IDXGradient Interface

The IDXGradient interface produces gradient images that fade gradually from one color to another. It is used like a transform that has no input surfaces and produces one DXSurface object as output. The output surface is determined by setting a start color, end color, and choosing either a horizontal or vertical gradient.

This interface inherits from the IDXTScaleOutput interface, which enables you to set the output size of the gradient surface.

IDXGradient Methods

GetOutputSize Retrieves the size of the output surface.

SetGradient Sets the parameters used to produce the gradient surface.

IDXGradient::GetOutputSize

IDXGradient Interface

Retrieves the size of the output surface.

Syntax

HRESULT GetOutputSize(
    SIZE *pOutSize
);

Parameters

pOutSize

[out] Pointer to the SIZE structure that stores the height and width of the output surface, in pixels.

Return Value

Returns an HRESULT value that depends on the implementation of the interface.

Remarks

You can set this size with the IDXTScaleOutput interface.

IDXGradient::SetGradient

IDXGradient Interface

Sets the parameters used to produce the gradient surface.

Syntax

HRESULT SetGradient(
    DXSAMPLE StartColor,
    DXSAMPLE EndColor,
    BOOL bHorizontal
);

Parameters

StartColor

[in] Start color in DXSAMPLE format.

EndColor

[out] End color in DXSAMPLE format.

bHorizontal

[out] Boolean value that indicates the gradient direction. If TRUE, the gradient is horizontal; if FALSE, the gradient is vertical.

Return Value

Returns an HRESULT value that depends on the implementation of the interface.

Remarks

The start color is on the left of the image for horizontal gradients and on the top of the image for vertical gradients.

GetOutputSize	Retrieves the size of the output surface.
SetGradient	Sets the parameters used to produce the gradient surface.