A Study Of The 3D Plant Modeling Base Sketch

Sketch is a simple and rapid method which can reflect the assumption of the object model, record and capture the inspiration and conception of the designer. Recently sketch-based modeling has combined sketch with a 3D technology advantage. This has become a hot topic for many scientific research institutes and universities.First, this paper describes the development status of sketch-based modeling. Next it introduces the basic theory, arithmetic and the key technique. Finally, a thorough study of the 3D plant modeling base sketch is conducted.After analyzing, then summarizing the features of the tree's contour, a method is proposed. First, the main trunk is sketched, this determines the basic contour. Then the more fine branches that are of similar shapes are automatically generated from the main trunk. From this example, the 3D tree modeling based sketch system is developed.According to the analysis of the sketch flower feature, a method is proposed that the 3D flower model be constructed using 2D sketch. Then the system of 3D flower modeling is developed. The flower model is established by using the interface to ketch the flower's strokes, identify and analyze its features, curve surface construction, space and position estimation, and how to treat unreasonable strokes.The main methods are as follows:According to the branch feature, the 3D fractal algorithm is proposed for the tree branch sketch.Combined with the sketch flower stroke feature, an algorithm is proposed which is used to re-determine the sequence of the points on the curve, compute the flower's center, classify the sketch curve of the same petal, identify the silhouette, etc. According to the petal shape feature, the petal's shape can be constructed from the cross section curve, and the given parameter formula.From the analysis of the petal contour line sketch, the projection geometry model is established, and the position and angle of the cross section are computed in the 3D space.