public static MeshGpuInstancing WithInstanceCustomAccessor(this MeshGpuInstancing instancing, string attribute, IReadOnlyList <Object> values)
{
Guard.NotNullOrEmpty(attribute, nameof(attribute));
attribute = attribute.ToUpperInvariant();
var expectedType = values.Where(item => item != null).FirstOrDefault()?.GetType();
if (expectedType == null)
{
return(instancing);
}
if (expectedType == typeof(int))
{
var xValues = values.Select(item => item is int val ? val : 0).ToList();
return(instancing.WithInstanceAccessor(attribute, xValues));
}
if (expectedType == typeof(Single))
{
var xValues = values.Select(item => item is float val ? val : 0).ToList();
return(instancing.WithInstanceAccessor(attribute, xValues));
}
throw new ArgumentException(expectedType.Name);
}
public static MeshGpuInstancing WithInstanceAccessors(this MeshGpuInstancing instancing, IReadOnlyList <Transforms.AffineTransform> transforms)
{
Guard.NotNull(instancing, nameof(instancing));
Guard.NotNull(transforms, nameof(transforms));
var xfrms = transforms.Select(item => item.GetDecomposed());
var hasS = xfrms.Any(item => item.Scale != Vector3.One);
var hasR = xfrms.Any(item => item.Rotation != Quaternion.Identity);
var hasT = xfrms.Any(item => item.Translation != Vector3.Zero);
if (hasS)
{
instancing.WithInstanceAccessor("SCALE", xfrms.Select(item => item.Scale).ToList());
}
if (hasR)
{
instancing.WithInstanceAccessor("ROTATION", xfrms.Select(item => item.Rotation).ToList());
}
if (hasT)
{
instancing.WithInstanceAccessor("TRANSLATION", xfrms.Select(item => item.Translation).ToList());
}
return(instancing);
}
public static MeshGpuInstancing WithInstanceCustomAccessors(this MeshGpuInstancing instancing, IReadOnlyList <IO.JsonContent> extras)
{
Guard.NotNull(instancing, nameof(instancing));
// gather attribute keys
var keys = extras
.Select(item => item.Content)
.OfType <IReadOnlyDictionary <string, Object> >()
.SelectMany(item => item.Keys)
.Distinct()
.Where(item => item.StartsWith("_", StringComparison.Ordinal));
foreach (var key in keys)
{
Object valueGetter(IO.JsonContent extra)
{
if (!(extra.Content is IReadOnlyDictionary <string, Object> dict))
{
return(null);
}
return(dict.TryGetValue(key, out var val) ? val : null);
}
var values = extras.Select(valueGetter).ToList();
instancing.WithInstanceCustomAccessor(key, values);
}
return(instancing);
}
public static unsafe MeshGpuInstancing WithInstanceAccessor <T>(this MeshGpuInstancing instancing, string attribute, IReadOnlyList <T> values)
where T : unmanaged
{
Guard.NotNull(instancing, nameof(instancing));
Guard.NotNull(values, nameof(values));
var root = instancing.LogicalParent.LogicalParent;
var view = root.CreateBufferView(values);
var accessor = root.CreateAccessor();
if (typeof(T) == typeof(int))
{
accessor.SetIndexData(view, 0, values.Count, IndexEncodingType.UNSIGNED_INT);
}
else
{
var dt = DimensionType.CUSTOM;
if (typeof(T) == typeof(Single))
{
dt = DimensionType.SCALAR;
}
if (typeof(T) == typeof(Vector2))
{
dt = DimensionType.VEC2;
}
if (typeof(T) == typeof(Vector3))
{
dt = DimensionType.VEC3;
}
if (typeof(T) == typeof(Vector4))
{
dt = DimensionType.VEC4;
}
if (typeof(T) == typeof(Quaternion))
{
dt = DimensionType.VEC4;
}
if (typeof(T) == typeof(Matrix4x4))
{
dt = DimensionType.MAT4;
}
if (dt == DimensionType.CUSTOM)
{
throw new ArgumentException(typeof(T).Name);
}
accessor.SetVertexData(view, 0, values.Count, dt, EncodingType.FLOAT, false);
}
instancing.SetAccessor(attribute, accessor);
return(instancing);
}
public MeshGpuInstancing UseGpuInstancing()
{
var ext = GetGpuInstancing();
if (ext == null)
{
ext = new MeshGpuInstancing(this);
this.SetExtension(ext);
}
return(ext);
}
