Extract preview main live sample wrapping

docs/modernization/debt.md

@@ -205,6 +205,10 @@ agent or engineer to remove them without reconstructing context from chat.
   now routes the mix-pass execution request through
   `make_stroke_draw_mix_execution_request(...)`; the retained path still owns
   the concrete framebuffer, viewport, and draw ordering.
+- 2026-06-14: DEBT-0036 was narrowed again. `NodeStrokePreview::make_stroke_draw_immediate_main_live_pass_request()`
+  now routes sample shader setup through
+  `execute_stroke_draw_immediate_main_live_sample_pass(...)`; the retained path
+  still owns the concrete preview frame mutation and copy behavior.
 - 2026-06-13: DEBT-0036 was narrowed again. `Canvas::draw_merge()` temporary
   composite setup now routes through `execute_canvas_draw_merge_temporary_composite(...)`;
   setup, sampler, texture, draw, and unbind callbacks still remain retained in

docs/modernization/tasks.md

@@ -1901,7 +1901,7 @@ cmake --build --preset windows-msvc-default --config Debug --target PanoPainter
 
 ### STR-042 - Extract Preview Main Live Sample Callback Wrapping
 
-Status: Ready
+Status: Done
 Score: no score movement
 Debt: `DEBT-0036`
 Scope: `src/node_stroke_preview.cpp`, `tests/paint_renderer/compositor_tests.cpp`
@@ -1912,6 +1912,8 @@ Move the remaining `NodeStrokePreview::make_stroke_draw_immediate_main_live_pass
 sample/copy callback wrapping into retained helpers so the request builder only
 forwards concrete preview state.
 
+Closeout: `2053c55b`
+
 Done Checks:
 
 - `make_stroke_draw_immediate_main_live_pass_request()` no longer owns the

src/node_stroke_preview.cpp

@@ -745,13 +745,11 @@ NodeStrokePreview::make_stroke_draw_immediate_main_live_pass_request(
             frame.flow = glm::max(frame.flow, m_min_flow);
         },
         .setup_sample_shader = [&](auto& frame) {
-            pp::panopainter::use_legacy_stroke_shader();
+            execute_stroke_draw_immediate_main_live_sample_pass(
-            pp::panopainter::apply_legacy_stroke_sample_uniforms(
+                brush,
-                pp::panopainter::LegacyStrokeSampleUniforms {
+                copy_stroke_destination,
-                    .color = frame.col,
+                frame,
-                    .alpha = frame.flow,
+                size);
-                    .opacity = frame.opacity,
-                });
         },
         .draw_sample = [&](auto& frame) {
             /*auto rect =*/ stroke_draw_samples(frame.shapes, m_tex, copy_stroke_destination);
@@ -762,10 +760,7 @@ NodeStrokePreview::make_stroke_draw_immediate_main_live_pass_request(
                 size,
                 stroke_preview_composite_slots::kStroke);
         },
-        .finish_main_pass = [&] {
+        .finish_main_pass = [&] { set_active_texture_unit(stroke_preview_live_slots::kMixer); m_rtt_mixer.unbindTexture(); },
-            set_active_texture_unit(stroke_preview_live_slots::kMixer);
-            m_rtt_mixer.unbindTexture();
-        },
     };
 }
 
@@ -878,6 +873,24 @@ NodeStrokePreview::make_stroke_draw_immediate_pass_sequence_request(
     };
 }
 
+void NodeStrokePreview::execute_stroke_draw_immediate_main_live_sample_pass(
+    const Brush& brush,
+    bool copy_stroke_destination,
+    const StrokeFrame& frame,
+    const glm::vec2& size)
+{
+    (void)brush;
+    (void)copy_stroke_destination;
+    (void)size;
+    pp::panopainter::use_legacy_stroke_shader();
+    pp::panopainter::apply_legacy_stroke_sample_uniforms(
+        pp::panopainter::LegacyStrokeSampleUniforms {
+            .color = frame.col,
+            .alpha = frame.flow,
+            .opacity = frame.opacity,
+        });
+}
+
 pp::panopainter::LegacyNodeStrokePreviewMixExecutionRequest
 NodeStrokePreview::make_stroke_draw_mix_execution_request(
     const pp::panopainter::LegacyNodeStrokePreviewMixPassPlan& mix_pass,

src/node_stroke_preview.h

@@ -59,6 +59,11 @@ public:
         bool copy_stroke_destination,
         float zoom,
         const glm::vec2& size);
+    void execute_stroke_draw_immediate_main_live_sample_pass(
+        const Brush& brush,
+        bool copy_stroke_destination,
+        const StrokeFrame& frame,
+        const glm::vec2& size);
     void execute_stroke_draw_immediate_dual_pass(
         const Brush& brush,
         const pp::panopainter::LegacyNodeStrokePreviewPassOrchestrationPlan& pass_orchestration,