Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Texture
HATCHINGSHADER_TEXTURE
Parameter: Tile UV
HATCHINGSHADER_TILE
Parameter: Rotational UV
HATCHINGSHADER_ROTATIONAL
Parameter: Scale
HATCHINGSHADER_SCALE
Parameter: Rotate UV
HATCHINGSHADER_ROTATE
Parameter: Offset U
HATCHINGSHADER_OFFSET_U
Parameter: Offset V
HATCHINGSHADER_OFFSET_V
Parameter: Density
HATCHINGSHADER_DENSITY
Parameter: Density U
HATCHINGSHADER_DENSITY_U
Parameter: Density V
HATCHINGSHADER_DENSITY_V
Parameter: Scatter U
HATCHINGSHADER_SCATTER_U
Parameter: Scatter V
HATCHINGSHADER_SCATTER_V
Parameter: Spacing U
HATCHINGSHADER_SPACE_U
Parameter: Variation
HATCHINGSHADER_SPACE_U_VAR
Parameter: Spacing V
HATCHINGSHADER_SPACE_V
Parameter: Variation
HATCHINGSHADER_SPACE_V_VAR
Parameter: Scale U
HATCHINGSHADER_SCALE_U
Parameter: Variation
HATCHINGSHADER_SCALE_U_VAR
Parameter: Scale V
HATCHINGSHADER_SCALE_V
Parameter: Variation
HATCHINGSHADER_SCALE_V_VAR
Parameter: Rotate
HATCHINGSHADER_STOKE_ROTATE
Parameter: Crosses
HATCHINGSHADER_CROSSED
Parameter: Cross Rotation
HATCHINGSHADER_CROSS_ROTATE
Parameter: Dark Stroke Color
HATCHINGSHADER_STROKE_COLOR
Parameter: Light Stroke Color
HATCHINGSHADER_STROKELIGHT_COLOR
Parameter: Background Color
HATCHINGSHADER_BACK_COLOR
Parameter: Show Dark Strokes
HATCHINGSHADER_DARK_STROKES
Parameter: Show Light Strokes
HATCHINGSHADER_LIGHT_STROKES
Parameter: Shade Levels
HATCHINGSHADER_LEVELS
Parameter: Threshold
HATCHINGSHADER_THRESHOLD
Parameter: Shadows
HATCHINGSHADER_SHADOW
Parameter: Diffuse
HATCHINGSHADER_DIFFUSE
Parameter: Specular
HATCHINGSHADER_SPEC
Parameter: Illumination
HATCHINGSHADER_ILLUM
Parameter: Use Bump
HATCHINGSHADER_BUMP
Parameter: Camera
HATCHINGSHADER_CAMERA
Parameter: Lights
HATCHINGSHADER_LIGHTS
Parameter: Specular
HATCHINGSHADER_SPECULAR
Parameter: Illumination
HATCHINGSHADER_ILLUMINATION
Parameter: Shadow
HATCHINGSHADER_SHADOWS
Parameter: Modifies Contrast
HATCHINGSHADER_CONTRAST
Parameter: Use Lights
HATCHINGSHADER_INCEXC
Parameter: Lights
HATCHINGSHADER_INCEXC_LIGHTS