from panda3d.core import ParametricCurve
- class ParametricCurve
A virtual base class for parametric curves. This encapsulates all curves in 3-d space defined for a single parameter t in the range [0,get_max_t()].
- adjust_point(t: float, px: float, py: float, pz: float) bool
Recomputes the curve such that it passes through the point (px, py, pz) at time t, but keeps the same tangent value at that point.
- adjust_pt(t: float, px: float, py: float, pz: float, tx: float, ty: float, tz: float) bool
Recomputes the curve such that it passes through the point (px, py, pz) with the tangent (tx, ty, tz).
- adjust_tangent(t: float, tx: float, ty: float, tz: float) bool
Recomputes the curve such that it has the tangent (tx, ty, tz) at time t, but keeps the same position at the point.
- calc_length(from: float, to: float) float
Approximates the length of the curve segment from parametric time ‘from’ to time ‘to’.
- find_length(start_t: float, length_offset: float) float
Returns the parametric value corresponding to the indicated distance along the curve from the starting parametric value.
This is the inverse of calc_length(): rather than determining the length along the curve between two parametric points, it determines the position in parametric time of a point n units along the curve.
The search distance must not be negative.
- get_curve_type() int
Returns the flag indicating the use to which the curve is intended to be put.
- get_max_t() float
Returns the upper bound of t for the entire curve. The curve is defined in the range 0.0f <= t <= get_max_t(). This base class function always returns 1.0f; derived classes might override this to return something else.
- get_num_dimensions() int
Returns the number of significant dimensions in the curve’s vertices, as set by a previous call to
set_num_dimensions(). This is only a hint as to how the curve is intended to be used; the actual number of dimensions of any curve is always three.
- is_valid() bool
Returns true if the curve is defined. This base class function always returns true; derived classes might override this to sometimes return false.
- recompute() bool
Recalculates the curve, if necessary. Returns true if the resulting curve is valid, false otherwise.
- set_curve_type(type: int)
Sets the flag indicating the use to which the curve is intended to be put. This flag is optional and only serves to provide a hint to the egg reader and writer code; it has no effect on the curve’s behavior.
Setting the curve type also sets the num_dimensions to 3 or 1 according to the type.
THis flag may have one of the values PCT_XYZ, PCT_HPR, or PCT_T.
- set_num_dimensions(num: int)
Specifies the number of significant dimensions in the curve’s vertices. This should be one of 1, 2, or 3. Normally, XYZ and HPR curves have three dimensions; time curves should always have one dimension. This only serves as a hint to the mopath editor, and also controls how the curve is written out.
- stitch(a: ParametricCurve, b: ParametricCurve) bool
Regenerates this curve as one long curve: the first curve connected end-to- end with the second one. Either a or b may be the same as ‘this’.
Returns true if successful, false on failure or if the curve type does not support stitching.
- write_egg(filename: Filename, cs: CoordinateSystem) bool
Writes an egg description of the nurbs curve to the specified output file. Returns true if the file is successfully written.