Mesh files

In PewPew Live, a mesh is a collection of lines in 3D.

To create a mesh, you need to list the coordinates of the points making up the model, and how the points are linked. Lua scripts describing meshes needs to create a table called meshes. That table must contain one or more meshes.

Example of a file that defines two meshes:

meshes = {
  { -- A 500x500 square
    vertexes = {{0,0,0}, {500,0,0}, {500,500,0}, {0,500,0}},
    colors = {0xffffffff, 0xffff00ff, 0xff00ffff, 0xff0000ff},
    segments = {{0,1,2,3,0}}
  },
  { -- A right-angled triangle
    vertexes = {{0,0,0}, {500,0,0}, {0,500,0}},
    colors = {0xffff00ff, 0xff00ffff, 0xff0000ff},
    segments = {{0,1,2,0}}
  }
}

Vertexes

The vertexes field contains the list of vertexes. Vertexes are represented by three numbers. Those numbers can be floating point numbers.

Segments chains

The segment field describes which vertexes should be joined by a segment. It contain a list of segment chains. Each segment chain is a table that holds a lists of 0-based indexes to vertexes that should be connected by a segment.

Important: There is a difference between segments = {{0,1}, {1,2}} and segments = {{0,1,2}}. In the first case, 2 separate segments will be generated. In the second case, two segments linked with a miter join will be generated.

Colors

The optional colors field contains the colors of each vertexes. If the colors field is present, it must contain as many colors as there are vertexes. Colors are 32 bit RGBA values.

0xff0000ff -- opaque red
0xff000080 -- slightly transparent red
0xff000000 -- fully transparent red

Note that all meshes are rendered with additive blending.

Procedural rendering

Astute readers may have realized that because meshes is described in a Lua script, it can be generated at runtime. See for instance this example.

This is the prefered way of creating complex meshes, as it is both more efficient and more consistent with the rest of the game.