Wang Qinmin

Geometrical shapes and swaying movements of realistic tree: design and implementation

Trees and plants are important elements of outdoor scenes, therefore, it makes demands of research involved in computer graphics on methods to realize the natural-looking trees and plants in various environmental condition, such as windy or stormy weather, to contribute more facticity to the virtual reality. The paper starts from introducing the general background. Then, an approach adopting a series of statistical curves as inputted parameters of tree morphogenesis and motion depiction, which represent ramification modes, phyllotaxes or motion profiles of leaves and stems. Finally, some experimental models in virtual scene were showed. We focus on the faithful morphogenesis of tree, swaying motion in wind and the appropriate rendering speed. Aside, all the inputted statistical curves can be modified interactively to integrate the research work of botanists and other experts, which vary with species and districts. Within this methodology, various plant models can be created easily and rapidly without any botanic background, and faithful motion of tree in wind can be simulated easily with proper engineering accuracy and effective computation.Trees and plants are important elements of outdoor scenes, therefore, it makes demands of research involved in computer graphics on methods to realize the natural-looking trees and plants in various environmental condition, such as windy or stormy weather, to contribute more facticity to the virtual reality. The paper starts from introducing the general background. Then, an approach adopting a series of statistical curves as inputted parameters of tree morphogenesis and motion depiction, which represent ramification modes, phyllotaxes or motion profiles of leaves and stems. Finally, some experimental models in virtual scene were showed. We focus on the faithful morphogenesis of tree, swaying motion in wind and the appropriate rendering speed. Aside, all the inputted statistical curves can be modified interactively to integrate the research work of botanists and other experts, which vary with species and districts. Within this methodology, various plant models can be created easily and rapidly without any botanic background, and faithful motion of tree in wind can be simulated easily with proper engineering accuracy and effective computation.

Interactive Physical Based Animation of Tree Swaying in Wind

Lots of researches have been done on computer animation of tree swaying in wind. Some of them employed artificial simplification methods which could not achieve faithful swaying motion, others adopted complicated physical principles which would involve vast computation and fail to get an appropriate rendering speed. This paper presents a series of convenient interactive physical based methods for animation of trees swaying in wind. We focus on both the faithful swaying motion and the appropriate rendering speed. Therefore, a lot of statistical curves, representing wind profile loaded in tree or stem displacement profile and so on, are introduced for swaying motion calculation. All those curves can be modified interactively to get best match with the researches of botanists and other experts. These methods can be adjusted quickly and conveniently to simulate the animation of faithful tree swaying in wind with proper engineering accuracy and effective computation.

Study on GML and SVG-based Open WebGIS and its application

In this paper, GML and SVG are discussed firstly, especially in the role of open WebGIS. Then an open WebGIS framework is put forward that using GML to store and integrate geographic spatial data and using SVG to implement Web display and operation for geographic spatial data. In the end, taking a forestry data as an example, an open WebGIS application system was set up and discussed.

WebGIS-based surface 3D reconstruction of pipeline

In this paper, the method of triangles slice construction was presented for reconstructing 3D pipeline surface. In this means, shape points were calculated by surface outline equation which was got from quadratic surface. Then these shape points were patched with triangles grid to constructed triangles slice, which gained the pipeline surface model. Finally, the pipeline models were rendered by means of computer graphics in order to implement 3D pipeline surface reconstruction. In the end, a reconstruction instance was given.

Suitability evaluation of fruit trees in Fujian southern mountain areas based on DEM and GIS using a multi-criteria evaluation approach

The application of a multicriteria evaluation (MCE) approach to identify suitable areas for the production of banana, lichee and longyan in Southeast of Fujian Province in China is presented. Climate, terrain and soil databases were used to integrate GIS coverage. Because of the varied topography of Fujian province, the yearly average temperature and minimum temperature were modeled through DEM for the whole region. The evaluation factors of slope, aspect were derived from DEM through ARCGIS8.3 software. Relevant criteria for this fruit trees and suitability levels were defined. This information was used to obtain the criteria maps, which in turn were used as input into the MCE algorithm. Using weighted linear combination with the GIS data layers, a certain suitability map could be produced. Landsat TM images in the autumn of 1998 were processed using ERDAS Image8.5 software by means of a supervised classification to obtain a land use/cover map. These land use/cover and the suitability maps were crossing to identify differences and similarities between the present land use and the suitable areas for banana, lichee and longyan.

Monitoring wetland change of Xianghai nature reserve using Landsat TM data

Zhang Hongyan Lu Xuejun Wang Qinmin Li Huiguo ( 1 Key Laboratory of Wetland Ecology and Vegetation Restoration for National Environmental Protection, Northeast Normal University, Changchun 130024, China ) ( 2 Institute of Geographical Sciences and Natural Resources Research, State Key Laboratory of Resources and Environmental Information System, Beijing 100101, China ) ( 3 Fuzhou University, Fuzhou 350002, China )