use crate::document::CadDocument;
use crate::entities::Viewport;
use crate::types::Vector3;
use crate::xdata::{ExtendedDataRecord, XDataValue as X};
fn mview_range(values: &[X]) -> Option<std::ops::Range<usize>> {
for start in 0..values.len().saturating_sub(1) {
if !matches!(&values[start], X::String(name) if name == "MVIEW")
|| !matches!(&values[start + 1], X::ControlString(s) if s == "{")
{
continue;
}
let mut depth = 0;
for (index, value) in values.iter().enumerate().skip(start + 1) {
match value {
X::ControlString(s) if s == "{" => depth += 1,
X::ControlString(s) if s == "}" => {
depth -= 1;
if depth == 0 {
return Some(start..index + 1);
}
}
_ => {}
}
}
}
None
}
pub(crate) fn record(v: &Viewport, document: &CadDocument) -> ExtendedDataRecord {
let mut values = vec![
X::String("MVIEW".into()),
X::ControlString("{".into()),
X::Integer16(16),
X::Point3D(v.view_target),
X::Point3D(v.view_direction),
X::Real(v.twist_angle.to_degrees()),
X::Real(v.view_height),
X::Real(v.view_center.x),
X::Real(v.view_center.y),
X::Real(v.lens_length),
X::Real(v.front_clip_z),
X::Real(v.back_clip_z),
X::Integer16((v.status.to_bits() & 0x1F) as i16),
X::Integer16(v.circle_sides),
X::Integer16(v.status.fast_zoom as i16),
X::Integer16(v.ucs_icon_visible as i16 | ((v.ucs_at_origin as i16) << 1)),
X::Integer16(v.status.snap_on as i16),
X::Integer16(v.status.grid_on as i16),
X::Integer16(v.status.isometric_snap as i16),
X::Integer16(if v.status.iso_pair_right {
2
} else if v.status.iso_pair_top {
1
} else {
0
}),
X::Real(v.snap_angle.to_degrees()),
X::Real(v.snap_base.x),
X::Real(v.snap_base.y),
X::Real(v.snap_spacing.x),
X::Real(v.snap_spacing.y),
X::Real(v.grid_spacing.x),
X::Real(v.grid_spacing.y),
X::Integer16(v.status.hide_plot as i16),
X::ControlString("{".into()),
];
for layer in document
.layers
.iter()
.filter(|layer| v.frozen_layers.contains(&layer.handle))
{
values.push(X::LayerName(layer.name.clone()));
}
values.extend([X::ControlString("}".into()), X::ControlString("}".into())]);
let mut record = v
.common
.extended_data
.records()
.iter()
.find(|record| record.application_name.eq_ignore_ascii_case("ACAD"))
.cloned()
.unwrap_or_else(|| ExtendedDataRecord::new("ACAD"));
if let Some(range) = mview_range(&record.values) {
record.values.splice(range, values);
} else {
record.values.extend(values);
}
record
}
pub(crate) fn restore(v: &mut Viewport, layer_handle: impl Fn(&str) -> Option<crate::Handle>) {
restore_impl(v, layer_handle, false);
}
pub(crate) fn restore_r12(v: &mut Viewport, layer_handle: impl Fn(&str) -> Option<crate::Handle>) {
restore_impl(v, layer_handle, true);
}
pub(crate) fn record_r12(v: &Viewport, document: &CadDocument) -> ExtendedDataRecord {
let mut result = record(v, document);
if let Some(range) = mview_range(&result.values) {
result.values[range.start + 5] = X::Real(v.twist_angle);
result.values[range.start + 20] = X::Real(v.snap_angle);
}
result
}
fn restore_impl(
v: &mut Viewport,
layer_handle: impl Fn(&str) -> Option<crate::Handle>,
radians: bool,
) {
let Some(record) = v
.common
.extended_data
.records()
.iter()
.find(|record| record.application_name.eq_ignore_ascii_case("ACAD"))
else {
return;
};
let Some(range) = mview_range(&record.values) else {
return;
};
let values = &record.values[range.start + 1..range.end];
if values.len() < 30
|| !matches!(&values[0], X::ControlString(s) if s == "{")
|| !matches!(&values[1], X::Integer16(16))
|| !matches!(&values[2], X::Point3D(_))
|| !matches!(&values[3], X::Point3D(_))
|| !matches!(&values[27], X::ControlString(s) if s == "{")
|| !values[4..11]
.iter()
.all(|value| matches!(value, X::Real(_)))
|| !values[11..19]
.iter()
.all(|value| matches!(value, X::Integer16(_)))
|| !values[19..26]
.iter()
