BitBltFxSys

Copy a linear block of video memory to another location in video memory with optional effects.

Declaration

void NAPI GA_2DRenderFuncs::BitBltFxSys(
void *srcAddr,
N_int32 srcPitch,
N_int32 srcLeft,
N_int32 srcTop,
N_int32 srcWidth,
N_int32 srcHeight,
N_int32 dstLeft,
N_int32 dstTop,
N_int32 dstWidth,
N_int32 dstHeight,
GA_bltFx *fx)

Prototype In

snap/graphics.h

Parameters

srcAddr | Address of source bitmap in system memory
srcPitch | Pitch of source bitmap in bytes
srcLeft | Left coordinate of the source rectangle to copy
srcTop | Top coordinate of the source rectangle to copy
srcWidth | Width of the source rectangle in pixels
srcHeight | Height of the source rectangle in scanlines
dstLeft | Left coordinate of destination
dstTop | Top coordinate of destination
dstWidth | Width of the destination rectangle in pixels
dstHeight | Height of the destination rectangle in scanlines
fx | GA_bltFx structure describing the requested effects

Description

This function copies a bitmap from system memory with a starting address of srcAddr to video memory with the optional features described in the GA_bltFx structure. Currently this function can perform stretching, source and destination transparency and flipping depending on what features the underlying hardware supports, with an optional mix code. This routine will copy the region (srcLeft, srcTop, srcLeft+srcWidth-1, srcTop+srcHeight-1) from the source bitmap to (dstLeft, dstTop, dstLeft+dstWidth-1, dstTop+dstHeight-1) in video memory. Note that the source and destination rectangle dimensions may be different in, which is the case for doing a copy with bitmap stretching. If the GA_bltFx structure does not indicate stretching is in effect, the dstHeight and dstWidth parameters will be ignored and only the srcWidth and srcHeight parameters will be used.

Note that the srcLeft and srcTop coordinates define an offset within the source bitmap to be copied, so it will copy only a portion of an offscreen bitmap. This is useful for storing multiple images in a single offscreen bitmap, or for handling the case of software clipping offscreen bitmaps if the destination lies outside of the software clip rectangle for the destination buffer.

Note: Some of the features may not be supported at the same time, and it is up to the application programmer to call the BitBltFxTest function to determine what features are supported before calling this function. Calling this function with an unsupported set of features will result in undefined behaviour.

See Also

BitBltFxTest, BitBltFx, BitBltFxLin, BitBltFxBM, SrcTransBlt, DstTransBlt, BitBlt

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