use super::{begin_point_hit, polygon, shade, ChartColors, ChartData, Node, Point, Scene};
use crate::chart::{chart_node, child};
use std::f64::consts::{PI, TAU};
use std::fmt::Write;
struct Camera {
x: f64,
y: f64,
radius: f64,
thickness: f64,
sin: f64,
cos: f64,
focal: f64,
}
impl Camera {
fn project(&self, x: f64, z: f64, elevation: f64) -> Point {
let depth = z * self.cos - elevation * self.sin;
let scale = 1. / (1. + depth / self.focal);
Point {
x: self.x + x * scale,
y: self.y - (z * self.sin + elevation * self.cos) * scale,
}
}
fn rim(&self, angle: f64, offset: (f64, f64), elevation: f64) -> Point {
self.project(
self.radius * angle.sin() + offset.0,
self.radius * angle.cos() + offset.1,
elevation,
)
}
}
fn property(node: Node, name: &str) -> Option<f64> {
child(node, name)?
.attribute("val")?
.parse::<f64>()
.ok()
.filter(|v| v.is_finite())
}
struct Slice {
index: u32,
start: f64,
end: f64,
offset: (f64, f64),
fill: String,
stroke: String,
}
fn arc_angles(start: f64, end: f64) -> impl DoubleEndedIterator<Item = f64> {
let steps = ((end - start).abs().to_degrees() / 3.).ceil().max(1.) as usize;
(0..=steps).map(move |i| start + (end - start) * i as f64 / steps as f64)
}
fn side(out: &mut String, cam: &Camera, slice: &Slice, start: f64, end: f64, key: usize) {
let points: Vec<_> = arc_angles(start, end)
.map(|a| cam.rim(a, slice.offset, cam.thickness))
.chain(
arc_angles(start, end)
.rev()
.map(|a| cam.rim(a, slice.offset, 0.)),
)
.collect();
if slice.fill == "none" {
polygon(out, &points, "none", &slice.stroke);
return;
}
let right = points[0].x;
let left = cam.rim(end, slice.offset, cam.thickness).x;
let _ = write!(
out,
r#"<defs><linearGradient id="pie-side-{key}" gradientUnits="userSpaceOnUse" x1="{left:.3}" x2="{right:.3}" y1="0" y2="0">"#
);
let span = (right - left).max(f64::EPSILON);
let steps = ((end - start).to_degrees() / 5.).ceil().max(1.) as usize;
for i in 0..=steps {
let angle = end - (end - start) * i as f64 / steps as f64;
let position =
((cam.rim(angle, slice.offset, cam.thickness).x - left) / span).clamp(0., 1.);
let illumination = (0.395 - 0.432 * angle.sin() - 0.303 * angle.cos()).max(0.395);
let paint = shade(&slice.fill, illumination);
let _ = write!(
out,
r#"<stop offset="{position:.4}" stop-color="{paint}"/>"#
);
}
out.push_str("</linearGradient></defs>");
polygon(
out,
&points,
&format!("url(#pie-side-{key})"),
&slice.stroke,
);
}
pub(super) fn draw(
scene: &Scene,
data: &ChartData,
group: Node,
colors: &ChartColors,
out: &mut String,
) {
let Some((series_index, series)) = data
.series
.iter()
.enumerate()
.find(|(_, s)| s.chart_type == "pie3D")
else {
return;
};
let Some(source) = child(group, "ser") else {
return;
};
let view = group
.ancestors()
.find(|n| chart_node(*n, "chart"))
.and_then(|n| child(n, "view3D"));
let elevation = view
.and_then(|v| property(v, "rotX"))
.unwrap_or(14.82)
.clamp(0., 90.)
.to_radians();
let rotation = view
.and_then(|v| property(v, "rotY"))
.unwrap_or(0.)
.to_radians();
let perspective = view
.and_then(|v| property(v, "perspective"))
.unwrap_or(30.)
.clamp(0., 240.);
let perspective = if view
.and_then(|v| child(v, "rAngAx"))
.is_some_and(|n| !matches!(n.attribute("val"), Some("0" | "false" | "off")))
{
0.
} else {
perspective
};
let inset = 14.4_f64.min(0.1 * scene.width.min(scene.height));
let mut left = scene.left;
let mut top = scene.top;
let mut width = scene.width;
let mut height = scene.height;
if colors.spreadsheet_defaults {
use crate::parse::chart_svg::{font_size, on, text_props, text_width, val};
let chart = group.ancestors().find(|n| chart_node(*n, "chart"));
let automatic = chart
.and_then(|n| child(n, "plotArea"))
.and_then(|n| child(n, "layout"))
.and_then(|n| child(n, "manualLayout"))
.is_none();
if automatic {
let title = chart.and_then(|n| child(n, "title"));
if title.is_some() && !on(val(title, "overlay")) {
let size = font_size(text_props(title, true).or(text_props(title, false)), 24.);
let space = size * 1.17 + 12.;
top += space;
height -= space;
}
if let Some(legend) = chart
.and_then(|n| child(n, "legend"))
.filter(|n| !on(val(Some(*n), "overlay")))
{
let size = font_size(text_props(Some(legend), false), 40. / 3.);
let pos = val(Some(legend), "legendPos").unwrap_or("r");
if matches!(pos, "l" | "r" | "tr") {
let longest = series
.points
.iter()
.filter_map(|p| p.categories.first())
.map(|c| text_width(&c.label, size))
.fold(0., f64::max);
let space = longest + size * 1.055 + 13.333;
if pos == "l" {
left += space;
}
width -= space;
} else {
let space = size * 1.76 + 10.;
if pos == "t" {
top += space;
}
height -= space;
}
}
}
}
let inner_height = (height - 2. * inset).max(1.);
let inner_width = (width - 2. * inset).max(1.);
let focal = if perspective == 0. {
f64::INFINITY
} else {
inner_height * 1.067 / (perspective.to_radians() * 0.5).min(1.30).tan()
};
let depth = 0.243
* view
.and_then(|v| property(v, "depthPercent"))
.unwrap_or(100.)
