Extract draw merge final plane composite helper

src/canvas.cpp

@@ -508,6 +508,36 @@ static void execute_canvas_draw_merge_final_plane_composite(
     pp::panopainter::execute_legacy_canvas_draw_merge_final_plane_composite(uniforms, execution);
 }
 
+static pp::panopainter::LegacyCanvasDrawMergeFinalPlaneCompositeExecution
+make_canvas_draw_merge_final_plane_composite_execution(Canvas& canvas)
+{
+    return {
+        .bind_merged_texture_copy_target = [&] {
+            canvas.set_active_texture_unit(2);
+            canvas.m_merge_tex.bind();
+        },
+        .copy_merged_framebuffer = [&] {
+            canvas.copy_framebuffer_to_texture_2d(0, 0, 0, 0, canvas.m_width, canvas.m_height);
+        },
+        .enable_blend = [&] {
+            canvas.apply_canvas_capability(canvas.blend_state(), true);
+        },
+        .draw = [&] {
+            canvas.m_plane.draw_fill();
+        },
+        .bind_sampler = [&] {
+            canvas.m_sampler.bind(0);
+        },
+        .bind_merged_texture = [&] {
+            canvas.set_active_texture_unit(0);
+            canvas.m_merge_tex.bind();
+        },
+        .unbind_merged_texture = [&] {
+            canvas.m_merge_tex.unbind();
+        },
+    };
+}
+
 static void execute_canvas_draw_merge_plane_final_composite(
     Canvas& canvas,
     const glm::mat4& ortho,
@@ -1450,31 +1480,7 @@ void Canvas::draw_merge_final_plane_composite(
             },
             .draw_checkerboard = draw_checkerboard,
         },
-        pp::panopainter::LegacyCanvasDrawMergeFinalPlaneCompositeExecution {
+        make_canvas_draw_merge_final_plane_composite_execution(*this));
-            .bind_merged_texture_copy_target = [&] {
-                set_active_texture_unit(2);
-                m_merge_tex.bind();
-            },
-            .copy_merged_framebuffer = [&] {
-                copy_framebuffer_to_texture_2d(0, 0, 0, 0, m_width, m_height);
-            },
-            .enable_blend = [&] {
-                apply_canvas_capability(blend_state(), true);
-            },
-            .draw = [&] {
-                m_plane.draw_fill();
-            },
-            .bind_sampler = [&] {
-                m_sampler.bind(0);
-            },
-            .bind_merged_texture = [&] {
-                set_active_texture_unit(0);
-                m_merge_tex.bind();
-            },
-            .unbind_merged_texture = [&] {
-                m_merge_tex.unbind();
-            },
-        });
 }
 
 void Canvas::stroke_draw_dual_pass(