331 lines
9.1 KiB
Go
331 lines
9.1 KiB
Go
package logic
|
|
|
|
import (
|
|
"bytes"
|
|
"math"
|
|
"regexp"
|
|
"strconv"
|
|
|
|
"github.com/signintech/gopdf"
|
|
)
|
|
|
|
var embeddedFont []byte
|
|
|
|
func SetFontData(data []byte) {
|
|
embeddedFont = data
|
|
}
|
|
|
|
// GeneratePDF 生成 PDF 字节流
|
|
func GeneratePDF(chars []HanziData, mode, paperSize string, flipY bool) ([]byte, error) {
|
|
pdf := &gopdf.GoPdf{}
|
|
|
|
rect := gopdf.Rect{W: 595.28, H: 841.89} // A4 default
|
|
if paperSize == "Letter" {
|
|
rect = gopdf.Rect{W: 612, H: 792}
|
|
}
|
|
pdf.Start(gopdf.Config{PageSize: rect})
|
|
|
|
if len(embeddedFont) > 0 {
|
|
_ = pdf.AddTTFFontData("font", embeddedFont)
|
|
}
|
|
|
|
if mode == "step" {
|
|
addStepPages(pdf, chars, flipY, rect.W, rect.H)
|
|
} else {
|
|
addTeachingPages(pdf, chars, flipY, rect.W, rect.H)
|
|
}
|
|
|
|
var buf bytes.Buffer
|
|
_, err := pdf.WriteTo(&buf)
|
|
return buf.Bytes(), err
|
|
}
|
|
|
|
func addTeachingPages(pdf *gopdf.GoPdf, chars []HanziData, flipY bool, pW, pH float64) {
|
|
cols, rows := 2, 3
|
|
gap := 17.0
|
|
margin := 40.0
|
|
|
|
cellW := (pW - 2*margin - float64(cols-1)*gap) / float64(cols)
|
|
cellH := (pH - 2*margin - float64(rows-1)*gap) / float64(rows)
|
|
size := math.Min(cellW, cellH)
|
|
|
|
totalW := float64(cols)*size + float64(cols-1)*gap
|
|
totalH := float64(rows)*size + float64(rows-1)*gap
|
|
marginX := (pW - totalW) / 2
|
|
marginY := (pH - totalH) / 2
|
|
|
|
for i := 0; i < len(chars); i += 6 {
|
|
pdf.AddPage()
|
|
end := i + 6
|
|
if end > len(chars) {
|
|
end = len(chars)
|
|
}
|
|
batch := chars[i:end]
|
|
|
|
for idx, data := range batch {
|
|
c, r := idx%cols, idx/cols
|
|
x := marginX + float64(c)*(size+gap)
|
|
y := marginY + float64(r)*(size+gap)
|
|
drawCharacter(pdf, data, x, y, size, flipY, len(data.Strokes), true)
|
|
}
|
|
}
|
|
}
|
|
|
|
func addStepPages(pdf *gopdf.GoPdf, chars []HanziData, flipY bool, pW, pH float64) {
|
|
cols := 9
|
|
margin := 30.0
|
|
size := (pW - 2*margin) / float64(cols)
|
|
|
|
pdf.AddPage()
|
|
currY := margin
|
|
|
|
for _, data := range chars {
|
|
numStrokes := len(data.Strokes)
|
|
rowsNeeded := 1
|
|
if numStrokes > 8 {
|
|
rowsNeeded = 1 + (numStrokes - 8 + 7) / 8
|
|
}
|
|
|
|
if currY + float64(rowsNeeded)*size > pH - margin {
|
|
pdf.AddPage()
|
|
currY = margin
|
|
}
|
|
|
|
totalGridsInRows := rowsNeeded * cols
|
|
strokeCounter := 0
|
|
|
|
for gridIdx := 0; gridIdx < totalGridsInRows; gridIdx++ {
|
|
rowInChar := gridIdx / cols
|
|
