Graphite/node-graph/gcore/src/subpath/transform.rs

63 lines
2.2 KiB
Rust

use super::structs::Identifier;
use super::*;
use glam::{DAffine2, DVec2};
/// Functionality that transforms Subpaths, such as split, reduce, offset, etc.
impl<PointId: Identifier> Subpath<PointId> {
/// Returns [ManipulatorGroup]s with a reversed winding order.
fn reverse_manipulator_groups(manipulator_groups: &[ManipulatorGroup<PointId>]) -> Vec<ManipulatorGroup<PointId>> {
manipulator_groups
.iter()
.rev()
.map(|group| ManipulatorGroup {
anchor: group.anchor,
in_handle: group.out_handle,
out_handle: group.in_handle,
id: PointId::new(),
})
.collect::<Vec<ManipulatorGroup<PointId>>>()
}
/// Returns a [Subpath] with a reversed winding order.
/// Note that a reversed closed subpath will start on the same manipulator group and simply wind the other direction
pub fn reverse(&self) -> Subpath<PointId> {
let mut reversed = Subpath::reverse_manipulator_groups(self.manipulator_groups());
if self.closed {
reversed.rotate_right(1);
};
Subpath {
manipulator_groups: reversed,
closed: self.closed,
}
}
/// Apply a transformation to all of the [ManipulatorGroup]s in the [Subpath].
pub fn apply_transform(&mut self, affine_transform: DAffine2) {
for manipulator_group in &mut self.manipulator_groups {
manipulator_group.apply_transform(affine_transform);
}
}
/// Returns a subpath that results from rotating this subpath around the origin by the given angle (in radians).
pub fn rotate(&self, angle: f64) -> Subpath<PointId> {
let mut rotated_subpath = self.clone();
let affine_transform: DAffine2 = DAffine2::from_angle(angle);
rotated_subpath.apply_transform(affine_transform);
rotated_subpath
}
/// Returns a subpath that results from rotating this subpath around the provided point by the given angle (in radians).
pub fn rotate_about_point(&self, angle: f64, pivot: DVec2) -> Subpath<PointId> {
// Translate before and after the rotation to account for the pivot
let translate: DAffine2 = DAffine2::from_translation(pivot);
let rotate: DAffine2 = DAffine2::from_angle(angle);
let translate_inverse = translate.inverse();
let mut rotated_subpath = self.clone();
rotated_subpath.apply_transform(translate * rotate * translate_inverse);
rotated_subpath
}
}