Files
OneCAD-Draft/src/scene/pipeline/wire_arena.rs
T

1502 lines
53 KiB
Rust

// Persistent per-entity wire instance arena with storage and packed adapters.
//
// The normal wire path re-emits EVERY wire into a fresh instance buffer whenever
// the resident set's content id changes — so any edit on a drawing whose wires
// expand to millions of segments re-uploads the whole (hundreds-of-MB) buffer,
// which stalls for ~1s on a shared-memory GPU. This arena instead keeps one
// persistent instance buffer (plus its shared WireConst storage) laid out as
// per-entity *slabs*, so an edit only writes what changed:
//
// * Modify in place — a move / rotate / scale / colour change keeps the
// entity's segment count, so its slab is overwritten where it sits.
// * Add — bump-allocate a fresh slab at the tail.
// * A tail Modify whose segment count changed — resize its terminal slab in
// place. A non-tail shape change rejects the patch before touching GPU state
// so the caller can rebuild this wire arena cleanly.
// * Erase — tombstone the slab (blank instances that render nothing).
//
// Two correctness points make add/remove safe:
// * draw_depth_map uses stable sparse labels, so Add/Remove changes only the
// named entity's depth. Existing slabs retain their WireConst values and no
// whole-const-buffer upload is needed.
// * A tail-appended entity draws last, which only mis-orders alpha-blended /
// coincident wires. So when the set contains ANY transparent wire we bail to a
// full rebuild instead of appending. Opaque overlap resolves by the z-bias, so
// it is order-independent and safe to relocate.
//
// A tombstoned instance points at const slot 0, whose negative pattern length
// is a shader-level discard sentinel. When tombstone waste or capacity is
// exceeded, `patch` returns false and the caller compacts via a full rebuild.
// Because a full rebuild is always the fallback, correctness never rides on the
// fast path.
//
// Scope: a SINGLE batch — the set must have no mesh-edge fills (which force the
// draw-order-preserving multi-batch split) and no per-wire scissor (paper content
// viewports). Mixed 2D/3D or scissored sets fall back to the batched path.
use super::wire_gpu::{
emit_wire_native, emit_wire_packed, wire_draw_depth, PackedWireInstance, WireConst, WireGpu,
WireInstance,
};
use crate::scene::model::wire_model::WireModel;
use crate::scene::ChangeKind;
use acadrust::Handle;
use iced::wgpu;
use rustc_hash::FxHashMap;
/// Spare capacity multiplier when (re)allocating, so a run of adds appends
/// without reallocating each time.
const HEADROOM_NUM: u64 = 3;
const HEADROOM_DEN: u64 = 2;
const MIN_INST_CAP: u64 = 4096;
const MIN_CONST_CAP: u64 = 1024;
/// wgpu caps a single buffer at 256 MB. An arena keeps ONE instance buffer per
/// batch, so a batch whose instances exceed this can't be an arena — build
/// returns None and the caller falls back to the chunked batched path. The
/// buffer (with headroom) is also clamped here so it never exceeds the limit.
const MAX_INSTANCES: u64 = 268_435_456 / std::mem::size_of::<WireInstance>() as u64;
const MAX_CONSTS: u64 = 268_435_456 / std::mem::size_of::<WireConst>() as u64;
struct Slab {
inst_off: u32,
inst_len: u32,
const_off: u32,
const_len: u32,
/// World-XY bounds for plan-view draw-range culling. Unbounded whenever a
/// source wire does not carry a trustworthy entity AABB.
aabb: [f32; 4],
/// Entity-level draw depth used when this slab was emitted. Individual
/// consts may carry block-local offsets around it; structural edits shift
/// the whole slab by the base-depth delta instead of flattening those
/// offsets.
base_depth: f32,
}
struct PreparedPatchRun {
insts: Vec<WireInstance>,
csts: Vec<WireConst>,
base_depth: f32,
aabb: [f32; 4],
order_sensitive: bool,
}
fn can_resize_terminal_slab(
slab: &Slab,
inst_tail: u32,
const_tail: u32,
inst_cap: u32,
const_cap: u32,
new_inst_len: u32,
new_const_len: u32,
change_count: usize,
) -> bool {
change_count == 1
&& slab.inst_off + slab.inst_len == inst_tail
&& slab.const_off + slab.const_len == const_tail
&& slab.inst_off + new_inst_len <= inst_cap
&& slab.const_off + new_const_len <= const_cap
}
pub struct WireArena {
inst_buf: wgpu::Buffer,
inst_cap: u32,
inst_tail: u32,
const_buf: wgpu::Buffer,
const_bind_group: std::sync::Arc<wgpu::BindGroup>,
const_cap: u32,
const_tail: u32,
/// CPU mirror of the const buffer, used for in-place tail resize/patches.
consts_cpu: Vec<WireConst>,
slabs: FxHashMap<Handle, Slab>,
/// Temporarily hidden Modified slabs. Grip drag blanks these but keeps their
/// offsets so commit/cancel can restore the original submission order.
vacant: FxHashMap<Handle, Slab>,
/// Tombstoned instances (blanked, not reclaimed) — past half the tail a patch
/// bails so the caller compacts with a full rebuild.
tombstoned: u32,
/// Whether this arena's wires are 3D mesh/solid edges (`is_3d_mesh_edge` on
/// the draw batch): the draw loop hides them in clean-shaded modes and draws
/// them black in filled-with-edges modes. The regular and mesh-edge subsets
/// of the resident set each get their own arena so both patch incrementally.
mesh_edge: bool,
/// Conservative submission-order sensitivity of current arena content.
order_sensitive: bool,
}
fn handle_of(w: &WireModel) -> Option<Handle> {
crate::scene::Scene::handle_from_wire_name(&w.name)
}
/// True when `w` needs the shaded-mode edge treatment.
