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

src/imgui/window/animation_preview.hpp

@@ -0,0 +1,39 @@
+#pragma once
+
+#include <filesystem>
+
+#include "audio_stream.h"
+#include "canvas.h"
+#include "manager.h"
+#include "resources.h"
+#include "settings.h"
+
+namespace anm2ed::imgui
+{
+  class AnimationPreview : public Canvas
+  {
+    MIX_Mixer* mixer = MIX_CreateMixerDevice(SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK, nullptr);
+    AudioStream audioStream = AudioStream(mixer);
+    bool isPreviewHovered{};
+    bool isSizeTrySet{true};
+    Settings savedSettings{};
+    float savedZoom{};
+    glm::vec2 savedPan{};
+    int savedOverlayIndex{};
+    glm::vec2 mousePos{};
+    glm::vec2 checkerPan{};
+    glm::vec2 checkerSyncPan{};
+    float checkerSyncZoom{};
+    bool isCheckerPanInitialized{};
+    bool hasPendingZoomPanAdjust{};
+    bool isMoveDragging{};
+    glm::vec2 moveOffset{};
+    std::filesystem::path renderTempDirectory{};
+    std::vector<std::filesystem::path> renderTempFrames{};
+
+  public:
+    AnimationPreview();
+    void tick(Manager&, Settings&);
+    void update(Manager&, Settings&, Resources&);
+  };
+}