWSCG,2008,16(1):97–104.
[77] Dyken C, Reimers M, Seland J. Real-Time GPU Silhouette Refinement Using AdaptivelyBlended Bézier Patches[J]. Computer Graphics Forum.2008,27(1):1-12.
[78] Dyken C, Reimers M, Seland J. Semi-Uniform Adaptive Patch Tessellation[J]. ComputerGraphics Forum,2009,28(8):2255-2263.
[79] Amresh A, Funfzig C. Semi-Uniform,2-Different Tessellation of Triangular ParametricSurfaces[C]//Proceedings of the6th International Conference on Advances in Visual Computing-Volume Part I. Heidelberg: Springer-Verlag Berlin.2010:54-63.
[80]王旭,阳新,王志铭.在GPU上实现地形渲染的自适应算法[J].计算机辅助设计与图形学学报,2010,22(10):1741-1750.
[81] Vlachos A, Peters J, Boyd C, et al. Curved PN triangles[C]//Proceedings of the2001Symposiumon Interactive3D Graphics. New York:ACM.2001:159-66.
[82] Yeo Y I, Ni T, Myles A, et al. Parallel Smoothing of Quad Meshes[J]. The Visual Computer,Springer-Verlag New York,2009,25(8):757-769.
[83] Boubekeur T, Alexa M. Phong Tessellation[J]. ACM Transactions on Graphics,2008,27(5):1-5.
[84]温佩芝,吴晓军,吴成柯.自适应细分曲面算法及在快速成型数据处理中的应用[J].计算机集成制造系统,2007,13(3):608-614.
[85]李胜,黄鑫,汪国平.基于GPU的视点相关自适应细分[J].计算机辅助设计与图形学学报,2007,19(4):409-414.
[86]张湘玉.基于细分的曲线曲面变形技术研究[D].南京:南京航空航天大学,2010:60-66.
[87] Hollander, M. Boubekeur, T. Synthesizing Subdivision Meshes using Real Time Tessellation[C]//Proceedings of the201018th Pacific Conference on Computer Graphics and Applications. LosAlamitos: IEEE Computer Society Press,2010:46-53.
[88]唐敏,童若锋,董金祥.基于GPU的曲面自适应细分[J].浙江大学学报(工学版),2008,42(7):1145-1149,1217.
[89] Loop C, Schaefer S, Ni T, et al. Approximating Subdivision Surfaces with Gregory Patches forHardware Tessellation[J]. ACM Transactions on Graphics,2009,28(5):1-9.
[90] Ni T. Efficient Substitutes for Subdivision Surfaces in Feature-Quality Games[M]. ACMSIGGRAPH ASIA2010Courses. Seoul:ACM.2010:1-77.
[91] Tatarinov A. Reyes Using DirectX11[M]. ACM SIGGRAPH2010Talks. Los Angeles:ACM.2010:1-10.
[92] Gobbetti E, Marton F, Rodriguez M B, et al. Adaptive Quad Patches: an Adaptive RegularStructure for Web Distribution and Adaptive Rendering of3D Models[C]//Proceedings of the17th International Conference on3D Web Technology. Los Angeles:ACM.2012:9-16.
[93] Fisher M, Fatahalian K, Boulos S, et al. DiagSplit: Parallel, Crack-Free, Adaptive Tessellationfor Micropolygon Rendering[J]. ACM Transactions on Graphics,2009,28(5):1-10.
[94] Niebner M, Loop C, Meyer M, et al. Feature-Adaptive GPU Rendering of Catmull-ClarkSubdivision Surfaces[J]. ACM Transactions on Graphics,2012,31(1):1-11.
[95] Schafer H, Prus M, Meyer Q, et al. Multiresolution Attributes for TessellatedMeshes[C]//Proceedings of the ACM SIGGRAPH Symposium on Interactive3D Graphics andGames. Costa Mesa: ACM.2012:175-82.
[96] Cook R L. Shade Trees[J]. SIGGRAPH Computer Graphics,1984,18(3):223-231.
[97]宋滢.非均质半透明材质的绘制及编辑算法研究[D].杭州:浙江大学,2009:18-20.
[98] Wang L, Wang X, Tong X, et al. View-Dependent Displacement Mapping[J]. ACM Transactionson Graphics,2003,22(3):334-339.
[99] Livny Y, Bauman G, El-Sana J. Displacement Patches for View-Dependent Rendering[J]. TheVisual Computer,2011,28(3):247-263.
[100] Wang X, Tong X, Lin S, et al. Generalized Displacement Maps[C]//Proceedings of the FifteenthEurographics Conference on Rendering Techniques. Ping: Eurographics Association.2004:227-233.
