基于半规则纹理合成的流场可视化技术

Flow Visualization by Near-Regular Texture Synthesis

直接利用半规则纹理本身蕴涵的方向信息对流场进行可视化,结果直观有效,而且适用的纹理范围广泛,丰富了流场可视化的手段.首先应用基于块的二维方向纹理合成方法生成第一帧图像,随着流体的流动,每一小块的4个顶点移动到新的位置.然后将原有的纹理映射到新的四边形上,同时计算出每个点的变形程度.如果某点变形过大,那么把该点标为无效点,重新合成.最后,一帧帧连续合成的纹理组成一个流场可视化的动画.

In this paper, a method is proposed to use the directional information of a near-regular texture to generate a moving texture for animated visualization of a flow field. By the method, we use the patchbased method to synthesize the first frame. To generate the next frame, the four corners of each patch P arc moved along the flow to define a new quadrilateral P＇. The texture of P is then mapped into P＇. We then use a deformation matrix defined by the Jacobian matrix of the mapping from P to P＇ to track the degree of deformation of each pixel. When the texture deformation at a pixel is beyond a certain threshold, the pixel will be marked as invalid and re-synthesized. The above step is repeated to generate all subsequent frames in a coherent manner. Besides adding to the variety of flow visualization techniques, our method is also the first capable of synthesizing a moving texture from a near-regular sample texture.