vba - 如何从 PowerPoint 调色板中获取 RGB/Long 值

Question

我正在尝试(大部分成功)从事件 ThemeColorScheme 中“读取”颜色.

下面的子程序将从主题中获取 12 种颜色，例如这是 myAccent1 :



我还需要从调色板中获得另外 4 种颜色。我需要的四种颜色将是上面指示的颜色正下方的一种，然后是从左到右接下来的 3 种颜色。

因为ThemeColorScheme对象只有 12 个项目我得到 The specified value is out of range错误，正如预期的那样，如果我尝试为 myAccent9 赋值这边走。我了解此错误及其发生原因。我不知道如何从调色板访问其他 40 多种颜色，这些颜色不属于 ThemeColorScheme目的？

Private Sub ColorOverride()

Dim pres As Presentation
Dim thm As OfficeTheme
Dim themeColor As themeColor
Dim schemeColors As ThemeColorScheme

Set pres = ActivePresentation

Set schemeColors = pres.Designs(1).SlideMaster.Theme.ThemeColorScheme

    myDark1 = schemeColors(1).RGB         'msoThemeColorDark1
    myLight1 = schemeColors(2).RGB        'msoThemeColorLight
    myDark2 = schemeColors(3).RGB         'msoThemeColorDark2
    myLight2 = schemeColors(4).RGB        'msoThemeColorLight2
    myAccent1 = schemeColors(5).RGB       'msoThemeColorAccent1
    myAccent2 = schemeColors(6).RGB       'msoThemeColorAccent2
    myAccent3 = schemeColors(7).RGB       'msoThemeColorAccent3
    myAccent4 = schemeColors(8).RGB       'msoThemeColorAccent4
    myAccent5 = schemeColors(9).RGB       'msoThemeColorAccent5
    myAccent6 = schemeColors(10).RGB      'msoThemeColorAccent6
    myAccent7 = schemeColors(11).RGB      'msoThemeColorThemeHyperlink
    myAccent8 = schemeColors(12).RGB      'msoThemeColorFollowedHyperlink

    '## THESE LINES RAISE AN ERROR, AS EXPECTED:

    'myAccent9 = schemeColors(13).RGB     
    'myAccent10 = schemeColors(14).RGB
    'myAccent11 = schemeColors(15).RGB
    'myAccent12 = schemeColors(16).RGB

End Sub

所以我的问题是，如何从调色板/主题中获取这些颜色的 RGB 值？

Answer 1

第一眼Floris' solution似乎可行，但如果您关心准确性，您很快就会意识到先前的解决方案仅与色彩空间的一小部分的办公室颜色计算相匹配。

正确的解决方案 - 使用 HSL 色彩空间

办公室好像用HSL color模式，同时计算着色和阴影，并使用此技术为我们提供了几乎 100% 准确的颜色计算(在 Office 2013 上测试)。

正确计算值的方法似乎是:

将基本 RGB 颜色转换为 HSL

找到用于五种子颜色的色调和阴影值

应用色调/阴影值

从 HSL 转换回 RGB 色彩空间

要找到色调/阴影值(第 3 步)，您可以查看 HSL 颜色的亮度值并使用此表(通过反复试验找到):

| [0.0] | <0.0 - 0.2> | [0.2 - 0.8] | <0.8 - 1.0> | [1.0] |
|:-----:|:-----------:|:-----------:|:-----------:|:-----:|
| + .50 |    + .90    |    + .80    |    - .10    | - .05 |
| + .35 |    + .75    |    + .60    |    - .25    | - .15 |
| + .25 |    + .50    |    + .40    |    - .50    | - .25 |
| + .10 |    + .25    |    - .25    |    - .75    | - .35 |
| + .05 |    + .10    |    - .50    |    - .90    | - .50 |

正值使颜色着色(使其更亮)，负值使颜色着色(使其更暗)。有五个组； 1 组为全黑，1 组为全白。这些将只匹配这些特定值(而不是例如 RGB = {255, 255, _254_} )。然后是两个小范围的非常深和非常浅的颜色，分别处理，最后是所有其余颜色的大范围。

注意:+0.40 的值意味着该值将变亮 40%，而不是原始颜色的 40%(这实际上意味着它变亮 60%)。这可能会让某些人感到困惑，但这是 Office 在内部使用这些值的方式(即在 Excel 中通过 TintAndShade 的 Cell.Interior 属性)。

PowerPoint VBA代码实现解决方案

【免责声明】:我已经建立在 Floris 的解决方案上来创建这个 VBA。很多HSL翻译代码也是从Word article mentioned in the comments复制过来的已经。

下面代码的输出是以下颜色变化:



乍一看，这与 Floris 的解决方案非常相似，但仔细观察后，您可以清楚地看到许多情况下的差异。办公室主题颜色(以及此解决方案)通常比普通的 RGB 变亮/变暗技术更饱和。

Option Explicit

Public Type HSL
    h As Double ' Range 0 - 1
    S As Double ' Range 0 - 1
    L As Double ' Range 0 - 1
End Type

Public Type RGB
    R As Byte
    G As Byte
    B As Byte
End Type

Sub CalcColor()
    Dim ii As Integer, jj As Integer
    Dim pres As Presentation
    Dim schemeColors As ThemeColorScheme
    Dim ts As Double
    Dim c, c2 As Long
    Dim hc As HSL, hc2 As HSL

    Set pres = ActivePresentation
    Set schemeColors = pres.Designs(1).SlideMaster.Theme.ThemeColorScheme

    ' For all colors
    For ii = 0 To 11
      c = schemeColors(ii + 1).RGB

      ' Generate all the color variations
      For jj = 0 To 5
        hc = RGBtoHSL(c)
        ts = SelectTintOrShade(hc, jj)
        hc2 = ApplyTintAndShade(hc, ts)
        c2 = HSLtoRGB(hc2)
        Call CreateShape(pres.Slides(1), ii, jj, c2)
      Next jj
    Next ii

