Commit Graph

8 Commits

Author SHA1 Message Date
Johnny Matthews
231948f33f Splines: Add a method for reversing a Spline
This moved the spline reversing logic out of the Curve Reverse geometry
node and into the spline class. This allows a spline to reverse itself
with a call to `my_spline.reverse()`

The base class will reverse position, radii & tilt, while specialized
versions are created for Bezier and Nurbs splines to reverse the
additional data that these classes encapsulate.

Differential Revision: https://developer.blender.org/D12501
2021-09-15 13:57:01 -05:00
Hans Goudey
f3eecfe386 Cleanup: Refactor spline copying functions
Make the virtual functions protected and simpler, so that the logic is
better contained in the base class's implementation. Also introduce a
`copy_without_attributes` method to be used for realizing instances.
2021-06-22 11:32:50 -05:00
Hans Goudey
dc3b7602ee Cleanup: Rename variables, use shorter names
`src` and `dst` are perfectly clear, and avoid repeating unecessary
characters when writing the variables many times, allowing more space
for everything else.
2021-06-21 23:02:00 -05:00
Hans Goudey
feb6fd632f Cleanup: Rename spline interpolation functions
The names were slightly longer than they needed to be clear,
and when they are shorter they tend to fit on one line better.
2021-06-20 22:05:57 -05:00
Hans Goudey
21de669141 Splines: Function to copy spline settings without data
Often you need to copy a spline to do an operation, but don't want
to manually copy over all of the settings. I've already forgotten to
do it once anyway. These functions copy a spline's "settings" into a
new spline, but not the data. I tried to avoid duplicating any copying
so this is easier to extend in the future.

Differential Revision: https://developer.blender.org/D11463
2021-06-02 09:11:35 -04:00
Hans Goudey
627f357127 Geometry Nodes: Support for dynamic attributes on curve splines
With this patch you will be able to add and remove attributes from curve
data inside of geometry nodes. The following is currently implemented:
* Adding attributes with any data type to splines or spline points.
* Support for working with multiple splines at the same time.
* Interaction with the three builtin point attributes.
* Resampling attributes in the resample node.

The following is not implemented in this patch:
* Joining attributes when joining splines with the join geometry node.
* Domain interpolation between spline and point domains.
* More efficient ways to call attribute operations once per spline.

Differential Revision: https://developer.blender.org/D11251
2021-05-19 13:22:09 -04:00
Hans Goudey
3185084efb Geometry Noes: Curve Resample Node
This node generates a naturally parametarized (even length edge) poly
spline version of every spline in the input. There are two modes,
"Count", and "Length". These are similar to the same options for the
line primitive node in end points mode.

I implemented this instead of a "Sample Points" node, because for this
operation it's trivial to keep the result as a curve, which is nice
since it increases flexibility, and because it can make instancing
simpler, i.e. using the transforms of each evaluated point rather than
requiring the construction of a "rotation" attribute.

Differential Revision: https://developer.blender.org/D11173
2021-05-07 15:37:06 -05:00
Hans Goudey
8216b759e9 Geometry Nodes: Initial basic curve data support
This patch adds initial curve support to geometry nodes. Currently
there is only one node available, the "Curve to Mesh" node, T87428.

However, the aim of the changes here is larger than just supporting
curve data in nodes-- it also uses the opportunity to add better spline
data structures, intended to replace the existing curve evaluation code.
The curve code in Blender is quite old, and it's generally regarded as
some of the messiest, hardest-to-understand code as well. The classes
in `BKE_spline.hh` aim to be faster, more extensible, and much more
easily understandable. Further explanation can be found in comments in
that file.

Initial builtin spline attributes are supported-- reading and writing
from the `cyclic` and `resolution` attributes works with any of the
attribute nodes. Also, only Z-up normal calculation is implemented
at the moment, and tilts do not apply yet.

**Limitations**
 - For now, you must bring curves into the node tree with an "Object
   Info" node. Changes to the curve modifier stack will come later.
 - Converting to a mesh is necessary to visualize the curve data.

Further progress can be tracked in: T87245
Higher level design document: https://wiki.blender.org/wiki/Modules/Physics_Nodes/Projects/EverythingNodes/CurveNodes

Differential Revision: https://developer.blender.org/D11091
2021-05-03 12:29:17 -05:00