colInChar := gridIdx % cols
|
|
x := margin + float64(colInChar)*size
|
|
y := currY + float64(rowInChar)*size
|
|
|
|
if rowInChar == 0 && colInChar == 0 {
|
|
drawCharacter(pdf, data, x, y, size, flipY, len(data.Strokes), false)
|
|
strokeCounter = 1
|
|
} else if rowInChar > 0 && colInChar == 0 {
|
|
drawMiZiGe(pdf, x, y, size)
|
|
} else if strokeCounter <= numStrokes {
|
|
drawStepBox(pdf, data, x, y, size, flipY, strokeCounter)
|
|
strokeCounter++
|
|
} else {
|
|
drawMiZiGe(pdf, x, y, size)
|
|
}
|
|
}
|
|
currY += float64(rowsNeeded) * size
|
|
}
|
|
}
|
|
|
|
func drawStepBox(pdf *gopdf.GoPdf, data HanziData, x, y, size float64, flipY bool, strokeLimit int) {
|
|
drawMiZiGe(pdf, x, y, size)
|
|
padding := size * 0.12
|
|
drawSize := size - 2*padding
|
|
scale := drawSize / 1024.0
|
|
offsetX := x + padding
|
|
offsetY := y + padding
|
|
|
|
pdf.SetFillColor(180, 180, 180)
|
|
for i := 0; i < strokeLimit; i++ {
|
|
points := parseSVGPath(data.Strokes[i], scale, offsetX, offsetY, flipY)
|
|
if len(points) > 2 {
|
|
pdf.Polygon(points, "F")
|
|
}
|
|
}
|
|
}
|
|
|
|
func drawCharacter(pdf *gopdf.GoPdf, data HanziData, x, y, size float64, flipY bool, strokeLimit int, showAnnotations bool) {
|
|
if showAnnotations {
|
|
drawGrid(pdf, x, y, size)
|
|
} else {
|
|
drawMiZiGe(pdf, x, y, size)
|
|
}
|
|
|
|
padding := size * 0.12
|
|
drawSize := size - 2*padding
|
|
scale := drawSize / 1024.0
|
|
offsetX := x + padding
|
|
offsetY := y + padding
|
|
|
|
isFull := strokeLimit == len(data.Strokes)
|
|
if isFull {
|
|
if showAnnotations {
|
|
pdf.SetFillColor(240, 240, 240)
|
|
} else {
|
|
pdf.SetFillColor(0, 0, 0)
|
|
}
|
|
} else {
|
|
pdf.SetFillColor(180, 180, 180)
|
|
}
|
|
|
|
for sIdx := 0; sIdx < len(data.Strokes); sIdx++ {
|
|
if sIdx >= strokeLimit && !isFull {
|
|
break
|
|
}
|
|
points := parseSVGPath(data.Strokes[sIdx], scale, offsetX, offsetY, flipY)
|
|
if len(points) > 2 {
|
|
pdf.Polygon(points, "F")
|
|
}
|
|
}
|
|
|
|
if showAnnotations && isFull {
|
|
fontSize := size * 0.035
|
|
if len(embeddedFont) > 0 {
|
|
_ = pdf.SetFont("font", "", fontSize)
|
|
}
|
|
for idx, median := range data.Medians {
|
|
mPoints := transformPoints(median, scale, offsetX, offsetY, flipY)
|
|
if len(mPoints) < 2 { continue }
|
|
|
|
pdf.SetStrokeColor(255, 0, 0)
|
|
pdf.SetLineWidth(0.6)
|
|
for j := 0; j < len(mPoints)-1; j++ {
|
|
pdf.Line(mPoints[j].X, mPoints[j].Y, mPoints[j+1].X, mPoints[j+1].Y)
|
|
}
|
|
|
|
pdf.SetFillColor(255, 0, 0)
|
|
