- r -
- radius
: _GradientInfo
- random_info
: _CacheInfo
, _FxInfo
- raw
: _MagickInfo
- reason
: _ExceptionInfo
- red
: _Cluster
, _ColorMapInfo
, _DoublePixelPacket
, _LongPixelPacket
, _MagickPixelPacket
, _PixelPacket
, _QuantumPixelPacket
, _RealPixelPacket
- red_primary
: _ChromaticityInfo
- reference_count
: _BlobInfo
, _CacheInfo
, _Image
, SemaphoreInfo
- region
: _NexusInfo
- register_module
: _ModuleInfo
- relinquish
: _ExceptionInfo
- relinquish_key
: _HashmapInfo
, _SplayTreeInfo
- relinquish_value
: _HashmapInfo
, _SplayTreeInfo
- remainder
: _MagickModulo
- render
: _DrawInfo
- rendering_intent
: _Image
- reservoir
: _RandomInfo
- resize_memory_handler
: _MagickMemoryMethods
- rho
: _GeometryInfo
- right
: _ExtentPacket
, _IntervalTree
, _NodeInfo
- rights
: _PolicyInfo
, _PolicyMapInfo
- root
: _CubeInfo
, _SplayTreeInfo
, _XMLTreeRoot
- rows
: _CacheInfo
, _Image
, _MatrixInfo
- rx
: _AffineMatrix
- ry
: _AffineMatrix