private MapChunkData _initChunkBuffers(IMapGrid grid, IMapChunk chunk)
{
var vao = (uint)GL.GenVertexArray();
GL.BindVertexArray(vao);
var vboSize = _verticesPerChunk(chunk) * Vertex2D.SizeOf;
var eboSize = _indicesPerChunk(chunk) * sizeof(ushort);
var vbo = new GLBuffer(this, BufferTarget.ArrayBuffer, BufferUsageHint.DynamicDraw,
vboSize, $"Grid {grid.Index} chunk {chunk.Indices} VBO");
var ebo = new GLBuffer(this, BufferTarget.ElementArrayBuffer, BufferUsageHint.DynamicDraw,
eboSize, $"Grid {grid.Index} chunk {chunk.Indices} EBO");
ObjectLabelMaybe(ObjectLabelIdentifier.VertexArray, vao, $"Grid {grid.Index} chunk {chunk.Indices} VAO");
// Vertex Coords
GL.VertexAttribPointer(0, 2, VertexAttribPointerType.Float, false, Vertex2D.SizeOf, 0);
GL.EnableVertexAttribArray(0);
// Texture Coords.
GL.VertexAttribPointer(1, 2, VertexAttribPointerType.Float, false, Vertex2D.SizeOf, 2 * sizeof(float));
GL.EnableVertexAttribArray(1);
// Assign VBO and EBO to VAO.
// OpenGL 3.x is such a good API.
vbo.Use();
ebo.Use();
var datum = new MapChunkData(vao, vbo, ebo)
{
Dirty = true
};
_mapChunkData[grid.Index].Add(chunk.Indices, datum);
return(datum);
}