/// <overloads>
/// <summary>
/// Initializes a new instance of the <see cref="Image"/> class.
/// </summary>
/// </overloads>
///
/// <summary>
/// Initializes a new, empty instance of the <see cref="Image"/> class.
/// </summary>
/// <param name="width">The width in pixels.</param>
/// <param name="height">The height in pixels.</param>
/// <param name="format">The texture format.</param>
/// <exception cref="ArgumentOutOfRangeException">
/// <paramref name="width"/> or <paramref name="height"/> is 0 or negative.
/// </exception>
/// <exception cref="ArgumentException">
/// <paramref name="format"/> is invalid.
/// </exception>
public Image(int width, int height, DataFormat format)
{
if (width <= 0)
{
throw new ArgumentOutOfRangeException("width", "Image size must not be negative or 0.");
}
if (height <= 0)
{
throw new ArgumentOutOfRangeException("height", "Image size must not be negative or 0.");
}
if (!TextureHelper.IsValid(format))
{
throw new ArgumentException("Invalid texture format.", "format");
}
int rowPitch, slicePitch;
TextureHelper.ComputePitch(format, width, height, out rowPitch, out slicePitch);
Width = width;
Height = height;
Format = format;
RowPitch = rowPitch;
_data = new byte[slicePitch];
}
/// <summary>
/// Initializes a new instance of the <see cref="Image"/> class with the specified data.
/// </summary>
/// <param name="width">The width in pixels.</param>
/// <param name="height">The height in pixels.</param>
/// <param name="format">The texture format.</param>
/// <param name="data">The contents of the image.</param>
/// <exception cref="ArgumentException">
/// <paramref name="format"/> is invalid, or <paramref name="data"/> has wrong size.
/// </exception>
/// <exception cref="ArgumentNullException">
/// <paramref name="data"/> is <see langword="null"/>.
/// </exception>
/// <exception cref="ArgumentOutOfRangeException">
/// <paramref name="width"/> or <paramref name="height"/>is 0 or negative.
/// </exception>
public Image(int width, int height, DataFormat format, byte[] data)
{
if (width <= 0)
{
throw new ArgumentOutOfRangeException("width", "Image size must not be negative or 0.");
}
if (height <= 0)
{
throw new ArgumentOutOfRangeException("height", "Image size must not be negative or 0.");
}
if (!TextureHelper.IsValid(format))
{
throw new ArgumentException("Invalid texture format.", "format");
}
if (data == null)
{
throw new ArgumentNullException("data");
}
int rowPitch, slicePitch;
TextureHelper.ComputePitch(format, width, height, out rowPitch, out slicePitch);
if (data.Length != slicePitch)
{
throw new ArgumentException(string.Format("Buffer has invalid size. Expected size: {0} bytes; Actual size: {1}", slicePitch, data.Length));
}
Width = width;
Height = height;
Format = format;
RowPitch = rowPitch;
_data = data;
}
/// <summary>
/// Determines the number of image array entries and pixel size.
/// </summary>
/// <param name="description">The texture description.</param>
/// <param name="nImages">The number of entries in the image array.</param>
/// <param name="pixelSize">The total pixel size.</param>
private static void DetermineImages(TextureDescription description, out int nImages, out int pixelSize)
{
Debug.Assert(description.Width > 0 && description.Height > 0 && description.Depth > 0);
Debug.Assert(description.ArraySize > 0);
Debug.Assert(description.MipLevels > 0);
pixelSize = 0;
nImages = 0;
switch (description.Dimension)
{
case TextureDimension.Texture1D:
case TextureDimension.Texture2D:
case TextureDimension.TextureCube:
for (int item = 0; item < description.ArraySize; item++)
{
int w = description.Width;
int h = description.Height;
for (int level = 0; level < description.MipLevels; level++)
{
int rowPitch, slicePitch;
TextureHelper.ComputePitch(description.Format, w, h, out rowPitch, out slicePitch, ComputePitchFlags.None);
pixelSize += slicePitch;
nImages++;
if (h > 1)
h >>= 1;
if (w > 1)
w >>= 1;
}
}
break;
case TextureDimension.Texture3D:
{
int w = description.Width;
int h = description.Height;
int d = description.Depth;
for (int level = 0; level < description.MipLevels; level++)
{
int rowPitch, slicePitch;
TextureHelper.ComputePitch(description.Format, w, h, out rowPitch, out slicePitch, ComputePitchFlags.None);
for (int slice = 0; slice < d; slice++)
{
pixelSize += slicePitch;
nImages++;
}
if (h > 1)
h >>= 1;
if (w > 1)
w >>= 1;
if (d > 1)
d >>= 1;
}
}
break;
default:
Debug.Fail("Unexpected texture dimension");
break;
}
}