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Each Extrude & Bevel and Inflate solid now takes up to 65,536 outline points (was 2,048) and 163,840 faces (was 32,768), VectorCraft's own limits, as Revolve's. Before any point is sampled, the outline's lines and curves are counted with each curve's tolerance pieces, and the faces the walls, bevels and caps (Extrude) or the sides (Inflate) need. When they do not fit, every curve takes fewer pieces, down to 4; a shape that does not fit at 4 is refused with the existing surface error before any face is built. The subpath count is capped at the point limit too. The error texts are unchanged. A closed path of 2,000 curves now extrudes with a bevel and inflates, and paths of 5,000 and 10,000 curves build at the default settings. Docs: docs/three-d.md, docs/mcp.md, docs/target-app-parity.md.
881 lines
39 KiB
Rust
881 lines
39 KiB
Rust
//! Portable 3D effect geometry: Revolve, Extrude & Bevel, Inflate and Rotate. No windowing, GPU or
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//! document dependencies.
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//!
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//! Open profiles optionally close their circular ends with caps. Faces are projected and sorted back to front,
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//! then flat or smoothly shaded with vector gradients. This preview uses a painter's algorithm, not a depth buffer:
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//! intersecting profiles can have ambiguous visibility and are not solid modelling inputs.
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#![forbid(unsafe_code)]
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mod solid;
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mod visibility;
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pub use solid::{Bevel, BevelShape, Extrude, Facet, Inflate, View, extrude, inflate, inflate_together, plane};
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pub use visibility::{VisibleFace, visible_faces};
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mod shading;
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pub use shading::{ClassicShading, ClassicSurface, LightGradient, RgbGradient, ShadeGradient};
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mod lights;
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pub use lights::{Light, Lights, MAX_LIGHTS};
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mod caps;
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mod mesh;
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pub use mesh::{Mesh, extrude_mesh, inflate_meshes, plane_mesh, revolve_mesh};
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use vectorcraft_geom::{BezPath, FillRule, ParamCurve, PathData, Point, Rect, Shape, Vec2, kurbo::ParamCurveDeriv};
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/// Resource limits shared by desktop, CLI and browser evaluation.
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const MAX_PROFILE_POINTS: usize = 16_384;
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const MAX_FACES: usize = 32768;
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/// Most faces Revolve builds for one object, its members together: about 460 MB of drawn art.
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const MAX_REVOLVE_FACES: usize = 163_840;
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/// Most faces Extrude & Bevel and Inflate build for one solid, as many as Revolve's.
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const MAX_SOLID_FACES: usize = MAX_REVOLVE_FACES;
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/// Samples a curved profile segment takes, and the fewest it takes on a surface over its budget.
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const CURVE_SAMPLES: usize = 16;
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const MIN_CURVE_SAMPLES: usize = 4;
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#[derive(Clone, Copy, Debug, Default, PartialEq)]
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struct V3(f64, f64, f64);
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impl V3 {
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fn sub(self, b: Self) -> Self {
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Self(self.0 - b.0, self.1 - b.1, self.2 - b.2)
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}
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fn cross(self, b: Self) -> Self {
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Self(self.1 * b.2 - self.2 * b.1, self.2 * b.0 - self.0 * b.2, self.0 * b.1 - self.1 * b.0)
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}
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fn dot(self, b: Self) -> f64 {
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self.0 * b.0 + self.1 * b.1 + self.2 * b.2
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}
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fn unit(self) -> Self {
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let l = self.dot(self).sqrt();
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if l < 1e-12 { Self::default() } else { Self(self.0 / l, self.1 / l, self.2 / l) }
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}
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}
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/// The vertical axis is offset outward from the selected edge of the profile's bounds.
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#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
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pub enum Edge {
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#[default]
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Left,
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Right,
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}
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/// All angles are degrees; offset is in document points, lighting values are 0..1 (ambient 0..2).
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#[derive(Clone, Copy, Debug, PartialEq)]
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pub struct Revolve {
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pub angle: f64,
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pub offset: f64,
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pub edge: Edge,
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pub rotation_x: f64,
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pub rotation_y: f64,
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pub rotation_z: f64,
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/// Perspective, 0° (none) to 160°: see [`eye_distance`].
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pub perspective: f64,
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/// Radial subdivisions for a full turn, clamped to 8..128.
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pub segments: usize,
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/// The light's Rotation, −180° to 180°: round the object on the page, 0° on its right and
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/// counterclockwise.
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pub light_rotation: f64,
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/// The light's Height, 0° to 90°: from beside the object (0°) to straight in front of it.
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pub light_height: f64,
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/// The light is behind the object (Move light to the back of object) rather than in front.
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pub light_behind: bool,
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/// Opaque RGB light color, each channel 0..1. Ambient light stays neutral.
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pub light_color: [f64; 3],
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pub light_intensity: f64,
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/// Softness, 0 (a sharp fall-off) to 1: how far round the object the light reaches.
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pub light_softness: f64,
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/// Explicit light list. None retains the earlier single-light parameters exactly.
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pub lights: Option<Lights>,
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/// Ambient Light, 0 to 2.
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pub ambient: f64,
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pub shade: bool,
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/// Interpolate profile normals using vector gradients. Enabled by default.
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pub smooth_shading: bool,
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/// Close circular endpoint rings of open profiles. Partial sweeps get sectors;
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/// the angular cut sides are left open. Enabled by default.
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pub cap_ends: bool,
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/// Samples for each curved profile segment, from [`revolve_curve_samples`] for the surfaces of
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/// one object. `None` plans them from the profile alone.
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pub curve_samples: Option<usize>,
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}
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/// The default light's Rotation and Height: the light of the earlier default direction (45° to the
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/// left of the eye and 45° up), to the left of and above the object, 30° in front of it.
