GreDeviceSetAVIOFont

GreDeviceSetAVIOFont loads or deletes an image font used by the AVIO presentation space associated with the device context.

Simulation support

This function is mandatory for display drivers. For other drivers, it is simulated by a handling routine in the graphics engine.

Syntax

GreDeviceSetAVIOFont(hdc, pLogFont, pFontDef, lcid, pInstance, lFunction)

Parameters

hdc (HDC) - input

The device context handle.

pLogFont (PFATTRS) - input

A pointer to a logical font.

pFontDef (PBYTE) - input

A pointer to a physical font data structure. When the value passed is 0, the handling routine must delete the loaded font corresponding to lLcid. If the high-order bit of the high-order WORD in lLcid is set, the handle is for a device font.

lcid (LONG) - input

Local identifier value of -2, -3, or -4.

pInstance (PVOID) - input

A pointer to instance data.

lFunction (ULONG) - input

High-order WORD=flags; low-order WORD=NGreDeviceSetAVIOFont.

Returns

fSuccess (BOOL) - returns

Return codes.

On completion, the handling routine must return BOOLEAN (fSuccess).

• TRUE Successful. The font is acceptable for use with an AVIO presentation space.
• FALSE Error.

Remarks

When loaded, the font is used by subsequent GreCharRect, GreCharStr, and GreScrollRect calls to draw the character images for the appropriate AVIO set. lLcid identifiers LCID_AVIO_1, LCID_AVIO_2, and LCID_AVIO_3 correspond to AVIO sets 1, 2, and 3 respectively.

If the font is not acceptable for use with an AVIO presentation space, the handling routine returns FALSE to indicate an error. The font must be a fixed-pitch image (raster) font that matches one of the cell sizes for the default font. If the font does not match a supported cell size, the characters are displayed in the presentation space as black cells.

A possible approach is for the presentation driver to realize the AVIO fonts required and store the pointers to the fonts in the DC instance data structure.