public unsafe void Append(TextAnalyzer analyzer, FontFace font, string text)
{
var layout = new TextLayout();
var format = new TextFormat {
Font = font,
Size = 32.0f
};
analyzer.AppendText(text, format);
analyzer.PerformLayout(0, 32, 1000, 1000, layout);
var memBlock = new MemoryBlock(text.Length * 6 * PosColorTexture.Layout.Stride);
var mem = (PosColorTexture*)memBlock.Data;
foreach (var thing in layout.Stuff) {
var width = thing.Width;
var height = thing.Height;
var region = new Vector4(thing.SourceX, thing.SourceY, width, height) / 4096;
var origin = new Vector2(thing.DestX, thing.DestY);
*mem++ = new PosColorTexture(origin + new Vector2(0, height), new Vector2(region.X, region.Y + region.W), unchecked((int)0xff000000));
*mem++ = new PosColorTexture(origin + new Vector2(width, height), new Vector2(region.X + region.Z, region.Y + region.W), unchecked((int)0xff000000));
*mem++ = new PosColorTexture(origin + new Vector2(width, 0), new Vector2(region.X + region.Z, region.Y), unchecked((int)0xff000000));
*mem++ = new PosColorTexture(origin, new Vector2(region.X, region.Y), unchecked((int)0xff000000));
count++;
}
vertexBuffer = new DynamicVertexBuffer(memBlock, PosColorTexture.Layout);
}
public void AppendText(char[] text, int startIndex, int count, TextFormat format) {
fixed(char *ptr = text)
AppendText(ptr + startIndex, count, format);
}
public void AppendText(char *text, int count, TextFormat format)
{
// look up the cache entry for the given font and size
CachedFace cachedFace;
var font = format.Font;
var size = FontFace.ComputePixelSize(format.Size, Dpi);
var key = new CacheKey(font.Id, size);
if (!cache.TryGetValue(key, out cachedFace))
{
cache.Add(key, cachedFace = new CachedFace(font, size));
}
// process each character in the string
var nextBreak = BreakCategory.None;
var previous = new CodePoint();
char *end = text + count;
while (text != end)
{
// handle surrogate pairs properly
CodePoint codePoint;
char c = *text++;
if (char.IsSurrogate(c) && text != end)
{
codePoint = new CodePoint(c, *text++);
}
else
{
codePoint = c;
}
// ignore linefeeds directly after a carriage return
if (c == '\n' && (char)previous == '\r')
{
continue;
}
// get the glyph data
CachedGlyph glyph;
if (!cachedFace.Glyphs.TryGetValue(codePoint, out glyph) && !char.IsControl(c))
{
var data = font.GetGlyph(codePoint, size);
var width = data.RenderWidth;
var height = data.RenderHeight;
if (width > atlas.Width || height > atlas.Height)
{
throw new InvalidOperationException("Glyph is larger than the size of the provided atlas.");
}
var rect = new Rect();
if (width > 0 && height > 0)
{
// render the glyph
var memSize = width * height;
var mem = memoryBuffer;
if (mem == null)
{
memoryBuffer = mem = new MemoryBuffer(memSize);
}
mem.Clear(memSize);
data.RenderTo(new Surface {
Bits = mem.Pointer,
Width = width,
Height = height,
Pitch = width
});
// save the rasterized glyph in the user's atlas
rect = packer.Insert(width, height);
if (rect.Height == 0)
{
// didn't fit in the atlas... start a new sheet
currentPage++;
packer.Clear(atlas.Width, atlas.Height);
rect = packer.Insert(width, height);
if (rect.Height == 0)
{
throw new InvalidOperationException("Failed to insert glyph into fresh page.");
}
}
atlas.Insert(currentPage, rect.X, rect.Y, rect.Width, rect.Height, mem.Pointer);
}
glyph = new CachedGlyph(rect, data.HorizontalMetrics.Bearing, data.HorizontalMetrics.Advance);
cachedFace.Glyphs.Add(codePoint, glyph);
}
// check for a kerning offset
var kerning = font.GetKerning(previous, codePoint, size);
previous = codePoint;
// figure out whether this character can serve as a line break point
// TODO: more robust character class handling
var breakCategory = BreakCategory.None;
if (char.IsWhiteSpace(c))
{
if (c == '\r' || c == '\n')
{
breakCategory = BreakCategory.Mandatory;
}
else
{
breakCategory = BreakCategory.Opportunity;
}
}
// the previous character might make us think that this one should be a break opportunity
if (nextBreak > breakCategory)
{
breakCategory = nextBreak;
}
if (c == '-')
{
nextBreak = BreakCategory.Opportunity;
}
// alright, we have all the right glyph data cached and loaded
// append relevant info to our buffer; we'll do the actual layout later
buffer.Add(new BufferEntry {
GlyphData = glyph,
Kerning = kerning,
Break = breakCategory
});
}
}
public void AppendText(string text, TextFormat format) => AppendText(text, 0, text.Length, format);