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pub const DEFAULT_LIGHT: (f64, f64) = (125.264_389_682_754_65, 30.0);
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impl Default for Revolve {
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fn default() -> Self {
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Self {
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angle: 360.0,
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offset: 0.0,
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edge: Edge::Left,
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rotation_x: 0.0,
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rotation_y: 0.0,
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rotation_z: 0.0,
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perspective: 0.0,
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segments: 64,
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light_rotation: DEFAULT_LIGHT.0,
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light_height: DEFAULT_LIGHT.1,
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light_behind: false,
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light_color: [1.0; 3],
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light_intensity: 0.8,
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light_softness: 0.0,
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lights: None,
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ambient: 0.25,
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shade: true,
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smooth_shading: true,
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cap_ends: true,
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curve_samples: None,
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}
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}
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}
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/// The widest documented Perspective.
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pub const MAX_PERSPECTIVE: f64 = 160.0;
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/// How far the eye is from the centre of an object of half size `size`, for a Perspective of
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/// `angle` degrees: from where a sphere of √3 × `size` about the centre (the box around the object
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/// fits inside it) fills that angle of the view. 0° is no perspective (`None`, the eye infinitely
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/// far); at 160° the eye is just outside the sphere, so never inside the object.
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fn eye_distance(angle: f64, size: f64) -> Option<f64> {
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let angle = finite(angle, 0.0, 0.0, MAX_PERSPECTIVE);
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(angle > 0.0).then(|| 3f64.sqrt() * size / (angle / 2.0).to_radians().sin())
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}
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/// The scale of a view-space point `z` in front of the object's centre plane, for an eye at
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/// `eye`: 1 without perspective. Parts reaching past the eye's sphere (a wide outward bevel at a
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/// wide angle) are held just in front of the eye rather than turned inside out.
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fn perspective_scale(eye: Option<f64>, z: f64) -> f64 {
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eye.map_or(1.0, |e| e / (e - z).max(e * 1e-3))
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}
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/// The Perspective angle that shows exactly what the earlier 0–1 perspective strength did (files
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/// from before the angle). The strength put the eye at 4 × the object's half size / strength, so
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/// sin(angle / 2) = √3 × strength / 4: full strength is about 51°.
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pub fn perspective_from_strength(strength: f64) -> f64 {
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let s = finite(strength, 0.0, 0.0, 1.0);
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2.0 * (3f64.sqrt() * s / 4.0).asin().to_degrees()
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}
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/// The Rotation, Height and side of the light an earlier effect set by its azimuth (degrees round
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/// the vertical axis, 0° at the eye) and elevation (degrees up): the same direction, so it lights
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/// the object exactly as before.
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pub fn light_from_azimuth_elevation(azimuth: f64, elevation: f64) -> (f64, f64, bool) {
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let (azimuth, elevation) = (finite(azimuth, -45.0, -360.0, 360.0), finite(elevation, 45.0, -90.0, 90.0));
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let (sl, cl) = elevation.to_radians().sin_cos();
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let (sa, ca) = azimuth.to_radians().sin_cos();
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let [x, y, z] = [cl * sa, -sl, cl * ca];
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// Straight in front or behind, any Rotation is the same light.
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let rotation = if x.hypot(y) < 1e-12 { 0.0 } else { (-y).atan2(x).to_degrees() + 0.0 };
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(rotation, z.abs().min(1.0).asin().to_degrees(), z < 0.0)
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}
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/// How bright a face with unit normal `n` is under the light `l` (both in view space): the ambient
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/// light plus the light's intensity where it reaches. Without softness the light falls off with
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/// the cosine to nothing at 90°; softness wraps it further round the object, at 100 % to nothing
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/// only straight away from it. Never brighter than the art's own colour.
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fn brightness(o: &Revolve, n: V3, l: V3) -> f64 {
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if !o.shade {
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return 1.0;
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}
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if o.lights.is_some() {
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let rgb = illumination(o, n, l);
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return (rgb[0] + rgb[1] + rgb[2]) / 3.0;
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}
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let s = o.light_softness;
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let lit = ((n.dot(l) + s) / (1.0 + s)).max(0.0);
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(o.ambient + o.light_intensity * lit).clamp(0.0, 1.0)
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}
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fn direct_light(o: &Revolve, n: V3, l: V3) -> f64 {
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o.light_intensity * ((n.dot(l) + o.light_softness) / (1.0 + o.light_softness)).max(0.0)
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}
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fn illumination(o: &Revolve, n: V3, l: V3) -> [f64; 3] {
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if !o.shade {
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return [1.0; 3];
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}
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if o.lights.is_some() {
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return unclipped_illumination(o, n, l).map(|v| v.clamp(0.0, 1.0));
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}
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let direct = direct_light(o, n, l);
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o.light_color.map(|c| (o.ambient + direct * c).clamp(0.0, 1.0))
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}
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fn unclipped_illumination(o: &Revolve, n: V3, legacy_light: V3) -> [f64; 3] {
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let mut rgb = [o.ambient; 3];
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if let Some(lights) = o.lights {
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for light in lights.iter() {
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let direct = light.direct(n);
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for (out, color) in rgb.iter_mut().zip(light.color) {
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*out += direct * color;
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}
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}
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} else {
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let direct = direct_light(o, n, legacy_light);
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for (out, color) in rgb.iter_mut().zip(o.light_color) {
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*out += direct * color;
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}
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}
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rgb
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}
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fn finite(v: f64, fallback: f64, min: f64, max: f64) -> f64 {
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if v.is_finite() { v.clamp(min, max) } else { fallback }
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}
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impl Revolve {
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/// Unit bases of the rings that adjust the Euler X, Y and Z view parameters.
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/// X turns before Y and Z, Y before Z, and Z turns in the screen plane.
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/// Each pair has a cross product pointing along that parameter's rotation axis.
