private static Surface RenderGlyph(FT_Bitmap bitmap, byte alpha)
{
if (bitmap.rows == 0 || bitmap.pitch == 0)
{
return(new Surface(0, 0));
}
var bytes = new byte[bitmap.rows * bitmap.pitch];
Marshal.Copy(bitmap.buffer, bytes, 0, bytes.Length);
return(new Surface((int)bitmap.width, (int)bitmap.rows, TransformGlyphBytes(bytes, alpha)));
Pixel[] TransformGlyphBytes(byte[] input, byte a)
{
var output = new Pixel[input.Length];
for (int i = 0; i < input.Length; i++)
{
output[i].R = input[i];
output[i].G = input[i];
output[i].B = input[i];
output[i].A = input[i] != 0 ? (byte)255 : alpha;
}
return(output);
}
}
public CharacterInfo RequestCharacterInfo(int charactorCode)
{
var glyphIndex = FT.FT_Get_Char_Index(face.Face, (uint)charactorCode);
if (glyphIndex == 0)
{
return(null);
}
FT_Error error;
error = FT.FT_Load_Glyph(face.Face, glyphIndex, FT.FT_LOAD_DEFAULT);
if (error != FT_Error.FT_Err_Ok)
{
throw new FreeTypeException(error);
}
FT_Render_Mode renderMode = antialias ? FT_Render_Mode.FT_RENDER_MODE_NORMAL : FT_Render_Mode.FT_RENDER_MODE_MONO;
IntPtr pGlyphSlot;
unsafe
{
pGlyphSlot = (IntPtr)face.GlyphSlot;
}
error = FT.FT_Render_Glyph(pGlyphSlot, renderMode);
if (error != FT_Error.FT_Err_Ok)
{
throw new FreeTypeException(error);
}
FT_GlyphSlotRec glyphSlot = (FT_GlyphSlotRec)Marshal.PtrToStructure(pGlyphSlot, typeof(FT_GlyphSlotRec));
FT_Bitmap bitmap = glyphSlot.bitmap;
if (bitmap.buffer == IntPtr.Zero)
{
return(new CharacterInfo(this, charactorCode, new Vector2((int)glyphSlot.advance.x >> 6, (int)glyphSlot.advance.y >> 6)));
}
Texture texture = Font.atlas.Allocate(bitmap.width, bitmap.rows);
switch ((FT_Pixel_Mode)bitmap.pixel_mode)
{
case FT_Pixel_Mode.FT_PIXEL_MODE_GRAY:
{
uint length = bitmap.width * bitmap.rows;
byte[] buffer = new Byte[length];
Marshal.Copy(bitmap.buffer, buffer, 0, (int)length);
Color[] pixels = new Color[length];
int count = 0;
for (int y = (int)bitmap.rows - 1; y >= 0; y--)
{
for (int x = 0; x < bitmap.width; x++)
{
int index = y * (int)bitmap.width + x;
pixels[count] = new Color {
r = 1, g = 1, b = 1, a = (float)buffer[index] / 255.0f
};
count++;
}
}
texture.SetPixels(pixels);
}
break;
case FT_Pixel_Mode.FT_PIXEL_MODE_MONO:
{
uint length = bitmap.width * bitmap.rows;
byte[] buffer = new Byte[bitmap.pitch * bitmap.rows];
Marshal.Copy(bitmap.buffer, buffer, 0, (int)buffer.Length);
Color[] pixels = new Color[length];
int count = 0;
for (int y = (int)bitmap.rows - 1; y >= 0; y--)
{
for (int x = 0; x < bitmap.width; x++)
{
int index = y * bitmap.pitch + (int)(x / 8);
byte group = buffer[index];
float pixel = (group & (1 << (7 - x % 8))) > 0 ? 255.0f : 0;
pixels[count] = new Color {
r = 1, g = 1, b = 1, a = pixel / 255.0f
};
count++;
}
}
texture.SetPixels(pixels);
}
break;
default:
throw new NotImplementedException(string.Format("Pixel mode ({0})", bitmap.pixel_mode.ToString()));
}
return(new CharacterInfo(
this,
charactorCode,
new Vector2((float)glyphSlot.advance.x / (float)(1 << 6), (float)glyphSlot.advance.y / (float)(1 << 6)),
texture,
new Vector2(glyphSlot.bitmap_left, glyphSlot.bitmap_top)
));
}
