diff options
| -rw-r--r-- | fpdf.go | 70 | ||||
| -rw-r--r-- | fpdf_test.go | 18 |
2 files changed, 88 insertions, 0 deletions
@@ -3383,3 +3383,73 @@ func (f *Fpdf) enddoc() { f.state = 3 return } + +// Path Drawing +// Create a "path" by moving a virtual stylus around the page, then draw it or +// fill it in. The main advantage of using the path drawing routines rather +// than multiple Fpdf.Line is that PDF creates nice line joins at the angles, +// rather than just overlaying the lines. +// +// MoveTo moves the stylus to (x, y) without drawing the path from the +// previous point. Paths must start with a MoveTo to set the original stylus +// location or the result is undefined. +// +// See tutorial 29 for an example of this function. +func (f *Fpdf) MoveTo(x, y float64) { + f.point(x, y) // rename? +} + +// LineTo creates a line from the current stylus location to (x, y), which +// becomes the new stylus location. Note that this only creates the line in +// the path; it does not actually draw the line on the page. +// +// See tutorial 29 for an example of this function. +func (f *Fpdf) LineTo(x, y float64) { + f.outf("%.2f %.2f l", x*f.k, (f.h-y)*f.k) +} + +// CurveTo creates a single-segment quadratic Bézier curve. The curve starts at +// the current stylus location and ends at the point (x, y). The control point +// (cx, cy) specifies the curvature. At the start point, the curve is tangent +// to the straight line between the current stylus location and the control +// point. At the end point, the curve is tangent to the straight line between +// the end point and the control point. +// +// See tutorial 29 for an example of this function. +func (f *Fpdf) CurveTo(cx, cy, x, y float64) { + f.outf("%.5f %.5f %.5f %.5f v", cx*f.k, (f.h-cy)*f.k, x*f.k, (f.h-y)*f.k) +} + +// CurveBezierCubicTo creates a single-segment cubic Bézier curve. The curve +// starts at the current stylus location and ends at the point (x, y). The +// control points (cx0, cy0) and (cx1, cy1) specify the curvature. At the +// current stylus, the curve is tangent to the straight line between the +// current stylus location and the control point (cx0, cy0). At the end point, +// the curve is tangent to the straight line between the end point and the +// control point (cx1, cy1). +// +// See tutorial 29 for examples of this function. +func (f *Fpdf) CurveBezierCubicTo(cx0, cy0, cx1, cy1, x, y float64) { + f.curve(cx0, cy0, cx1, cy1, x, y) // rename? +} + +// ClosePath creates a line from the current location to the last MoveTo point +// (if not the same) and mark the path as closed so the first and last lines +// join nicely. +// +// See tutorial 29 for an example of this function. +func (f *Fpdf) ClosePath() { + f.outf("h") +} + +// DrawPath actually draws the path on the page. +// +// styleStr can be "F" for filled, "D" for outlined only, or "DF" or "FD" for +// outlined and filled. An empty string will be replaced with "D". Drawing uses +// the current draw color, line width, and cap style centered on the +// path. Filling uses the current fill color. +// +// See tutorial 29 for an example of this function. +func (f *Fpdf) DrawPath(styleStr string) { + f.outf(fillDrawOp(styleStr)) +} diff --git a/fpdf_test.go b/fpdf_test.go index f8df0c3..a99fd2d 100644 --- a/fpdf_test.go +++ b/fpdf_test.go @@ -1425,3 +1425,21 @@ func ExampleFpdf_tutorial28() { // Successfully generated pdf/tutorial28.pdf } + +// This example demonstrates the Path Drawing functions, such as: +// MoveTo, LineTo, CurveTo, ..., ClosePath and DrawPath. +func ExampleFpdf_tutorial29() { + pdf := gofpdf.New("P", "mm", "A4", "") + pdf.AddPage() + pdf.MoveTo(20, 20) + pdf.LineTo(190, 20) + pdf.CurveTo(190, 100, 105, 100) + pdf.CurveBezierCubicTo(20, 100, 105, 200, 20, 200) + pdf.ClosePath() + pdf.SetFillColor(200, 200, 200) + pdf.SetLineWidth(3) + pdf.DrawPath("DF") + pdf.OutputAndClose(docWriter(pdf, 29)) + // Output: + // Successfully generated pdf/tutorial29.pdf +} |