create external framebuffer grabber

cleanup some cmakelist files
fix qt5 build


Former-commit-id: 024b5b6dc5dc96fcb16f6e8958ad3684a6728504

include/grabber/FramebufferFrameGrabber.h

@@ -0,0 +1,59 @@
+#pragma once
+
+// Utils includes
+#include <utils/Image.h>
+#include <utils/ColorRgb.h>
+#include <utils/VideoMode.h>
+#include <utils/ImageResampler.h>
+
+///
+/// The FramebufferFrameGrabber is used for creating snapshots of the display (screenshots) 
+///
+class FramebufferFrameGrabber
+{
+public:
+	///
+	/// Construct a FramebufferFrameGrabber that will capture snapshots with specified dimensions.
+	///
+	/// @param[in] device The framebuffer device name/path
+	/// @param[in] width  The width of the captured screenshot
+	/// @param[in] height The heigth of the captured screenshot
+	///
+	FramebufferFrameGrabber(const std::string & device, const unsigned width, const unsigned height);
+	~FramebufferFrameGrabber();
+
+	///
+	/// Set the video mode (2D/3D)
+	/// @param[in] mode The new video mode
+	///
+	void setVideoMode(const VideoMode videoMode);
+
+	///
+	/// Captures a single snapshot of the display and writes the data to the given image. The
+	/// provided image should have the same dimensions as the configured values (_width and
+	/// _height)
+	///
+	/// @param[out] image  The snapped screenshot (should be initialized with correct width and
+	/// height)
+	///
+	void grabFrame(Image<ColorRgb> & image);
+
+private:
+	/// Framebuffer file descriptor
+	int _fbfd;
+
+	/// Pointer to framebuffer
+	unsigned char * _fbp;
+	
+	/// Framebuffer device e.g. /dev/fb0
+	const std::string _fbDevice;
+	
+	/// With of the captured snapshot [pixels]
+	const unsigned _width;
+	
+	/// Height of the captured snapshot [pixels]
+	const unsigned _height;
+
+	/// Image resampler for downscaling the image
+	ImageResampler * _imgResampler;
+};