Study On The System Of Textiles Design & 3D Dressing Rendering

In this paper, the computer-integrated system, aimed at textiles design and 3D dressing rendering, is constructed with making use of theories of textiles design and 3D dressing modeling, combining the means of mathematics matrix computing, computer graphics and digital image technology. Some investigations on technology issues, such as automatic generation of weaves, simulation of fabric, modeling of 3D human body and garment, and texture mapping of fabric to garment, are also made.The algorithms for automatic generation of weaves, which is a basic item of textiles integrated system, are developed in detail. For single-layer fabric, weaves are re-grouped for the purpose of mathematical description, and they fall into three groups: regular weaves, pre-regular weaves and irregular weaves. And then the mathematical models of every group are established, the parameters and the qualifications of weaves automatic generation are offered too. For multi-layer fabric, Kronecker product and yarn grouping of different layers according to the arrangement ratio are combined together to explore the mathematical model of weaves automatic generation. The qualifications of forming the multi-layer weaves are also discussed.Fabric simulation is an item of more difficult technology. In this paper, several typical fabric simulation methods are proposed. First, the true size fabric simulation method with the different arrangements of yarn color and fine, warp and weft density and weave structure is analyzed, and matching scheme among yarn fine, fabric density and screen resolution is also designed. Based on the scanned and processed yarn images, the fabric that uses real effect yarns is simulated through superposing the yarn axis with the position calculated by the fabric density. By setting the parameters of fluff length, fluff direction, fluff density and fluff control points, the fabric fluff appearance simulation is offered by fitting lower order Bezier curves. The simulation of pattern fabric that shows the weave structure is proposed through calculating the Kronecher product of a shading dithering matrix and a continuation matrix and through changing the color or gray scale of patternfabric image. By means of the analysis of yarn section shape, yarn curve shape and relative positions among the yarns in fabric, the real topology structure of the yarns in fabric is explored and fabric simulation is achieved with the setting of light model parameters.For the 3D human body .and garment modeling and surface fitting, a human body database and a three-layer feature model are set up based on the human body measurement data. The class inheritance relations of human body are established according to three-layer feature model: object layer, feature layer and geometry layer. Human surface control points in geometry layer are fitted with NURBS surface fitting method. The obtaining method of 3D modeling points of garment is offered by calculating the offset value. Moreover, as to lighting process of 3D model, the paper gives the discussions with the theories of lighting model, color mode, surface material attributes, etc..For 3D dressing rendering of fabric, the paper states the theory of 2D texture mapping onto 3D surface. And then, the mapping relations of fabric texture toward garment surface and shading/texturing model are studied, the graphic transformations and texture mip-mapping technology, which concern the 3D dressing display, are put forward too.The object-oriented method is adopted to analyze and design the bulky integrated system. All primary object models and relations among them are clearly recognized. The status flows and the data flows of whole system are plotted by using the dynamic model and function model respectively.