Name

Type

Optional

Meaning

hWnd

Number

No

Handle to the layered window.

A layered window is created by specifying %WS_EX_LAYERED when creating the window or by setting %WS_EX_LAYERED via WIN_SetWindowLong after the window has been created.

crKey

Number

No

Specifies the transparency color key to be used when composing the layered window. Use RGB function to compose requested color

All pixels painted by the window in this color will be transparent.

bAlpha

Number

No

Alpha value used to describe the opacity of the layered window.

When bAlpha is 0, the window is completely transparent.

When bAlpha is 255, the window is opaque.

dwFlags

Number

No

Specifies an action to take. This parameter can be one or more of the following values:

%LWA_COLORKEY

Use crKey as the transparency color.

%LWA_ALPHA

Use bAlpha to determine the opacity of the layered window.