What problem does this feature solve?

eCharts GL and 3D rendering is very restricted at the moment when wanting to visualise 3D data outside of scatter/plot or a very limited "polygon" (which is really just extruded 2D shape)

As web browsers and WebGL get more powerful, there is opportunity to visualise data in new ways in 3D.

eCharts would be improved in their 3D/GL area with the ability to have arbitrary mesh support:

Use cases:

• Medical application where complex 3D models of organs can be rendered
• Mining and other large scale (geographically) projects needing to visualise spatial data
• Arbitrary meshes as MarkPoints (a 3D human mesh, a 3D car mesh on a road, other 3D markers)
• Markpoints and Markareas as sub-meshes , think of a medical application where certain surface patches have Tooltip data

What does the proposed API look like?

In the Polygon series type ( https://echarts.apache.org/en/option-gl.html#series-polygons3D.data )
You can only set XY of the data and then a constant height for everything.

It would be great to support rich 3D mesh data, here is simple proposal of a triangle

data:[
{
vertices: [[0,0,0], [0,1,0], [0,0,1]],
triangles: [ [0,1,2] ] // Indexes of the vertex buffer with a stride of 3
uv: [[0,0], [0,0.5], [0.5,0] // UV coordinates of vertices for texture mapping
}
]

How we feed these arrays could then be arbitrary... from a proceedural process, or by processing a popular 3D file (STL, FBX, OBJ)

Generally, the mesh data could include

• Sub-meshes to denote different materials ( data:[ {meshA}, {meshB} ] )
• Multi-stream Vertex (position, normal, UV, tangent, bitangent, RGBA color)
• Tooltip support? (based on submesh? or different polygons , vertices, edges?)