/*
* Draw text: the text by default lies in the x,y plane and along the x axis in the positive direction.
* It can be tilted about the x-axis using the SetTiltInRadians method.
* Returns the string length in pixels.
*/
public void DrawText(float x, float y, float z, string text)
{
// Make this texture active
GL.Enable(EnableCap.Texture2D);
GL.Enable(EnableCap.Blend);
GL.BlendFunc(BlendingFactor.SrcAlpha, BlendingFactor.OneMinusSrcAlpha);
GL.BindTexture(TextureTarget.Texture2D, FontTextureID);
GL.Begin(PrimitiveType.Quads);
GL.Color3(Color.Transparent);
float xScreen = x;
float yScreen = y;
foreach (var idx in text)
{
TextureSettings.GlyphInfo glyphoInfo = _textureSettings.GlyphInfoArray[idx];
float xTexture = (float)glyphoInfo.X / (float)TextureWidth;
float yTexture = (float)glyphoInfo.Y / (float)TextureHeight;
float widthTexture = (float)glyphoInfo.Width / (float)TextureWidth;
float heightTexture = (float)glyphoInfo.Height / (float)TextureHeight;
float dy = (float)(glyphoInfo.Height * _cosineTilt);
float dz = -(float)(glyphoInfo.Height * _sineTilt);
GL.TexCoord3(xTexture, yTexture, z);
GL.Vertex3(xScreen, yScreen + dy, z + dz);
GL.TexCoord3(xTexture + widthTexture, yTexture, z);
GL.Vertex3(xScreen + glyphoInfo.Width, yScreen + dy, z + dz);
GL.TexCoord3(xTexture + widthTexture, yTexture + heightTexture, z);
GL.Vertex3(xScreen + glyphoInfo.Width, yScreen, z);
GL.TexCoord3(xTexture, yTexture + heightTexture, z);
GL.Vertex3(xScreen, yScreen, z);
xScreen += glyphoInfo.Width;
}
GL.End();
GL.Disable(EnableCap.Texture2D);
GL.Disable(EnableCap.Blend);
}
/*
* Purpose: Creates a bitmap image of the character set and saves it as a file => [APP_DATA]\local\Temp\font_1.png
*
* We do this so that the bitmap can be loaded
*/
private void GenerateFontImage()
{
System.Drawing.Font font;
if (!string.IsNullOrWhiteSpace(_textureSettings.FromFile))
{
var collection = new System.Drawing.Text.PrivateFontCollection();
collection.AddFontFile(_textureSettings.FromFile);
var fontFamily = new System.Drawing.FontFamily(System.IO.Path.GetFileNameWithoutExtension(_textureSettings.FromFile), collection);
font = new System.Drawing.Font(fontFamily, _textureSettings.FontSize);
}
else
{
font = new System.Drawing.Font(new System.Drawing.FontFamily(_textureSettings.FontName), _textureSettings.FontSize, FontStyle.Bold);
}
// Measure the size of each character when written to a bitmap
using (System.Drawing.Bitmap bitmap = new Bitmap(100, 100, System.Drawing.Imaging.PixelFormat.Format32bppArgb))
{
using (var graphics = System.Drawing.Graphics.FromImage(bitmap))
{
char c = (char)0;
float previousY = 0;
float lineHeight = 0;
for (int p = 0; p < _textureSettings.GlyphLineCount; p++)
{
float previousX = 0;
for (int n = 0; n < _textureSettings.GlyphsPerLine; n++, ++c)
{
SizeF size = graphics.MeasureString(c.ToString(), font, 0);
// The next step is purely empirical => remove superfluous padding
size = new SizeF(size.Width - _textureSettings.FontSize / 6, size.Height - _textureSettings.FontSize / 6);
if ((p == 0) && (n == 0))
{
lineHeight = size.Height;
}
TextureSettings.GlyphInfo glyphoInfo = new TextureSettings.GlyphInfo();
_textureSettings.GlyphInfoArray[c] = glyphoInfo;
glyphoInfo.X = previousX;
glyphoInfo.Y = previousY;
glyphoInfo.Width = size.Width;
glyphoInfo.Height = size.Height;
previousX += size.Width;
TextureWidth = System.Math.Max(TextureWidth, (int)(previousX + 1));
}
previousY += lineHeight;
TextureHeight = System.Math.Max(TextureHeight, (int)(previousY + 1));
}
}
}
// Now create the character bitmap
using (System.Drawing.Bitmap bitmap = new System.Drawing.Bitmap(TextureWidth, TextureHeight, System.Drawing.Imaging.PixelFormat.Format32bppArgb))
{
using (var graphics = System.Drawing.Graphics.FromImage(bitmap))
{
graphics.Clear(_backgroundColour);
if (_textureSettings.BitmapFont)
{
graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.None;
graphics.TextRenderingHint = System.Drawing.Text.TextRenderingHint.SingleBitPerPixel;
}
else
{
graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
graphics.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAliasGridFit;
}
char c = (char)0;
for (int i = 0; i < 256; ++i, ++c)
{
TextureSettings.GlyphInfo glyphoInfo = _textureSettings.GlyphInfoArray[i];
graphics.DrawString(c.ToString(), font, new SolidBrush(_textColour), glyphoInfo.X, glyphoInfo.Y);
}
}
bitmap.Save(_textureSettings.FontBitmapFilename);
}
}