drawArrow(pdf, mPoints[len(mPoints)-1], mPoints[len(mPoints)-2], size * 0.035)
|
|
|
|
startP, nextP := mPoints[0], mPoints[1]
|
|
r := size * 0.025
|
|
dx, dy := nextP.X-startP.X, nextP.Y-startP.Y
|
|
dist := math.Sqrt(dx*dx + dy*dy)
|
|
ux, uy := -1.0, -1.0
|
|
if dist > 0.001 { ux, uy = dx/dist, dy/dist }
|
|
centerX, centerY := startP.X - ux*r, startP.Y - uy*r
|
|
|
|
pdf.SetStrokeColor(255, 0, 0)
|
|
pdf.SetLineWidth(0.5)
|
|
pdf.Oval(centerX - r, centerY - r, centerX + r, centerY + r)
|
|
|
|
if len(embeddedFont) > 0 {
|
|
numStr := strconv.Itoa(idx+1)
|
|
tw := fontSize * 0.6 * float64(len(numStr)) / 2
|
|
if len(numStr) > 1 { tw = fontSize * 0.5 }
|
|
pdf.SetFillColor(255, 0, 0)
|
|
pdf.SetXY(centerX - tw/2, centerY - fontSize/2)
|
|
_ = pdf.Cell(nil, numStr)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func drawGrid(pdf *gopdf.GoPdf, x, y, size float64) {
|
|
pdf.SetStrokeColor(220, 220, 220)
|
|
pdf.SetLineWidth(0.4)
|
|
pdf.RectFromUpperLeft(x, y, size, size)
|
|
mid := size / 2
|
|
drawDashedLine(pdf, x, y+mid, x+size, y+mid)
|
|
drawDashedLine(pdf, x+mid, y, x+mid, y+size)
|
|
}
|
|
|
|
func drawMiZiGe(pdf *gopdf.GoPdf, x, y, size float64) {
|
|
pdf.SetStrokeColor(220, 220, 220)
|
|
pdf.SetLineWidth(0.4)
|
|
pdf.RectFromUpperLeft(x, y, size, size)
|
|
mid := size / 2
|
|
drawDashedLine(pdf, x, y+mid, x+size, y+mid)
|
|
drawDashedLine(pdf, x+mid, y, x+mid, y+size)
|
|
drawDashedLine(pdf, x, y, x+size, y+size)
|
|
drawDashedLine(pdf, x, y+size, x+size, y)
|
|
}
|
|
|
|
func drawDashedLine(pdf *gopdf.GoPdf, x1, y1, x2, y2 float64) {
|
|
dashLen := 2.0
|
|
dx, dy := x2-x1, y2-y1
|
|
dist := math.Sqrt(dx*dx + dy*dy)
|
|
if dist < 0.001 { return }
|
|
ux, uy := dx/dist, dy/dist
|
|
for i := 0.0; i < dist; i += dashLen * 2 {
|
|
end := i + dashLen
|
|
if end > dist { end = dist }
|
|
pdf.Line(x1+ux*i, y1+uy*i, x1+ux*end, y1+uy*end)
|
|
}
|
|
}
|
|
|
|
func drawArrow(pdf *gopdf.GoPdf, target, prev gopdf.Point, length float64) {
|
|
angle := math.Atan2(target.Y-prev.Y, target.X-prev.X)
|
|
arrowAngle := math.Pi / 6
|
|
p1X := target.X + length*math.Cos(angle+math.Pi+arrowAngle)
|
|
p1Y := target.Y + length*math.Sin(angle+math.Pi+arrowAngle)
|
|
p2X := target.X + length*math.Cos(angle+math.Pi-arrowAngle)
|
|
p2Y := target.Y + length*math.Sin(angle+math.Pi-arrowAngle)
|
|
pdf.Polygon([]gopdf.Point{target, {X: p1X, Y: p1Y}, {X: p2X, Y: p2Y}}, "F")
|
|
}
|
|
|
|
func transformPoints(pts []Point, scale, ox, oy float64, flipY bool) []gopdf.Point {
|
|
res := make([]gopdf.Point, len(pts))
|
|
