/// <summary><para>
/// Embolden an outline. The new outline will be at most 4 times ‘strength’ pixels wider and higher. You may
/// think of the left and bottom borders as unchanged.
/// </para><para>
/// Negative ‘strength’ values to reduce the outline thickness are possible also.
/// </para></summary>
/// <remarks><para>
/// The used algorithm to increase or decrease the thickness of the glyph doesn't change the number of points;
/// this means that certain situations like acute angles or intersections are sometimes handled incorrectly.
/// </para><para>
/// If you need ‘better’ metrics values you should call <see cref="GetCBox"/> or <see cref="GetBBox"/>.
/// </para></remarks>
/// <example>
/// FT_Load_Glyph( face, index, FT_LOAD_DEFAULT );
/// if ( face->slot->format == FT_GLYPH_FORMAT_OUTLINE )
/// FT_Outline_Embolden( &face->slot->outline, strength );
/// </example>
/// <param name="strength">How strong the glyph is emboldened. Expressed in 26.6 pixel format.</param>
public void Embolden(Fixed26Dot6 strength)
{
Error err = FT.FT_Outline_Embolden(Reference, (IntPtr)strength.Value);
if (err != Error.Ok)
{
throw new FreeTypeException(err);
}
}
/// <summary><para>
/// Embolden an outline. The new outline will be at most 4 times ‘strength’ pixels wider and higher. You may
/// think of the left and bottom borders as unchanged.
/// </para><para>
/// Negative ‘strength’ values to reduce the outline thickness are possible also.
/// </para></summary>
/// <remarks><para>
/// The used algorithm to increase or decrease the thickness of the glyph doesn't change the number of points;
/// this means that certain situations like acute angles or intersections are sometimes handled incorrectly.
/// </para><para>
/// If you need ‘better’ metrics values you should call <see cref="GetCBox"/> or <see cref="GetBBox"/>.
/// </para></remarks>
/// <example>
/// FT_Load_Glyph( face, index, FT_LOAD_DEFAULT );
/// if ( face->slot->format == FT_GLYPH_FORMAT_OUTLINE )
/// FT_Outline_Embolden( &face->slot->outline, strength );
/// </example>
/// <param name="strength">How strong the glyph is emboldened. Expressed in 26.6 pixel format.</param>
public void Embolden(Fixed26Dot6 strength)
{
if (disposed)
{
throw new ObjectDisposedException("Outline", "Cannot access a disposed object.");
}
Error err = FT.FT_Outline_Embolden(reference, (IntPtr)strength.Value);
if (err != Error.Ok)
{
throw new FreeTypeException(err);
}
}
/// <summary>
/// Embolden a bitmap. The new bitmap will be about ‘xStrength’ pixels wider and ‘yStrength’ pixels higher. The
/// left and bottom borders are kept unchanged.
/// </summary>
/// <remarks><para>
/// The current implementation restricts ‘xStrength’ to be less than or equal to 8 if bitmap is of pixel_mode
/// <see cref="SharpFont.PixelMode.Mono"/>.
/// </para><para>
/// If you want to embolden the bitmap owned by a <see cref="GlyphSlot"/>, you should call
/// <see cref="GlyphSlot.OwnBitmap"/> on the slot first.
/// </para></remarks>
/// <param name="library">A handle to a library object.</param>
/// <param name="xStrength">
/// How strong the glyph is emboldened horizontally. Expressed in 26.6 pixel format.
/// </param>
/// <param name="yStrength">
/// How strong the glyph is emboldened vertically. Expressed in 26.6 pixel format.
/// </param>
public void Embolden(Library library, Fixed26Dot6 xStrength, Fixed26Dot6 yStrength)
{
if (library == null)
{
throw new ArgumentNullException("library");
}
Error err = FT.FT_Bitmap_Embolden(library.Reference, Reference, (IntPtr)xStrength.Value, (IntPtr)yStrength.Value);
if (err != Error.Ok)
{
throw new FreeTypeException(err);
}
}
/// <summary>
/// Embolden a bitmap. The new bitmap will be about ‘xStrength’ pixels wider and ‘yStrength’ pixels higher. The
/// left and bottom borders are kept unchanged.
/// </summary>
/// <remarks><para>
/// The current implementation restricts ‘xStrength’ to be less than or equal to 8 if bitmap is of pixel_mode
/// <see cref="SharpFont.PixelMode.Mono"/>.
/// </para><para>
/// If you want to embolden the bitmap owned by a <see cref="GlyphSlot"/>, you should call
/// <see cref="GlyphSlot.OwnBitmap"/> on the slot first.
/// </para></remarks>
/// <param name="library">A handle to a library object.</param>
/// <param name="xStrength">
/// How strong the glyph is emboldened horizontally. Expressed in 26.6 pixel format.
/// </param>
/// <param name="yStrength">
/// How strong the glyph is emboldened vertically. Expressed in 26.6 pixel format.
/// </param>
public void Embolden(Library library, Fixed26Dot6 xStrength, Fixed26Dot6 yStrength)
{
if (disposed)
{
throw new ObjectDisposedException("FTBitmap", "Cannot access a disposed object.");
}
if (library == null)
{
throw new ArgumentNullException("library");
}
Error err = FT.FT_Bitmap_Embolden(library.Reference, Reference, (IntPtr)xStrength.Value, (IntPtr)yStrength.Value);
if (err != Error.Ok)
{
throw new FreeTypeException(err);
}
}
/// <summary>
/// Initializes a new instance of the <see cref="FTVector26Dot6"/> struct.
