/// <summary>
/// generates new mipmaps
/// </summary>
public TextureArray2D GenerateMipmapLevels(int levels)
{
Debug.Assert(!HasMipmaps);
// create a texture with the same format and more mipmaps
var newTex = new TextureArray2D(nLayer, levels, internalFormat, width, height, IsSrgb);
// copy image data of first level
GL.CopyImageSubData(id, ImageTarget.Texture2DArray, 0, 0, 0, 0,
newTex.id, ImageTarget.Texture2DArray, 0, 0, 0, 0, width, height, nLayer);
newTex.GenerateMipmaps();
return(newTex);
}
/// <summary>
/// creates a new texture that has only one mipmap level
/// </summary>
/// <param name="level">mipmap level to clone</param>
/// <returns></returns>
public TextureArray2D CloneMipmapLevel(int level)
{
Debug.Assert(level < nMipmaps);
Debug.Assert(level >= 0);
GL.GetTexLevelParameter(TextureTarget.Texture2DArray, level, GetTextureParameter.TextureWidth, out int lvlWidth);
GL.GetTexLevelParameter(TextureTarget.Texture2DArray, level, GetTextureParameter.TextureHeight, out int lvlHeight);
var newTex = new TextureArray2D(nLayer, 1, internalFormat, lvlWidth, lvlHeight, IsSrgb);
// copy data of first mipmap level
GL.CopyImageSubData(id, ImageTarget.Texture2DArray, level, 0, 0, 0,
newTex.id, ImageTarget.Texture2DArray, 0, 0, 0, 0, lvlWidth, lvlHeight, nLayer);
return(newTex);
}
/// <summary>
/// performs a deep gpu copy of the textures
/// </summary>
/// <returns></returns>
public TextureArray2D Clone()
{
var newTex = new TextureArray2D(nLayer, nMipmaps, internalFormat, width, height, IsSrgb);
for (var level = 0; level < nMipmaps; ++level)
{
GL.GetTexLevelParameter(TextureTarget.Texture2DArray, level, GetTextureParameter.TextureWidth, out int lwidth);
GL.GetTexLevelParameter(TextureTarget.Texture2DArray, level, GetTextureParameter.TextureHeight, out int lheight);
GL.CopyImageSubData(id, ImageTarget.Texture2DArray, level, 0, 0, 0,
newTex.id, ImageTarget.Texture2DArray, level, 0, 0, 0,
lwidth, lheight, nLayer);
}
return(newTex);
}
