syntax = "proto2";
// GF Axis Registry Protos

// An axis in the GF Axis Registry
message AxisProto {
  // Axis tag
  optional string tag = 1;

  // Display name for axis, e.g. "Optical size" for 'opsz'
  // Like 'Name' in
  // https://docs.microsoft.com/en-us/typography/opentype/spec/dvaraxistag_opsz
  optional string display_name = 7;

  // Lower bound for the axis
  optional float min_value = 2;

  // The default position to use and to prefer for exemplars
  optional float default_value = 3;

  // Upper bound for the axis
  optional float max_value = 4;

  // Input values for this axis must aligned to 10^precision
  optional int32 precision = 5;

  // Fallback positions along the axis
  repeated FallbackProto fallback = 6;

  // Short descriptive paragraph
  optional string description = 8;

  // Whether only the fallback positions should be used, for example, an axis
  // might have only three relevant positions: the min, the middle, and the max.
  optional bool fallback_only = 9;

  // Next = 10
}

message FallbackProto {
  optional string name = 1;
  optional float value = 2;
  optional string display_name = 3;
}