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pub fn rotation_planes(self) -> [[[f64; 3]; 2]; 3] {
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let o = self.sanitized();
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let x_frame = Self { rotation_x: 0.0, ..o };
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let y_frame = Self { rotation_x: 0.0, rotation_y: 0.0, ..o };
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[
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[x_frame.rotate(V3(0.0, 1.0, 0.0)), x_frame.rotate(V3(0.0, 0.0, 1.0))],
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[y_frame.rotate(V3(1.0, 0.0, 0.0)), y_frame.rotate(V3(0.0, 0.0, -1.0))],
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[V3(1.0, 0.0, 0.0), V3(0.0, 1.0, 0.0)],
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]
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.map(|plane| plane.map(|v| [v.0, v.1, v.2]))
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}
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/// The fixed centre of view rotation, in document coordinates.
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pub fn rotation_origin(self, bounds: Rect) -> Point {
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let o = self.sanitized();
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Point::new(if o.edge == Edge::Left { bounds.x0 - o.offset } else { bounds.x1 + o.offset }, bounds.center().y)
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}
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/// Rotated unit axes for a view-orientation guide (screen Y points down).
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pub fn view_axes(self) -> [Point; 3] {
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[V3(1.0, 0.0, 0.0), V3(0.0, 1.0, 0.0), V3(0.0, 0.0, 1.0)].map(|v| {
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let p = self.sanitized().rotate(v);
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Point::new(p.0, p.1)
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})
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}
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/// The same projected vertical axis used by the surface evaluator.
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pub fn projected_axis(self, bounds: Rect) -> [Point; 2] {
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let o = self.sanitized();
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let axis = match o.edge {
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Edge::Left => bounds.x0 - o.offset,
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Edge::Right => bounds.x1 + o.offset,
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};
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let center_y = bounds.center().y;
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let radius = (bounds.x0 - axis).abs().max((bounds.x1 - axis).abs());
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let eye = eye_distance(o.perspective, radius.max(bounds.height().abs()).max(1.0));
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[bounds.y0, bounds.y1].map(|y| {
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let v = o.rotate(V3(0.0, y - center_y, 0.0));
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let factor = perspective_scale(eye, v.2);
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Point::new(axis + v.0 * factor, center_y + v.1 * factor)
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})
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}
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/// Directional light in view space, shared by shading and interactive guides.
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pub fn light_direction(self) -> [f64; 3] {
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let o = self.sanitized();
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let (sr, cr) = o.light_rotation.to_radians().sin_cos();
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let (sh, ch) = o.light_height.to_radians().sin_cos();
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[ch * cr, -ch * sr, if o.light_behind { -sh } else { sh }]
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}
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/// Light-direction orbits as (centre, cosine basis, sine basis), in view space.
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/// The first changes the Rotation at the current Height: a circle on the page. The second
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/// changes the Height at the current Rotation; its parameter runs 0..90 degrees.
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pub fn light_orbits(self) -> [[[f64; 3]; 3]; 2] {
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let o = self.sanitized();
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let (sr, cr) = o.light_rotation.to_radians().sin_cos();
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let (sh, ch) = o.light_height.to_radians().sin_cos();
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let side = if o.light_behind { -1.0 } else { 1.0 };
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[[[0.0, 0.0, side * sh], [ch, 0.0, 0.0], [0.0, -ch, 0.0]], [[0.0, 0.0, 0.0], [cr, -sr, 0.0], [0.0, 0.0, side]]]
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}
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/// The Rotation and Height of a light dragged to `point` on the page (in units of the light
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/// guide's radius, y down), on the side it is already on: the further out, the lower. At the
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/// centre the Rotation is kept.
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pub fn light_at_on_side(self, point: Point) -> [f64; 2] {
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let o = self.sanitized();
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let point = Point::new(finite(point.x, 0.0, -1e8, 1e8), finite(point.y, 0.0, -1e8, 1e8));
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let r = point.x.hypot(point.y);
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let rotation = if r < 1e-9 { o.light_rotation } else { (-point.y).atan2(point.x).to_degrees() };
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[rotation, r.min(1.0).acos().to_degrees()]
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}
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fn sanitized(self) -> Self {
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Self {
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angle: finite(self.angle, 360.0, 0.0, 360.0),
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offset: finite(self.offset, 0.0, 0.0, 1e5),
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rotation_x: finite(self.rotation_x, 0.0, -360.0, 360.0),
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rotation_y: finite(self.rotation_y, 0.0, -360.0, 360.0),
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rotation_z: finite(self.rotation_z, 0.0, -360.0, 360.0),
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perspective: finite(self.perspective, 0.0, 0.0, MAX_PERSPECTIVE),
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segments: self.segments.clamp(8, 128),
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light_rotation: (finite(self.light_rotation, DEFAULT_LIGHT.0, -1e6, 1e6) + 180.0).rem_euclid(360.0) - 180.0,
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light_height: finite(self.light_height, DEFAULT_LIGHT.1, 0.0, 90.0),
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light_intensity: finite(self.light_intensity, 0.8, 0.0, 1.0),
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light_softness: finite(self.light_softness, 0.0, 0.0, 1.0),
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light_color: self.light_color.map(|c| finite(c, 1.0, 0.0, 1.0)),
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ambient: finite(self.ambient, 0.25, 0.0, 2.0),
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..self
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}
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}
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/// How many steps a sanitized sweep takes.
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fn steps(self) -> usize {
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((self.segments as f64 * self.angle / 360.0).ceil() as usize).max(1)
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}
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fn rotate(self, v: V3) -> V3 {
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let (sx, cx) = self.rotation_x.to_radians().sin_cos();
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let (sy, cy) = self.rotation_y.to_radians().sin_cos();
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let (sz, cz) = self.rotation_z.to_radians().sin_cos();
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let v = V3(v.0, cx * v.1 - sx * v.2, sx * v.1 + cx * v.2);
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let v = V3(cy * v.0 + sy * v.2, v.1, -sy * v.0 + cy * v.2);
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V3(cz * v.0 - sz * v.1, sz * v.0 + cz * v.1, v.2)
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}
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}
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/// One projected vector face. Brightness multiplies the source colour; an optional
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/// gradient replaces that constant brightness for a smoothly shaded triangle.