pub fn is_mesh_edge(w: &WireModel, _mesh_names: &rustc_hash::FxHashSet<u64>) -> bool {
!w.points.is_empty() && w.fill_is_3d
}
/// True when appending a new entity at the tail could change the image, so the
/// arena must fall back to a full rebuild instead of relocating a slab. Two
/// cases where draw order (not the z-bias) decides the winning pixel:
/// * transparency — alpha blends in submission order;
/// * a wire with NO draw-order depth — 3D solids (Solid3D / Region / Body /
/// Surface) are excluded from `draw_depth_map`, so their fallback edge wires
/// get draw_depth 0.0. Two coincident opaque such wires share a z-bias and
/// resolve by submission order, which a tail relocation would flip.
fn order_sensitive(wires: &[&WireModel], depth_map: &FxHashMap<u64, [f32; 2]>) -> bool {
wires.iter().any(|w| {
w.color[3] < 0.999
|| handle_of(w).map_or(true, |h| !depth_map.contains_key(&h.value()))
})
}
/// handle → wire-slot index for the selection / text-highlight overlays, built
/// from the resident Vec (independent of the arena's slab layout).
pub fn build_handle_index(wires: &[WireModel]) -> std::sync::Arc<FxHashMap<u64, Vec<u32>>> {
let mut index: FxHashMap<u64, Vec<u32>> = FxHashMap::default();
index.reserve(wires.len());
for (idx, w) in wires.iter().enumerate() {
if let Ok(h) = w.name.parse::<u64>() {
index.entry(h).or_default().push(idx as u32);
}
}
std::sync::Arc::new(index)
}
/// Apply the resident Vec's exact splice operations to the selection/text
/// handle index. Avoids reparsing every wire name after a one-entity patch.
pub(crate) fn patch_handle_index(
index: &mut std::sync::Arc<FxHashMap<u64, Vec<u32>>>,
edits: &[crate::scene::WireIndexEdit],
) {
let index = std::sync::Arc::make_mut(index);
for edit in edits {
index.remove(&edit.handle.value());
let old_end = edit.start + edit.old_len;
let delta = edit.new_len as isize - edit.old_len as isize;
if delta != 0 {
for slots in index.values_mut() {
for slot in slots {
if *slot as usize >= old_end {
*slot = (*slot as isize + delta) as u32;
}
}
}
}
if edit.visible && edit.new_len != 0 {
index.insert(
edit.handle.value(),
(edit.start..edit.start + edit.new_len)
.map(|slot| slot as u32)
.collect(),
);
}
}
}
/// Group `wires` (draw-order sorted, entity-contiguous) into per-handle ranges.
fn handle_ranges(wires: &[&WireModel]) -> Option<Vec<(Handle, usize, usize)>> {
let mut out: Vec<(Handle, usize, usize)> = Vec::new();
let mut i = 0;
while i < wires.len() {
let h = handle_of(wires[i])?;
let mut j = i + 1;
while j < wires.len() && handle_of(wires[j]) == Some(h) {
j += 1;
}
out.push((h, i, j));
i = j;
}
Some(out)
}
fn run_aabb(wires: &[&WireModel]) -> [f32; 4] {
let mut out = [
f32::INFINITY,
f32::INFINITY,
f32::NEG_INFINITY,
f32::NEG_INFINITY,
];
for wire in wires {
let [x0, y0, x1, y1] = wire.aabb;
if !x0.is_finite()
|| !y0.is_finite()
|| !x1.is_finite()
|| !y1.is_finite()
|| x0 > x1
|| y0 > y1
{
return WireModel::UNBOUNDED_AABB;
}
let pad = (wire.world_width * 0.5).max(0.0);
out[0] = out[0].min(x0 - pad);
out[1] = out[1].min(y0 - pad);
out[2] = out[2].max(x1 + pad);
out[3] = out[3].max(y1 + pad);
}
if out[0].is_finite() {
out
} else {
WireModel::UNBOUNDED_AABB
}
}
fn make_const_bg(
device: &wgpu::Device,
bgl: &wgpu::BindGroupLayout,
buf: &wgpu::Buffer,
) -> std::sync::Arc<wgpu::BindGroup> {
std::sync::Arc::new(device.create_bind_group(&wgpu::BindGroupDescriptor {
label: Some("wire_arena.const.bg"),
layout: bgl,
entries: &[wgpu::BindGroupEntry {
binding: 0,
resource: buf.as_entire_binding(),
}],
}))
}
fn alloc_inst_initialized(
device: &wgpu::Device,
cap: u64,
data: &[WireInstance],
) -> wgpu::Buffer {
let buffer = device.create_buffer(&wgpu::BufferDescriptor {
label: Some("wire_arena.ibuf"),
size: cap * std::mem::size_of::<WireInstance>() as u64,
usage: wgpu::BufferUsages::VERTEX | wgpu::BufferUsages::COPY_DST,
mapped_at_creation: true,
});
if !data.is_empty() {
let bytes = bytemuck::cast_slice(data);
let mut mapped = buffer
.slice(..bytes.len() as u64)
.get_mapped_range_mut();
mapped.copy_from_slice(bytes);
drop(mapped);
}
buffer.unmap();
buffer
}
fn alloc_const_initialized(
device: &wgpu::Device,
cap: u64,
data: &[WireConst],
) -> wgpu::Buffer {
let buffer = device.create_buffer(&wgpu::BufferDescriptor {
label: Some("wire_arena.cbuf"),
size: cap * std::mem::size_of::<WireConst>() as u64,
usage: wgpu::BufferUsages::STORAGE | wgpu::BufferUsages::COPY_DST,
mapped_at_creation: true,
});
if !data.is_empty() {
let bytes = bytemuck::cast_slice(data);
let mut mapped = buffer
.slice(..bytes.len() as u64)
.get_mapped_range_mut();
mapped.copy_from_slice(bytes);
drop(mapped);
}
buffer.unmap();
buffer
}
fn blank_const() -> WireConst {
let mut blank = <WireConst as bytemuck::Zeroable>::zeroed();
// Negative pattern length is reserved for arena tombstones. A zero-length
// segment still expands to a half-pixel when LWDISPLAY is off, so geometry
// alone cannot make a tombstone invisible.
