基於疊代最佳化之網格參數化及其於三維著色系統之應用

Abstract

三維著色為一讓使用者直接於三維表面著色之程序。著色筆觸儲存於一張由網格參數化技術產生之二維貼圖。傳統三維著色的系統，網格參數化為事先產生，此參數化平面即為三維模型之材質貼圖。在著色過程中，網格參數化是固定的，並不會根據繪圖筆觸，於顏色訊號變化較為劇烈之處給予較多的貼圖取樣。為了提高三維著色系統的效能，必須針對使用者的繪圖筆觸，於著色過程中調整網格參數化使得顏色變化劇烈的區域得到較多的貼圖取樣，且須在互動時間內完成。在這篇論文中，我們提出一個基於疊代最佳化之網格參數化架構。於互動時間內，針對顏色訊號變化較為劇烈的區域在貼圖區域上給予較多的取樣空間。

關鍵字：網格參數化、三維著色系統、材質貼圖產生

Surface painting is a procedure that allows the users to paint onto a surface directly. The painting strokes are stored in a texture via surface parameterization techniques. In current surface painting systems, the underlying surface parameterization is fixed during the painting process. Such a parameterization is not sensitive to the frequency spectrum of the color signal introduced by painting strokes. To associate the regions of higher color signal variation with more texture samples, we need to do the re-parameterization according to users strokes at interactive rates. In this thesis, we propose a re-parameterization scheme that is based on an iterative-optimization aiming to allocate more texture samples for regions of high signal variation and to perform at an interactive rate as well. Keywords: surface painting, surface parameterization, texture generation.