數位藝術是指透過數位科技的軟體工具產生的藝術品，其形式包括圖像、影像、文字、音頻或以其他形式存在的數位藝術作品。相較於傳統藝術作品，它的表現形式更加豐富，更便於傳播、儲存和複製。本篇專注於加拿大數位藝術家Patrick Seymour 作品，Patrick Seymour的作品多以線條表示圖像內容，並以改變線條的形式，如線條流向、曲線弧度以及線條粗細的變化，讓黑底白線的作品，有躍然紙上的立體效果。
本篇透過張量場的設計將使用者的輸入量化，並以此作為產生線條流向的參考。以往關於張量場設計的圖學研究，一般多以編輯奇異點的方式，此種輸入方式對一般的使用者而言不是很直覺，輸出往往無法得到使用者預期的結果；而在表現的形式上，則是多將張量場的計算結果作為材質貼圖的參考。而本篇為了達到藝術家作品效果，將張量場以流線的形式呈現。為了提供便利的使用工具，我們設計了一個互動系統讓使用者進行設計。本篇論文基於一張手動分割的圖片，以各個區塊為單位，讓使用者手繪線條，與輸入線條參數，如線條間隔距離、分布密度、流線寬度變化。透過使用者的流向引導產生出張量場，並以此張量場作為產生流線的依據，最後產生一張如同藝術家的線條藝術作品。

Digital art is an artistic work or practice that uses digital technology as an essential part of the creative or presentation process. Various names have been used to describe the process including computer art and multimedia art, and digital art is itself placed under the larger umbrella term new media art.
This digital art work is motivated by a French artist Patrick Seymour, he makes an image pop out of the window with nothing but white lines on the background. His creations appear to be 3D as he varies the thickness, curve, and direction of each line to achieve an astounding level of depth.
Our system converts each user specification into a tensor field. With bidirectional tensor information, streamlines can be trace to visualize the field. In the past works, design of tensor field usually comes with editing degenerate points, and that’s not quite instinct for novice users. And most of the final presentation uses streamline as navigation for textures in art form. In this work, the presentation comes with just streamlines. For this purpose, we have to control streamline placement precisely to reach the artist’s original work. For the convenience, we design an interactive system for novice users.
In this work, we input a segmented picture, let users sketch strokes to guide the tensor field in each segment. With parameters such as streamline separation, saturation, and thickness of the streamline, we create artist-like hypnotic line art works.

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