blank.pattern_length = -1.0;
blank
}
/// A tombstoned instance. Const slot 0 carries the shader discard sentinel.
fn blank_instance() -> WireInstance {
WireInstance {
pos_a: [0.0; 3],
pos_a_low: [0.0; 3],
pos_b: [0.0; 3],
pos_b_low: [0.0; 3],
distance_a: 0.0,
distance_b: 0.0,
wire_id: 0,
taper_ratio: [0; 2],
}
}
impl WireArena {
/// Build a fresh arena from the full resident set, or `None` if it isn't a
/// single scissor-free batch or a wire is unnamed (caller keeps the batched
/// path).
pub fn build(
device: &wgpu::Device,
_queue: &wgpu::Queue,
wires: &[&WireModel],
depth_map: &FxHashMap<u64, [f32; 2]>,
const_bgl: &wgpu::BindGroupLayout,
mesh_edge: bool,
) -> Option<Self> {
let ranges = handle_ranges(wires)?;
let perf = crate::perf::enabled();
let total_started = iced::time::Instant::now();
// Reject an oversized batch before parallel emission allocates hundreds
// of megabytes. `points.len() - 1` is an upper bound because NaN-break
// segments are skipped by emit_wire_native.
let max_instances: usize = wires
.iter()
.map(|w| w.points.len().saturating_sub(1))
.sum();
if max_instances as u64 > MAX_INSTANCES || wires.len() as u64 + 1 > MAX_CONSTS {
return None;
}
struct BuildPlan {
handle: Handle,
start: usize,
end: usize,
const_off: u32,
base_depth: f32,
}
struct PackedSlab {
handle: Handle,
const_off: u32,
base_depth: f32,
aabb: [f32; 4],
instances: Vec<WireInstance>,
consts: Vec<WireConst>,
}
// Assign global const slots serially so parallel workers can emit final
// wire_id values directly. Indexed parallel collect preserves handle and
// wire submission order.
let mut next_const = 1u32;
let plans: Vec<BuildPlan> = ranges
.into_iter()
.map(|(handle, start, end)| {
let const_off = next_const;
next_const += (end - start) as u32;
let base_depth = if mesh_edge {
0.0
} else {
depth_map.get(&handle.value()).map_or(0.0, |d| d[0])
};
BuildPlan {
handle,
start,
end,
const_off,
base_depth,
}
})
.collect();
let pack_started = iced::time::Instant::now();
use crate::par::prelude::*;
let packed: Vec<PackedSlab> = plans
.par_iter()
.map(|plan| {
let run = &wires[plan.start..plan.end];
let capacity: usize = run
.iter()
.map(|w| w.points.len().saturating_sub(1))
.sum();
let mut instances: Vec<WireInstance> = Vec::with_capacity(capacity);
let mut consts: Vec<WireConst> = Vec::with_capacity(run.len());
for (local, &w) in run.iter().enumerate() {
let wire_id = plan.const_off + local as u32;
// 3D mesh outline edges are occluded by true depth and must NOT
// take the draw-order z-bias (or hidden back edges peek through
// the shaded fill) — matching WireGpu::from_run.
let dd = if mesh_edge { 0.0 } else { wire_draw_depth(w, depth_map) };
let (mut emitted, cst) = emit_wire_native(w, wire_id, w.color, dd);
instances.append(&mut emitted);
consts.push(cst);
}
PackedSlab {
handle: plan.handle,
const_off: plan.const_off,
base_depth: plan.base_depth,
aabb: run_aabb(run),
instances,
consts,
}
})
.collect();
let pack_ms = pack_started.elapsed().as_secs_f64() * 1000.0;
let inst_count: usize = packed.iter().map(|slab| slab.instances.len()).sum();
let const_count: usize = 1 + packed.iter().map(|slab| slab.consts.len()).sum::<usize>();
if inst_count as u64 > MAX_INSTANCES || const_count as u64 > MAX_CONSTS {
return None;
}
// const slot 0 = blank tombstone target.
let mut instances: Vec<WireInstance> = Vec::with_capacity(inst_count);
let mut consts_cpu: Vec<WireConst> = Vec::with_capacity(const_count);
consts_cpu.push(blank_const());
let mut slabs: FxHashMap<Handle, Slab> =
FxHashMap::with_capacity_and_hasher(packed.len(), Default::default());
for mut packed_slab in packed {
let inst_off = instances.len() as u32;
let inst_len = packed_slab.instances.len() as u32;
let const_len = packed_slab.consts.len() as u32;
instances.append(&mut packed_slab.instances);
consts_cpu.append(&mut packed_slab.consts);
slabs.insert(
packed_slab.handle,
Slab {
inst_off,
inst_len,
const_off: packed_slab.const_off,
const_len,
aabb: packed_slab.aabb,
base_depth: packed_slab.base_depth,
},
);
}
let inst_tail = instances.len() as u32;
let const_tail = consts_cpu.len() as u32;
// A batch bigger than one buffer can't be an arena — let the caller chunk
// it via the batched path.
