staging some future refactoring, .h -> hpp, fix for rendering w/ audio

src/imgui/window/spritesheet_editor.hpp

@@ -0,0 +1,26 @@
+#pragma once
+
+#include "canvas.h"
+#include "manager.h"
+#include "resources.h"
+#include "settings.h"
+
+namespace anm2ed::imgui
+{
+  class SpritesheetEditor : public Canvas
+  {
+    glm::vec2 mousePos{};
+    glm::vec2 previousMousePos{};
+    glm::vec2 cropAnchor{};
+    glm::vec2 checkerPan{};
+    glm::vec2 checkerSyncPan{};
+    float checkerSyncZoom{};
+    bool isCheckerPanInitialized{};
+    bool hasPendingZoomPanAdjust{};
+    int hoveredRegionId{-1};
+
+  public:
+    SpritesheetEditor();
+    void update(Manager&, Settings&, Resources&);
+  };
+}