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#[derive(Clone, Debug, PartialEq)]
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pub struct Face {
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pub points: Vec<Point>,
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pub depth: f64,
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pub brightness: f64,
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pub gradient: Option<ShadeGradient>,
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/// RGB illumination and its unclipped smooth ramp, independent of the legacy white ramp.
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pub illumination: [f64; 3],
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pub light_gradient: Option<LightGradient>,
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pub rgb_gradient: Option<RgbGradient>,
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/// Curved vector boundary; points remain a bounded visibility approximation.
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pub outline: Option<PathData>,
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/// A single endpoint disk or sector, with its axis centre first in points.
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pub cap: bool,
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/// Bounded radial strips for a body face joining two curved endpoint rings.
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pub visibility_pieces: Option<Vec<Vec<Point>>>,
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}
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impl Face {
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pub fn path(&self) -> PathData {
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if let Some(path) = &self.outline {
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return path.clone();
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}
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let mut bp = BezPath::new();
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if let Some(first) = self.points.first() {
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bp.move_to(*first);
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for p in self.points.iter().skip(1) {
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bp.line_to(*p);
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}
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bp.close_path();
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}
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PathData::from_bezpath(&bp)
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}
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}
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/// Body faces and a cap's planar seed use identical two-sided shading and projection.
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fn project_face(vertices: &[V3], normals: Option<&[V3]>, o: Revolve, origin: Point, eye: Option<f64>, light: V3) -> Result<Option<Face>, String> {
|
||
let Some(first) = vertices.first() else { return Ok(None) };
|
||
// A triangle fan also handles a quad whose first edge lies on the axis.
|
||
let mut normal = vertices
|
||
.get(1..)
|
||
.unwrap_or_default()
|
||
.windows(2)
|
||
.filter_map(|pair| {
|
||
let [a, b] = pair else { return None };
|
||
Some(a.sub(*first).cross(b.sub(*first)).unit())
|
||
})
|
||
.find(|n| n.dot(*n) >= 0.5)
|
||
.unwrap_or_default();
|
||
if normal.dot(normal) < 0.5 {
|
||
return Ok(None);
|
||
}
|
||
// Profiles may run up or down. Shade the visible side of this two-sided surface.
|
||
if normal.2 < 0.0 {
|
||
normal = V3(-normal.0, -normal.1, -normal.2);
|
||
}
|
||
let flat_brightness = brightness(&o, normal, light);
|
||
let points: Vec<_> = vertices
|
||
.iter()
|
||
.map(|v| {
|
||
let factor = perspective_scale(eye, v.2);
|
||
Point::new(origin.x + v.0 * factor, origin.y + v.1 * factor)
|
||
})
|
||
.collect();
|
||
if points.iter().any(|p| !p.x.is_finite() || !p.y.is_finite()) {
|
||
return Err("Revolve projection is not finite".into());
|
||
}
|
||
let area = points
|
||
.iter()
|
||
.zip(points.iter().cycle().skip(1))
|
||
.take(points.len())
|
||
.map(|(a, b)| (a.x - origin.x) * (b.y - origin.y) - (b.x - origin.x) * (a.y - origin.y))
|
||
.sum::<f64>();
|
||
if area.abs() < 1e-10 {
|
||
return Ok(None);
|
||
}
|
||
let (brightness, gradient) = if let Some(normals) = normals {
|
||
let values: Vec<_> = normals
|
||
.iter()
|
||
.map(|n| {
|
||
let n = if n.dot(normal) < 0.0 { V3(-n.0, -n.1, -n.2) } else { *n };
|
||
brightness(&o, n, light)
|
||
})
|
||
.collect();
|
||
let brightness = if values.is_empty() { flat_brightness } else { values.iter().sum::<f64>() / values.len() as f64 };
|
||
(brightness, ShadeGradient::triangle(&points, &values))
|
||
} else {
|
||
(flat_brightness, None)
|
||
};
|
||
let (illumination, light_gradient) = if let Some(normals) = normals {
|
||
let normals: Vec<_> = normals.iter().map(|n| if n.dot(normal) < 0.0 { V3(-n.0, -n.1, -n.2) } else { *n }).collect();
|
||
let mut rgb = [0.0; 3];
|
||
for n in &normals {
|
||
for (out, value) in rgb.iter_mut().zip(illumination(&o, *n, light)) {
|
||
*out += value;
|
||
}
|
||
}
|
||
let rgb = if normals.is_empty() { illumination(&o, normal, light) } else { rgb.map(|v| v / normals.len() as f64) };
|
||
let ramp = if o.shade && o.lights.is_none() && o.light_color != [1.0; 3] {
|
||
let values: Vec<_> = normals.iter().map(|n| direct_light(&o, *n, light)).collect();
|
||
ShadeGradient::triangle(&points, &values).map(|diffuse| LightGradient { diffuse, ambient: o.ambient, color: o.light_color })
|
||
} else {
|
||
None
|
||
};
|
||
(rgb, ramp)
|
||
} else {
|
||
(illumination(&o, normal, light), None)
|
||
};
|
||
let rgb_gradient = normals.filter(|_| o.shade && o.lights.is_some()).and_then(|normals| {
|
||
let values: Vec<_> =
|
||
normals.iter().map(|n| unclipped_illumination(&o, if n.dot(normal) < 0.0 { V3(-n.0, -n.1, -n.2) } else { *n }, light)).collect();
|
||
RgbGradient::triangle(&points, &values)
|
||
});
|
||
Ok(Some(Face {
|
||
points,
|
||
depth: vertices.iter().map(|v| v.2).sum::<f64>() / vertices.len() as f64,
|
||
brightness,
|
||
gradient,
|
||
illumination,
|
||
light_gradient,
|
||
rgb_gradient,
|
||
outline: None,
|
||
cap: false,
|
||
visibility_pieces: None,
|
||
}))
|
||
}
|
||
|
||
/// Evaluate a profile in document space. All subpaths share one axis from `bounds`.
|
||
/// Invalid or excessively complex inputs return an error, never a partial surface.
