Automated Embroidery Prototype Simulation: an Independent Study in 3d Computer Graphics Rendering

OVERVIEW In the automated embroidery business, the ability to present a client with a tangible design prototype is highly desirable. However, the cost of materials involved with creating such prototypes increases sharply when one takes into consideration the thousands of possible combinations of thread types and colors, stitch patterns, and applications of a particular embroidery design. I define applications of an embroidery design as what the design will eventually be embroidered onto, such as hats, coats, shirts, and other articles of clothing. Thus, the simulation of these prototypes using three-dimensional models can allow for higher efficiency at lower costs. The goal of this project is to take a bitmap, created in a stitch simulator, as input and apply it as a texture image to a Bezier patch. A user, to create the illusion that it is in the same orientation and shape as an object in the two-dimensional background image, then manipulates the patch, or mesh. A final image is produced by rendering this mesh with the texture map, thereby creating the illusion that the design has been embroidered onto some article of clothing in the background image. Throughout the course of the project, different students have worked on different portions of the code. Mo Chen fashioned the transformation matrices and many different aspects of manipulating the mesh, such as scaling and distortion. Joseph Pamer worked on the rendering process, including texture mapping and bitmap loading. Last semester I designed the graphical user interface (GUI) for the program and aided Joe and Mo in their portions. This semester, I rearranged and corrected a large amount of the preexisting code, redesigned the GUI, and added new processes for texture mapping; specifically, a scanline algorithm used for obtaining the exact texture values for a given output pixel. This semester as well, Kenny worked on implementing a different texture mapping filtering routine based upon an article by Feibush and Cook. He also improved the process of converting between (x,y) screen coordinates and (u,v) texel coordinates. The renderer is responsible for the world, view, and projection transformations that display the mesh. This is accomplished by storing the viewing system parameters and updating stored transforma tion matrices whenever the parameters are altered. A given mesh transforms its own coordinates by sending each vector to the renderer, and then stores the new coordinates in a separate array so that the 3D coordinates are not destroyed. The …