if inst_tail as u64 > MAX_INSTANCES || const_tail as u64 > MAX_CONSTS {
return None;
}
let inst_cap = ((inst_tail as u64 * HEADROOM_NUM / HEADROOM_DEN)
.max(MIN_INST_CAP)
.min(MAX_INSTANCES)) as u32;
let const_cap = ((const_tail as u64 * HEADROOM_NUM / HEADROOM_DEN)
.max(MIN_CONST_CAP)
.min(MAX_CONSTS)) as u32;
let upload_started = iced::time::Instant::now();
let inst_buf = alloc_inst_initialized(device, inst_cap as u64, &instances);
let const_buf = alloc_const_initialized(device, const_cap as u64, &consts_cpu);
let upload_ms = upload_started.elapsed().as_secs_f64() * 1000.0;
let const_bind_group = make_const_bg(device, const_bgl, &const_buf);
if perf {
crate::perf_record!(
"[perf] arena-build-detail total={:.1}ms pack={:.1} mapped-upload={:.1} handles={} wires={} instances={} instance-bytes={} consts={}",
total_started.elapsed().as_secs_f64() * 1000.0,
pack_ms,
upload_ms,
slabs.len(),
wires.len(),
inst_tail,
inst_tail as usize * std::mem::size_of::<WireInstance>(),
const_tail,
);
}
Some(Self {
inst_buf,
inst_cap,
inst_tail,
const_buf,
const_bind_group,
const_cap,
const_tail,
consts_cpu,
slabs,
vacant: FxHashMap::default(),
tombstoned: 0,
mesh_edge,
order_sensitive: order_sensitive(wires, depth_map),
})
}
fn write_insts(&self, queue: &wgpu::Queue, off: u32, data: &[WireInstance]) {
if data.is_empty() {
return;
}
let sz = std::mem::size_of::<WireInstance>() as u64;
queue.write_buffer(&self.inst_buf, off as u64 * sz, bytemuck::cast_slice(data));
}
/// Apply the changed handles in place; returns false (⇒ full rebuild) when the
/// arena can't absorb the change: not eligible, a transparent append, a
/// capacity overflow, or too much tombstone waste.
pub fn patch(
&mut self,
queue: &wgpu::Queue,
changes: &[(Handle, ChangeKind)],
runs: &FxHashMap<Handle, Vec<&WireModel>>,
new_handles_are_suffix: bool,
depth_map: &FxHashMap<u64, [f32; 2]>,
) -> bool {
// Prepare and validate every visible run before mutating either GPU
// buffer. Growing/shrinking a Modified slab used to tombstone the old
// range and append a new one. Repeated live-polyline updates could then
// leave the arena half-patched when a later guard requested a rebuild,
// producing alternating old/new submissions. The terminal slab can
// grow/shrink without relocation (the common live-polyline case);
// other shape changes take the clean full-arena fallback while the
// scene itself still re-tessellates only the named entity.
let mut prepared: FxHashMap<Handle, PreparedPatchRun> = FxHashMap::default();
for &(h, kind) in changes {
let run = runs.get(&h).map(Vec::as_slice).unwrap_or(&[]);
if matches!(kind, ChangeKind::Removed) || run.is_empty() {
continue;
}
let mut insts: Vec<WireInstance> = Vec::new();
let mut csts: Vec<WireConst> = Vec::new();
for &w in run {
let wire_id = csts.len() as u32;
let dd = if self.mesh_edge {
0.0
} else {
wire_draw_depth(w, depth_map)
};
let (mut wi, c) = emit_wire_native(w, wire_id, w.color, dd);
insts.append(&mut wi);
csts.push(c);
}
let inst_len = insts.len() as u32;
let const_len = csts.len() as u32;
if matches!(kind, ChangeKind::Modified) {
let known = self.slabs.get(&h).or_else(|| self.vacant.get(&h));
let shape_changed = known
.is_some_and(|slab| slab.inst_len != inst_len || slab.const_len != const_len);
let can_resize_tail = self.slabs.get(&h).is_some_and(|slab| {
can_resize_terminal_slab(
slab,
self.inst_tail,
self.const_tail,
self.inst_cap,
self.const_cap,
inst_len,
const_len,
changes.len(),
)
});
if shape_changed && !can_resize_tail {
return false;
}
}
prepared.insert(
h,
PreparedPatchRun {
insts,
csts,
base_depth: if self.mesh_edge {
0.0
} else {
depth_map.get(&h.value()).map_or(0.0, |d| d[0])
},
aabb: run_aabb(run),
order_sensitive: order_sensitive(run, depth_map),
},
);
}
for &(h, kind) in changes {
let run = runs.get(&h).map(Vec::as_slice).unwrap_or(&[]);
// Removed / now-hidden ⇒ tombstone the slab. A handle not in THIS
// arena's subset (it belongs to the other batch) simply isn't in its
// slabs, so this is a no-op for it.
if matches!(kind, ChangeKind::Removed) || run.is_empty() {
if let Some(slab) = self.slabs.remove(&h) {
let blanks = vec![blank_instance(); slab.inst_len as usize];
self.write_insts(queue, slab.inst_off, &blanks);
self.tombstoned += slab.inst_len;
if matches!(kind, ChangeKind::Modified) {
self.vacant.insert(h, slab);
}
}
if matches!(kind, ChangeKind::Removed) {
self.vacant.remove(&h);
}
continue;
}
let PreparedPatchRun {
mut insts,
csts,
base_depth,
aabb,
order_sensitive: run_order_sensitive,
} = prepared
.remove(&h)
.expect("visible wire patch run was prepared");
let inst_len = insts.len() as u32;
let const_len = csts.len() as u32;
if !self.slabs.contains_key(&h)
&& self
.vacant
.get(&h)
.is_some_and(|s| s.inst_len == inst_len && s.const_len == const_len)
{
let slab = self.vacant.remove(&h).unwrap();
self.tombstoned = self.tombstoned.saturating_sub(slab.inst_len);
self.slabs.insert(h, slab);
}
let in_place = self
.slabs
.get(&h)
.map(|s| s.inst_len == inst_len && s.const_len == const_len)
.unwrap_or(false);
if in_place {
let (inst_off, const_off) = {
let s = self.slabs.get(&h).unwrap();
(s.inst_off, s.const_off)
};
for w in insts.iter_mut() {
w.wire_id += const_off;
}
self.write_insts(queue, inst_off, &insts);
for (k, c) in csts.iter().enumerate() {
self.consts_cpu[const_off as usize + k] = *c;
}
// Push the entity's consts to the GPU too — an in-place edit is
// NOT structural, so the whole-buffer refresh below won't run and
// a colour change would otherwise never reach the shader.
