ReinterpretedTexture_rendering

This is a web prototype system about a vector point symbol rendering method based on the texture structure. The rendering context is WebGL2, and the base map is presented by Mapbox GL js. A texel in the texture is a piece of vertex information in the size of 4 Bytes. It contains a pair of coordinates and a color index of one of the vertex of a vector point symbol (organized by one triangle strip). GPU Instancing is used to launch the rendering pipeline. All different symbols can be rendered in one draw call by specifying their layout information about where they lie in the texture. With the help of the built-in variable gl_VertexID and textures' random access feature, vertices can be decoded from the symbol texture. By using thie method, both the quality of the vector style and the performance of the raster style can be taken to improve the point symbol drawing on maps.</p

ReinterpretedTexture_Prototype

This is a web prototype system about a vector point symbol rendering method based on the texture structure. The rendering context is WebGL2, and the base map is presented by Mapbox GL js. A texel in the texture is a piece of vertex information in the size of 4 Bytes. It contains a pair of coordinates and a color index of one of the vertex of a vector point symbol (organized by one triangle strip). GPU Instancing is used to launch the rendering pipeline. All different symbols can be rendered in one draw call by specifying their layout information about where they lie in the texture. With the help of the built-in variable gl_VertexID and textures' random access feature, vertices can be decoded from the symbol texture. By using thie method, both the quality of the vector style and the performance of the raster style can be taken to improve the point symbol drawing on maps.</p

A reinterpreted-texture strategy for rendering point symbols based on graphics processing unit

The increasing demands of presenting large numbers of points in maps have promoted the progress of rendering point symbols in GPUs. Although the drawing efficiency issue can be handled with texture mapping methods, the rendering quality problem due to the fixed resolution that affects map renders’ visual experiences remains. The method of directly drawing vector paths of a point symbol can be used to satisfy the sharper effect of point symbols. However, it requires high memory cost and affects the drawing efficiency. This paper proposes a point symbol rendering method using the idea of reinterpreted textures. The rendering data used in this method are based on vectors to achieve refined results. Vector properties of symbols are encoded and organized into the texture structure with specific layout schemes. In the rendering phase, an instanced pipeline is launched to accept the texture and decode the required attributes. The proposed method takes advantage of fast access and continuity of textures while retaining geometric transformations. These features allow all symbols to be drawn in one single draw call and rotated or scaled arbitrarily. Experiments on drawing quality and efficiency demonstrate that the proposed method achieves fast and stable performance while maintaining the rendering quality.</p

Customizable process design for collaborative geographic analysis

Collaborative geographic analysis can lead to better outcomes but requires complicated interactions among participants, support resources and analytic tools. A process expression with explicit structure and content can help coordinate and guide these interactions. For different geographic problems, the structure and content of collaborative geographic analysis are generally distinct. Since the process structure embodies the pathway of problem-solving and the process content contains the information flow and internal interactions, both the structure and the content of the process expression must be clarified during process customization. However, relevant studies concerning the collaborative geographic analysis process mainly focus on the process structure, which remains a “black box” in terms of the process content, especially the internal interactions. Therefore, this article designs a customizable process expression model that takes both process structure and content into account and proposes a corresponding process customization method for collaborative geographic analysis. Additionally, a support method for geographic analysis process implementation is also provided. To verify the feasibility and capability, these methods were implemented in a prototype system, and a case study on traffic noise assessment was conducted. The results suggest that the proposed strategy can effectively improve geographic analysis by customizing processes, guiding participants, performing interactions, and recording operations throughout the process.</p