protected override void Download(PixelBox data)
{
#if GL_NV_get_tex_image
if (data.Width != Width || data.Height != Height || data.Depth != Depth)
{
throw new Core.AxiomException("only download of entire buffer is supported by GL");
}
GL.BindTexture(this.target, this.textureID);
if (PixelUtil.IsCompressed(data.Format))
{
if (data.Format != format || !data.IsConsecutive)
{
throw new Core.AxiomException("Compressed images must be consecutive, in the source format");
}
GL.GetCompressedTexImageNV(this.faceTarget, this.level, data.Data);
}
else
{
if ((data.Width * PixelUtil.GetNumElemBytes(data.Format) & 3) != 0)
{
//Standard alignment of 4 is not right
GL.PixelStore(Glenum.PackAlignment, 1);
}
//We can only get the entire texture
GL.GetTexImageNV(this.faceTarget, this.level, GLES2PixelUtil.GetGLOriginFormat(data.Format), GLES2PixelUtil.GetGLOriginDataType(data.Format), data.Data);
//Restore defaults
GL.PixelStore(Glenum.PackAlignment, 4);
}
#else
throw new Core.AxiomException("Downloading texture buffers is not supported by OpenGL ES");
#endif
}