let csz = std::mem::size_of::<WireConst>() as u64;
queue.write_buffer(
&self.const_buf,
const_off as u64 * csz,
bytemuck::cast_slice(&csts),
);
let slab = self.slabs.get_mut(&h).unwrap();
slab.base_depth = base_depth;
slab.aabb = aabb;
continue;
}
// A live entity is normally the newest handle and therefore owns
// the terminal slab. Resize that slab at the same offsets instead
// of tombstoning it and rebuilding the whole arena as its segment
// count grows on every click.
let can_resize_tail = self.slabs.get(&h).is_some_and(|slab| {
can_resize_terminal_slab(
slab,
self.inst_tail,
self.const_tail,
self.inst_cap,
self.const_cap,
inst_len,
const_len,
changes.len(),
)
});
if can_resize_tail {
let (inst_off, const_off) = {
let slab = self.slabs.get(&h).unwrap();
(slab.inst_off, slab.const_off)
};
for instance in &mut insts {
instance.wire_id += const_off;
}
self.write_insts(queue, inst_off, &insts);
self.consts_cpu.truncate(const_off as usize);
self.consts_cpu.extend(csts.iter().copied());
let csz = std::mem::size_of::<WireConst>() as u64;
queue.write_buffer(
&self.const_buf,
const_off as u64 * csz,
bytemuck::cast_slice(&csts),
);
self.inst_tail = inst_off + inst_len;
self.const_tail = const_off + const_len;
let slab = self.slabs.get_mut(&h).unwrap();
slab.inst_len = inst_len;
slab.const_len = const_len;
slab.base_depth = base_depth;
slab.aabb = aabb;
self.order_sensitive |= run_order_sensitive;
continue;
}
// Layout changed ⇒ append at the tail. Unsafe to relocate when the set
// resolves overlap by submission order: transparency, a wire with no
// draw-order depth, or the mesh-edge arena (all its wires are forced
// to depth 0, so coincident edges resolve by submission order). Fall
// back to a full rebuild instead.
let is_new = !self.slabs.contains_key(&h);
let preserves_submission_order = is_new && new_handles_are_suffix;
if (self.order_sensitive || run_order_sensitive || self.mesh_edge)
&& !preserves_submission_order
{
return false;
}
if self.inst_tail + inst_len > self.inst_cap
|| self.const_tail + const_len > self.const_cap
{
return false;
}
self.vacant.remove(&h);
if let Some(s) = self.slabs.remove(&h) {
let blanks = vec![blank_instance(); s.inst_len as usize];
self.write_insts(queue, s.inst_off, &blanks);
self.tombstoned += s.inst_len;
}
let inst_off = self.inst_tail;
let const_off = self.const_tail;
for w in insts.iter_mut() {
w.wire_id += const_off;
}
self.write_insts(queue, inst_off, &insts);
for c in &csts {
self.consts_cpu.push(*c);
}
// Appended instances immediately reference these constant slots.
// Keep the GPU buffer in sync without relying on a full-scene upload.
if !csts.is_empty() {
let const_size = std::mem::size_of::<WireConst>() as u64;
queue.write_buffer(
&self.const_buf,
const_off as u64 * const_size,
bytemuck::cast_slice(&csts),
);
}
self.inst_tail += inst_len;
self.const_tail += const_len;
self.slabs.insert(
h,
Slab {
inst_off,
inst_len,
const_off,
const_len,
aabb,
base_depth,
},
);
self.order_sensitive |= run_order_sensitive;
}
if self.tombstoned > self.inst_tail / 2 {
return false;
}
true
}
/// One draw batch wrapping the persistent instance buffer. `instance_count`
/// is the whole tail (tombstones included — they draw nothing).
pub fn wire_gpus(&self) -> Vec<WireGpu> {
if self.inst_tail == 0 {
return vec![];
}
vec![WireGpu {
instance_buffer: self.inst_buf.clone(),
first_instance: 0,
instance_count: self.inst_tail,
is_3d_mesh_edge: self.mesh_edge,
const_bind_group: Some(self.const_bind_group.clone()),
}]
}
/// Draw only plan-view entity ranges that can reach the viewport. The
/// instance buffer stays fully resident, so pan/zoom changes only this tiny
/// list of offsets — no repack and no GPU upload. Non-plan views use the
/// conservative full draw because a 2-D entity AABB does not contain Z.
pub fn wire_gpus_visible(
&self,
view_rot: glam::Mat4,
eye: glam::DVec3,
clip_w: u32,
clip_h: u32,
) -> Vec<WireGpu> {
let perf = crate::perf::enabled();
let perf_started = perf.then(iced::time::Instant::now);
if self.inst_tail == 0 {
return vec![];
}
let projected_x = view_rot.transform_vector3(glam::Vec3::X);
let projected_y = view_rot.transform_vector3(glam::Vec3::Y);
let projected_z = view_rot.transform_vector3(glam::Vec3::Z);
let xy_scale = projected_x
.truncate()
.length()
.max(projected_y.truncate().length())
.max(f32::MIN_POSITIVE);
if projected_z.truncate().length() > xy_scale * 1e-5 {
return self.wire_gpus();
}
let mut ranges: Vec<(u32, u32)> = self
.slabs
.values()
.filter(|slab| {
slab.inst_len > 0
&& !super::aabb_offscreen(slab.aabb, view_rot, eye, clip_w, clip_h)
})
.map(|slab| (slab.inst_off, slab.inst_off + slab.inst_len))
.collect();
ranges.sort_unstable_by_key(|range| range.0);
let mut merged: Vec<(u32, u32)> = Vec::with_capacity(ranges.len());
for (start, end) in ranges {
if let Some((_, previous_end)) = merged.last_mut() {
if *previous_end == start {
*previous_end = end;
continue;
}
}
merged.push((start, end));
}
let mut ranges = merged;
if ranges.is_empty() {
return vec![];
}
// Cap CPU draw-call overhead on pathologically interleaved draw order.
