图1 VR环境中画刷形态((a)球形画刷；(b)射线画刷)

Fig. 1 Paint brush form in VR environment ((a) Spherical brush; (b) Radial brush)

图2 不同画刷模式在不同区域的雕刻效果((a)原始狗模型背部；(b)原始狗模型颈部；(c)球形画刷雕刻背部区域；(d)球形画刷雕刻颈部区域；(e)射线画刷雕刻背部区域；(f)射线画刷雕刻颈部区域)

Fig. 2 The sculpting effects of different brush modes in different areas ((a) Dorsal area of the original dog model; (b) Neck area of the original dog model; (c) Sculpting the dorsal area with a spherical brush; (d) Sculpting the neck area with a spherical brush; (e) Sculpting the dorsal area with a radial brush; (f) Sculpting the neck area with a radial brush)

图3 长边分割操作((a)分割前结构；(b)分割后结构)

Fig. 3 Long edge division operation ((a) Structure before division; (b) Structure after division)

图4 短边折叠操作((a)折叠前结构；(b)折叠后结构)

Fig. 4 Short edge folding operation ((a) Structure before folding; (b) Structure after folding)

图5 兔子模型优化(亏格为0) ((a)原始兔子模型；(b)优化后的兔子模型)

Fig. 5 Optimization of the bunny model (genus=0) ((a) Original bunny model; (b) Optimized bunny model)

图6 杯子模型优化(亏格不为0) ((a)原始杯子模型；(b)优化后的杯子模型)

Fig. 6 Optimization of the cup model (genus?0) ((a) Original cup model; (b) Optimized cup model)

图7 同一个球上的Inflate和Deflate操作

Fig. 7 Inflate and Deflate operations on the same sphere ((a) Inflate; (b) Deflate)

图8 同一初始模型上的不同操作((a)膨胀；(b)挤压；(c)压平；(d)平滑)

Fig. 8 Different operations on the same initial model ((a) Inflate; (b) Deflate; (c) Flatten; (d) Smooth)

图9 Inflate操作引起的拓扑融合((a)融合前结构；(b)融合后结构)

Fig. 9 Topological fusion caused by Inflate operation ((a) Structure before fusion; (b) Structure after fusion)

图10 不相邻2个顶点的合并((a)合并前结构；(b)合并后结构)

Fig. 10 Merger of two non-adjacent vertices ((a) Structure before merger; (b) Structure after merger)

图11 有无步长限制下的网格情况((a)无步长限制；(b)有步长限制)

Fig. 11 Grid situation with or without step size limit ((a) Without step size limit; (b) With step size limit)

图12 基于网格变形的自由画刷生成模型((a)原始模型；(b)生成的模型)

Fig. 12 Model generated by Free Brush based on grid deformation ((a) Original model; (b) Generated model)

图13 目标模型上点移动后结果((a)点移动后的目标模型；(b)待融合模型局部)

Fig. 13 Result after moving points on the target model((a) Target model after point movement; (b) Partial area of the model to be integrated)

图14 基于网格融合的自由画刷生成模型((a)原始模型；(b)生成的模型)

Fig. 14 Model generated by Free Brush based on grid fusion ((a) Original model; (b) Generated model)

图15 手柄界面((a)左手手柄；(b)右手手柄)

Fig. 15 The handle interface ((a) The left-hand handle; (b) The right-hand handle)

图16 有无拓扑自动融合机制下的网格((a)模型内部相交；(b)模型内部无相交；(c)模型网格错乱；(d)模型网格无错乱；(e)错乱网格放大；(f)无错乱网格放大)

Fig. 16 Mesh with or without automatic topology fusion mechanism ((a) Internal intersection within the model; (b) No internal intersections within the model; (c) The model grid with distortion; (d) The model grid without distortion; (e) Magnified view of the grid with distortion; (f) Magnified view of the grid without distortion)

图17 有无位置合理性检测的网格情况((a)非法操作；(b)模型破面；(c)合法操作；(d)模型无破面)

Fig. 17 Mesh with and without position rationality detection ((a) Illegal operation; (b) Model with broken mesh; (c) Legal operation; (d) Model without broken mesh)

图18 已有模型上创建模型((a)原始模型；(b)雕刻模型)

Fig. 18 Model created based on existing models ((a) Original model; (b) Sculpted model)

图19 上色的灯笼模型

Fig. 19 Colored lantern model

图20 用户自主创建的类蝴蝶生物模型

Fig. 20 User-created butterfly-like creature model

图21 使用自由画刷融合2个模型得到的新模型

Fig. 21 New model obtained by blending two models using freehand brush

图22 花瓶雕刻过程((a)创建花瓶主体；(b)添加把手；(c)创建悬空圆环；(d)添加整体装饰)

Fig. 22 Vase sculpting process ((a) Create the basic shape of vase; (b) Add handles; (c) Create suspended ring; (d) Add overall decoration)