// VncSharp - .NET VNC Client Library

// Copyright (C) 2008 David Humphrey

//

// This program is free software; you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation; either version 2 of the License, or

// (at your option) any later version.

//

// This program is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with this program; if not, write to the Free Software

// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

using System;

using System.Drawing;

// ReSharper disable ArrangeAccessorOwnerBody

namespace VncSharpCore

{

/// <summary>

/// Properties of a VNC Framebuffer, and its Pixel Format.

/// </summary>

public class Framebuffer

{

private string name;

private readonly int[] pixels; // I'm reusing the same pixel buffer for all update rectangles.

// Pixel values will always be 32-bits to match GDI representation

/// <summary>

/// Creates a new Framebuffer with (width x height) pixels.

/// </summary>

/// <param name="width">The width in pixels of the remote desktop.</param>

/// <param name="height">The height in pixels of the remote desktop.</param>

private Framebuffer(int width, int height)

{

Width = width;

Height = height;

// Cache the total size of the pixel array and initialize

// The total number of pixels (w x h) assigned in SetSize()

var pixelCount = width * height;

pixels = new int[pixelCount];

}

/// <summary>

/// An indexer to allow access to the internal pixel buffer.

/// </summary>

public int this[int index] {

get {

return pixels[index];

}

set {

pixels[index] = value;

}

}

/// <summary>

/// The Width of the Framebuffer, measured in Pixels.

/// </summary>

public int Width { get; }

/// <summary>

/// The Height of the Framebuffer, measured in Pixels.

/// </summary>

public int Height { get; }

/// <summary>

/// Gets a Rectangle object constructed out of the Width and Height for the Framebuffer. Used as a convenience in other classes.

/// </summary>

public Rectangle Rectangle

{

get { return new Rectangle(0, 0, Width, Height); }

}

/// <summary>

/// The number of Bits Per Pixel for the Framebuffer--one of 8, 16, or 32.

/// </summary>

public int BitsPerPixel { get; private set; }

/// <summary>

/// The Colour Depth of the Framebuffer.

/// </summary>

private int Depth { get; set; }

/// <summary>

/// Indicates whether the remote host uses Big- or Little-Endian order when sending multi-byte values.

/// </summary>

private bool BigEndian { get; set; }

/// <summary>

/// Indicates whether the remote host supports True Colour.

/// </summary>

private bool TrueColour { get; set; }

/// <summary>

/// The maximum value for Red in a pixel's colour value.

/// </summary>

public int RedMax { get; private set; }

/// <summary>

/// The maximum value for Green in a pixel's colour value.

/// </summary>

public int GreenMax { get; private set; }

/// <summary>

/// The maximum value for Blue in a pixel's colour value.

/// </summary>

public int BlueMax { get; private set; }

/// <summary>

/// The number of bits to shift pixel values in order to obtain Red values.

/// </summary>

public int RedShift { get; private set; }

/// <summary>

/// The number of bits to shift pixel values in order to obtain Green values.

/// </summary>

public int GreenShift { get; private set; }

/// <summary>

/// The number of bits to shift pixel values in order to obtain Blue values.

/// </summary>

public int BlueShift { get; private set; }

/// <summary>

/// The name of the remote destkop, if any. Must be non-null.

/// </summary>

/// <exception cref="ArgumentNullException">Thrown if a null string is used when setting DesktopName.</exception>

public string DesktopName {

get {

return name;

}

set {

if (value == null)

throw new ArgumentNullException($"DesktopName");

name = value;

}

}

/// <summary>

/// When communicating with the VNC Server, bytes are used to represent many of the values above. However, internally it is easier to use Integers. This method provides a translation between the two worlds.