/// </summary>
/// <param name="x">The horizontal coordinate.</param>
/// <param name="y">The vertical coordinate.</param>
public FTVector26Dot6(Fixed26Dot6 x, Fixed26Dot6 y)
: this()
{
this.x = (IntPtr)x.Value;
this.y = (IntPtr)y.Value;
}
private Glyph LoadGlyph(int codePoint, int characterSize, bool bold, float outlineThickness)
{
Glyph glyph = new Glyph();
if (_face == null)
{
return(null);
}
// Set the character size
if (!SetCurrentSize(characterSize))
{
return(glyph);
}
// Load the glyph corresponding to the code point
var flags = LoadFlags.ForceAutohint;
if (outlineThickness != 0)
{
flags |= LoadFlags.NoBitmap;
}
_face.LoadChar((uint)codePoint, flags, SharpFont.LoadTarget.Normal);
// Retrieve the glyph
SharpFont.Glyph glyphDesc = _face.Glyph.GetGlyph();
// Apply bold if necessary -- first technique using outline (highest quality)
SharpFont.Fixed26Dot6 weight = new SharpFont.Fixed26Dot6(1);
bool outline = glyphDesc.Format == SharpFont.GlyphFormat.Outline;
if (outline)
{
if (bold)
{
SharpFont.OutlineGlyph outlineGlyph = glyphDesc.ToOutlineGlyph();
outlineGlyph.Outline.Embolden(weight);
}
if (outlineThickness != 0)
{
_stroker.Set((int)(outlineThickness * Fixed26Dot6.FromInt32(1).Value),
StrokerLineCap.Round, StrokerLineJoin.Round, Fixed16Dot16.FromSingle(0));
// This function returning a new instance of Glyph
// Because the pointer may changed upon applying stroke to the glyph
glyphDesc = glyphDesc.Stroke(_stroker, false);
}
}
// Convert the glyph to a bitmap (i.e. rasterize it)
glyphDesc.ToBitmap(SharpFont.RenderMode.Normal, new FTVector26Dot6(0, 0), true);
SharpFont.FTBitmap bitmap = glyphDesc.ToBitmapGlyph().Bitmap;
// Apply bold if necessary -- fallback technique using bitmap (lower quality)
if (!outline)
{
if (bold)
{
bitmap.Embolden(_library, weight, weight);
}
if (outlineThickness != 0)
{
Logger.Warning("Failed to outline glyph (no fallback available)");
}
}
// Compute the glyph's advance offset
glyph.Advance = _face.Glyph.Metrics.HorizontalAdvance.ToSingle();
if (bold)
{
glyph.Advance += weight.ToSingle();
}
int width = bitmap.Width;
int height = bitmap.Rows;
if ((width > 0) && (height > 0))
{
// Leave a small padding around characters, so that filtering doesn't
// pollute them with pixels from neighbors
int padding = 1;
// Get the glyphs page corresponding to the character size
Page page = _pages[characterSize];
// Find a good position for the new glyph into the texture
glyph.TexCoords = FindGlyphRectangle(page, width + 2 * padding, height + 2 * padding);
var texRect = glyph.TexCoords;
// Make sure the texture data is positioned in the center
// of the allocated texture rectangle
glyph.TexCoords = new Rectangle(texRect.X + padding, texRect.Y + padding,
texRect.Width - 2 * padding, texRect.Height - 2 * padding);
// Compute the glyph's bounding box
float boundsX = (float)(_face.Glyph.Metrics.HorizontalBearingX);
float boundsY = -(float)(_face.Glyph.Metrics.HorizontalBearingY);
float boundsWidth = (float)(_face.Glyph.Metrics.Width) + outlineThickness * 2;
float boundsHeight = (float)(_face.Glyph.Metrics.Height) + outlineThickness * 2;
glyph.Bounds = new RectangleF(boundsX, boundsY, boundsWidth, boundsHeight);
// Extract the glyph's pixels from the bitmap
byte[] pixelBuffer = new byte[width * height * 4];
for (int i = 0; i < pixelBuffer.Length; i++)
{
pixelBuffer[i] = 255;
}
unsafe
{
byte *pixels = (byte *)bitmap.Buffer.ToPointer();
if (bitmap.PixelMode == SharpFont.PixelMode.Mono)
{
// Pixels are 1 bit monochrome values
for (int y = 0; y < height; ++y)
{
for (int x = 0; x < width; ++x)
{
// The color channels remain white, just fill the alpha channel
int index = (x + y * width) * 4 + 3;
pixelBuffer[index] = (byte)((((pixels[x / 8]) & (1 << (7 - (x % 8)))) > 0) ? 255 : 0);
}
pixels += bitmap.Pitch;
}
}
else
{
// Pixels are 8 bits gray levels
for (int y = 0; y < height; ++y)
{
for (int x = 0; x < width; ++x)
{
// The color channels remain white, just fill the alpha channel
int index = (x + y * width) * 4 + 3;
pixelBuffer[index] = pixels[x];
}
pixels += bitmap.Pitch;
}
}
}
// Write the pixels to the texture
int tx = glyph.TexCoords.Left;
int ty = glyph.TexCoords.Top;
int tw = glyph.TexCoords.Width;
int th = glyph.TexCoords.Height;
page.texture.Update(pixelBuffer, tx, ty, tw, th);
}
// Delete the FT glyph
glyphDesc.Dispose();
return(glyph);
}
