public static void Read(this IGlyphTranslator tx, GlyphPointF[] glyphPoints, ushort[] contourEndPoints, float scale = 1)
{
int startContour = 0;
int cpoint_index = 0;//current point index
int todoContourCount = contourEndPoints.Length;
//-----------------------------------
//1. start read data from a glyph
tx.BeginRead(todoContourCount);
//-----------------------------------
float latest_moveto_x = 0;
float latest_moveto_y = 0;
int curveControlPointCount = 0; // 1 curve control point => Quadratic, 2 curve control points => Cubic
while (todoContourCount > 0)
{
//foreach contour...
//next contour will begin at...
int nextCntBeginAtIndex = contourEndPoints[startContour] + 1;
//reset ...
Vector2 c1 = new Vector2();
Vector2 c2 = new Vector2();
bool curveMode = false;
bool isFirstPoint = true; //first point of this contour
///for each point in this contour
for (; cpoint_index < nextCntBeginAtIndex; ++cpoint_index)
{
GlyphPointF p = glyphPoints[cpoint_index];
float p_x = p.X * scale;
float p_y = p.Y * scale;
//int vtag = (int)flags[cpoint_index] & 0x1;
//bool has_dropout = (((vtag >> 2) & 0x1) != 0);
//int dropoutMode = vtag >> 3;
if (p.onCurve)
{
//point p is an on-curve point (on outline). (not curve control point)
//possible ways..
//1. if we are in curve mode, then p is end point
// we must decide which curve to create (Curve3 or Curve4)
// easy, ...
// if curveControlPointCount == 1 , then create Curve3
// else curveControlPointCount ==2 , then create Curve4
//2. if we are NOT in curve mode,
// if p is first point then set this to x0,y0
// else then p is end point of a line.
if (curveMode)
{
switch (curveControlPointCount)
{
case 1:
{
tx.Curve3(
c1.X, c1.Y,
p_x, p_y);
}
break;
case 2:
{
//for TrueType font
//we should not be here?
tx.Curve4(
c1.X, c1.Y,
c2.X, c2.Y,
p_x, p_y);
}
break;
default:
{
throw new NotSupportedException();
}
}
//reset curve control point count
curveControlPointCount = 0;
//exist from curve mode
curveMode = false;
}
else
{
//as describe above,...
if (isFirstPoint)
{
isFirstPoint = false;
tx.MoveTo(latest_moveto_x = (p_x), latest_moveto_y = (p_y));
}
else
{
tx.LineTo(p_x, p_y);
}
//if (has_dropout)
//{
// //printf("[%d] on,dropoutMode=%d: %d,y:%d \n", mm, dropoutMode, vpoint.x, vpoint.y);
//}
//else
//{
// //printf("[%d] on,x: %d,y:%d \n", mm, vpoint.x, vpoint.y);
//}
}
}
else
{
//this point is curve control point***
//so set curve mode = true
curveMode = true;
//check number if existing curve control
switch (curveControlPointCount)
{
case 0:
c1 = new Vector2(p_x, p_y);
//this point may be part 1st control point of a curve,
//store it and wait for next point before make decision ***
break;
case 1:
//we already have previous 1st control point (c1)
//-------------------------------------
//please note that TrueType font
//compose of Quadractic Bezier Curve (Curve3) ***
//-------------------------------------
//in this case, this is NOT Cubic,
//this is 2 CONNECTED Quadractic Bezier Curves***
//
//we must create 'end point' of the first curve
//and set it as 'begin point of the second curve.
//
//this is done by ...
//1. calculate mid point between c1 and the latest point (p_x,p_y)
Vector2 mid = GetMid(c1, p_x, p_y);
//----------
//2. generate curve3 ***
tx.Curve3(
c1.X, c1.Y,
mid.X, mid.Y);
//------------------------
//3. so curve control point number is reduce by 1***
curveControlPointCount--;
//------------------------
//4. and set (p_x,p_y) as 1st control point for the new curve
c1 = new Vector2(p_x, p_y);
//
//printf("[%d] bzc2nd, x: %d,y:%d \n", mm, vpoint.x, vpoint.y);
break;
default:
throw new NotSupportedException();
}
//count
curveControlPointCount++;
}
}
//--------
//when finish,
//ensure that the contour is closed.
if (curveMode)
{
switch (curveControlPointCount)
{
case 0: break;
case 1:
{
tx.Curve3(c1.X, c1.Y,
latest_moveto_x, latest_moveto_y);
}
break;
case 2:
{
//for TrueType font
//we should not be here?
tx.Curve4(c1.X, c1.Y,
c2.X, c2.Y,
latest_moveto_x, latest_moveto_y);
}
break;
default:
{ throw new NotSupportedException(); }
}
//reset
curveMode = false;
curveControlPointCount = 0;
}
//--------
tx.CloseContour(); //***
startContour++;
todoContourCount--;
//--------
}
//finish
tx.EndRead();
}
public void Curve4(float x1, float y1, float x2, float y2, float x3, float y3)
{
_is_contour_opened = true;
_tx.Curve4(x1 * _scale, y1 * _scale, x2 * _scale, y2 * _scale, x3 * _scale, y3 * _scale);
}
public void RR_CurveTo()
{
//|- {dxa dya dxb dyb dxc dyc}+ rrcurveto (8) |-
//appends a Bézier curve, defined by dy1 to the current point.
//With dxa...dyc, to the current point.
//For each subsequent set of six arguments, an additional
//curve is appended to the current point.
//The number of curve segments is determined from
//the number of arguments on the number stack and
//is limited only by the size of the number stack
//All Bézier curve path segments are drawn using six arguments,
//dxa, dya, dxb, dyb, dxc, dyc; where dxa and dya are relative to
//the current point, and all subsequent arguments are relative to
//the previous point.A number of the curve operators take
//advantage of the situation where some tangent points are
//horizontal or vertical(and hence the value is zero), thus
//reducing the number of arguments needed.
int i = 0;
#if DEBUG
if ((_currentIndex % 6) != 0)
{
// i++;
}
#endif
double curX = _currentX;
double curY = _currentY;
for (; i < _currentIndex;)
{
_glyphTranslator.Curve4(
(float)(curX += _argStack[i + 0]), (float)(curY += _argStack[i + 1]), //dxa,dya
(float)(curX += _argStack[i + 2]), (float)(curY += _argStack[i + 3]), //dxb,dyb
(float)(curX += _argStack[i + 4]), (float)(curY += _argStack[i + 5]) //dxc,dyc
);
//
i += 6;
}
_currentX = curX;
_currentY = curY;
_currentIndex = 0; //clear stack
}