|
||
pub fn revolve(path: &PathData, bounds: Rect, options: Revolve) -> Result<Vec<Face>, String> {
|
||
revolve_faces(path, FillRule::NonZero, bounds, options, None)
|
||
}
|
||
|
||
const TOO_COMPLEX_PROFILE: &str = "Revolve profile is too complex";
|
||
const TOO_COMPLEX_SURFACE: &str = "Revolve surface is too complex; reduce Segments or simplify the profile";
|
||
|
||
/// The samples each curved segment takes when `paths`, the profiles of one object's surfaces, are
|
||
/// revolved with `options`: [`CURVE_SAMPLES`] when every surface fits the limits together, else as
|
||
/// many as fit, the same number for every curve. An error when [`MIN_CURVE_SAMPLES`] do not fit.
|
||
/// The count is made before any face is built.
|
||
pub fn revolve_curve_samples<'a>(paths: impl IntoIterator<Item = &'a PathData>, options: Revolve) -> Result<usize, String> {
|
||
let o = options.sanitized();
|
||
let steps = o.steps();
|
||
let per_edge = if o.shade && o.smooth_shading { steps.saturating_mul(2) } else { steps };
|
||
let (mut anchors, mut contours, mut lines, mut curves, mut caps) = (0usize, 0usize, 0usize, 0usize, 0usize);
|
||
for sp in paths.into_iter().flat_map(|p| &p.subpaths) {
|
||
anchors = anchors.saturating_add(sp.anchors.len());
|
||
contours += 1;
|
||
if anchors > MAX_PROFILE_POINTS || contours > MAX_PROFILE_POINTS {
|
||
return Err(TOO_COMPLEX_PROFILE.into());
|
||
}
|
||
let segments = if sp.closed { sp.anchors.len() } else { sp.anchors.len().saturating_sub(1) };
|
||
for i in 0..segments {
|
||
if sp.segment_is_line(i) {
|
||
lines += 1;
|
||
} else {
|
||
curves += 1;
|
||
}
|
||
}
|
||
if o.cap_ends && !sp.closed && segments > 0 {
|
||
caps += 2;
|
||
}
|
||
}
|
||
let points = MAX_PROFILE_POINTS.saturating_sub(contours);
|
||
if lines.saturating_add(curves.saturating_mul(MIN_CURVE_SAMPLES)) > points {
|
||
return Err(TOO_COMPLEX_PROFILE.into());
|
||
}
|
||
let edges = (MAX_REVOLVE_FACES.saturating_sub(caps.saturating_mul(steps)) / per_edge).min(points);
|
||
if curves == 0 {
|
||
return if lines > edges { Err(TOO_COMPLEX_SURFACE.into()) } else { Ok(CURVE_SAMPLES) };
|
||
}
|
||
let samples = (edges.saturating_sub(lines) / curves).min(CURVE_SAMPLES);
|
||
if samples < MIN_CURVE_SAMPLES { Err(TOO_COMPLEX_SURFACE.into()) } else { Ok(samples) }
|
||
}
|
||
|
||
/// Most work the search for holes does: each winding test counts its contour's elements, and each
|
||
/// contour placed in a cell of the grid or looked at as a candidate for a point counts one.
|
||
const MAX_HOLE_WORK: usize = 16_000_000;
|
||
|
||
/// Most cells along each side of the grid the search for holes sorts contours into.
|
||
const MAX_HOLE_GRID: usize = 256;
|
||
|
||
/// For each segment of each subpath of `path`, whether it walls a hole under `rule`: the fill is
|
||
/// outside its closed contour at the segment's middle and not inside. An error past
|
||
/// [`MAX_HOLE_WORK`].
|
||
#[cfg(test)]
|
||
fn hole_segments(path: &PathData, rule: FillRule) -> Result<Vec<Vec<bool>>, String> {
|
||
hole_segments_counted(path, rule).map(|(holes, _)| holes)
|
||
}
|
||
|
||
/// [`hole_segments`] and the work it did.
|
||
#[cfg(test)]
|
||
fn hole_segments_counted(path: &PathData, rule: FillRule) -> Result<(Vec<Vec<bool>>, usize), String> {
|
||
let mut search = HoleSearch::new(path, rule)?;
|
||
let mut holes = Vec::with_capacity(path.subpaths.len());
|
||
for (i, sp) in path.subpaths.iter().enumerate() {
|
||
let segments = if sp.closed { sp.anchors.len() } else { 0 };
|
||
holes.push((0..segments).map(|segment| search.is_hole(i, sp.segment(segment).eval(0.5))).collect::<Result<Vec<_>, _>>()?);
|
||
}
|
||
Ok((holes, search.work))
|
||
}
|
||
|
||
/// The closed contours of a profile sorted into a grid over the bounds of them all, each listed in
|
||
/// the cells its bounds reach into, to find which parts of the profile's edges wall a hole under
|
||
/// its fill rule. A point is tested only against the contours of its cell. Every test counts
|
||
/// toward [`MAX_HOLE_WORK`].
|
||
struct HoleSearch {
|
||
/// Each subpath's outline, its bounds, and for a closed one which way it winds.
|
||
contours: Vec<(BezPath, Rect, Option<i32>)>,
|
||
rule: FillRule,
|
||
area: Option<Rect>,
|
||
side: usize,
|
||
grid: Vec<Vec<usize>>,
|
||
work: usize,
|
||
}
|
||
|
||
impl HoleSearch {
|
||
fn new(path: &PathData, rule: FillRule) -> Result<Self, String> {
|
||
// Each contour takes a profile point, as in `revolve_curve_samples`.