/// </summary>

/// <returns>A byte array of 16 bytes containing the properties of the framebuffer in a format ready for transmission to the VNC server.</returns>

public byte[] ToPixelFormat()

{

var b = new byte[16];

b[0] = (byte) BitsPerPixel;

b[1] = (byte) Depth;

b[2] = (byte) (BigEndian ? 1 : 0);

b[3] = (byte) (TrueColour ? 1 : 0);

b[4] = (byte) ((RedMax >> 8) & 0xff);

b[5] = (byte) (RedMax & 0xff);

b[6] = (byte) ((GreenMax >> 8) & 0xff);

b[7] = (byte) (GreenMax & 0xff);

b[8] = (byte) ((BlueMax >> 8) & 0xff);

b[9] = (byte) (BlueMax & 0xff);

b[10] = (byte) RedShift;

b[11] = (byte) GreenShift;

b[12] = (byte) BlueShift;

// plus 3 bytes padding = 16 bytes

return b;

}

/// <summary>

/// Given the dimensions and 16-byte PIXEL_FORMAT record from the VNC Host, deserialize this into a Framebuffer object.

/// </summary>

/// <param name="b">The 16-byte PIXEL_FORMAT record.</param>

/// <param name="width">The width in pixels of the remote desktop.</param>

/// <param name="height">The height in pixles of the remote desktop.</param>

/// <param name="bitsPerPixel">The number of Bits Per Pixel for the Framebuffer--one of 8, 16, or 32.</param>

/// <param name="depth">The Colour Depth of the Framebuffer--one of 3, 6, 8 or 16.</param>

/// <returns>Returns a Framebuffer object matching the specification of b[].</returns>

public static Framebuffer FromPixelFormat(byte[] b, int width, int height, int bitsPerPixel, int depth)

{

if (b.Length != 16)

throw new ArgumentException("Length of b must be 16 bytes.");

var buffer = new Framebuffer(width, height);

if ((bitsPerPixel == 16) && (depth == 16))

{

buffer.BitsPerPixel = 16;

buffer.Depth = 16;

buffer.BigEndian = b[2] != 0;

buffer.TrueColour = false;

buffer.RedMax = 31;

buffer.GreenMax = 63;

buffer.BlueMax = 31;

buffer.RedShift = 11;

buffer.GreenShift = 5;

buffer.BlueShift = 0;

}

else if ((bitsPerPixel) == 16 && (depth == 8))

{

buffer.BitsPerPixel = 16;

buffer.Depth = 8;

buffer.BigEndian = b[2] != 0;

buffer.TrueColour = false;

buffer.RedMax = 31;

buffer.GreenMax = 63;

buffer.BlueMax = 31;

buffer.RedShift = 11;

buffer.GreenShift = 5;

buffer.BlueShift = 0;

}

else if ((bitsPerPixel) == 8 && (depth == 8))

{

buffer.BitsPerPixel = 8;

buffer.BigEndian = b[2] != 0;

buffer.TrueColour = false;

buffer.Depth = 8;

buffer.RedMax = 7;

buffer.GreenMax = 7;

buffer.BlueMax = 3;

buffer.RedShift = 0;

buffer.GreenShift = 3;

buffer.BlueShift = 6;

}

else if ((bitsPerPixel) == 8 && (depth == 6))

{

buffer.BitsPerPixel = 8;

buffer.Depth = 6;

buffer.BigEndian = b[2] != 0;

buffer.TrueColour = false;

buffer.RedMax = 3;

buffer.GreenMax = 3;

buffer.BlueMax = 3;

buffer.RedShift = 4;

buffer.GreenShift = 2;

buffer.BlueShift = 0;

}

else if ((bitsPerPixel == 8) && (depth == 3))

{

buffer.BitsPerPixel = 8;

buffer.Depth = 3;

buffer.BigEndian = b[2] != 0;

buffer.TrueColour = false;

buffer.RedMax = 1;

buffer.GreenMax = 1;

buffer.BlueMax = 1;

buffer.RedShift = 2;

buffer.GreenShift = 1;

buffer.BlueShift = 0;

}

else

{

buffer.BitsPerPixel = b[0];

buffer.Depth = b[1];

buffer.BigEndian = b[2] != 0;

buffer.TrueColour = b[3] != 0;

buffer.RedMax = b[5] | b[4] << 8;

buffer.GreenMax = b[7] | b[6] << 8;

buffer.BlueMax = b[9] | b[8] << 8;

buffer.RedShift = b[10];

buffer.GreenShift = b[11];

buffer.BlueShift = b[12];

}

// Last 3 bytes are padding, ignore

return buffer;

}

}

}