[core] Refactor HeadlessBackend

1 files changed, 16 insertions, 43 deletions

diff --git a/include/mbgl/platform/default/headless_backend.hpp b/include/mbgl/platform/default/headless_backend.hpp
index b6c654943f..2fef321d85 100644
--- a/include/mbgl/platform/default/headless_backend.hpp
+++ b/include/mbgl/platform/default/headless_backend.hpp
@@ -1,23 +1,9 @@
 #pragma once
 
 #include <mbgl/gl/implementation.hpp>
-
-#if MBGL_USE_QT
-class QGLWidget;
-#elif MBGL_USE_CGL
-#include <OpenGL/OpenGL.h>
-#elif MBGL_USE_GLX
-typedef struct _XDisplay Display;
-typedef struct __GLXcontextRec* GLXContext;
-typedef struct __GLXFBConfigRec* GLXFBConfig;
-typedef long unsigned int XID;
-typedef XID GLXPbuffer;
-#elif MBGL_USE_OSMESA
-#include <GL/osmesa.h>
-#endif
+#include <mbgl/gl/extension.hpp>
 
 #include <mbgl/map/backend.hpp>
-#include <mbgl/gl/extension.hpp>
 
 #include <memory>
 #include <functional>
@@ -39,47 +25,34 @@ public:
 
     void setMapChangeCallback(std::function<void(MapChange)>&& cb) { mapChangeCallback = std::move(cb); }
 
-private:
-    void activateContext();
-    void deactivateContext();
+    struct Impl {
+        virtual ~Impl() {}
+        virtual void activateContext() = 0;
+        virtual void deactivateContext() {}
+    };
 
 private:
     // Implementation specific functions
     static gl::glProc initializeExtension(const char*);
+
+    bool hasContext() const { return bool(impl); }
+    bool hasDisplay();
+
     void createContext();
+
+private:
     void destroyContext();
 
+    void activateContext();
+    void deactivateContext();
+
+    std::unique_ptr<Impl> impl;
     std::shared_ptr<HeadlessDisplay> display;
 
     bool extensionsLoaded = false;
     bool active = false;
 
-#if MBGL_USE_QT
-    QGLWidget* glContext = nullptr;
-#endif
-
-#if MBGL_USE_CGL
-    CGLContextObj glContext = nullptr;
-#endif
-
-#if MBGL_USE_EAGL
-    void *glContext = nullptr;
-#endif
-
-#if MBGL_USE_GLX
-    Display *xDisplay = nullptr;
-    GLXFBConfig *fbConfigs = nullptr;
-    GLXContext glContext = nullptr;
-    GLXPbuffer glxPbuffer = 0;
-#endif
-
-#if MBGL_USE_OSMESA
-    OSMesaContext glContext = nullptr;
-    GLubyte fakeBuffer = 0;
-#endif
-
     std::function<void(MapChange)> mapChangeCallback;
-
 };
 
 } // namespace mbgl