📄 libmng_pixels.c
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for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
{ /* scale down by dropping the LSB */
*pScanline = *pDataline;
*(pScanline+1) = *(pDataline+2);
*(pScanline+2) = *(pDataline+4);
*(pScanline+3) = *(pDataline+6);
pScanline += (pData->iColinc << 2);
pDataline += 8;
}
}
else
#endif
{
for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
{ /* copy the values */
*pScanline = *pDataline;
*(pScanline+1) = *(pDataline+1);
*(pScanline+2) = *(pDataline+2);
*(pScanline+3) = *(pDataline+3);
pScanline += (pData->iColinc << 2);
pDataline += 4;
}
}
}
else
{
#ifndef MNG_NO_16BIT_SUPPORT
if (pData->bIsRGBA16) /* 16-bit input row ? */
{
for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
{ /* get alpha values */
iFGa16 = mng_get_uint16 (pDataline+6);
iBGa16 = (mng_uint16)(*(pScanline+3));
iBGa16 = (mng_uint16)(iBGa16 << 8) | iBGa16;
if (iFGa16) /* any opacity at all ? */
{ /* fully opaque or background fully transparent ? */
if ((iFGa16 == 0xFFFF) || (iBGa16 == 0))
{ /* plain copy it */
*pScanline = *pDataline;
*(pScanline+1) = *(pDataline+2);
*(pScanline+2) = *(pDataline+4);
*(pScanline+3) = *(pDataline+6);
}
else
{
if (iBGa16 == 0xFFFF) /* background fully opaque ? */
{ /* get the proper values */
#ifdef MNG_OPTIMIZE_FOOTPRINT_COMPOSE
int i;
for (i=2; i >= 0; i--)
{
iFGg16 = mng_get_uint16 (pDataline+i+i);
/* scale background up */
iBGg16 = (mng_uint16)(*(pScanline+i));
iBGg16 = (mng_uint16)((mng_uint32)iBGg16 << 8) | iBGg16;
/* now compose */
MNG_COMPOSE16(iFGg16, iFGg16, iFGa16, iBGg16)
/* and return the composed values */
*(pScanline+i) = (mng_uint8)(iFGg16 >> 8);
/* alpha remains fully opaque !!! */
}
#else
iFGr16 = mng_get_uint16 (pDataline );
iFGg16 = mng_get_uint16 (pDataline+2);
iFGb16 = mng_get_uint16 (pDataline+4);
/* scale background up */
iBGr16 = (mng_uint16)(*pScanline );
iBGg16 = (mng_uint16)(*(pScanline+1));
iBGb16 = (mng_uint16)(*(pScanline+2));
iBGr16 = (mng_uint16)((mng_uint32)iBGr16 << 8) | iBGr16;
iBGg16 = (mng_uint16)((mng_uint32)iBGg16 << 8) | iBGg16;
iBGb16 = (mng_uint16)((mng_uint32)iBGb16 << 8) | iBGb16;
/* now compose */
MNG_COMPOSE16(iFGr16, iFGr16, iFGa16, iBGr16)
MNG_COMPOSE16(iFGg16, iFGg16, iFGa16, iBGg16)
MNG_COMPOSE16(iFGb16, iFGb16, iFGa16, iBGb16)
/* and return the composed values */
*pScanline = (mng_uint8)(iFGr16 >> 8);
*(pScanline+1) = (mng_uint8)(iFGg16 >> 8);
*(pScanline+2) = (mng_uint8)(iFGb16 >> 8);
/* alpha remains fully opaque !!! */
#endif
}
else
{ /* scale background up */
iBGr16 = (mng_uint16)(*pScanline );
iBGg16 = (mng_uint16)(*(pScanline+1));
iBGb16 = (mng_uint16)(*(pScanline+2));
iBGr16 = (mng_uint16)((mng_uint32)iBGr16 << 8) | iBGr16;
iBGg16 = (mng_uint16)((mng_uint32)iBGg16 << 8) | iBGg16;
iBGb16 = (mng_uint16)((mng_uint32)iBGb16 << 8) | iBGb16;
/* let's blend */
MNG_BLEND16 (mng_get_uint16 (pDataline ),
mng_get_uint16 (pDataline+2),
mng_get_uint16 (pDataline+4), iFGa16,
iBGr16, iBGg16, iBGb16, iBGa16,
iCr16, iCg16, iCb16, iCa16)
/* and return the composed values */
*pScanline = (mng_uint8)(iCr16 >> 8);
*(pScanline+1) = (mng_uint8)(iCg16 >> 8);
*(pScanline+2) = (mng_uint8)(iCb16 >> 8);
*(pScanline+3) = (mng_uint8)(iCa16 >> 8);
}
}
}
pScanline += (pData->iColinc << 2);
pDataline += 8;
}
}
else
#endif
{
for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
{
iFGa8 = *(pDataline+3); /* get alpha values */
iBGa8 = *(pScanline+3);
if (iFGa8) /* any opacity at all ? */
{ /* fully opaque or background fully transparent ? */
if ((iFGa8 == 0xFF) || (iBGa8 == 0))
{ /* then simply copy the values */
*pScanline = *pDataline;
*(pScanline+1) = *(pDataline+1);
*(pScanline+2) = *(pDataline+2);
