Changed RgbImage to template based Image (with template for pixel type)

Former-commit-id: ef02f164eaf3c2f9dd552c1c17b525cf6eed499c

include/utils/Image.h

@@ -0,0 +1,177 @@
+#pragma once
+
+// STL includes
+#include <vector>
+#include <cstdint>
+#include <cstring>
+#include <algorithm>
+
+template <typename Pixel_T>
+class Image
+{
+public:
+
+	typedef Pixel_T pixel_type;
+
+	///
+	/// Constructor for an image with specified width and height
+	///
+	/// @param width The width of the image
+	/// @param height The height of the image
+	///
+	Image(const unsigned width, const unsigned height) :
+		_width(width),
+		_height(height),
+		_pixels(new Pixel_T[width*height + 1]),
+		_endOfPixels(_pixels + width*height)
+	{
+		memset(_pixels, 0, (_width*_height+1)*sizeof(Pixel_T));
+	}
+
+	///
+	/// Constructor for an image with specified width and height
+	///
+	/// @param width The width of the image
+	/// @param height The height of the image
+	/// @param background The color of the image
+	///
+	Image(const unsigned width, const unsigned height, const Pixel_T background) :
+		_width(width),
+		_height(height),
+		_pixels(new Pixel_T[width*height + 1]),
+		_endOfPixels(_pixels + width*height)
+	{
+		std::fill(_pixels, _endOfPixels, background);
+	}
+
+	///
+	/// Destructor
+	///
+	~Image()
+	{
+		delete[] _pixels;
+	}
+
+	///
+	/// Returns the width of the image
+	///
+	/// @return The width of the image
+	///
+	inline unsigned width() const
+	{
+		return _width;
+	}
+
+	///
+	/// Returns the height of the image
+	///
+	/// @return The height of the image
+	///
+	inline unsigned height() const
+	{
+		return _height;
+	}
+
+	uint8_t alpha(const unsigned pixel) const
+	{
+		return (_pixels + pixel)->red;
+	}
+
+	uint8_t red(const unsigned pixel) const
+	{
+		return (_pixels + pixel)->red;
+	}
+
+	uint8_t green(const unsigned pixel) const
+	{
+		return (_pixels + pixel)->green;
+	}
+
+	uint8_t blue(const unsigned pixel) const
+	{
+		return (_pixels + pixel)->blue;
+	}
+
+	///
+	/// Returns a const reference to a specified pixel in the image
+	///
+	/// @param x The x index
+	/// @param y The y index
+	///
+	/// @return const reference to specified pixel
+	///
+	const Pixel_T& operator()(const unsigned x, const unsigned y) const
+	{
+		return _pixels[toIndex(x,y)];
+	}
+
+	///
+	/// Returns a reference to a specified pixel in the image
+	///
+	/// @param x The x index
+	/// @param y The y index
+	///
+	/// @return reference to specified pixel
+	///
+	Pixel_T& operator()(const unsigned x, const unsigned y)
+	{
+		return _pixels[toIndex(x,y)];
+	}
+
+	///
+	/// Copies another image into this image. The images should have exactly the same size.
+	///
+	/// @param other The image to copy into this
+	///
+	void copy(const Image<Pixel_T>& other)
+	{
+		assert(other._width == _width);
+		assert(other._height == _height);
+
+		memcpy(_pixels, other._pixels, _width*_height*sizeof(Pixel_T));
+	}
+
+	///
+	/// Returns a memory pointer to the first pixel in the image
+	/// @return The memory pointer to the first pixel
+	///
+	Pixel_T* memptr()
+	{
+		return _pixels;
+	}
+
+	///
+	/// Returns a const memory pointer to the first pixel in the image
+	/// @return The const memory pointer to the first pixel
+	///
+	const Pixel_T* memptr() const
+	{
+		return _pixels;
+	}
+private:
+
+	///
+	/// Translate x and y coordinate to index of the underlying vector
+	///
+	/// @param x The x index
+	/// @param y The y index
+	///
+	/// @return The index into the underlying data-vector
+	///
+	inline unsigned toIndex(const unsigned x, const unsigned y) const
+	{
+		return y*_width + x;
+	}
+
+private:
+	/// The width of the image
+	const unsigned _width;
+	/// The height of the image
+	const unsigned _height;
+
+	/// The pixels of the image
+	Pixel_T* _pixels;
+
+	/// Pointer to the last(extra) pixel
+	Pixel_T* _endOfPixels;
+};