End Sub

' The tint and shade value is a value between -1.0 and 1.0, where
' -1.0 means fully shading (black), and 1.0 means fully tinting (white)
' A tint/shade value of 0.0 will not change the color
Public Function SelectTintOrShade(hc As HSL, variationIndex As Integer) As Double

    Dim shades(5) As Variant
    shades(0) = Array(0#, 0.5, 0.35, 0.25, 0.15, 0.05)
    shades(1) = Array(0#, 0.9, 0.75, 0.5, 0.25, 0.1)
    shades(2) = Array(0#, 0.8, 0.6, 0.4, -0.25, -0.5)
    shades(3) = Array(0#, -0.1, -0.25, -0.5, -0.75, -0.9)
    shades(4) = Array(0#, -0.05, -0.15, -0.25, -0.35, -0.5)

    Select Case hc.L
        Case Is < 0.001: SelectTintOrShade = shades(0)(variationIndex)
        Case Is < 0.2:   SelectTintOrShade = shades(1)(variationIndex)
        Case Is < 0.8:   SelectTintOrShade = shades(2)(variationIndex)
        Case Is < 0.999: SelectTintOrShade = shades(3)(variationIndex)
        Case Else:       SelectTintOrShade = shades(4)(variationIndex)
    End Select
End Function

Public Function ApplyTintAndShade(hc As HSL, TintAndShade As Double) As HSL

    If TintAndShade > 0 Then
        hc.L = hc.L + (1 - hc.L) * TintAndShade
    Else
        hc.L = hc.L + hc.L * TintAndShade
    End If

    ApplyTintAndShade = hc

End Function

Sub CreateShape(slide As slide, xIndex As Integer, yIndex As Integer, color As Long)

    Dim newShape As Shape
    Dim xStart As Integer, yStart As Integer
    Dim xOffset As Integer, yOffset As Integer
    Dim xSize As Integer, ySize As Integer
    xStart = 100
    yStart = 100
    xOffset = 30
    yOffset = 30
    xSize = 25
    ySize = 25

    Set newShape = slide.Shapes.AddShape(msoShapeRectangle, xStart + xOffset * xIndex, yStart + yOffset * yIndex, xSize, ySize)
    newShape.Fill.BackColor.RGB = color
    newShape.Fill.ForeColor.RGB = color
    newShape.Line.ForeColor.RGB = 0
    newShape.Line.BackColor.RGB = 0

End Sub

' From RGB to HSL

Function RGBtoHSL(ByVal RGB As Long) As HSL

    Dim R As Double ' Range 0 - 1
    Dim G As Double ' Range 0 - 1
    Dim B As Double ' Range 0 - 1

    Dim RGB_Max  As Double
    Dim RGB_Min  As Double
    Dim RGB_Diff As Double

    Dim HexString As String

    HexString = Right$(String$(7, "0") & Hex$(RGB), 8)
    R = CDbl("&H" & Mid$(HexString, 7, 2)) / 255
    G = CDbl("&H" & Mid$(HexString, 5, 2)) / 255
    B = CDbl("&H" & Mid$(HexString, 3, 2)) / 255

    RGB_Max = R
    If G > RGB_Max Then RGB_Max = G
    If B > RGB_Max Then RGB_Max = B

    RGB_Min = R
    If G < RGB_Min Then RGB_Min = G
    If B < RGB_Min Then RGB_Min = B

    RGB_Diff = RGB_Max - RGB_Min

    With RGBtoHSL

        .L = (RGB_Max + RGB_Min) / 2

        If RGB_Diff = 0 Then

            .S = 0
            .h = 0

        Else

            Select Case RGB_Max
                Case R: .h = (1 / 6) * (G - B) / RGB_Diff - (B > G)
                Case G: .h = (1 / 6) * (B - R) / RGB_Diff + (1 / 3)
                Case B: .h = (1 / 6) * (R - G) / RGB_Diff + (2 / 3)
            End Select

            Select Case .L
                Case Is < 0.5: .S = RGB_Diff / (2 * .L)
                Case Else:     .S = RGB_Diff / (2 - (2 * .L))
            End Select

        End If

    End With

End Function

' .. and back again

Function HSLtoRGB(ByRef HSL As HSL) As Long

    Dim R As Double
    Dim G As Double
    Dim B As Double

    Dim X As Double
    Dim Y As Double

    With HSL

        If .S = 0 Then

            R = .L
            G = .L
            B = .L

        Else

            Select Case .L
                Case Is < 0.5: X = .L * (1 + .S)
                Case Else:     X = .L + .S - (.L * .S)
            End Select

            Y = 2 * .L - X

            R = H2C(X, Y, IIf(.h > 2 / 3, .h - 2 / 3, .h + 1 / 3))
            G = H2C(X, Y, .h)
            B = H2C(X, Y, IIf(.h < 1 / 3, .h + 2 / 3, .h - 1 / 3))

        End If

    End With

    HSLtoRGB = CLng("&H00" & _
                    Right$("0" & Hex$(Round(B * 255)), 2) & _
                    Right$("0" & Hex$(Round(G * 255)), 2) & _
                    Right$("0" & Hex$(Round(R * 255)), 2))

End Function

Function H2C(X As Double, Y As Double, hc As Double) As Double

    Select Case hc
        Case Is < 1 / 6: H2C = Y + ((X - Y) * 6 * hc)
        Case Is < 1 / 2: H2C = X
        Case Is < 2 / 3: H2C = Y + ((X - Y) * ((2 / 3) - hc) * 6)
        Case Else:       H2C = Y
    End Select

End Function