// Merging a few separated visible spans draws their offscreen gap too,
// but retains order and still avoids the rest of a multi-million
// instance drawing.
const MAX_RANGES: usize = 64;
if ranges.len() > MAX_RANGES {
let group = (ranges.len() + MAX_RANGES - 1) / MAX_RANGES;
ranges = ranges
.chunks(group)
.map(|chunk| (chunk[0].0, chunk[chunk.len() - 1].1))
.collect();
}
if perf {
let submitted: u64 = ranges
.iter()
.map(|(start, end)| (end - start) as u64)
.sum();
let elapsed_ms = perf_started
.map(|started| started.elapsed().as_secs_f64() * 1000.0)
.unwrap_or_default();
if submitted < self.inst_tail as u64 || elapsed_ms >= 1.0 {
crate::perf_record!(
"[perf] wire-cull {:>7.1}ms submitted={} resident={} ranges={}",
elapsed_ms,
submitted,
self.inst_tail,
ranges.len(),
);
}
}
ranges
.into_iter()
.map(|(start, end)| WireGpu {
instance_buffer: self.inst_buf.clone(),
first_instance: start,
instance_count: end - start,
is_3d_mesh_edge: self.mesh_edge,
const_bind_group: Some(self.const_bind_group.clone()),
})
.collect()
}
}
// ── Packed arena adapter ───────────────────────────────────────────────────
/// Persistent arena for devices without vertex-stage storage buffers. Shared
/// wire constants stay duplicated in each packed instance, but residency,
/// entity-local patches, tombstones, headroom, and visibility ranges match the
/// indexed-storage arena above.
struct PackedWireArena {
inst_buf: wgpu::Buffer,
inst_cap: u32,
inst_tail: u32,
slabs: FxHashMap<Handle, Slab>,
vacant: FxHashMap<Handle, Slab>,
tombstoned: u32,
mesh_edge: bool,
order_sensitive: bool,
}
struct PreparedPackedPatchRun {
insts: Vec<PackedWireInstance>,
base_depth: f32,
aabb: [f32; 4],
order_sensitive: bool,
}
const MAX_PACKED_INSTANCES: u64 =
268_435_456 / std::mem::size_of::<PackedWireInstance>() as u64;
fn blank_packed_instance() -> PackedWireInstance {
let mut blank = <PackedWireInstance as bytemuck::Zeroable>::zeroed();
blank.pattern_length = -1.0;
blank
}
fn can_resize_packed_terminal_slab(
slab: &Slab,
inst_tail: u32,
inst_cap: u32,
new_inst_len: u32,
change_count: usize,
) -> bool {
change_count == 1
&& slab.inst_off + slab.inst_len == inst_tail
&& slab.inst_off + new_inst_len <= inst_cap
}
fn alloc_packed_initialized(
device: &wgpu::Device,
cap: u64,
data: &[PackedWireInstance],
) -> wgpu::Buffer {
let buffer = device.create_buffer(&wgpu::BufferDescriptor {
label: Some("wire_arena.packed.ibuf"),
size: cap * std::mem::size_of::<PackedWireInstance>() as u64,
usage: wgpu::BufferUsages::VERTEX | wgpu::BufferUsages::COPY_DST,
mapped_at_creation: true,
});
if !data.is_empty() {
let bytes = bytemuck::cast_slice(data);
let mut mapped = buffer
.slice(..bytes.len() as u64)
.get_mapped_range_mut();
mapped.copy_from_slice(bytes);
drop(mapped);
}
buffer.unmap();
buffer
}
fn visible_ranges(
slabs: &FxHashMap<Handle, Slab>,
view_rot: glam::Mat4,
eye: glam::DVec3,
clip_w: u32,
clip_h: u32,
) -> Vec<(u32, u32)> {
let mut ranges: Vec<(u32, u32)> = slabs
.values()
.filter(|slab| {
slab.inst_len > 0
&& !super::aabb_offscreen(slab.aabb, view_rot, eye, clip_w, clip_h)
})
.map(|slab| (slab.inst_off, slab.inst_off + slab.inst_len))
.collect();
ranges.sort_unstable_by_key(|range| range.0);
let mut merged: Vec<(u32, u32)> = Vec::with_capacity(ranges.len());
for (start, end) in ranges {
if let Some((_, previous_end)) = merged.last_mut() {
if *previous_end == start {
*previous_end = end;
continue;
}
}
merged.push((start, end));
}
// Cap CPU draw-call overhead on pathologically interleaved draw order.