|
||
if path.subpaths.len() > MAX_PROFILE_POINTS {
|
||
return Err(TOO_COMPLEX_PROFILE.into());
|
||
}
|
||
let contours: Vec<(BezPath, Rect, Option<i32>)> = path
|
||
.subpaths
|
||
.iter()
|
||
.map(|sp| {
|
||
let contour = PathData::new(vec![sp.clone()]).to_bezpath();
|
||
let bounds = contour.bounding_box();
|
||
let direction = sp.closed.then(|| if contour.area() < 0.0 { -1 } else { 1 });
|
||
(contour, bounds, direction)
|
||
})
|
||
.collect();
|
||
let closed = || contours.iter().enumerate().filter(|(_, (_, _, d))| d.is_some());
|
||
let area = closed().map(|(_, (_, b, _))| *b).reduce(|a, b| a.union(b));
|
||
let side = ((closed().count() as f64).sqrt().ceil() as usize).clamp(1, MAX_HOLE_GRID);
|
||
let mut search = HoleSearch { contours: vec![], rule, area, side, grid: vec![vec![]; side * side], work: 0 };
|
||
for (j, (_, b, _)) in closed() {
|
||
let cells = search.cells(*b);
|
||
search.spend(cells.len())?;
|
||
for c in cells {
|
||
if let Some(c) = search.grid.get_mut(c) {
|
||
c.push(j);
|
||
}
|
||
}
|
||
}
|
||
search.contours = contours;
|
||
Ok(search)
|
||
}
|
||
|
||
fn spend(&mut self, n: usize) -> Result<(), String> {
|
||
self.work = self.work.saturating_add(n);
|
||
if self.work > MAX_HOLE_WORK { Err(TOO_COMPLEX_PROFILE.to_string()) } else { Ok(()) }
|
||
}
|
||
|
||
/// The grid cells `r` reaches into.
|
||
fn cells(&self, r: Rect) -> Vec<usize> {
|
||
let Some(a) = self.area else { return vec![] };
|
||
let side = self.side;
|
||
let at = |v: f64, lo: f64, hi: f64| {
|
||
let span = hi - lo;
|
||
if span > 0.0 { (((v - lo) / span * side as f64).floor().max(0.0) as usize).min(side - 1) } else { 0 }
|
||
};
|
||
let (x0, x1) = (at(r.x0, a.x0, a.x1), at(r.x1, a.x0, a.x1));
|
||
let (y0, y1) = (at(r.y0, a.y0, a.y1), at(r.y1, a.y0, a.y1));
|
||
(y0..=y1).flat_map(|y| (x0..=x1).map(move |x| y * side + x)).collect()
|
||
}
|
||
|
||
/// The closed contours other than `own` whose bounds may meet `r`, each once.
|
||
fn candidates(&mut self, own: usize, r: Rect) -> Result<Vec<usize>, String> {
|
||
let mut out = vec![];
|
||
for c in self.cells(r) {
|
||
let listed = self.grid.get(c).map_or(&[][..], Vec::as_slice);
|
||
out.extend(listed.iter().copied().filter(|j| *j != own));
|
||
}
|
||
self.spend(out.len())?;
|
||
out.sort_unstable();
|
||
out.dedup();
|
||
Ok(out)
|
||
}
|
||
|
||
/// Whether the edge of closed subpath `own` at `p` walls a hole: the fill is outside its
|
||
/// contour there and not inside.
|
||
fn is_hole(&mut self, own: usize, p: Point) -> Result<bool, String> {
|
||
let Some(direction) = self.contours.get(own).and_then(|c| c.2) else { return Ok(false) };
|
||
let mut others = 0i32;
|
||
for j in self.candidates(own, Rect::from_points(p, p))? {
|
||
let Some((contour, bounds, Some(_))) = self.contours.get(j) else { continue };
|
||
if !bounds.contains(p) {
|
||
continue;
|
||
}
|
||
let (elements, winding) = (contour.elements().len(), contour.winding(p));
|
||
self.spend(elements)?;
|
||
others += winding;
|
||
}
|
||
Ok(match self.rule {
|
||
FillRule::EvenOdd => others % 2 != 0,
|
||
FillRule::NonZero => others != 0 && others + direction == 0,
|
||
})
|
||
}
|
||
|
||
/// The line from `a` to `b` on subpath `own`, cut where it crosses another closed contour: each
|
||
/// part's end, the last one `b`, and whether that part walls a hole at its middle.
|
||
fn parts(&mut self, own: usize, a: Point, b: Point) -> Result<Vec<(Point, bool)>, String> {
|
||
let mut out = vec![];
|
||
let mut from = 0.0;
|
||
for t in self.crossings(own, a, b)?.into_iter().chain([1.0]) {
|
||
let hole = self.is_hole(own, a.lerp(b, (from + t) * 0.5))?;
|
||
out.push((if t < 1.0 { a.lerp(b, t) } else { b }, hole));
|
||
from = t;
|
||
}
|
||
Ok(out)
|
||
}
|
||
|
||
/// Where the line from `a` to `b` on closed subpath `own` crosses another closed contour, as
|
||
/// sorted fractions of the way from `a` to `b`, strictly between them.
|
||
fn crossings(&mut self, own: usize, a: Point, b: Point) -> Result<Vec<f64>, String> {
|
||
if self.contours.get(own).and_then(|c| c.2).is_none() {
|
||
return Ok(vec![]);
|
||
}
|
||
let line = vectorcraft_geom::kurbo::Line::new(a, b);
|
||
let reach = Rect::from_points(a, b);
|
||
let mut out = vec![];
|
||
for j in self.candidates(own, reach)? {
|
||
let Some((contour, bounds, Some(_))) = self.contours.get(j) else { continue };
|
||
if bounds.x0 > reach.x1 || bounds.x1 < reach.x0 || bounds.y0 > reach.y1 || bounds.y1 < reach.y0 {
|
||
continue;
|
||
}
|
||
let found: Vec<f64> = contour.segments().flat_map(|s| s.intersect_line(line)).map(|i| i.line_t).collect();
|
||
self.spend(contour.elements().len())?;
|
||
out.extend(found.into_iter().filter(|t| *t > 1e-9 && *t < 1.0 - 1e-9));
|
||
}
|
||
out.sort_by(f64::total_cmp);
|
||
out.dedup_by(|x, y| (*x - *y).abs() < 1e-9);
|
||
Ok(out)
|
||
}
|
||
}
|
||
|
||
/// [`revolve`], or with `mesh` the surface's faces before projection, kept there instead of drawn,
|
||
/// each turned out of the region `rule` fills.
