IBrush interface

The interface that every brush of the package implements. Brush is another name for it.

A brush decides what a fill method of Graphics puts inside a shape, and what a Pen draws with. The package has five kinds of brush, one class each:

Class	Fills with
SolidBrush	One colour.
HatchBrush	A pattern of lines or dots in two colours.
LinearGradientBrush	A colour that changes along a line.
PathGradientBrush	A colour that changes from a centre point to the edge of a path.
TextureBrush	An image, repeated.

Because every class implements IBrush, a parameter or a variable declared As Brush takes any of them, and the type of an object that came back as a Brush can be asked with Type.

What the brushes share
- Colours
Members
Example
See Also

Each brush class is created with New or with the function of the same name, for example New SolidBrush(color) and SolidBrush(color). The two are one thing and are documented once, under Creating on the page of the class.

Each brush class inherits from GdiPlusBase, so it has the LastResult property: the last status that GDI+ reported as a failure, or Ok. Unless the program sets GdipErrorHandlingStrategy, a failure raises no error.

Note 0.9.45.0

LastResult keeps the last failure until ClearResult is called. A property that returns an object returns Nothing while LastResult is not Ok, even when the failure was an earlier, unrelated call, and Clone does the same.

A brush deletes its GDI+ object when the last reference to the brush is released.

Colours

Every brush that takes colours has two forms: one with Color parameters, and one with Long parameters, which are the rgb forms. The Color forms are the ones to use.

Warning 0.9.45.0

A Long passed to an rgb parameter is read as &H00RRGGBB: red in the third byte and blue in the first. It is not a VB colour (a COLORREF, &H00BBGGRR), so SolidBrush(vbRed) and SolidBrush(RGB(255, 0, 0)) paint blue, and the colour constants of VB and the system colours (vbButtonFace, &H8000000F) are not translated. The alpha byte of the Long is dropped, so the result is always opaque. A member of CColor passed there binds to the Long form and loses its alpha: SolidBrush(CColor.Transparent) fills opaque white. Pass Color(alpha, red, green, blue), or Color(CColor.Transparent), to get the colour that was meant.

Members

CloneBrush

Syntax: copy = brush.CloneBrush( )

Returns a new brush of the same class with the same settings, as an IBrush. Changing the copy does not change the original. The class of the copy is the class of the original: a Brush variable that holds a HatchBrush gives a HatchBrush back, and can be assigned to a HatchBrush variable.

Each class has a Clone method as well, which returns the copy as the class itself.

NativeBrush

Syntax: handle = brush.NativeBrush

Returns the GDI+ handle of the brush, wrapped in a structure. It is for a program that calls the GDI+ functions directly; the handle belongs to the brush and must not be deleted.

Type

Syntax: type = brush.Type

Returns a GpBrushType value for the kind of the brush: BrushTypeSolidColor, BrushTypeHatchFill, BrushTypeTextureFill, BrushTypePathGradient or BrushTypeLinearGradient. The property is read-only.

Warning 0.9.45.0

Reading Type of a PathGradientBrush stops a program that runs in the IDE, at an assertion that expects a linear gradient. A compiled program is not affected, and returns BrushTypePathGradient.

Example

Dim user As GdiPlusUser = GdiPlusUser()

Dim brushes(1 To 3) As Brush
Set brushes(1) = New SolidBrush(Color(255, 0, 128, 0))
Set brushes(2) = New HatchBrush(HatchStyleCross, Color(255, 255, 0, 0), Color(255, 255, 255, 255))
Set brushes(3) = New LinearGradientBrush(GpPointF(0, 0), GpPointF(10, 0), Color(255, 0, 0, 0), Color(255, 255, 255, 255))

Dim i As Long
Dim copy As Brush
For i = 1 To 3
    Set copy = brushes(i).CloneBrush()
    Debug.Print brushes(i).Type & " " & copy.Type
Next

Dim hatch As HatchBrush = brushes(2).CloneBrush()
Debug.Print hatch.HatchStyle = HatchStyleCross
' Output:
' 0 0
' 1 1
' 4 4
' True