for i, p := range pts {
|
|
y := p[1]
|
|
if flipY { y = 1024 - y }
|
|
res[i] = gopdf.Point{X: ox + p[0]*scale, Y: oy + y*scale}
|
|
}
|
|
return res
|
|
}
|
|
|
|
var reSVG = regexp.MustCompile(`([MLQCZ])|(-?\d+\.?\d*)`)
|
|
|
|
func parseSVGPath(path string, scale, ox, oy float64, flipY bool) []gopdf.Point {
|
|
var pts []gopdf.Point
|
|
matches := reSVG.FindAllStringSubmatch(path, -1)
|
|
|
|
var lastX, lastY float64
|
|
|
|
for idx := 0; idx < len(matches); {
|
|
item := matches[idx][0]
|
|
if item == "M" || item == "L" {
|
|
if idx+2 < len(matches) {
|
|
x, _ := strconv.ParseFloat(matches[idx+1][0], 64)
|
|
y, _ := strconv.ParseFloat(matches[idx+2][0], 64)
|
|
lastX, lastY = x, y
|
|
if flipY { y = 1024 - y }
|
|
pts = append(pts, gopdf.Point{X: ox + x*scale, Y: oy + y*scale})
|
|
idx += 3
|
|
} else { idx++ }
|
|
} else if item == "C" {
|
|
// Cubic Bezier: C x1 y1 x2 y2 x y
|
|
if idx+6 < len(matches) {
|
|
x1, _ := strconv.ParseFloat(matches[idx+1][0], 64)
|
|
y1, _ := strconv.ParseFloat(matches[idx+2][0], 64)
|
|
x2, _ := strconv.ParseFloat(matches[idx+3][0], 64)
|
|
y2, _ := strconv.ParseFloat(matches[idx+4][0], 64)
|
|
x, _ := strconv.ParseFloat(matches[idx+5][0], 64)
|
|
y, _ := strconv.ParseFloat(matches[idx+6][0], 64)
|
|
|
|
// Sample points along the curve
|
|
for t := 0.2; t <= 1.0; t += 0.2 {
|
|
tx := math.Pow(1-t, 3)*lastX + 3*math.Pow(1-t, 2)*t*x1 + 3*(1-t)*math.Pow(t, 2)*x2 + math.Pow(t, 3)*x
|
|
ty := math.Pow(1-t, 3)*lastY + 3*math.Pow(1-t, 2)*t*y1 + 3*(1-t)*math.Pow(t, 2)*y2 + math.Pow(t, 3)*y
|
|
ty_final := ty
|
|
if flipY { ty_final = 1024 - ty }
|
|
pts = append(pts, gopdf.Point{X: ox + tx*scale, Y: oy + ty_final*scale})
|
|
}
|
|
lastX, lastY = x, y
|
|
idx += 7
|
|
} else { idx++ }
|
|
} else if item == "Q" {
|
|
// Quadratic Bezier: Q x1 y1 x y
|
|
if idx+4 < len(matches) {
|
|
x1, _ := strconv.ParseFloat(matches[idx+1][0], 64)
|
|
y1, _ := strconv.ParseFloat(matches[idx+2][0], 64)
|
|
x, _ := strconv.ParseFloat(matches[idx+3][0], 64)
|
|
y, _ := strconv.ParseFloat(matches[idx+4][0], 64)
|
|
|
|
for t := 0.2; t <= 1.0; t += 0.2 {
|
|
tx := math.Pow(1-t, 2)*lastX + 2*(1-t)*t*x1 + math.Pow(t, 2)*x
|
|
ty := math.Pow(1-t, 2)*lastY + 2*(1-t)*t*y1 + math.Pow(t, 2)*y
|
|
ty_final := ty
|
|
if flipY { ty_final = 1024 - ty }
|
|
pts = append(pts, gopdf.Point{X: ox + tx*scale, Y: oy + ty_final*scale})
|
|
}
|
|
lastX, lastY = x, y
|
|
idx += 5
|
|
} else { idx++ }
|
|
} else if item == "Z" {
|
|
idx++
|
|
} else {
|
|
idx++
|
|
}
|
|
}
|
|
return pts
|
|
}
|