public static unsafe void CompareMetricsWithStb(Font f, DrawableFontAtlas atlas, StbTrueType.stbtt_fontinfo stbFont)
{
var pc = new StbTrueType.stbtt_pack_context();
StbTrueType.stbtt_PackBegin(pc, (byte *)0, 512, 512, 512, 1, null);
var cd = new StbTrueType.stbtt_packedchar[f.LastCharIndex + 1];
StbTrueType.stbrp_rect[] rects;
fixed(StbTrueType.stbtt_packedchar *charDataPtr = &cd[0])
{
var range = new StbTrueType.stbtt_pack_range
{
first_unicode_codepoint_in_range = 0,
array_of_unicode_codepoints = null,
num_chars = (int)f.LastCharIndex + 1,
chardata_for_range = charDataPtr,
font_size = -atlas.FontSize
};
rects = new StbTrueType.stbrp_rect[f.LastCharIndex + 1];
fixed(StbTrueType.stbrp_rect *rectPtr = &rects[0])
{
int n = StbTrueType.stbtt_PackFontRangesGatherRects(pc, stbFont, &range, 1, rectPtr);
StbTrueType.stbtt_PackFontRangesPackRects(pc, rectPtr, n);
}
}
foreach ((char charIndex, DrawableGlyph atlasGlyph) in atlas.Glyphs)
{
FontGlyph glyph = atlasGlyph.FontGlyph;
var advance = 0;
var bearing = 0;
StbTrueType.stbtt_GetCodepointHMetrics(stbFont, charIndex, &advance, &bearing);
Assert.True(advance == glyph.AdvanceWidth);
Assert.True(bearing == glyph.LeftSideBearing || glyph.LeftSideBearing == 0); // stb has junk data beyond valid
var minX = 0;
var maxX = 0;
var minY = 0;
var maxY = 0;
StbTrueType.stbtt_GetCodepointBitmapBoxSubpixel(stbFont, charIndex, atlas.RenderScale, atlas.RenderScale, 0, 0, &minX, &minY, &maxX, &maxY);
Rectangle bbox = glyph.GetBBox(atlas.RenderScale);
Assert.Equal(minX, bbox.X);
Assert.Equal(minY, bbox.Y);
Assert.Equal(maxX, bbox.Width);
Assert.Equal(maxY, bbox.Height);
Rectangle drawBox = new Rectangle(0, 0, bbox.Width - bbox.X, bbox.Height - bbox.Y);
drawBox.Size += Vector2.One; // Add padding from stb
StbTrueType.stbrp_rect rect = rects[charIndex];
Assert.Equal(rect.w, drawBox.Width);
Assert.Equal(rect.h, drawBox.Height);
}
}
public void Begin(int width, int height)
{
bitmapWidth = width;
bitmapHeight = height;
_bitmap = new byte[width * height];
_context = new StbTrueType.stbtt_pack_context();
fixed(byte *pixelsPtr = _bitmap)
{
StbTrueType.stbtt_PackBegin(_context, pixelsPtr, width, height, width, 1, null);
}
_glyphs = new Dictionary <int, GlyphInfo>();
}
public static unsafe DrawableFontAtlas RenderFontStbPacked(byte[] ttf, float fontSize, Vector2 atlasSize, int numChars, Font f, out StbTrueType.stbtt_fontinfo fontInfo)
{
var atlasObj = new DrawableFontAtlas(f, fontSize);
fontSize = atlasObj.FontSize;
fontInfo = new StbTrueType.stbtt_fontinfo();
fixed(byte *ttPtr = &ttf[0])
{
StbTrueType.stbtt_InitFont(fontInfo, ttPtr, 0);
float scaleFactor = StbTrueType.stbtt_ScaleForMappingEmToPixels(fontInfo, fontSize);
int ascent, descent, lineGap;
StbTrueType.stbtt_GetFontVMetrics(fontInfo, &ascent, &descent, &lineGap);
atlasSize *= 3; // Needs to be big as the packing sucks, and glyphs getting cut out messes with the tests.