|
||
fn revolve_faces(
|
||
path: &PathData,
|
||
rule: FillRule,
|
||
bounds: Rect,
|
||
options: Revolve,
|
||
mut mesh: Option<&mut Vec<solid::Face3>>,
|
||
) -> Result<Vec<Face>, String> {
|
||
let o = options.sanitized();
|
||
let curve_samples = match o.curve_samples {
|
||
Some(samples) => samples.clamp(1, CURVE_SAMPLES),
|
||
None => revolve_curve_samples([path], o)?,
|
||
};
|
||
// For a mesh, each piece of a closed contour's edge is cut where it crosses another contour, so
|
||
// each part's normal turns toward a hole only where it walls one.
|
||
let mut search = if mesh.is_some() { Some(HoleSearch::new(path, rule)?) } else { None };
|
||
// A face kept for a mesh: its normal follows from its corners.
|
||
let keep = |mesh: &mut Vec<solid::Face3>, face: Vec<V3>, normal: V3| {
|
||
mesh.push((vec![face], normal));
|
||
if mesh.len() > MAX_REVOLVE_FACES { Err(TOO_COMPLEX_SURFACE.to_string()) } else { Ok(()) }
|
||
};
|
||
if ![bounds.x0, bounds.y0, bounds.x1, bounds.y1].iter().all(|v| v.is_finite() && v.abs() <= 1e8) {
|
||
return Err("Revolve requires finite profile coordinates within 100 million points".into());
|
||
}
|
||
let axis = match o.edge {
|
||
Edge::Left => bounds.x0 - o.offset,
|
||
Edge::Right => bounds.x1 + o.offset,
|
||
};
|
||
let center_y = (bounds.y0 + bounds.y1) * 0.5;
|
||
let radius = (bounds.x0 - axis).abs().max((bounds.x1 - axis).abs());
|
||
let eye = eye_distance(o.perspective, radius.max(bounds.height().abs()).max(1.0));
|
||
let steps = o.steps();
|
||
let sweep = o.angle.to_radians();
|
||
let smooth = o.shade && o.smooth_shading;
|
||
let [lx, ly, lz] = o.light_direction();
|
||
let light = V3(lx, ly, lz);
|
||
let mut faces = Vec::new();
|
||
let vertex = |p: Point, step: usize| {
|
||
let (s, c) = (sweep * step as f64 / steps as f64).sin_cos();
|
||
o.rotate(V3((p.x - axis) * c, p.y - center_y, (p.x - axis) * s))
|
||
};
|
||
let normal = |tangent: Vec2, step: usize| {
|
||
let (s, c) = (sweep * step as f64 / steps as f64).sin_cos();
|
||
o.rotate(V3(tangent.y * c, -tangent.x, tangent.y * s).unit())
|
||
};
|
||
let mut mesh_cost = 0;
|
||
let mut emit = |face: Option<Face>, cost: usize| -> Result<(), String> {
|
||
if let Some(face) = face {
|
||
faces.push(face);
|
||
mesh_cost += cost;
|
||
if mesh_cost > MAX_REVOLVE_FACES {
|
||
return Err(TOO_COMPLEX_SURFACE.into());
|
||
}
|
||
}
|
||
Ok(())
|
||
};
|
||
let mut count = 0;
|
||
let mut curve_budget = 0;
|
||
for (contour, sp) in path.subpaths.iter().enumerate() {
|
||
let mut profile = Vec::new();
|
||
let mut tangents = Vec::new();
|
||
let mut hole_edges = Vec::new();
|
||
if let Some(first) = sp.anchors.first() {
|
||
profile.push(first.p);
|
||
count += 1;
|
||
if count > MAX_PROFILE_POINTS {
|
||
return Err(TOO_COMPLEX_PROFILE.into());
|
||
}
|
||
}
|
||
let segments = if sp.closed { sp.anchors.len() } else { sp.anchors.len().saturating_sub(1) };
|
||
// Bound work before sampling any data. Straight edges get one sample.
|
||
if segments > MAX_PROFILE_POINTS {
|
||
return Err(TOO_COMPLEX_PROFILE.into());
|
||
}
|
||
for i in 0..segments {
|
||
let curve = sp.segment(i);
|
||
let samples = if sp.segment_is_line(i) { 1 } else { curve_samples };
|
||
for k in 1..=samples {
|
||
let t0 = (k - 1) as f64 / samples as f64;
|
||
let t1 = k as f64 / samples as f64;
|
||
let b = curve.eval(t1);
|
||
let tangent = |t: f64| {
|
||
if !smooth {
|
||
return Vec2::ZERO;
|
||
}
|
||
let a = curve.eval(t0);
|
||
if samples == 1 {
|
||
return b - a;
|
||
}
|
||
let d = curve.deriv();
|
||
let v = d.eval(t).to_vec2();
|
||
if v.hypot2() > 1e-20 {
|
||
return v;
|
||
}
|
||
// Repeated endpoint handles still have a one-sided curve tangent.
