在電腦繪圖領域中，在此之前關於中國水墨風格的研究，多處於靜態水墨畫效果的呈現，而無法提供與使用者即時互動的效果。本論文之研究，即希望提供一套中國水墨畫風格的繪圖系統，將不同的三維模型以水墨線條呈現，並能與使用者即時互動，使用者可以即時任意轉動、拉近、拉遠瀏覽此模型，並且透過參數的調整，選擇濃、淡、乾、濕其喜好的水墨筆觸效果。
本論文提出解決在輪廓線裹上畫家筆觸遇到最大的兩個問題：決定可見輪廓線(Visibility)及串連可見輪廓線片段(Linking)。在決定可見輪廓線時，我們利用Z-buffer的資訊，較傳統作法受限於從顯示卡讀取資料速度上的瓶頸，我們的作法在速度上有較好的表現。另外，在連結可見輪廓線片段的問題上，我們提出新的概念，利用頂點鄰近三角形資訊的方法，而非傳統在影像上搜尋紀錄鄰近輪廓線片段的作法。
我們結合3D Texture及Multi-Texture硬體加速產生的水墨筆觸貼圖，使三維模型可以類似國畫技法中的白描效果即時呈現在使用者眼前，並且也適合未來與整合式的繪圖系統相結合。此外，也針對輪廓線在裹上筆觸貼圖後，在轉動時有筆觸跳動不一致的問題，提出我們的作法來加以改善，並且對於繪圖速度並無顯著的效能負擔。在模型內部區域的上色，我們使用Pixel Shader及Noise的微調，產生類似國畫中水墨渲染的效果。最後的作品效果可以達到15FPS以上，可以與使用者互動的顯示速度。

This paper presents a automatic method to render 3D models in Chinese painting style. Most previous research on Chinese painting style has focused on the effect of 2D static scenes, and couldn’t offer real-time rendering speed. Therefore, we propose an Chinese painting style rendering system takes 3D common model as input. A user can adjust suitable parameters to generate different brush styles as his hobby, and see the result in real time.
There are two common problems to render silhouette with stylized strokes. The first problem is how to determine visibility of silhouettes. We utilize the information of Z-buffer and have better performance than the traditional methods. The second problem is to how to link those visible silhouette segments into paths. We propose a new idea to make use of the one ring triangle indices of the model vertices.
We both combine 3D Texture and Multi-Texture hardware accelerated techniques to generate various brushes with Chinese painting style. We apply those brushes over linked silhouette paths to simulate Chinese painting strokes. In this paper, we also explain how to interactively render stylized silhouettes with frame-to-frame coherence, and our method can work at interactive rates. In the interior shading of models, we use the pixel shader provided by Nvidia’s CG language to simulate the Bal-muk effect in Chinese painting. The final result of our system can render at an interactive speed (higher than 15 FPS).

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