*(pScanline+3) = *(pDataline+3);
}
else
{
if (iBGa8 == 0xFF) /* background fully opaque ? */
{ /* do alpha composing */
#ifdef MNG_OPTIMIZE_FOOTPRINT_COMPOSE
int i;
for (i=2; i >= 0; i--)
{
MNG_COMPOSE8 (*(pScanline+i), *(pDataline+i), iFGa8, *(pScanline+i))
}
#else
MNG_COMPOSE8 (*pScanline, *pDataline, iFGa8, *pScanline )
MNG_COMPOSE8 (*(pScanline+1), *(pDataline+1), iFGa8, *(pScanline+1))
MNG_COMPOSE8 (*(pScanline+2), *(pDataline+2), iFGa8, *(pScanline+2))
#endif
/* alpha remains fully opaque !!! */
}
else
{ /* now blend */
MNG_BLEND8 (*pDataline, *(pDataline+1), *(pDataline+2), iFGa8,
*pScanline, *(pScanline+1), *(pScanline+2), iBGa8,
iCr8, iCg8, iCb8, iCa8)
/* and return the composed values */
*pScanline = iCr8;
*(pScanline+1) = iCg8;
*(pScanline+2) = iCb8;
*(pScanline+3) = iCa8;
}
}
}
pScanline += (pData->iColinc << 2);
pDataline += 4;
}
}
}
}
check_update_region (pData);
#ifdef MNG_SUPPORT_TRACE
MNG_TRACE (pData, MNG_FN_DISPLAY_RGBA8, MNG_LC_END)
#endif
return MNG_NOERROR;
}
#endif /* MNG_SKIPCANVAS_RGBA8 */
/* ************************************************************************** */
#ifndef MNG_SKIPCANVAS_RGBA8_PM
mng_retcode mng_display_rgba8_pm (mng_datap pData)
{
mng_uint8p pScanline;
mng_uint8p pDataline;
mng_int32 iX;
mng_uint32 s, t;
#ifdef MNG_SUPPORT_TRACE
MNG_TRACE (pData, MNG_FN_DISPLAY_RGBA8_PM, MNG_LC_START)
#endif
/* viewable row ? */
if ((pData->iRow >= pData->iSourcet) && (pData->iRow < pData->iSourceb))
{ /* address destination row */
pScanline = (mng_uint8p)pData->fGetcanvasline (((mng_handle)pData),
pData->iRow + pData->iDestt -
pData->iSourcet);
/* adjust destination row starting-point */
pScanline = pScanline + (pData->iCol << 2) + (pData->iDestl << 2);
pDataline = pData->pRGBArow; /* address source row */
#ifndef MNG_NO_16BIT_SUPPORT
if (pData->bIsRGBA16) /* adjust source row starting-point */
pDataline = pDataline + ((pData->iSourcel / pData->iColinc) << 3);
else
#endif
pDataline = pDataline + ((pData->iSourcel / pData->iColinc) << 2);
if (pData->bIsOpaque) /* forget about transparency ? */
{
#ifndef MNG_NO_16BIT_SUPPORT
if (pData->bIsRGBA16) /* 16-bit input row ? */
{
for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
{ /* scale down by dropping the LSB */
if ((s = pDataline[6]) == 0)
*(mng_uint32*) pScanline = 0; /* set all components = 0 */
else
{
if (s == 255)
{
pScanline[0] = pDataline[0];
pScanline[1] = pDataline[2];
pScanline[2] = pDataline[4];
pScanline[3] = 255;
}
else
{
#ifdef MNG_OPTIMIZE_FOOTPRINT_DIV
int i;
for (i=2; i >= 0; i--)
{
pScanline[2-i] = DIV255B8(s * pDataline[4-i-i]);
}
#else
pScanline[0] = DIV255B8(s * pDataline[0]);
pScanline[1] = DIV255B8(s * pDataline[2]);
pScanline[2] = DIV255B8(s * pDataline[4]);
#endif
pScanline[3] = (mng_uint8)s;
}
}
pScanline += (pData->iColinc << 2);
pDataline += 8;
}
}
else
#endif
{
for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
{ /* copy the values and premultiply */
if ((s = pDataline[3]) == 0)
*(mng_uint32*) pScanline = 0; /* set all components = 0 */
else
{
if (s == 255)
{
#ifdef MNG_BIGENDIAN_SUPPORTED
*(mng_uint32*)pScanline = (*(mng_uint32*)pDataline) | 0x000000FF;
#else
pScanline[0] = pDataline[0];
pScanline[1] = pDataline[1];
pScanline[2] = pDataline[2];
pScanline[3] = 255;
#endif
}
else
{
#ifdef MNG_OPTIMIZE_FOOTPRINT_DIV
int i;
for (i=2; i >= 0; i--)
{
pScanline[2-i] = DIV255B8(s * pDataline[2-i]);
}
#else
pScanline[0] = DIV255B8(s * pDataline[0]);
pScanline[1] = DIV255B8(s * pDataline[1]);
pScanline[2] = DIV255B8(s * pDataline[2]);
#endif
pScanline[3] = (mng_uint8)s;
}
}
pScanline += (pData->iColinc << 2);
pDataline += 4;
}
}
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