Functions
void	calculate_tangents (Span< float3 > positions, bool is_cyclic, MutableSpan< float3 > tangents)
void	calculate_normals_minimum (Span< float3 > tangents, bool cyclic, MutableSpan< float3 > normals)
void	calculate_normals_z_up (Span< float3 > tangents, MutableSpan< float3 > normals)
static bool	delta_dir (const float3 &pos, const float3 &next, float3 &r_delta_dir)
static float3	direction_bisect (const float3 &pos, const float3 &next, float3 &other_dir, bool &is_equal)
static float3	calculate_next_normal (const float3 &last_normal, const float3 &last_tangent, const float3 &current_tangent)

Function Documentation

◆ calculate_next_normal()

float3 blender::bke::curves::poly::calculate_next_normal	(	const float3 &	last_normal,
		const float3 &	last_tangent,
		const float3 &	current_tangent )

static

Rotate the last normal in the same way the tangent has been rotated.

Definition at line 146 of file curve_poly.cc.

References angle(), angle_normalized_v3v3(), blender::math::cross(), blender::math::is_zero(), LIKELY, blender::math::normalize(), and blender::math::rotate_direction_around_axis().

Referenced by calculate_normals_minimum().

◆ calculate_normals_minimum()

void blender::bke::curves::poly::calculate_normals_minimum	(	Span< float3 >	tangents,
		bool	cyclic,
		MutableSpan< float3 >	normals )

Calculate directions perpendicular to the tangent at every point by rotating an arbitrary starting vector by the same rotation of each tangent. If the curve is cyclic, propagate a correction through the entire to make sure the first and last normal align.

Definition at line 166 of file curve_poly.cc.

References angle(), angle_signed_on_axis_v3v3_v3(), BLI_assert, calculate_next_normal(), fabs(), blender::Span< T >::first(), i, blender::math::is_zero(), blender::Span< T >::last(), M_PI, blender::math::normalize(), normals, blender::math::rotate_direction_around_axis(), blender::Span< T >::size(), and UNLIKELY.

Referenced by blender::bke::CurvesGeometry::evaluated_normals().

◆ calculate_normals_z_up()

void blender::bke::curves::poly::calculate_normals_z_up	(	Span< float3 >	tangents,
		MutableSpan< float3 >	normals )

Calculate a vector perpendicular to every tangent on the X-Y plane (unless the tangent is vertical, in that case use the X direction).

Definition at line 126 of file curve_poly.cc.

References BLI_assert, i, blender::math::normalize(), normals, and blender::Span< T >::size().

Referenced by blender::bke::CurvesGeometry::evaluated_normals().

◆ calculate_tangents()

void blender::bke::curves::poly::calculate_tangents	(	Span< float3 >	positions,
		bool	is_cyclic,
		MutableSpan< float3 >	tangents )

Calculate the direction at every point, defined as the normalized average of the two neighboring segments (and if non-cyclic, the direction of the first and last segments). This is different than evaluating the derivative of the basis functions for curve types like NURBS, Bezier, or Catmull Rom, though the results may be similar.

Definition at line 74 of file curve_poly.cc.

References BLI_assert, delta_dir(), direction_bisect(), blender::IndexRange::drop_back(), blender::IndexRange::drop_front(), blender::MutableSpan< T >::fill(), blender::MutableSpan< T >::first(), blender::Span< T >::first(), i, blender::Span< T >::index_range(), is_cyclic(), blender::Span< T >::is_empty(), blender::MutableSpan< T >::last(), blender::Span< T >::last(), blender::MutableSpan< T >::size(), blender::Span< T >::size(), and blender::MutableSpan< T >::slice().