隨著人們生活改善與交通安全意識的提升，有效規劃道路和人行道來改善人行環境，已經成為許多國家對於道路設計關注的焦點之一，受益於科技的進步，現如今實景掃瞄能以高度準確的方式捕捉場景的細節和幾何形狀，為道路及地景提供準確的地勢變化與地形特徵，在道路設計過程中，能確保道路與地形的銜接，降低工程風險，並且，提供更安全和可持續的交通基礎設施，精準地形高程設計可以確使道路設計師能夠在設計過程中考慮到坡度和曲線的因素，包括確定適當的道路坡度，以提供良好的行車條件和水流排放，並且，設計合適的曲線半徑，以保證安全和舒適的行車環境。因此，本論文主要著重在配合傳統設計師習慣於編輯曲線，而非直接操作模型的使用習慣，提供簡易的方法編輯三維曲線來控制實景模型的地形高程從而達到高效且精準的高程設計，同時，透過建立和編輯鋪磚材質讓設計師得以發揮所長，建構出美觀且符合規範的道路景觀。

為了符合設計師們習慣於用二維橫斷面圖表示地型的習慣，本論文提出基於二
維橫斷面作為約束的曲面高程編輯工具，可自由地讓使用者在二維模式下使用參數化曲線繪製橫斷面作為地形高程的強約束(Hard Constraint)，透過約束得勞內三角化(Constrained Delaunay Triangulation，CDT) [1] 建構出地形高程約束，再導入多重網格方法(Multigrid Method) [2] 方法內插地形高程，去快速產生真實且平滑的可控地形。使用參數化曲線繪製橫斷面可以解決傳統地形編輯，例如，素描介面或是筆刷工具在重複編輯時，無法調整局部控制點來影響約束範圍導致調整變得複雜的問題。

利用多組二維橫斷面圖作為地形約束這種降維的操作模式，能有效解決傳統地
形編輯在三維環境中設定約束和控制困難，並且與傳統設計師依照二維設計模式的操作習慣不符，從而加深了道路設計師們的學習曲線的問題。透過約束得勞內三角化(Constrained Delaunay Triangulation，CDT) [1] 建構邊界與約束，可以滿足設計師要約束曲線直接反應在網格剖面上的需求，在三角化的範圍內均勻採樣，再透過二維高度場進行平滑，能有效過度約束曲線間網格的平滑程度，產生真實且平滑的地形。

此外，為了讓道路設計師們能建構符合道路規範而且美觀的人行道，並且，滿足設計師對於設計後的鋪面要能有效模擬實際完工結果的需求，也就是說，鋪面上貼圖的每個鋪磚大小需要依照實際鋪磚大小顯示，同時，不同鋪面的鋪磚擺放朝向也可能不同，因此，需要有簡易的編輯方式來調整擺放結果。本論文設計一鋪面編輯系統，能讓使用者自定鋪磚樣式，在鋪磚擺放上，本論文會使用最小二乘保角參數化(Least SquaresConformal Maps) 的網格參數化(Mesh Parameterization) 方法將地形網格攤平至二維平面，並且，根據地形網格定義出此地形的貼圖座標系，鋪磚會朝著座標系的右向量和上向量照著鋪磚大小依序排列。透過最小二乘保角參數化(Least Squares Conformal Maps)
的網格參數化(Mesh Parameterization) 方法能避免複雜地形攤平至二維平面造成貼圖扭曲和失真的問題，建構了貼圖座標系後，能讓使用者透過位移、旋轉地形的貼圖座標系來編輯鋪磚的擺放結果，能滿足設計師對於不同鋪面需要調整擺放朝向的需求，解決解決傳統地形編輯難以透過全局操控來控制貼圖擺放的問題。依據鋪磚實際大小縮放貼圖空間使得鋪磚會依實際大小貼合地形起伏，本論文提供三種不同的擺放方式能有效模擬鋪磚於現地擺放後的實際結果。

最後，會透過以下三個部分來驗證本論文能有效提高設計師對於道路高程設計的效率，分別為互動式曲線驗證、鋪磚貼合驗證和使用者研究。互動式曲線驗證包含了，三維曲線採樣點的投影正確性、是否滿足設計師描繪邊線的需求和效能驗證三項，來驗證本論文能提供設計師直覺且流暢的操作體驗。鋪磚貼合驗證則是會比較不同的參數化方法在不同高低起伏地形中的擺放結果，並且驗證本論文選擇的方法能有效模擬真實擺放現況。最後，透過使用者研究，讓受試者在相同的實景道路設計場景中，比較本論文提出的高程編輯流程與傳統設計流程，並且，通過過統計的方法來驗證本論文相較傳統設計流程能有效提高設計師對於道路高程設計的效率。

The accurate capture of scene details and geometric shapes through real-world scanning provides precise terrain variations and landscape features for roads and terrains. It ensures the seamless integration of roads with the surrounding topography, reduces engineering risks, and provides safer and sustainable transportation infrastructure. Precise terrain elevation design allows road designers to consider factors such as gradients and curves, including determining appropriate road slopes to provide favorable driving conditions and water flow discharge. It also facilitates the design of suitable curve radii to ensure a safe and comfortable driving environment. Furthermore, with the increase in awareness of traffic safety, effectively planning roads and sidewalks to enhance pedestrian environments has become a key focus of road design in many countries. Therefore, this paper primarily focuses on using a simple method to edit 3D curves for controlling the terrain elevation of reality-scanned models, achieving efficient and precise elevation design. Simultaneously,
by establishing and editing terrain tiling materials, designers can leverage their expertise to construct visually appealing and compliant road landscapes. Traditional road designers are usually accustomed to handling planar designs, and on plan drawings, they create longitudinal and cross-section profiles to ensure road flatness. However, in a three-dimensional space, road design involves more vertical variations, three-dimensional structures at intersections, slopes, elevation changes, and other factors. These complex spatial relationships make accurately setting constraints and controls challenging in a 3D environment. This discrepancy also deviates from the operational habits of traditional designers who are used to working with 2D design patterns, thus deepening the learning curve for road designers. Therefore, this paper introduces a surface elevation editing tool based on feature lines that
allows users to freely set feature lines as robust constraints for terrain elevation. Moreover, users can adjust line types and elevations in a two-dimensional mode to align with the operational habits of traditional designers. Additionally, users can define the influence range of control points on feature lines and introduce diffusion equations to generate gradient maps and noise maps. This process facilitates the rapid generation of realistic and smooth controllable terrains. Furthermore, to enable road designers to construct visually appealing sidewalks that adhere to road regulations, this paper introduces a pavement editing system that allows users to customize tile patterns. Similarly, to align with the designers’ practices, the system facilitates the displacement and rotation of texture coordinates for placing 3D terrain tiles from a top-down perspective, ensuring distortion-free placement. Finally, through user studies conducted in three different scenarios of large, medium, and small-scale real-world designs, participants compared this thesis’s methods with two other approaches. Statistical analysis was conducted to verify that this thesis adheres most closely to designers’ traditional habits and provides the most convenient way to create 3D elevation landscapes from 2D drawings. The other two methods were based
on NURBS surface editing and terrain brush, respectively.

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