.clamp(20., 2000.)
/ 100.;
let explosion = property(source, "explosion").unwrap_or(0.).clamp(0., 400.) / 100.;
let offsets: std::collections::HashMap<u32, f64> = source
.children()
.filter(|n| chart_node(*n, "dPt"))
.filter_map(|p| {
let idx = child(p, "idx")?.attribute("val")?.parse().ok()?;
Some((idx, property(p, "explosion")?.clamp(0., 400.) / 100.))
})
.collect();
let max_offset = offsets.values().copied().fold(explosion, f64::max);
let (sin, cos) = elevation.sin_cos();
let half_width = inner_width * 0.485;
let half_height = inner_height * 0.485;
let horizontal =
half_width / ((half_width * cos / focal).hypot(1.) + half_width * depth * sin / focal);
let front = half_height / (sin + half_height * cos / focal);
let back = half_height
/ (sin + depth * cos - half_height * (cos - depth * sin) / focal).max(f64::EPSILON);
let radius = horizontal.min(front).min(back) / (1. + max_offset);
let cam = Camera {
x: left + width / 2.,
y: top + height / 2. - 0.002 * radius,
radius,
thickness: radius * depth,
sin,
cos,
focal: focal.max(radius * (1. + depth + max_offset) * 1.1),
};
let values: Vec<_> = series
.points
.iter()
.filter_map(|p| {
let value = p.value.as_ref()?.parse::<f64>().ok()?.abs();
(value.is_finite() && value > 0.).then_some((p.index, value))
})
.collect();
let max_value = values.iter().map(|(_, v)| *v).fold(0., f64::max);
if max_value == 0. {
return;
}
let total: f64 = values.iter().map(|(_, v)| v / max_value).sum();
let mut angle = rotation.rem_euclid(TAU);
let mut slices = Vec::with_capacity(values.len());
for (idx, value) in values {
let end = angle + TAU * (value / max_value) / total;
let mid = (angle + end) / 2.;
let offset = offsets.get(&idx).copied().unwrap_or(explosion) * radius;
slices.push(Slice {
index: idx,
start: angle,
end,
offset: (offset * mid.sin(), offset * mid.cos()),
fill: colors.fill(series_index, Some(idx)),
stroke: colors
.outline(series_index, Some(idx))
.unwrap_or("none")
.to_owned(),
});
angle = end;
}
slices.sort_by(|a, b| b.offset.1.total_cmp(&a.offset.1));
for (i, slice) in slices.iter().enumerate() {
if colors.interactive {
let middle = (slice.start + slice.end) / 2.;
let anchor = cam.project(
slice.offset.0 + radius * 0.5 * middle.sin(),
slice.offset.1 + radius * 0.5 * middle.cos(),
cam.thickness,
);
begin_point_hit(out, colors, "slice", series_index, slice.index, anchor);
}
let center = |e| cam.project(slice.offset.0, slice.offset.1, e);
if slice.offset != (0., 0.) {
for (a, visible) in [
(slice.start, slice.start.sin() < 0.),
(slice.end, slice.end.sin() > 0.),
] {
if visible {
polygon(
out,
&[
center(0.),
cam.rim(a, slice.offset, 0.),
cam.rim(a, slice.offset, cam.thickness),
center(cam.thickness),
],
&shade(
&slice.fill,
if colors.spreadsheet_defaults {
0.4
} else {
0.65
},
),
&slice.stroke,
);
}
}
}
let tangent = (-(radius * cam.cos)
/ (cam.focal + slice.offset.1 * cam.cos - cam.thickness * cam.sin))
.clamp(-1., 1.)
.acos();
for period in 0..=1 {
let start = slice.start.max(tangent + TAU * period as f64);
let end = slice.end.min(TAU - tangent + TAU * period as f64);
if end > start {
side(out, &cam, slice, start, end, 2 * i + period);
}
}
let mut top: Vec<_> = arc_angles(slice.start, slice.end)
.map(|a| cam.rim(a, slice.offset, cam.thickness))
.collect();
if slice.end - slice.start < 2. * PI - 1e-10 {
top.push(center(cam.thickness));
}
let top_light = if colors.spreadsheet_defaults {
0.4 + 0.6 * (elevation - PI / 4.).cos()
} else {
0.923
};
let fill = shade(&slice.fill, top_light);
polygon(out, &top, &fill, &slice.stroke);
colors.end_hit(out);
}
}