One of the key concepts of the PDF imaging model is a path which, in itself, an invisible contour without any markings on the page. Paths must be acted upon by path-painting operators to produce markings. A path may be stroked with a certain color and width, producing an actual curve on the page. A path may also be filled with a color. It may also be used to define a clipping path. Functions in this section are used to construct paths that are subsequently used to provide various effects.
Use Arc to create an elliptically curved path. The arc traverses the perimeter of an PBXEllipse which is bounded by the points ( x1, y1 ) and ( x2, y2 ). The drawn arc is following the perimeter of the ellipse , counterclockwise, from the starting point to the ending point. The starting point is defined by the intersection of the ellipse and a line is defined by the center of the ellipse and ( x3, y3). The ending point is defined by the intersection of the ellipse and a line is defined by the center of the ellipse and... more
Use Arc to create an elliptically curved path. The arc traverses the perimeter of an ellipse which is bounded by the points ( x1, y1 ) and ( x2, y2 ). The drawn arc is following the perimeter of the ellipse, counterclockwise, from the starting point to the ending point. The starting point is defined by the intersection of the ellipse and a line is defined by BegAngle and EndAngle, specified in degrees.
This procedure creates an ellipse path specified by top left point at pixel coordinates ( x1, y1 ) and the bottom right point at ( x2, y2 ) in the counter-clock-wise direction.
Use Pie to append a pie-shaped wedge on the path. The wedge is defined by the ellipse bounded by the rectangle determined by the points ( x1, y1 ) and ( x2, y2). The drawn section is determined by two lines radiating from the center of the ellipse through the points ( x3, y3 ) and ( x4, y4 )
Use Pie to append a pie-shaped wedge on the path. The wedge is defined by the ellipse bounded by the rectangle determined by the points ( x1, y1 ) and ( x2, y2). The drawn section is determined by two lines ( BegAngle and EndAngle, specified in degrees).
This procedure adds a Bezier cubic curve segment to the path starting at the current point as ( x0, y0 ), using two points ( x1, y1 ) and ( x2, y2 ) as control points, and terminating at point ( x3, y3 ). The new current point will be ( x3, y3 ). If there is no current point, an error will result.
Adds a rectangle with rounded corners to path. The rectangle will have edges defined by the points ( x1, y1 ), ( x2, y1 ), ( x2, y2 ), ( x1, y2 ), but the corners will be shaved to create a rounded appearance. The curve of the rounded corners matches the curvature of an ellipse with width x3 and height y3
This closes a path by connecting the first and the last point in the path currently constructed. Calling of this procedure is often needed to avoid a notch in a stroked path, and to make "line join" work correctly in joining the first and the last points.