static glTF_KHR_texture_transform Deserialize(JsonNode json)
{
var t = new glTF_KHR_texture_transform();
if (json.Value.ValueType == ValueNodeType.Object)
{
foreach (var kv in json.ObjectItems())
{
var key = kv.Key.GetString();
switch (key)
{
case nameof(offset):
t.offset = DeserializeFloat2(kv.Value).ToArray();
break;
case nameof(rotation):
t.rotation = kv.Value.GetSingle();
break;
case nameof(scale):
t.scale = DeserializeFloat2(kv.Value).ToArray();
break;
case nameof(texCoord):
t.texCoord = kv.Value.GetInt32();
break;
default:
throw new NotImplementedException();
}
}
}
return(t);
}
public static bool TryGet(glTFTextureInfo info, out glTF_KHR_texture_transform t)
{
if (info != null && info.extensions is glTFExtensionImport imported)
{
foreach (var kv in imported.ObjectItems())
{
if (kv.Key.GetUtf8String() == ExtensionNameUt8)
{
t = Deserialize(kv.Value);
return(true);
}
}
}
t = default;
return(false);
}
public static (Vector2, Vector2) GetTextureOffsetAndScale(glTF_KHR_texture_transform textureTransform)
{
var offset = new Vector2(0, 0);
var scale = new Vector2(1, 1);
if (textureTransform != null)
{
if (textureTransform.offset != null && textureTransform.offset.Length == 2)
{
offset = new Vector2(textureTransform.offset[0], textureTransform.offset[1]);
}
if (textureTransform.scale != null && textureTransform.scale.Length == 2)
{
scale = new Vector2(textureTransform.scale[0], textureTransform.scale[1]);
}
// UV Coordinate Conversion: glTF(top-left origin) to Unity(bottom-left origin)
// Formula: https://github.com/vrm-c/UniVRM/issues/930
offset.y = 1.0f - offset.y - scale.y;
}
return(offset, scale);
}
