| |
|
|
| use crate::curve::{Curve, CurveManipulatorGroup, ValueMapperNode}; |
| use bezier_rs::{Bezier, TValue}; |
| use graphene_core::color::{Channel, Linear}; |
| use graphene_core::context::Ctx; |
|
|
| const WINDOW_SIZE: usize = 1024; |
|
|
| #[node_macro::node(category(""))] |
| fn generate_curves<C: Channel + Linear>(_: impl Ctx, curve: Curve, #[implementations(f32, f64)] _target_format: C) -> ValueMapperNode<C> { |
| let [mut pos, mut param]: [[f32; 2]; 2] = [[0.; 2], curve.first_handle]; |
| let mut lut = vec![C::from_f64(0.); WINDOW_SIZE]; |
| let end = CurveManipulatorGroup { |
| anchor: [1.; 2], |
| handles: [curve.last_handle, [0.; 2]], |
| }; |
| for sample in curve.manipulator_groups.iter().chain(std::iter::once(&end)) { |
| let [x0, y0, x1, y1, x2, y2, x3, y3] = [pos[0], pos[1], param[0], param[1], sample.handles[0][0], sample.handles[0][1], sample.anchor[0], sample.anchor[1]].map(f64::from); |
|
|
| let bezier = Bezier::from_cubic_coordinates(x0, y0, x1, y1, x2, y2, x3, y3); |
|
|
| let [left, right] = [pos[0], sample.anchor[0]].map(|c| c.clamp(0., 1.)); |
| let lut_index_left: usize = (left * (lut.len() - 1) as f32).floor() as _; |
| let lut_index_right: usize = (right * (lut.len() - 1) as f32).ceil() as _; |
| for index in lut_index_left..=lut_index_right { |
| let x = index as f64 / (lut.len() - 1) as f64; |
| let y = if x <= x0 { |
| y0 |
| } else if x >= x3 { |
| y3 |
| } else { |
| bezier.find_tvalues_for_x(x) |
| .next() |
| .map(|t| bezier.evaluate(TValue::Parametric(t.clamp(0., 1.))).y) |
| |
| .unwrap_or_else(|| (x - x0) / (x3 - x0) * (y3 - y0) + y0) |
| }; |
| lut[index] = C::from_f64(y); |
| } |
|
|
| pos = sample.anchor; |
| param = sample.handles[1]; |
| } |
| ValueMapperNode::new(lut) |
| } |
|
|
