Q-W2: split bank_panel.cpp (3459 LOC) into eight shell/panel TUs — reasampler::panel internals, per-seam public headers, shim retired; zero behavior change, 60/60 green

2026-07-29 10:55:58 -04:00
parent b5788c82f6
commit 30a4ffd01b
20 changed files with 4084 additions and 3596 deletions
@@ -0,0 +1,117 @@
+// panel_audition.cpp — the audition/preview engine seam of the docked bank panel
+// (Q-W2 split of bank_panel.cpp; M5 Wave B). HOT PATH GUARDRAIL (T4-28 / Q-W2): the
+// preview path stays a DIRECT free-function call-through — no interface, no virtual
+// dispatch, no added header->TU indirection; the idle path is unchanged in shape.
+//
+// Compiled into the reaper_reasampler MODULE. Includes reaper_plugin_functions.h
+// WITHOUT REAPERAPI_IMPLEMENT — main.cpp owns the API pointers; here they are
+// extern (CLAUDE.md §contract). DAW-verified, not unit tested.
+
+#include <string>
+
+#include "shell/panel/panel_state.h"
+
+// Stock preview API (verified against reaper_plugin.h / reaper_plugin_functions.h):
+// PlayPreview/StopPreview drive a caller-owned preview_register_t. These are the
+// STOCK symbols (not SWS-only) — see the audition section below.
+#define REAPERAPI_MINIMAL
+#define REAPERAPI_WANT_PlayPreview
+#define REAPERAPI_WANT_StopPreview
+#define REAPERAPI_WANT_PCM_Source_CreateFromFile
+#define REAPERAPI_WANT_PCM_Source_Destroy
+#include "reaper_plugin_functions.h"
+
+namespace reasampler::panel {
+
+// --- Audition preview ---------------------------------------------------------
+//
+// READ-ONLY / NON-DESTRUCTIVE (load-bearing principle): audition is PREVIEW
+// playback only. It NEVER inserts into the arrange, creates items/tracks, or
+// mutates the project or bank. PlayPreview streams a caller-owned PCM_source
+// through REAPER's preview bus and touches nothing in the project.
+//
+// FLAGGED RUNTIME ASSUMPTIONS (header does not specify these; verified only by
+// signature/struct, not semantics — DAW-verify):
+//   1. REAPER's audio thread reads the preview_register_t by POINTER while the
+//      preview is active (the struct's own comment mandates a cs/mutex we init),
+//      so the register must outlive playback — we hold it in g_panel (static),
+//      never on the stack.
+//   2. StopPreview is assumed to detach the source from the audio thread BEFORE it
+//      returns, making it safe to PCM_Source_Destroy the source immediately after.
+//      This is the conventional contract (SWS' preview helpers rely on it) but is
+//      NOT documented in the header — flagged. If a rare race surfaced, the fix is
+//      a StartPreviewFade + deferred free; not done now (YAGNI, no evidence).
+//   3. m_out_chan == 0 routes to the first hardware output pair (stereo). We do not
+//      set mono (&1024). volume 1.0, loop false, curpos 0.
+
+void initPreview() {
+    if (g_panel.previewInited) return;
+#ifdef _WIN32
+    InitializeCriticalSection(&g_panel.preview.cs);
+#else
+    pthread_mutex_init(&g_panel.preview.mutex, nullptr);
+#endif
+    g_panel.previewInited = true;
+}
+
+void stopAudition() {
+    if (g_panel.previewActive) {
+        StopPreview(&g_panel.preview);
+        g_panel.previewActive = false;
+    }
+    if (g_panel.previewSrc) {
+        PCM_Source_Destroy(g_panel.previewSrc);
+        g_panel.previewSrc = nullptr;
+    }
+    g_panel.preview.src = nullptr;
+}
+
+void deinitPreview() {
+    if (!g_panel.previewInited) return;
+#ifdef _WIN32
+    DeleteCriticalSection(&g_panel.preview.cs);
+#else
+    pthread_mutex_destroy(&g_panel.preview.mutex);
+#endif
+    g_panel.previewInited = false;
+}
+
+// Auditions the sample at selection ordinal `idx` of the FOCUSED region's displayed bank.
+// L7: `idx` is a DISPLAY-order (slot) ordinal, resolved through orderedIds, not a raw
+// BankModel position.
+void startAudition(int idx) {
+    stopAudition();
+
+    const BankModel* index = indexForRegion(g_panel.focusedRegion);
+    if (!index) return;
+    const RegionDisplay disp = focusedDisplay();
+    if (idx < 0 || idx >= disp.occupiedCount()) return;
+    const Sample* s = index->query(disp.orderedIds[static_cast<std::size_t>(idx)]);
+    if (!s) return;
+
+    const std::string projectDir = currentProjectDir();
+    const std::string abs = resolveBankFile(projectDir, s->relativePath);
+    if (abs.empty()) return;
+
+    PCM_source* src = PCM_Source_CreateFromFile(abs.c_str());
+    if (!src) return;
+
+    g_panel.preview.src = src;
+    g_panel.preview.m_out_chan = 0;
+    g_panel.preview.curpos = 0.0;
+    g_panel.preview.loop = false;
+    g_panel.preview.volume = 1.0;
+    g_panel.preview.peakvol[0] = 0.0;
+    g_panel.preview.peakvol[1] = 0.0;
+    g_panel.preview.preview_track = nullptr;
+
+    if (PlayPreview(&g_panel.preview) != 0) {
+        g_panel.previewSrc = src;
+        g_panel.previewActive = true;
+    } else {
+        PCM_Source_Destroy(src);
+        g_panel.preview.src = nullptr;
+    }
+}
+
+}  // namespace reasampler::panel