蛋殼雕刻藝術(Egg Carving Art)，是在飛禽類的蛋殼上進行雕琢(engraving)而形成的一種民間手工藝術品，雕琢的方式有很多種：繪畫、淺浮雕(bas relief)、陽雕、鏤空雕等，也有結合不同種雕琢方式製作而成的蛋雕。蛋殼雕刻藝術的製作過程通常需要幾個主要步驟:1.在雞蛋頂部或是底部鑽出一個孔洞，然後將雞蛋裡面的蛋液和蛋黃傾倒出來。2.將中空的蛋殼沖洗乾淨以後，用鉛筆在蛋殼表面根據草圖進行構圖繪畫。3.利用各種電磨雕刻工具在蛋殼表面根據構圖進行切割或是打磨。
雖然在蛋殼表面上可以雕刻任意的花紋或樣式，本論文著重在其中一種風格藝術:艾薛爾拼圖藝術(escher tessellation)，這種藝術透過將不同形狀的圖形緊密的貼合並且重複地平舖(tile)在平面上形成具有幾何以及數學意義的花紋圖樣，並融合錯視(perception illlusion)的效果使圖形充滿複雜奇幻的變形結構。
相比現實中製作蛋殼雕刻藝術的困難，現今電腦中存在許多方便的三維模型建模軟體，使用者可以借助軟體建立屬於自己的蛋殼雕刻三維模型，然而由於這些軟體的操作往往依賴使用者對於三維建模的背景知識以及軟體工具的熟悉程度，如何使三維建模的過程變得簡易也是一個熱門的議題。
本篇論文提出一個簡易製作出具有艾薛爾藝術風格圖效果的蛋殼雕刻模型系統架構，透過艾薛爾藝術圖的生成以及影像的後處理，產生出可貼在蛋殼模型上之二值貼圖，並依據貼圖上二值顏色的資訊來決定要在模型上切割的部分。相較一般在三維建模軟體中對模型表面做挖洞需要經過費時且不直覺的網格(mesh)調整，我們提出一種透過貼圖的方式，並且自動選擇輸入貼圖中要保留以及要捨棄的部分達到模型表面自動挖洞(auto carving)的效果，使用者可以透過這種方式快速達到想要的結果。

Egg Carving Art is a type of folk handmade artwork formed by engraving on the eggshells of birds. There are many ways of carving: painting, bas relief, yin yang and hollow carving There are also egg sculptures made by combining different carving methods. The production process of eggshell carving art usually requires several main steps. First, we need to drill a hole in the top or bottom of the egg, and then pour out the egg liquid and egg yolk inside the egg. After rinsing the hollow eggshell, we use a pencil or other drawing tool to paint on the surface of the eggshell according to the sketch. Finally we use various electric grinder carving tools to cut or polish the eggshell surface according to the painting.
Although arbitrary painting or patterns can be carved on the surface of eggshells, our research focuses on one of the art style: Escher tessellation, which works by closely fitting patterns of different shapes and repeating tiles. Forming patterns with geometric and mathematical meanings on the plane, and fusing the effect of perception illusion to make the graphics full of complex and fantastic deformation structures.
Compared with the difficulty of making eggshell carving art in reality, there are many convenient 3D model modeling software in computers nowadays. Users can use the software to create their own eggshell carving 3D models. However, the operation of these software often require user to take a lot of practice. User also need some background knowledge of 3D modeling and familiarity with software tools. Therefore how to make the process of 3D modeling easier is also a popular topic.
This paper proposes an intuitive system of eggshell sculpture modeling with the effect of Escher art style carving. Through the generation of Escher art tessellation and post-processing of the image, a binary image texture can be affixed to the eggshell model. We can then determine which part to be cut on the model based on the binary color information on the image texture. Compared to the usual time-consuming and unintuitive mesh adjustments required to dig holes on the surface of the model in 3D modeling software, we propose a method using texture mapping and automatically select the parts of the input texture to be retained or discarded. To achieve the effect of auto carving on the surface of the model, the user can quickly achieve the desired result in this way.

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