cgltf-cr

Crystal bindings CGltf

Installation

1. Add the dependency to your shard.yml:

   dependencies:
     cgltf:
       github: guidipolito/cgltf-cr
   

2. Run shards install

Usage

require "cgltf"

filepath = "./src/example/test3.glb"
obj = Cgltf.load_file(filepath)
primitive = obj.meshes.first.primitives.first
p primitive.positions.not_nil! # Print vertice positions
p primitive.normals.not_nil! # print vertice normals
p primitive.texcoords(0) # print UVs

example making an array for a Vertex Buffer Object

  pri = obj.meshes.first.primitives.first
  positions = pri.positions.not_nil!.map(&.to_f32).each_slice(3).to_a  # make an array of vertices [ [x, y, z] ...]
  normals = pri.normals.not_nil!.map(&.to_f32).each_slice(3).to_a # same thing for normals
  uv = pri.texcoords(0).not_nil!.map(&.to_f32).each_slice(2).to_a # uvs [ [x, y], [x, y]]

  vertices = [] of Float32
  (0...positions.size).each do |i|
    vertices << positions[i][0]
    vertices << positions[i][1]
    vertices << positions[i][2]
    vertices << normals[i][0]
    vertices << normals[i][1]
    vertices << normals[i][2]
    vertices << uv[i][0]
    vertices << uv[i][1]
  end
  
  # vertice array for passing to opengl with [ px, py, pz, nx, ny, nz, uvx, uvy]

Contributing

1. Fork it (https://github.com/guidipolito/cgltf-cr/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• guidipolito - creator and maintainer