|
||
let v = d.eval(t.clamp(1e-7, 1.0 - 1e-7)).to_vec2();
|
||
if v.hypot2() > 1e-20 { v } else { b - a }
|
||
};
|
||
let a = profile.last().copied().unwrap_or(b);
|
||
let parts = match search.as_mut() {
|
||
Some(search) => search.parts(contour, a, b)?,
|
||
None => vec![(b, false)],
|
||
};
|
||
for (end, hole) in parts {
|
||
tangents.push([tangent(t0), tangent(t1)]);
|
||
hole_edges.push(hole);
|
||
profile.push(end);
|
||
count += 1;
|
||
if count > MAX_PROFILE_POINTS {
|
||
return Err(TOO_COMPLEX_PROFILE.into());
|
||
}
|
||
}
|
||
}
|
||
}
|
||
let ends = o.cap_ends && !sp.closed && profile.len() >= 2 && profile.first().zip(profile.last()).is_some_and(|(a, b)| a.distance(*b) > 1e-10);
|
||
let mut rings = [None, None];
|
||
if ends {
|
||
for (ring, end) in rings.iter_mut().zip([profile.first(), profile.last()]) {
|
||
if let Some(end) = end
|
||
&& (end.x - axis).abs() > 1e-10
|
||
{
|
||
*ring = Some(caps::Ring::new(*end, bounds, o, steps, &mut curve_budget)?);
|
||
}
|
||
}
|
||
}
|
||
// For a mesh: which way the profile runs round the region it sweeps (closed against the
|
||
// axis at its ends when it is open), so the faces' normals point out of the solid.
|
||
let turn = {
|
||
let mut ring: Vec<(f64, f64)> = profile.iter().map(|p| (p.x - axis, p.y)).collect();
|
||
if let (false, Some(first), Some(last)) = (sp.closed, profile.first(), profile.last()) {
|
||
ring.extend([(0.0, last.y), (0.0, first.y)]);
|
||
}
|
||
let area: f64 = ring.iter().zip(ring.iter().cycle().skip(1)).take(ring.len()).map(|(p, q)| p.0 * q.1 - q.0 * p.1).sum();
|
||
if area < 0.0 { -1.0 } else { 1.0 }
|
||
};
|
||
for (i, ((pair, [ta, tb]), hole)) in profile.windows(2).zip(tangents).zip(hole_edges).enumerate() {
|
||
let [a, b] = pair else { continue };
|
||
let turn = if hole { -turn } else { turn };
|
||
if ![a.x, a.y, b.x, b.y].iter().all(|v| v.is_finite() && v.abs() <= 1e8) {
|
||
return Err("Revolve profile contains invalid coordinates".into());
|
||
}
|
||
for j in 0..steps {
|
||
let [v0, v1, v2, v3] = [vertex(*a, j), vertex(*b, j), vertex(*b, j + 1), vertex(*a, j + 1)];
|
||
if let Some(mesh) = mesh.as_deref_mut() {
|
||
// The edge's outward normal in the profile's plane (distance from the axis,
|
||
// height), swept to the middle of the step.
|
||
let (dr, dy) = ((b.x - a.x) * turn, (b.y - a.y) * turn);
|
||
let (s, c) = (sweep * (j as f64 + 0.5) / steps as f64).sin_cos();
|
||
keep(mesh, vec![v0, v1, v2, v3], o.rotate(V3(dy * c, -dr, dy * s)))?;
|
||
continue;
|
||
}
|
||
let first = (i == 0).then(|| rings.first().and_then(Option::as_ref).and_then(|r| r.arcs.get(j))).flatten();
|
||
let last = (i + 2 == profile.len()).then(|| rings.last().and_then(Option::as_ref).and_then(|r| r.arcs.get(j))).flatten();
|
||
let projected = |vertices: &[V3], normals: Option<&[V3]>, edges: &[(usize, &caps::RingArc, bool)]| {
|
||
let mut face = project_face(vertices, normals, o, Point::new(axis, center_y), eye, light)?;
|
||
if let Some(face) = &mut face {
|
||
caps::curve_edges(face, edges);
|
||
}
|
||
Ok::<_, String>(face)
|
||
};
|
||
if smooth {
|
||
let [n0, n1, n2, n3] = [normal(ta, j), normal(tb, j), normal(tb, j + 1), normal(ta, j + 1)];
|
||
emit(projected(&[v0, v1, v2], Some(&[n0, n1, n2]), &last.map(|arc| (1, arc, false)).into_iter().collect::<Vec<_>>())?, 1)?;
|
||
emit(projected(&[v0, v2, v3], Some(&[n0, n2, n3]), &first.map(|arc| (2, arc, true)).into_iter().collect::<Vec<_>>())?, 1)?;
|
||
} else {
|
||
let edges: Vec<_> = last.map(|arc| (1, arc, false)).into_iter().chain(first.map(|arc| (3, arc, true))).collect();
|
||
emit(projected(&[v0, v1, v2, v3], None, &edges)?, 1)?;
|
||
}
|
||
}
|
||
}
|
||
for (index, ring) in rings.iter().enumerate().filter_map(|(i, r)| r.as_ref().map(|r| (i, r))) {
|
||
let neighbours =
|
||
if index == 0 { profile.first().zip(profile.get(1)) } else { profile.last().zip(profile.get(profile.len().saturating_sub(2))) };
|
||
if let Some((end, neighbour)) = neighbours {
|
||
let dy = end.y - neighbour.y;
|
||
let outward = if dy.abs() > 1e-10 {
|
||
dy.signum()
|
||
} else if end.y < center_y {
|
||
-1.0
|
||
} else {
|
||
1.0
|
||
};
|
||
if let Some(mesh) = mesh.as_deref_mut() {
|
||
// The disk, or for a partial sweep the sector with its centre on the axis.
|
||
let mut cap: Vec<V3> = (0..=steps).map(|j| vertex(*end, j)).collect();
|
||
if o.angle >= 360.0 {
|
||
cap.pop();
|
||
} else {
|
||
cap.insert(0, o.rotate(V3(0.0, end.y - center_y, 0.0)));
|
||
}
|
||
keep(mesh, cap, o.rotate(V3(0.0, outward, 0.0)))?;
|
||
continue;
|
||
}
|
||
// Keep the original tessellation work budget, even though each cap
|
||
// now produces only one curved vector face.
|
||
emit(ring.face(bounds, o, light, outward)?, steps)?;
|
||
}
|
||
}
|
||
}
|
||
faces.sort_by(|a, b| a.depth.total_cmp(&b.depth));
|
||
Ok(faces)
|
||
}
|
||
|
||
#[cfg(test)]
|
||
mod tests;
|