Add Renderer::getAspectRatio() method

src/celengine/render.cpp

@@ -8076,3 +8076,8 @@ void Renderer::setRenderRegion(int x, int y, int width, int height, bool withSci
     setViewport(x, y, width, height);
     resize(width, height);
 }
+
+float Renderer::getAspectRatio() const
+{
+    return static_cast<float>(windowWidth) / static_cast<float>(windowHeight);
+}

src/celengine/render.h

@@ -114,6 +114,7 @@ class Renderer
 #endif
     void shutdown() {};
     void resize(int, int);
+    float getAspectRatio() const;
 
     float calcPixelSize(float fovY, float windowHeight);
     void setFaintestAM45deg(float);