diff options
Diffstat (limited to 'fpdf.go')
| -rw-r--r-- | fpdf.go | 164 |
1 files changed, 105 insertions, 59 deletions
@@ -907,7 +907,7 @@ func (f *Fpdf) Circle(x, y, r float64, styleStr string) { // // See tutorial 11 for an example of this function. func (f *Fpdf) Ellipse(x, y, rx, ry, degRotate float64, styleStr string) { - f.Arc(x, y, rx, ry, degRotate, 0, 360, styleStr) + f.arc(x, y, rx, ry, degRotate, 0, 360, styleStr, false) } // Polygon draws a closed figure defined by a series of vertices specified by @@ -1047,54 +1047,7 @@ func (f *Fpdf) CurveBezierCubic(x0, y0, cx0, cy0, cx1, cy1, x1, y1 float64, styl // // See tutorial 11 for an example of this function. func (f *Fpdf) Arc(x, y, rx, ry, degRotate, degStart, degEnd float64, styleStr string) { - x *= f.k - y = (f.h - y) * f.k - rx *= f.k - ry *= f.k - segments := int(degEnd-degStart) / 60 - if segments < 2 { - segments = 2 - } - angleStart := degStart * math.Pi / 180 - angleEnd := degEnd * math.Pi / 180 - angleTotal := angleEnd - angleStart - dt := angleTotal / float64(segments) - dtm := dt / 3 - if degRotate != 0 { - a := -degRotate * math.Pi / 180 - f.outf("q %.5f %.5f %.5f %.5f %.5f %.5f cm", math.Cos(a), -1*math.Sin(a), - math.Sin(a), math.Cos(a), x, y) - x = 0 - y = 0 - } - t := angleStart - a0 := x + rx*math.Cos(t) - b0 := y + ry*math.Sin(t) - c0 := -rx * math.Sin(t) - d0 := ry * math.Cos(t) - f.point(a0/f.k, f.h-(b0/f.k)) - for j := 1; j <= segments; j++ { - // Draw this bit of the total curve - t = (float64(j) * dt) + angleStart - a1 := x + rx*math.Cos(t) - b1 := y + ry*math.Sin(t) - c1 := -rx * math.Sin(t) - d1 := ry * math.Cos(t) - f.curve((a0+(c0*dtm))/f.k, - f.h-((b0+(d0*dtm))/f.k), - (a1-(c1*dtm))/f.k, - f.h-((b1-(d1*dtm))/f.k), - a1/f.k, - f.h-(b1/f.k)) - a0 = a1 - b0 = b1 - c0 = c1 - d0 = d1 - } - f.out(fillDrawOp(styleStr)) - if degRotate != 0 { - f.out("Q") - } + f.arc(x, y, rx, ry, degRotate, degStart, degEnd, styleStr, false) } // SetAlpha sets the alpha blending channel. The blending effect applies to @@ -3487,19 +3440,22 @@ func (f *Fpdf) enddoc() { } // 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. +// 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. +// +// Create a "path" by moving a virtual stylus around the page (with +// MoveTo, LineTo, CurveTo, CurveBezierCubicTo, ArcTo & ClosePath) +// then draw it or fill it in (with DrawPath). 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. // // See tutorial 30 for an example of this function. func (f *Fpdf) MoveTo(x, y float64) { - f.point(x, y) // rename? + f.point(x, y) + f.x, f.y = x, y } // LineTo creates a line from the current stylus location to (x, y), which @@ -3509,6 +3465,7 @@ func (f *Fpdf) MoveTo(x, y float64) { // See tutorial 30 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) + f.x, f.y = x, y } // CurveTo creates a single-segment quadratic Bézier curve. The curve starts at @@ -3521,6 +3478,7 @@ func (f *Fpdf) LineTo(x, y float64) { // See tutorial 30 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) + f.x, f.y = x, y } // CurveBezierCubicTo creates a single-segment cubic Bézier curve. The curve @@ -3533,7 +3491,8 @@ func (f *Fpdf) CurveTo(cx, cy, x, y float64) { // // See tutorial 30 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? + f.curve(cx0, cy0, cx1, cy1, x, y) + f.x, f.y = x, y } // ClosePath creates a line from the current location to the last MoveTo point @@ -3556,3 +3515,90 @@ func (f *Fpdf) ClosePath() { func (f *Fpdf) DrawPath(styleStr string) { f.outf(fillDrawOp(styleStr)) } + +// ArcTo draws an elliptical arc centered at point (x, y). rx and ry specify its +// horizontal and vertical radii. If the start of the arc is not at +// the current position, a connecting line will be drawn. +// +// degRotate specifies the angle that the arc will be rotated. degStart and +// degEnd specify the starting and ending angle of the arc. All angles are +// specified in degrees and measured counter-clockwise from the 3 o'clock +// position. +// +// 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 arc's +// path. Filling uses the current fill color. +// +// See tutorial 30 for an example of this function. +func (f *Fpdf) ArcTo(x, y, rx, ry, degRotate, degStart, degEnd float64) { + f.arc(x, y, rx, ry, degRotate, degStart, degEnd, "", true) +} + +func (f *Fpdf) arc(x, y, rx, ry, degRotate, degStart, degEnd float64, + styleStr string, path bool) { + x *= f.k + y = (f.h - y) * f.k + rx *= f.k + ry *= f.k + segments := int(degEnd-degStart) / 60 + if segments < 2 { + segments = 2 + } + angleStart := degStart * math.Pi / 180 + angleEnd := degEnd * math.Pi / 180 + angleTotal := angleEnd - angleStart + dt := angleTotal / float64(segments) + dtm := dt / 3 + if degRotate != 0 { + a := -degRotate * math.Pi / 180 + f.outf("q %.5f %.5f %.5f %.5f %.5f %.5f cm", + math.Cos(a), -1*math.Sin(a), + math.Sin(a), math.Cos(a), x, y) + x = 0 + y = 0 + } + t := angleStart + a0 := x + rx*math.Cos(t) + b0 := y + ry*math.Sin(t) + c0 := -rx * math.Sin(t) + d0 := ry * math.Cos(t) + sx := a0 / f.k // start point of arc + sy := f.h - (b0 / f.k) + if path { + if f.x != sx || f.y != sy { + // Draw connecting line to start point + f.LineTo(sx, sy) + } + } else { + f.point(sx, sy) + } + for j := 1; j <= segments; j++ { + // Draw this bit of the total curve + t = (float64(j) * dt) + angleStart + a1 := x + rx*math.Cos(t) + b1 := y + ry*math.Sin(t) + c1 := -rx * math.Sin(t) + d1 := ry * math.Cos(t) + f.curve((a0+(c0*dtm))/f.k, + f.h-((b0+(d0*dtm))/f.k), + (a1-(c1*dtm))/f.k, + f.h-((b1-(d1*dtm))/f.k), + a1/f.k, + f.h-(b1/f.k)) + a0 = a1 + b0 = b1 + c0 = c1 + d0 = d1 + if path { + f.x = a1 / f.k + f.y = f.h - (b1 / f.k) + } + } + if !path { + f.out(fillDrawOp(styleStr)) + } + if degRotate != 0 { + f.out("Q") + } +} |