[101] Gu X, Gortler S J, Hoppe H. Geometry Images[J]. ACM Transactions on Graphics,2002,21(3):355-361.
[102] Losasso F, Hoppe H, Schaefer S, et al. Smooth Geometry Images[C]//Proceedings of the2003Eurographics/ACM SIGGRAPH Symposium on Geometry processing. Aachen: EurographicsAssociation.2003:138-145.
[103] Praun E, Hoppe H. Spherical Parametrization and Remeshing[J]. ACM Transactions on Graphics,2003,22(3):340-349.
[104] Sander P V, Wood Z J, Gortler S J, et al. Multi-Chart Geometry Images[C]//Proceedings of the2003Eurographics/ACM SIGGRAPH Symposium on Geometry processing. Aachen:Eurographics Association.2003:146-155.
[105] Carr N A, Hoberock J, Crane K, et al. Rectangular Multi-Chart GeometryImages[C]//Proceedings of the Fourth Eurographics Symposium on Geometry Processing.Cagliari: Eurographics Association.2006:181-190.
[106] Yao C Y, Lee T Y. Adaptive Geometry Image[J]. IEEE Transactions on Visualization andComputer Graphics,2008,14(4):948-960.
[107] Feng W W, Kim B U, Yu Y, et al. Feature-Preserving Triangular Geometry Images forLevel-Of-Detail Representation of Static And Skinned Meshes[J]. ACM Transactions onGraphics,2010,29(2):1-13.
[108] Wagner D. Terrain Geomorphing in the Vertex Shader [M]. Plano: Wordware Publishing.2004:1-12.
[109] Kooima R, Leigh J, Johnson A, et al. Planetary-Scale Terrain Composition[J]. IEEE Transactionson Visualization and Computer Graphics,2009,15(5):719-733.
[110] Roberts D A K M, Hardy A. Level of Detail for Terrain Geometry Images[C]//Proceedings of the5th International Conference on Computer Graphics, Virtual Reality, Visualisation andInteraction in Africa. Grahamstown: ACM.2007:25-30.
[111] Niski K, Purnomo B, Cohen J. Multi-Grained Level of Detail Using a Hierarchical SeamlessTexture Atlas[C]//Proceedings of the2007Symposium on Interactive3D Graphics and Games.Seattle: ACM.2007:153-60.
[112] Strugar F. Continuous Distance-Dependent Level of Detail for Rendering Heightmaps[J]. Journalof Graphics, GPU, and Game Tools,2010,14(4):57-74.
[113] Amara Y, Meunier S, Marsault X. A GPU Framework for the Visualization and on-the-FlyAmplification of Real Terrains[C]//Proceedings of the3rd International Conference on Advancesin Visual Computing. Lake Tahoe: Springer-Verlag.2007,1:586-597.
[114] Amara Y, Marsault X. A GPU Tile-Load-Map Architecture for Terrain Rendering: Theory andApplications[J]. The Visual Computer,2009,25(8):805-824.
[115]张燕燕,黄其涛,韩俊伟.基于提升小波的大地形累进压缩及实时渲染[J].计算机辅助设计与图形学学报,2010,22(8):1352-1359.
[116]刘迎,刘学慧,吴恩华.基于可变模版的三角网格拓扑压缩[J].软件学报,2008,19(4):1016-1025.
[117] Isenburg M, Lindstrom P, Snoeyink J. Streaming Compression of TriangleMeshes[C]//Proceedings of the Third Eurographics Symposium on Geometry Processing. Vienna:Eurographics Association.2005:111-120.
[118] Griebel M, Zumbusch G. Parallel Multigrid in an Adaptive PDE Solver Based on Hashing andSpace-Filling Curves[J]. Parallel Computing,1999,25(7):827-43.
[119] Laurent B, Jelena K, Martin V. Quadtrees for Embedded Surface Visualization: Constraints andEfficient Data Structures[J]. International Conference on Image Processing,1999,8(2):487-491.
[120]马建平,罗笑南,陈渤,等.面向移动终端的三角网格逆细分压缩算法[J].软件学报,2009,20(9):2607-2615.
[121] Gouraud H. Continuous Shading of Curved Surfaces[J]. IEEE Transactions on Visualization andComputer Graphics,1971,20(6):623-629.
[122] Phong B T. Illumination for Computer Generated Pictures[J]. Communications of the ACM,1975,18(6):311-317.
[123]吴亚峰. Android3D游戏开发技术宝典--OpenGL ES2.0[M].北京:人民邮电出版社,
2012:94-97.