const MAX_RANGES: usize = 64;
if merged.len() > MAX_RANGES {
let group = (merged.len() + MAX_RANGES - 1) / MAX_RANGES;
merged = merged
.chunks(group)
.map(|chunk| (chunk[0].0, chunk[chunk.len() - 1].1))
.collect();
}
merged
}
impl PackedWireArena {
fn build(
device: &wgpu::Device,
wires: &[&WireModel],
depth_map: &FxHashMap<u64, [f32; 2]>,
mesh_edge: bool,
) -> Option<Self> {
let ranges = handle_ranges(wires)?;
let max_instances: usize = wires
.iter()
.map(|wire| wire.points.len().saturating_sub(1))
.sum();
if max_instances as u64 > MAX_PACKED_INSTANCES {
return None;
}
struct PackedSlab {
handle: Handle,
base_depth: f32,
aabb: [f32; 4],
instances: Vec<PackedWireInstance>,
}
use crate::par::prelude::*;
let packed: Vec<PackedSlab> = ranges
.par_iter()
.map(|&(handle, start, end)| {
let run = &wires[start..end];
let base_depth = if mesh_edge {
0.0
} else {
depth_map.get(&handle.value()).map_or(0.0, |depth| depth[0])
};
let mut instances = Vec::with_capacity(
run.iter()
.map(|wire| wire.points.len().saturating_sub(1))
.sum(),
);
for &wire in run {
let draw_depth = if mesh_edge {
0.0
} else {
wire_draw_depth(wire, depth_map)
};
instances.extend(emit_wire_packed(wire, wire.color, draw_depth));
}
PackedSlab {
handle,
base_depth,
aabb: run_aabb(run),
instances,
}
})
.collect();
let inst_count: usize = packed.iter().map(|slab| slab.instances.len()).sum();
if inst_count as u64 > MAX_PACKED_INSTANCES {
return None;
}
let mut instances = Vec::with_capacity(inst_count);
let mut slabs =
FxHashMap::with_capacity_and_hasher(packed.len(), Default::default());
for mut packed_slab in packed {
let inst_off = instances.len() as u32;
let inst_len = packed_slab.instances.len() as u32;
instances.append(&mut packed_slab.instances);
slabs.insert(
packed_slab.handle,
Slab {
inst_off,
inst_len,
const_off: 0,
const_len: 0,
aabb: packed_slab.aabb,
base_depth: packed_slab.base_depth,
},
);
}
let inst_tail = instances.len() as u32;
let inst_cap = ((inst_tail as u64 * HEADROOM_NUM / HEADROOM_DEN)
.max(MIN_INST_CAP)
.min(MAX_PACKED_INSTANCES)) as u32;
let inst_buf = alloc_packed_initialized(device, inst_cap as u64, &instances);
Some(Self {
inst_buf,
inst_cap,
inst_tail,
slabs,
vacant: FxHashMap::default(),
tombstoned: 0,
mesh_edge,
order_sensitive: order_sensitive(wires, depth_map),
})
}
fn write_insts(&self, queue: &wgpu::Queue, off: u32, data: &[PackedWireInstance]) {
if data.is_empty() {
return;
}
let size = std::mem::size_of::<PackedWireInstance>() as u64;
queue.write_buffer(
&self.inst_buf,
off as u64 * size,
bytemuck::cast_slice(data),
);
}
fn patch(
&mut self,
queue: &wgpu::Queue,
changes: &[(Handle, ChangeKind)],
runs: &FxHashMap<Handle, Vec<&WireModel>>,
new_handles_are_suffix: bool,
depth_map: &FxHashMap<u64, [f32; 2]>,
) -> bool {
let mut prepared: FxHashMap<Handle, PreparedPackedPatchRun> =
FxHashMap::default();
for &(handle, kind) in changes {
let run = runs.get(&handle).map(Vec::as_slice).unwrap_or(&[]);
if matches!(kind, ChangeKind::Removed) || run.is_empty() {
continue;
}
let mut insts = Vec::new();
for &wire in run {
let draw_depth = if self.mesh_edge {
0.0
} else {
wire_draw_depth(wire, depth_map)
};
insts.extend(emit_wire_packed(wire, wire.color, draw_depth));
}
let inst_len = insts.len() as u32;
if matches!(kind, ChangeKind::Modified) {
let known = self
.slabs
.get(&handle)
.or_else(|| self.vacant.get(&handle));
let shape_changed =
known.is_some_and(|slab| slab.inst_len != inst_len);
let can_resize_tail = self.slabs.get(&handle).is_some_and(|slab| {
can_resize_packed_terminal_slab(
slab,
self.inst_tail,
self.inst_cap,
inst_len,
changes.len(),
)
});
if shape_changed && !can_resize_tail {
return false;
}
}
prepared.insert(
handle,
PreparedPackedPatchRun {
insts,
base_depth: if self.mesh_edge {
0.0
} else {
depth_map
.get(&handle.value())
.map_or(0.0, |depth| depth[0])
},
aabb: run_aabb(run),
order_sensitive: order_sensitive(run, depth_map),
},
);
}
for &(handle, kind) in changes {
let run = runs.get(&handle).map(Vec::as_slice).unwrap_or(&[]);
if matches!(kind, ChangeKind::Removed) || run.is_empty() {
if let Some(slab) = self.slabs.remove(&handle) {
let blanks =
vec![blank_packed_instance(); slab.inst_len as usize];
self.write_insts(queue, slab.inst_off, &blanks);
self.tombstoned += slab.inst_len;
if matches!(kind, ChangeKind::Modified) {
self.vacant.insert(handle, slab);
}
}
if matches!(kind, ChangeKind::Removed) {
self.vacant.remove(&handle);
}
continue;
}
let PreparedPackedPatchRun {
insts,
base_depth,
aabb,
order_sensitive: run_order_sensitive,
} = prepared
.remove(&handle)
.expect("visible packed wire patch run was prepared");
let inst_len = insts.len() as u32;
if !self.slabs.contains_key(&handle)
&& self
.vacant
.get(&handle)
.is_some_and(|slab| slab.inst_len == inst_len)
{
let slab = self.vacant.remove(&handle).unwrap();
self.tombstoned =
self.tombstoned.saturating_sub(slab.inst_len);
self.slabs.insert(handle, slab);
}
if self
.slabs
.get(&handle)
.is_some_and(|slab| slab.inst_len == inst_len)
{
let inst_off = self.slabs[&handle].inst_off;
self.write_insts(queue, inst_off, &insts);
let slab = self.slabs.get_mut(&handle).unwrap();
slab.base_depth = base_depth;
slab.aabb = aabb;
continue;
}
