在 Roassal3 中使用多個繪圖時如何在行尾添加水平線標簽

Question

我正在嘗試使用 Pharo 10 中的 Roassal3 來可視化多個系列的數據。 我已經成功地繪制了圖表，但想要標記線條。 我嘗試使用 RSLegend 來顯示帶有相應顏色框（對應於線條顏色）的文本，但它們會顯得太大，最終會縮小圖形以適應畫布。 如果我可以操縱圖例以不同的方式顯示，那將有所幫助，但我記得看到過一個示例，使用的是 Roassal 的早期版本，它在行尾為每一行顯示一個標簽。 這將是理想的，所以我嘗試添加一個 RSLabel 作為繪圖的 markerEnd。 除了標簽都以不同的角度出現（大概是情節線的角度，最后）之外，這很有效。 如何讓結束標記標簽水平顯示？ Roassal3 的文檔仍在進行中，所以我找不到任何示例。

我已經更新了示例代碼，以展示我對結束標記、圖例和裝飾器的嘗試（沒有一個是理想的，但我可以使用裝飾器）：

| chart plot dates values firstDate labels legend offset plotLabel renderedLabel canvasCopy |
chart := RSChart new.
canvasCopy := chart canvas copy.
dates := (20 to: 1 by: -1) collect: [ :i | Date today subtractDays: i ]. 
firstDate := dates first.
offset := 20 @ -50.
values := #(
    #(4.29 4.01 3.82 3.91 4.01 3.73 4.47 4.28 4.18 4.00 3.72 4.27 3.99 4.91 5.09 4.91 5.09 4.91 4.44 4.91)
    #(2.0 1.98 1.98 1.98 1.99 1.96 2.07 1.96 1.90 1.95 1.98 2.04 2.12 2.12 2.21 2.27 2.27 2.10 2.19 1.95)
    ).
labels := #('series 1' 'series 2').
values with: labels do: [ :series :label | 
   plot := RSLinePlot new markerEnd: (RSLabel new text: label).
   plot 
       x: (dates collect: [ :date | date julianDayNumber - firstDate julianDayNumber ])
       y: series.
   chart addPlot: plot.
    plotLabel := RSYLabelDecoration new right; 
        title: '~' , label;
        fontSize: 12;
        rotationAngle: 90;
        color: (chart colorFor: plot);
        offset: offset;
        yourself.
    chart addDecoration: plotLabel.
    renderedLabel := (plotLabel copy renderIn: canvasCopy) label.
    offset := (0 - renderedLabel textWidth) @ (offset y + renderedLabel textHeight + 4). 
 ].
canvasCopy shapes copy do: [ :shape | canvasCopy removeShape: shape ].
chart addDecoration: (RSHorizontalTick new labelConversion: [ :value | 
    Date julianDayNumber: firstDate julianDayNumber + value ]; useDiagonalLabel; yourself).
chart addDecoration: RSVerticalTick new.
chart ylabel: 'The values'.
chart build.
legend := RSLegend new.
legend container: chart canvas.
labels with: chart plots do: [ :c : p |
    legend text: c withBoxColor: (chart colorFor: p) ].
legend layout horizontalCompactTree .
legend build.
^chart canvas open

Answer 1

根據 Alexandre Bergel 的提示，我現在有一種合理的方法可以在情節線的末尾繪制標簽。 出於興趣，我在下面的操場代碼中包含了三種識別情節線的方法，使用情節標簽的結尾，使用右側裝飾和使用更標准的圖例。 它在某些地方很亂，但可以通過將代碼移動到更合適的對象來清理很多。

