Explicit dynamics core: central differences, one-point hex8 with hourglass control, nodal-pressure tet4, solve.explicit (M10 X1) (#27)

* Model: explicit dynamic steps (end time, increment scale and cap, output intervals, initial velocities, rigid walls, hourglass and bulk viscosity controls); deck writers refuse them Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm * fem: uniform-strain hex8 and tet4 kinematics, Flanagan–Belytschko hourglass shape vectors, element frequency bound Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm * Explicit solver crate (L2): central differences with lumped mass, one-point hex8 with Flanagan–Belytschko hourglass control, Bonet–Burton tet4, bulk viscosity, rigid walls, energy account; wave and impact verification Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm * Engine: solve.explicit and solve.history commands, explicit results in the session and solve.probe; cantilever period against the modal solver Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm * Docs: explicit solver in the architecture, roadmap (M10 started), parity and literature (Part H) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm * Simplify: Model::select_step shared by both solvers, Procedure::sets/is_dynamic, fused per-increment passes without allocation, shared element tail, generic command caps Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm * Catalogue: solve.explicit is ready; solve.history beside solve.probe Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm * Rebase onto the implicit couplings work: Procedure is no longer Copy Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm --------- Co-authored-by: jyviko <2501648+jyviko@users.noreply.github.com> Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-13 18:28:32 -04:00
1 parent 48039639cb
commit d45a2da5b5
@@ -21,10 +21,10 @@ pub mod sample;
 use std::collections::BTreeMap;
 use std::sync::Arc;

+use modelcraft_explicit::ExplicitResult;
 use modelcraft_geometry::Design;
 use modelcraft_geometry::tagged_mesh::TaggedSurface;
 use modelcraft_model::Model;
-use modelcraft_solver::StepResult;
 use serde_json::Value;

 use crate::history::History;
@@ -47,6 +47,8 @@ pub enum EngineError {
    Deck(#[from] modelcraft_decks::Error),
    #[error(transparent)]
    Solver(#[from] modelcraft_solver::Error),
+    #[error(transparent)]
+    Explicit(#[from] modelcraft_explicit::Error),
    /// A command panicked; the model is unchanged.
    #[error("internal error in {command}: {message}")]
    Internal { command: String, message: String },
@@ -54,6 +56,30 @@ pub enum EngineError {

 pub type Result<T> = std::result::Result<T, EngineError>;

+/// The result of a solved step, from the implicit or the explicit solver.
+#[derive(Debug, Clone, PartialEq)]
+pub enum StepResult {
+    Implicit(modelcraft_solver::StepResult),
+    Explicit(ExplicitResult),
+}
+
+impl StepResult {
+    pub fn step(&self) -> &str {
+        match self {
+            StepResult::Implicit(r) => r.step(),
+            StepResult::Explicit(r) => &r.step,
+        }
+    }
+
+    /// The node labels the result's per-node values follow, sorted.
+    pub fn nodes(&self) -> &[u32] {
+        match self {
+            StepResult::Implicit(r) => r.nodes(),
+            StepResult::Explicit(r) => &r.nodes,
+        }
+    }
+}
+
 /// What a command works on, which decides how [`Session::execute`] records it.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum CommandKind {