运用局部纹理映射加速曲面纹理合成

Curve Surface Texture Synthesis by Local Texture Mapping

基于样图的纹理合成方法能够在网格曲面上合成高质量纹理,但合成速度有待进一步提高,对此提出一种运用局部纹理映射加速曲面纹理合成的算法.首先以三角形法向量、切向矢量与纹理尺度为约束,将三角网格曲面分割为一系列映射区与合成区;然后用基于块的平面纹理合成方法生成大面积样图,用调和映射方法对映射区进行纹理映射;最后采用基于三角块的合成方法生成合成区纹理.实验结果表明,该算法对一般的随机性纹理与半结构性纹理具有很高的合成质量,能够控制纹理方向与尺度的变化.由于大部分三角形的纹理通过局部纹理映射得到,仅需要合成少数三角形的纹理,纹理合成过程得到大幅度地加速.

High quality textures can be generated on mesh surfaces by texture synthesis from samples, however the synthesis performance should be further improved. By combining texture synthesis with the local texture mapping, the paper presents a novel algorithm to speed up the process of texture synthesis. By the algorithm, the surfaces are first divided into a series of mapping areas and synthesis areas using the constraints of the triangles＇ normal and texture attributes. Then the mapping areas are textured by harmonic mapping from the 2D mapping sample, by a patch-based synthesis method. Finally, the synthesis areas are textured by a triangle-based synthesis method. The experimental results show that the algorithm renders textures on curve surfaces with good continuity feature and little distortion, and at the same time the user can simply control the orientation and the scale of textures according to the user＇s requirement. As most of the triangles are directly textured by mapping, and only a few triangles need to be textured through synthesis, the texturing process performance is greatly improved.