在非擬真成像環境中模擬畫布上的體積視覺效果

Synthesizing the NPR Volumetric Visual Effects on Canvas

陳沂顯(Yi-Hsien Chen)

指導教授 ： 陳履恆

國立暨南國際大學/科技學院/資訊工程學系/碩士(2009年)

https://doi.org/10.6837/NCNU.2009.00110

摘要

非擬真成像是計算機圖學領域裡一門很重要的議題，它可以呈現出有別於相片擬真的效果。三維模型導向非擬真成像系統裡最重要的特性是－利用三維模型的空間幾何資訊來輔助筆觸的計算。舉例來說，模型的輪廓、骨架結構、與觀者的距離等，皆可以幫助我們決定如何下筆以保留物件原有特性，甚至突顯它的特性。

本研究借助非擬真成像在顏色呈現上的長處，結合筆觸合併和素描建模概念來產生俱有積體視覺效果的作品，尤以油畫的厚塗法、雕塑的黏土浮雕等。換言之，本研究提出的系統可以幫助筆者模擬簡單地創作手法來產生具有體積效果的顏料、黏土雕塑等媒材，以三維場景畫作的方式呈現。

關鍵字

計算機圖學 ； 非擬真成像 ； 筆觸合併 ； 素描建模 ； 油畫 ； 厚塗法 ； 雕塑 ； 黏土浮雕 ； 油畫顏料

並列摘要

NPR (Non Photo-Realistic) is an important issue in Computer Graphics. It can present in a totally different style from realistic methods. In this paper, we takes the advantage of 3D NPR system in color presentation, and apply stroking merge and sketch-based modeling to synthesizing art works with volumetric effect, such as: oil-painting pigments with impasto style, relief sculpture, clay relief and so on.

As one of the characteristic features of 3D model oriented NPR, the geometric information is extracted from 3D models for calculating the appearance properties of each stroke. These important and useful clues include silhouette, distance, and skeleton structure of objects. Through our prototype system, several common skills of creating art works are simulated for rendering 3D scene. As shown in the experiment results, our 3D NPR system creates interesting and vivid oil-painting, clay relief liked images.

並列關鍵字

Computer Graphics ； Non-Photorealistic Rendering ； Stroking Merge ； Sketch-Based Modeling ； Oil Painting ； Impasto ； Clay Relief ； Relief Sculpture ； pigment.

參考文獻

1. Aaron Hertzmann, "Painterly Rendering with Curved Brush Strokes of Multiple Sizes", SIGGRAPH 98, 1998, 453-460, 1998.

2. Aaron Hertzmann, Ken Perlin , "Painterly Rendering for Video and Interaction", Proc. of Non-Photorealistic Animation and Rendering 2000, 2000.

3. Aaron Hertzmann, “Fast paint texture”. Proc. of Non-Photorealistic Animation and Rendering 2002, 91–96, 2002.

4. Alexander Belyaev, “Mesh Smoothing and Enhancing. Curvature Estimation”, 2006.

5. Cheng-Tseng Ling, “Automatic Generation of Pencil Sketch Drawing from Photos”, National Chiao Tung University, Master thesis, 2005.