/// <summary>
/// Constructs a new instance.
/// </summary>
/// <param name="width">The width of the backing store in pixels.</param>
/// <param name="height">The height of the backing store in pixels.</param>
/// <param name="renderer">GWEN renderer.</param>
public TextRenderer(int width, int height, OpenTK renderer)
{
if (width <= 0)
throw new ArgumentOutOfRangeException("width");
if (height <= 0)
throw new ArgumentOutOfRangeException("height");
m_PixelData = Marshal.AllocHGlobal(width * height * 4);
m_Bitmap = new CGBitmapContext(m_PixelData, (nint)width, (nint)height, 8, 4 * (nint)width, CGColorSpace.CreateDeviceRGB(), CGBitmapFlags.PremultipliedLast | CGBitmapFlags.ByteOrder32Big);
m_Bitmap.SetTextDrawingMode(CGTextDrawingMode.Fill);
m_Bitmap.SetFillColor(new CGColor(1.0f, 1.0f, 1.0f, 1.0f));
m_Bitmap.ClearRect(new CGRect(0, 0, (nint)width, (nint)height));
m_Texture = new Texture(renderer) { Width = width, Height = height };
}
/// <summary>
/// Draws the specified string to the backing store.
/// </summary>
/// <param name="text">The <see cref="System.String"/> to draw.</param>
/// <param name="font">The <see cref="System.Drawing.Font"/> that will be used.</param>
/// <param name="brush">The <see cref="System.Drawing.Brush"/> that will be used.</param>
/// <param name="point">The location of the text on the backing store, in 2d pixel coordinates.
/// The origin (0, 0) lies at the top-left corner of the backing store.</param>
public void DrawString(CTLine text, Point point)
{
if (m_Bitmap != null)
{
m_Bitmap.TextPosition = new CGPoint(point.X, point.Y);
text.Draw(m_Bitmap);
// Fix ugly looking anti-alias
unsafe
{
// Pointer to the current pixel
uint* pPixel = (uint*)m_PixelData;
// Pointer value at which we terminate the loop (end of pixel data)
var pLastPixel = pPixel + (int)m_Bitmap.Width * (int)m_Bitmap.Height;
while (pPixel < pLastPixel)
{
// Get pixel data
uint pixelValue = *pPixel;
// Average RGB
uint brightness = (((pixelValue & 0xFF) + ((pixelValue >> 8) & 0xFF) + ((pixelValue >> 16) & 0xFF)) * 21845) >> 16; // Division by 3
// Use brightness for alpha value, set R, G, and B 0xff (white)
pixelValue = brightness << 24 | 0xffffff;
// Copy back to image
*pPixel = pixelValue;
// Next pixel
pPixel++;
}
}
OpenTK.LoadTextureInternal(m_Texture, m_Bitmap); // copy bitmap to gl texture
// Freeze texture to save memory
// Todo: Make optional
m_Bitmap.Dispose();
m_Bitmap = null;
Marshal.FreeHGlobal(m_PixelData);
m_PixelData = IntPtr.Zero;
}
}
