public static unsafe DemoImage LoadImage(string filePathName, bool flipVertical)
{
var imageClass = UIImage.FromFile(filePathName);
var cgImage = imageClass.CGImage;
if(cgImage == null)
{
return null;
}
var image = new DemoImage();
image.Width = cgImage.Width;
image.Height = cgImage.Height;
image.RowByteSize = image.Width * 4;
image.Data = new byte[cgImage.Height * image.RowByteSize];
image.Format = PixelInternalFormat.Rgba;
image.Type = PixelType.UnsignedByte;
fixed (byte *ptr = &image.Data [0]){
using(var context = new CGBitmapContext((IntPtr) ptr, image.Width, image.Height, 8, image.RowByteSize, cgImage.ColorSpace, CGImageAlphaInfo.NoneSkipLast))
{
context.SetBlendMode(CGBlendMode.Copy);
if(flipVertical)
{
context.TranslateCTM(0.0f, (float)image.Height);
context.ScaleCTM(1.0f, -1.0f);
}
context.DrawImage(new RectangleF(0f, 0f, image.Width, image.Height), cgImage);
}
}
return image;
}
int BuildTexture(DemoImage image)
{
int texName = 0;
// Create a texture object to apply to model
GL.GenTextures(1, out texName);
GL.BindTexture(TextureTarget.Texture2D, texName);
// Set up filter and wrap modes for this texture object
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)All.ClampToEdge);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)All.ClampToEdge);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)All.Linear);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)All.LinearMipmapLinear);
// Indicate that pixel rows are tightly packed
// (defaults to stride of 4 which is kind of only good for
// RGBA or FLOAT data types)
GL.PixelStore(PixelStoreParameter.UnpackAlignment, 1);
// Allocate and load image data into texture
GL.TexImage2D<byte>(TextureTarget.Texture2D, 0, image.Format, image.Width, image.Height, 0,
(PixelFormat)Enum.ToObject(typeof(PixelFormat), (int)image.Format), image.Type, image.Data);
// Create mipmaps for this texture for better image quality
GL.GenerateMipmap(TextureTarget.Texture2D);
GetGLError();
return texName;
}