/// <summary>
/// Initializes a Font from the specified TTF file
/// </summary>
/// <param name="filename">The TTF to load.</param>
/// <param name="size">The size of the font in pt.</param>
public Font(string filename, float size)
{
// Check if the file exists
if (!File.Exists(filename))
{
throw new FileNotFoundException("Font not found: {0}", filename);
}
// Get the size
size26d6 = FTMath.To26Dot6(size);
// Get the font face and check for errors
var err = FT.FT_New_Face(freetype, filename, 0, out facePtr);
if (err != 0)
{
throw new Exception("Freetype Error");
}
// Set the char size
FT.FT_Set_Char_Size(facePtr,
FTMath.To26Dot6(0),
size26d6,
0,
96
);
// Calculate metrics
var faceRec = (FT.FaceRec)Marshal.PtrToStructure(facePtr, typeof(FT.FaceRec));
var szRec = (FT.SizeRec)Marshal.PtrToStructure(faceRec.size, typeof(FT.SizeRec));
lineHeight = (int)FTMath.From26Dot6(szRec.metrics.height);
pages.Add(GetNewTexture());
}
/// <summary>
/// Measure a string.
/// </summary>
/// <returns>The measurements.</returns>
/// <param name="text">Text.</param>
public Point MeasureString(string text)
{
// Skip empty strings
if (text == "")
{
return(Point.Empty);
}
// Get the codepoint iterator
var iter = new CodepointIterator(text);
// Initialize coordinates
float penX = 0, penY = 0;
// Iterate using the codepoint iterator
while (iter.Iterate())
{
// Get the current codepoint
var c = iter.Codepoint;
// Increment the y coords if the char is a linefeed
if (c == (uint)'\n')
{
penY += lineHeight;
penX = 0;
continue;
}
// Get the glyph
var glyph = GetGlyph(c);
if (glyph.Render)
{
penX += glyph.HorizontalAdvance;
penY += glyph.AdvanceY;
}
else
{
penX += glyph.AdvanceX;
penY += glyph.AdvanceY;
}
if (kerning && iter.Index < (iter.Count - 1))
{
var g2 = GetGlyph(iter.PeekNext());
FT.FT_Vector vec;
FT.FT_Get_Kerning(facePtr, glyph.CharIndex, g2.CharIndex, 2, out vec);
var krn = FTMath.From26Dot6(vec.x);
penX += krn;
}
}
penY = Math.Max(penY, LineHeight);
return(new Point((int)penX, (int)penY));
}
/// <summary>
/// Draw a string.
/// </summary>
/// <param name="spriteBatch">Sprite batch.</param>
/// <param name="text">Text.</param>
/// <param name="x">The x coordinate.</param>
/// <param name="y">The y coordinate.</param>
/// <param name="color">Color.</param>
public void DrawString(SpriteBatch spriteBatch, string text, int x, int y, Color4 color)
{
if (text == "") //Skip empty strings
{
return;
}
var iter = new CodepointIterator(text);
float penX = x, penY = y;
while (iter.Iterate())
{
uint c = iter.Codepoint;
if (c == (uint)'\n')
{
penY += lineHeight;
penX = x;
continue;
}
var glyph = GetGlyph(c);
if (glyph.Render)
{
spriteBatch.Draw(
glyph.Texture,
glyph.Rectangle,
new Rectangle(
(int)penX + glyph.XOffset,
(int)penY + (LineHeight - glyph.YOffset),
glyph.Rectangle.Width,
glyph.Rectangle.Height
),
color
);
penX += glyph.HorizontalAdvance;
penY += glyph.AdvanceY;
}
else
{
penX += glyph.AdvanceX;
penY += glyph.AdvanceY;
}
if (iter.Index < iter.Count - 1)
{
var g2 = GetGlyph(iter.PeekNext());
FT.FT_Vector vec;
FT.FT_Get_Kerning(facePtr, glyph.CharIndex, g2.CharIndex, 2, out vec);
var krn = FTMath.From26Dot6(vec.x);
penX += krn;
}
}
}
/// <summary>
/// Add a character.
/// </summary>
/// <param name="codePoint">Codepoint.</param>
unsafe void AddCharacter(uint codePoint)
{
// Handle Tab
if (codePoint == (uint)'\t')
{
var spaceGlyph = GetGlyph((uint)' ');
glyphs.Add(codePoint, new GlyphInfo(spaceGlyph.AdvanceX * 5, spaceGlyph.AdvanceY, spaceGlyph.CharIndex));
return;
}
// Check if Glyph exists
uint index = FT.FT_Get_Char_Index(facePtr, codePoint);
if (index == 0)
{
if (codePoint == (uint)'?')
{
throw new Exception("Font does not contain required character '?'");
}
glyphs.Add(codePoint, GetGlyph((uint)'?'));
return;
}
// Render the glyph
FT.FT_Load_Glyph(facePtr, index, FT.FT_LOAD_DEFAULT | FT.FT_LOAD_TARGET_NORMAL);
var faceRec = (FT.FaceRec)Marshal.PtrToStructure(facePtr, typeof(FT.FaceRec));
FT.FT_Render_Glyph(faceRec.glyph, FT.FT_RENDER_MODE_NORMAL);
var glyphRec = (FT.GlyphSlotRec)Marshal.PtrToStructure(faceRec.glyph, typeof(FT.GlyphSlotRec));
//Check for glyph that is only spacing
if (glyphRec.bitmap.width == 0 || glyphRec.bitmap.rows == 0)
{
glyphs.Add(codePoint, new GlyphInfo(
(int)Math.Ceiling(FTMath.From26Dot6(glyphRec.advance.x)),
(int)Math.Ceiling(FTMath.From26Dot6(glyphRec.advance.y)),
index
));
return;
}
var pixels = new RGBA[glyphRec.bitmap.width * glyphRec.bitmap.rows];
if (glyphRec.bitmap.pixel_mode == 2)
{
byte *data = (byte *)glyphRec.bitmap.buffer;
for (int i = 0; i < glyphRec.bitmap.width * glyphRec.bitmap.rows; i++)
{
// TODO: 4 bytes used for 1 byte of alpha data? investigate compression with GL_RED and shader.
pixels [i] = new RGBA(255, 255, 255, data [i]);
}
}
else
{
throw new NotImplementedException();
}
if (currentX + glyphRec.bitmap.width > TEXTURE_SIZE)
{
currentX = 0;
currentY += lineMax;
lineMax = 0;
}
if (currentY + glyphRec.bitmap.rows > TEXTURE_SIZE)
{
currentX = 0;
currentY = 0;
lineMax = 0;
pages.Add(GetNewTexture());
}
lineMax = Math.Max(lineMax, glyphRec.bitmap.rows);
var rect = new Rectangle(currentX, currentY, glyphRec.bitmap.width, glyphRec.bitmap.rows);
var tex = pages [pages.Count - 1];
tex.SetData(pixels, rect);
currentX += glyphRec.bitmap.width;
var glyphInfo = new GlyphInfo(
t: tex,
r: rect,
advX: (int)Math.Ceiling(FTMath.From26Dot6(glyphRec.advance.x)),
advY: (int)Math.Ceiling(FTMath.From26Dot6(glyphRec.advance.y)),
horzAdv: (int)Math.Ceiling(FTMath.From26Dot6(glyphRec.metrics.horiAdvance)),
xOff: glyphRec.bitmap_left,
yOff: glyphRec.bitmap_top,
idx: index
);
glyphs.Add(codePoint, glyphInfo);
}
