MagSetFullscreenColorEffect function (magnification.h)

Changes the color transformation matrix associated with the full-screen magnifier.

Syntax

BOOL MagSetFullscreenColorEffect(
  [in] PMAGCOLOREFFECT pEffect
);

Parameters

[in] pEffect

Type: PMAGCOLOREFFECT

The new color transformation matrix. This parameter must not be NULL.

Return value

Type: BOOL

Returns TRUE if successful, or FALSE otherwise.

Remarks

The full-screen magnifier uses the color transformation matrix to apply a color effect to the entire desktop. If the function is called multiple times, the most recent color transform is used.

Examples

The following example defines two color transformation matrices for use with MagSetFullscreenColorEffect. The g_MagEffectGrayscale matrix converts the screen colors to grayscale. The g_MagEffectIdentity matrix is the identity matrix, which restores the original screen colors.

// Initialize color transformation matrices used to apply grayscale and to 
// restore the original screen color.
MAGCOLOREFFECT g_MagEffectGrayscale = {0.3f,  0.3f,  0.3f,  0.0f,  0.0f,
                                       0.6f,  0.6f,  0.6f,  0.0f,  0.0f,
                                       0.1f,  0.1f,  0.1f,  0.0f,  0.0f,
                                       0.0f,  0.0f,  0.0f,  1.0f,  0.0f,
                                       0.0f,  0.0f,  0.0f,  0.0f,  1.0f};

MAGCOLOREFFECT g_MagEffectIdentity = {1.0f,  0.0f,  0.0f,  0.0f,  0.0f,
                                      0.0f,  1.0f,  0.0f,  0.0f,  0.0f,
                                      0.0f,  0.0f,  1.0f,  0.0f,  0.0f,
                                      0.0f,  0.0f,  0.0f,  1.0f,  0.0f,
                                      0.0f,  0.0f,  0.0f,  0.0f,  1.0f};

BOOL SetColorGrayscale(__in BOOL fGrayscaleOn)
{
    // Apply the color matrix required to either apply grayscale to the screen 
    // colors or to show the regular colors.
    PMAGCOLOREFFECT pEffect = 
                (fGrayscaleOn ? &g_MagEffectGrayscale : &g_MagEffectIdentity);

    return MagSetFullscreenColorEffect(pEffect);
}

Requirements

Requirement Value
Minimum supported client Windows 8 [desktop apps only]
Minimum supported server Windows Server 2012 [desktop apps only]
Target Platform Windows
Header magnification.h
Library Magnification.lib
DLL Magnification.dll

See also

MagGetFullscreenColorEffect