public ActiveEdge(GlyphEdge e, int offsetX, float start)
{
float dxDy = (e.X1 - e.X) / (e.Y1 - e.Y);
Fdx = dxDy;
Fdy = dxDy != 0.0f ? 1.0f / dxDy : 0.0f;
Fx = e.X + dxDy * (start - e.Y);
Fx -= offsetX;
Direction = e.Invert ? 1.0f : -1.0f;
Sy = e.Y;
Ey = e.Y1;
}
public static void RenderGlyph(GlyphCanvas canvas, Glyph glyph, float scale, bool invertY = true)
{
if (scale == 0f)
{
return;
}
if (canvas.Width == 0 || canvas.Height == 0)
{
return;
}
GlyphVertex[] vertices = glyph.Vertices;
var flatnessInPixels = 0.35f;
Vector2[] windings = FlattenCurves(vertices, flatnessInPixels / scale, out int[] contourLengths);
if (windings == null)
{
return;
}
float scaleX = scale;
float scaleY = scale;
if (invertY)
{
scaleY = -scaleY;
}
int n = contourLengths.Sum();
var e = new GlyphEdge[n + 1];
n = 0;
var wOffset = 0;
var subSample = 1;
for (var i = 0; i < contourLengths.Length; i++)
{
int j = contourLengths[i] - 1;
for (var k = 0; k < contourLengths[i]; j = k++)
{
int a = k;
int b = j;
if (windings[wOffset + j].Y == windings[wOffset + k].Y)
{
continue;
}
e[n].Invert = false;
if (invertY && windings[wOffset + j].Y > windings[wOffset + k].Y || !invertY && windings[wOffset + j].Y < windings[wOffset + k].Y)
{
e[n].Invert = true;
a = j;
b = k;
}
e[n].X = windings[wOffset + a].X * scaleX;
e[n].Y = windings[wOffset + a].Y * scaleY * subSample;
e[n].X1 = windings[wOffset + b].X * scaleX;
e[n].Y1 = windings[wOffset + b].Y * scaleY * subSample;
n++;
}
wOffset += contourLengths[i];
}
Array.Resize(ref e, n + 1); // todo
QuickSortEdges(new Span <GlyphEdge>(e), n);
// Insert Sort
for (var i = 1; i < n; i++)
{
GlyphEdge t = e[i];
int j = i;
while (j > 0)
{
ref GlyphEdge b = ref e[j - 1];
if (!(t.Y < b.Y))
{
break;
}
e[j] = e[j - 1];
j--;
}
if (i != j)
{
e[j] = t;
}
}
