亮度属性 （ActiveX）

签名

工 务 局：

object.Brightness

对象

类型：地理地图图像，栅格图像，擦除

此属性适用的对象。

属性值

只读：不

类型：整数

亮度值是介于 0 和 100 之间的正整数（包括 0 和 100）。默认值为 50。

言论

您可以调整图像亮度、对比度和淡入淡出以显示图像以及打印输出，而不会影响原始光栅图像文件。调整亮度以使图像变暗或变亮。调整对比度以使质量较差的图像更易于阅读。调整淡入淡出以使矢量更易于在图像上看到，并在打印的输出中创建水印效果。

黑白图像无法针对亮度、对比度或淡入淡出进行调整。

例子

工 务 局：

Sub Example_Brightness()
    ' This example inserts a raster image and finds the current
    ' brightness of the image. It then changes the brightness
    ' of the image.
    
    ' This example uses the "2d Projected Polylines.jpg." found in the Sample
    ' directory. If you do not have this image, or if it is located
    ' in a different directory, insert a valid path and file name
    ' for the imageName variable below.
    Dim insertionPoint(0 To 2) As Double
    Dim scalefactor As Double
    Dim rotAngleInDegree As Double, rotAngle As Double
    Dim imageName As String
    Dim raster As AcadRasterImage
    imageName = "C:/AutoCAD/sample/2d Projected Polylines.jpg"
    
    insertionPoint(0) = 2#: insertionPoint(1) = 2#: insertionPoint(2) = 0#
    scalefactor = 1#
    rotAngleInDegree = 0#
    rotAngle = rotAngleInDegree * 3.141592 / 180#
    
    On Error Resume Next
    
    ' Creates a raster image in model space
    Set raster = ThisDrawing.ModelSpace.AddRaster(imageName, insertionPoint, scalefactor, rotAngle)
    If Err.Description = "File error" Then
        MsgBox imageName & " could not be found."
        Exit Sub
    End If

    ' Find the current brightness
    ThisDrawing.Regen True
    MsgBox "The brightness is currently set to: " & raster.Brightness, vbInformation
    
    ' Change the brightness to 5
    raster.Brightness = 5
    ThisDrawing.Regen True
    MsgBox "The brightness is now set to: " & raster.Brightness, vbInformation
End Sub

Visual LISP：

(vl-load-com)
(defun c:Example_Brightness()
    ;; This example inserts a raster image and finds the current
    ;; brightness of the image. It then changes the brightness
    ;; of the image.
    (setq acadObj (vlax-get-acad-object))
    (setq doc (vla-get-ActiveDocument acadObj))

    ;; This example uses the "2d Projected Polylines.jpg" found in the Sample
    ;; directory. If you do not have this image, or if it is located
    ;; in a different directory, insert a valid path and file name
    ;; for the imageName variable below.
    (setq insertionPoint (vlax-3d-point 2 2 0)
          imageName ".\\Sample\\VBA\\2d Projected Polylines.jpg"
          scalefactor 1
          rotAngleInDegree 0
          rotAngle (/ (* rotAngleInDegree 3.141592) 180))

    (if (/= (findfile ".\\Sample\\VBA\\2d Projected Polylines.jpg") nil)
        (progn
            ;; Creates a raster image in model space
            (setq modelSpace (vla-get-ModelSpace doc))
            (setq raster (vla-AddRaster modelSpace (findfile ".\\Sample\\VBA\\2d Projected Polylines.jpg") insertionPoint scalefactor rotAngle))
            (vla-ZoomExtents acadObj)

            ;; Find the current brightness
            (vla-Regen doc :vlax-true)
            (alert (strcat "The brightness is currently set to: " (rtos (vla-get-Brightness raster) 2)))
    
            ;; Change the brightness to 5
            (vla-put-Brightness raster 5)
            (vla-Regen doc :vlax-true)
            (alert (strcat "The brightness is now set to: " (rtos (vla-get-Brightness raster) 2)))	  
	)
        (alert (strcat imageName " could not be found."))
    )
)