.all(|value| matches!(value, X::Real(_)))
|| !matches!(&values[26], X::Integer16(_))
{
return;
}
let real = |i: usize| {
if let X::Real(v) = values[i + 2] {
v
} else {
0.0
}
};
let int = |i: usize| {
if let X::Integer16(v) = values[i + 2] {
v
} else {
0
}
};
let point = |i: usize| {
if let X::Point3D(v) = values[i + 2] {
v
} else {
Vector3::ZERO
}
};
v.view_target = point(0);
v.view_direction = point(1);
v.twist_angle = if radians {
real(2)
} else {
real(2).to_radians()
};
v.view_height = real(3);
if v.view_height.is_finite() && v.view_height > 0.0 {
v.custom_scale = v.height / v.view_height;
}
v.view_center = Vector3::new(real(4), real(5), 0.0);
v.lens_length = real(6);
v.front_clip_z = real(7);
v.back_clip_z = real(8);
v.status = crate::entities::ViewportStatusFlags::from_bits(int(9) as i32 | 0x8000);
v.circle_sides = int(10);
v.status.fast_zoom = int(11) != 0;
v.ucs_icon_visible = int(12) & 1 != 0;
v.ucs_at_origin = int(12) & 2 != 0;
v.status.snap_on = int(13) != 0;
v.status.grid_on = int(14) != 0;
v.status.isometric_snap = int(15) != 0;
v.snap_angle = if radians {
real(17)
} else {
real(17).to_radians()
};
v.status.iso_pair_top = int(16) == 1;
v.status.iso_pair_right = int(16) == 2;
v.snap_base = Vector3::new(real(18), real(19), 0.0);
v.snap_spacing = Vector3::new(real(20), real(21), 0.0);
v.grid_spacing = Vector3::new(real(22), real(23), 0.0);
v.status.hide_plot = int(24) != 0;
v.frozen_layers = values[28..]
.iter()
.take_while(|value| !matches!(value, X::ControlString(s) if s == "}"))
.filter_map(|value| {
if let X::LayerName(name) = value {
layer_handle(name)
} else {
None
}
})
.collect();
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn mview_update_preserves_unrelated_application_values() {
let doc = CadDocument::new();
let mut viewport = Viewport::new();
let mut original = record(&viewport, &doc);
original.values.insert(0, X::Integer32(123));
original.values.push(X::String("OTHER".into()));
viewport.common.extended_data.add_record(original);
viewport.view_height = 77.;
let updated = record(&viewport, &doc);
assert_eq!(updated.values.first(), Some(&X::Integer32(123)));
assert_eq!(updated.values.last(), Some(&X::String("OTHER".into())));
assert_eq!(
updated
.values
.iter()
.filter(|v| matches!(v,X::String(s) if s=="MVIEW"))
.count(),
1
);
viewport.common.extended_data.upsert_record(updated);
viewport.view_height = 0.;
restore(&mut viewport, |_| None);
assert_eq!(viewport.view_height, 77.);
}
#[test]
fn truncated_mview_does_not_change_viewport() {
let mut viewport = Viewport::new();
let mut data = ExtendedDataRecord::new("ACAD");
data.values = vec![X::String("MVIEW".into()), X::ControlString("{".into())];
viewport.common.extended_data.add_record(data);
let expected = viewport.clone();
restore(&mut viewport, |_| None);
assert_eq!(viewport, expected);
}
#[test]
fn plain_mview_string_does_not_consume_unrelated_data() {
let doc = CadDocument::new();
let mut viewport = Viewport::new();
let mut data = ExtendedDataRecord::new("ACAD");
data.values = vec![X::String("MVIEW".into()), X::Integer32(123)];
viewport.common.extended_data.add_record(data.clone());
let updated = record(&viewport, &doc);
assert_eq!(updated.values[..2], data.values);
viewport.common.extended_data.upsert_record(updated);
viewport.view_height = 0.;
restore(&mut viewport, |_| None);
assert_eq!(viewport.view_height, Viewport::new().view_height);
}
#[test]
fn malformed_mview_scalar_does_not_reset_view_parameters() {
let doc = CadDocument::new();
let mut viewport = Viewport::new();
let mut data = record(&viewport, &doc);
data.values[7] = X::Integer32(123);
viewport.common.extended_data.add_record(data);
let expected = viewport.clone();
restore(&mut viewport, |_| None);
assert_eq!(viewport, expected);
}
}