var pixels = new byte[(int)atlasSize.X * (int)atlasSize.Y];
var pc = new StbTrueType.stbtt_pack_context();
fixed(byte *pixelsPtr = pixels)
{
StbTrueType.stbtt_PackBegin(pc, pixelsPtr, (int)atlasSize.X, (int)atlasSize.Y, (int)atlasSize.X, 1, null);
}
var cd = new StbTrueType.stbtt_packedchar[numChars];
fixed(StbTrueType.stbtt_packedchar *charPtr = cd)
{
StbTrueType.stbtt_PackFontRange(pc, ttPtr, 0, -fontSize, 0, numChars, charPtr);
}
StbTrueType.stbtt_PackEnd(pc);
for (var i = 0; i < cd.Length; ++i)
{
var atlasGlyph = DrawableGlyph.CreateForTest(cd[i].xadvance, cd[i].xoff, cd[i].x1 - cd[i].x0, cd[i].y1 - cd[i].y0);
atlasGlyph.GlyphUV = new Rectangle(cd[i].x0, cd[i].y0, atlasGlyph.Width, atlasGlyph.Height);
atlasObj.Glyphs[(char)i] = atlasGlyph;
}
}
return(atlasObj);
}
public static TtfFontBakerResult Bake(byte[] ttf, float fontPixelHeight,
int bitmapWidth, int bitmapHeight,
IEnumerable <CharacterRange> characterRanges)
{
if (ttf == null || ttf.Length == 0)
{
throw new ArgumentNullException(nameof(ttf));
}
if (fontPixelHeight <= 0)
{
throw new ArgumentOutOfRangeException(nameof(fontPixelHeight));
}
if (bitmapWidth <= 0)
{
throw new ArgumentOutOfRangeException(nameof(bitmapWidth));
}
if (bitmapHeight <= 0)
{
throw new ArgumentOutOfRangeException(nameof(bitmapHeight));
}
if (characterRanges == null)
{
throw new ArgumentNullException(nameof(characterRanges));
}
if (!characterRanges.Any())
{
throw new ArgumentException("characterRanges must have a least one value.");
}
byte[] pixels;
var glyphs = new Dictionary <int, GlyphInfo>();
fixed(byte *ttfPtr = ttf)
{
StbTrueType.stbtt_fontinfo fontInfo = new StbTrueType.stbtt_fontinfo();
if (StbTrueType.stbtt_InitFont(fontInfo, ttfPtr, 0) == 0)
{
throw new Exception("Failed to init font.");
}
float scaleFactor = StbTrueType.stbtt_ScaleForPixelHeight(fontInfo, fontPixelHeight);
int ascent, descent, lineGap;
StbTrueType.stbtt_GetFontVMetrics(fontInfo, &ascent, &descent, &lineGap);
pixels = new byte[bitmapWidth * bitmapHeight];
StbTrueType.stbtt_pack_context pc = new StbTrueType.stbtt_pack_context();
fixed(byte *pixelsPtr = pixels)
{
StbTrueType.stbtt_PackBegin(pc, pixelsPtr, bitmapWidth,
bitmapHeight, bitmapWidth, 1, null);
}
foreach (var range in characterRanges)
{
if (range.Start > range.End)
{
continue;
}
var cd = new StbTrueType.stbtt_packedchar[range.End - range.Start + 1];
fixed(StbTrueType.stbtt_packedchar *chardataPtr = cd)
{
StbTrueType.stbtt_PackFontRange(pc, ttfPtr, 0, fontPixelHeight,
range.Start,
range.End - range.Start + 1,
chardataPtr);
}
for (var i = 0; i < cd.Length; ++i)
{
var yOff = cd[i].yoff;
yOff += ascent * scaleFactor;
var glyphInfo = new GlyphInfo
{
X = cd[i].x0,
Y = cd[i].y0,
Width = cd[i].x1 - cd[i].x0,
Height = cd[i].y1 - cd[i].y0,
XOffset = (int)cd[i].xoff,
YOffset = (int)Math.Round(yOff),
XAdvance = (int)Math.Round(cd[i].xadvance)
};
glyphs[(char)(i + range.Start)] = glyphInfo;
}
}
}
return(new TtfFontBakerResult(glyphs, fontPixelHeight, pixels, bitmapWidth, bitmapHeight));
}