| chart plot dates values firstDate labels legend offset plotLabel renderedLabel canvasCopy maxOffset |
chart := RSChart new.
canvasCopy := RSCanvas new.
dates := (10 to: 1 by: -1) collect: [ :i | Date today subtractDays: i ]. 
firstDate := dates first.
offset := 20 @ -50.
maxOffset := 0.
values := #(
    #(3.72 4.27 3.99 4.91 5.09 4.91 5.09 4.91 4.44 4.91)
    #(4.29 4.01 3.82 3.91 4.01 3.73 4.47 4.28 4.18 4.00)
    #(1.98 2.04 2.12 2.12 2.21 2.27 2.27 2.10 2.19 1.95)
    #(2.5 2.3 2.7 2.73 2.15 2.6 2.63 2.57 2.4 2.8)
    #(2.0 1.98 1.98 1.98 1.99 1.96 2.07 1.96 1.90 1.95)
    ).
labels := #('first series' 'second series' 'series number 4' 'the third series' 'a fifth series').
values with: labels do: [ :series :label | 
   plot := RSLinePlot new.
   plot 
       x: (dates collect: [ :date | date julianDayNumber - firstDate julianDayNumber ])
       y: series.
   chart addPlot: plot.
    "If adding a legend to the right, RSYLabel decoration is needed but with modified offsets to get them to lay out vertically."
    plotLabel := RSYLabelDecoration new right; 
        title: '~' , label;
        fontSize: 12;
        rotationAngle: 90;
        color: (chart colorFor: plot);
        offset: offset;
        yourself.
    chart addDecoration: plotLabel.
    renderedLabel := (plotLabel renderIn: canvasCopy) label.
    maxOffset := maxOffset max: renderedLabel textWidth.
    offset := (0 - maxOffset) @ (offset y + renderedLabel textHeight + 4).
 ].
canvasCopy := nil.
chart addDecoration: (RSHorizontalTick new labelConversion: [ :value | 
    Date julianDayNumber: firstDate julianDayNumber + value ]; useDiagonalLabel; yourself).
chart addDecoration: RSVerticalTick new.
"When adding labels at the end of the plot lines, the right hand line of the chart box will overlay the labels so alter the
spine to a polygon which only draws the x and y axes. "
spine := chart decorations
        detect: [ :d | d class == RSChartSpineDecoration ].
spine shape: (RSPolygon new points: {(0 @ 0). (0 @ 0). (0 @ (chart extent y)). (chart extent x @ (chart extent y)). (chart extent x @ (chart extent y)). (0 @ (chart extent y)) }; noPaint; withBorder; yourself).
chart ylabel: 'The values'.
chart build.
"To use standard legend under the chart"
legend := RSLegend new defaultLabel: (RSLabel new fontSize: 8; yourself).
legend container: chart canvas.
labels with: chart plots do: [ :c : p |
    legend text: c withShape: (RSPolygon new points: { 0 @ -2. 10 @ -2. 10 @ 2. 0 @ 2 }; color: (chart colorFor: p))
    ].
legend layout grid.
legend build.

rsLabels := Dictionary new: chart plots size.
chart plots with: labels do: [ :plot :label | rsLabels at: plot put: ((RSLabel text: label) fontSize: 5) ].
lastys := chart plots collect: [ :pl | 
    Association key: pl value: (pl yScale scale: pl yValues last) ].
lastys sort: [ :el1 :el2 | 
    el1 value = el2 value 
        "If the last y coordinate is the same for both plots, order by the second last y point (reverse ordering)"
        ifTrue: [ (el1 key yValues at: el1 key yValues size - 1) > (el2 key yValues at: el2 key yValues size - 1) ] 
        ifFalse: [ el1 value < el2 value ] ].
lastys withIndexDo: [ :lasty :index |
        numPlots := lastys size.
        plot := lasty key.
        label := rsLabels at: plot.
        label color: plot color.
        chart canvas add: label.
        yPoint := lasty value.
        textHeight := label textHeight.
        index < numPlots ifTrue: [ 
            "Reset the y point to be about textHeight away from the next one, if they are close"
            (diff := (yPoint - (lastys at: index + 1) value) abs) < textHeight 
                ifTrue: [ yPoint := yPoint - (textHeight / 2) + (diff / 2) ] ].
        index > 1 ifTrue: [ 
            "Reset the y point to be about textHeight away from the last one, if they are close"
            (diff := ((lastys at: index - 1) value - yPoint ) abs) < textHeight 
                ifTrue: [ yPoint := yPoint + (textHeight / 2) - (diff / 2) ] ].
        label translateTo: ((plot xScale scale: plot xValues last) + (label textWidth / 2) + 1) @ yPoint.
    ].
^chart canvas