let can_resize_tail = self.slabs.get(&handle).is_some_and(|slab| {
can_resize_packed_terminal_slab(
slab,
self.inst_tail,
self.inst_cap,
inst_len,
changes.len(),
)
});
if can_resize_tail {
let inst_off = self.slabs[&handle].inst_off;
self.write_insts(queue, inst_off, &insts);
self.inst_tail = inst_off + inst_len;
let slab = self.slabs.get_mut(&handle).unwrap();
slab.inst_len = inst_len;
slab.base_depth = base_depth;
slab.aabb = aabb;
self.order_sensitive |= run_order_sensitive;
continue;
}
let is_new = !self.slabs.contains_key(&handle);
let preserves_submission_order = is_new && new_handles_are_suffix;
if (self.order_sensitive || run_order_sensitive || self.mesh_edge)
&& !preserves_submission_order
{
return false;
}
if self.inst_tail + inst_len > self.inst_cap {
return false;
}
self.vacant.remove(&handle);
if let Some(slab) = self.slabs.remove(&handle) {
let blanks =
vec![blank_packed_instance(); slab.inst_len as usize];
self.write_insts(queue, slab.inst_off, &blanks);
self.tombstoned += slab.inst_len;
}
let inst_off = self.inst_tail;
self.write_insts(queue, inst_off, &insts);
self.inst_tail += inst_len;
self.slabs.insert(
handle,
Slab {
inst_off,
inst_len,
const_off: 0,
const_len: 0,
aabb,
base_depth,
},
);
self.order_sensitive |= run_order_sensitive;
}
self.tombstoned <= self.inst_tail / 2
}
fn wire_gpus(&self) -> Vec<WireGpu> {
if self.inst_tail == 0 {
return Vec::new();
}
vec![WireGpu {
instance_buffer: self.inst_buf.clone(),
first_instance: 0,
instance_count: self.inst_tail,
is_3d_mesh_edge: self.mesh_edge,
const_bind_group: None,
}]
}
fn wire_gpus_visible(
&self,
view_rot: glam::Mat4,
eye: glam::DVec3,
clip_w: u32,
clip_h: u32,
) -> Vec<WireGpu> {
if self.inst_tail == 0 {
return Vec::new();
}
let projected_x = view_rot.transform_vector3(glam::Vec3::X);
let projected_y = view_rot.transform_vector3(glam::Vec3::Y);
let projected_z = view_rot.transform_vector3(glam::Vec3::Z);
let xy_scale = projected_x
.truncate()
.length()
.max(projected_y.truncate().length())
.max(f32::MIN_POSITIVE);
if projected_z.truncate().length() > xy_scale * 1e-5 {
return self.wire_gpus();
}
visible_ranges(&self.slabs, view_rot, eye, clip_w, clip_h)
.into_iter()
.map(|(start, end)| WireGpu {
instance_buffer: self.inst_buf.clone(),
first_instance: start,
instance_count: end - start,
is_3d_mesh_edge: self.mesh_edge,
const_bind_group: None,
})
.collect()
}
}
enum PersistentWireArenaKind {
Indexed(WireArena),
Packed(PackedWireArena),
}
/// Capability-selected arena façade. Callers work with one lifecycle while the
/// adapter preserves the best GPU representation the device supports.
pub struct PersistentWireArena {
inner: PersistentWireArenaKind,
}
impl PersistentWireArena {
pub fn build(
device: &wgpu::Device,
queue: &wgpu::Queue,
wires: &[&WireModel],
depth_map: &FxHashMap<u64, [f32; 2]>,
const_bgl: Option<&wgpu::BindGroupLayout>,
mesh_edge: bool,
) -> Option<Self> {
let inner = if let Some(const_bgl) = const_bgl {
PersistentWireArenaKind::Indexed(WireArena::build(
device, queue, wires, depth_map, const_bgl, mesh_edge,
)?)
} else {
PersistentWireArenaKind::Packed(PackedWireArena::build(
device, wires, depth_map, mesh_edge,
)?)
};
Some(Self { inner })
}
pub fn patch(
&mut self,
queue: &wgpu::Queue,
changes: &[(Handle, ChangeKind)],
runs: &FxHashMap<Handle, Vec<&WireModel>>,
new_handles_are_suffix: bool,
depth_map: &FxHashMap<u64, [f32; 2]>,
) -> bool {
match &mut self.inner {
PersistentWireArenaKind::Indexed(arena) => arena.patch(
queue,
changes,
runs,
new_handles_are_suffix,
depth_map,
),
PersistentWireArenaKind::Packed(arena) => arena.patch(
queue,
changes,
runs,
new_handles_are_suffix,
depth_map,
),
}
}
pub fn wire_gpus(&self) -> Vec<WireGpu> {
match &self.inner {
PersistentWireArenaKind::Indexed(arena) => arena.wire_gpus(),
PersistentWireArenaKind::Packed(arena) => arena.wire_gpus(),
}
}
pub fn wire_gpus_visible(
&self,
view_rot: glam::Mat4,
eye: glam::DVec3,
clip_w: u32,
clip_h: u32,
) -> Vec<WireGpu> {
match &self.inner {
PersistentWireArenaKind::Indexed(arena) => {
arena.wire_gpus_visible(view_rot, eye, clip_w, clip_h)
}
PersistentWireArenaKind::Packed(arena) => {
arena.wire_gpus_visible(view_rot, eye, clip_w, clip_h)
}
}
}
}
#[cfg(test)]
mod tests {
use super::*;
fn slab() -> Slab {
Slab {
inst_off: 100,
inst_len: 10,
const_off: 20,
const_len: 2,
aabb: [0.0; 4],
base_depth: 0.0,
}
}
#[test]
fn terminal_slab_can_grow_without_relocating_the_arena() {
assert!(can_resize_terminal_slab(
&slab(),
110,
22,
1000,
100,
18,
3,
1,
));
}
#[test]
fn non_terminal_or_batched_resize_uses_clean_fallback() {
assert!(!can_resize_terminal_slab(
&slab(),
111,
22,
1000,
100,
18,
3,
1,
));
assert!(!can_resize_terminal_slab(
&slab(),
110,
22,
1000,
100,
18,
3,
2,
));
}
#[test]
fn packed_terminal_resize_obeys_order_and_capacity() {
assert!(can_resize_packed_terminal_slab(
&slab(),
110,
1000,
18,
1,
));
assert!(!can_resize_packed_terminal_slab(
&slab(),
111,
1000,
18,
1,
));
assert!(!can_resize_packed_terminal_slab(
&slab(),
110,
117,
18,
1,
));
assert!(!can_resize_packed_terminal_slab(
&slab(),
110,
1000,
18,
2,
));
}
#[test]
fn tombstones_use_the_shader_discard_sentinel() {
assert!(blank_const().pattern_length < 0.0);
assert!(blank_packed_instance().pattern_length < 0.0);
}
}