static Boolean GetDeviceGammaRampGD (GDHandle hGD, Ptr pRamp)
{
GammaTblPtr pTableGammaTemp = NULL;
long indexChan, indexEntry;
OSErr err;
if (pRamp)
{
err = GetGammaTable (hGD, &pTableGammaTemp);
if ((noErr == err) && pTableGammaTemp)
{
unsigned char * pEntry = (unsigned char *) &pTableGammaTemp->gFormulaData + pTableGammaTemp->gFormulaSize;
short bytesPerEntry = (pTableGammaTemp->gDataWidth + 7) / 8;
short shiftRightValue = pTableGammaTemp->gDataWidth - 8;
short channels = pTableGammaTemp->gChanCnt;
short entries = pTableGammaTemp->gDataCnt;
if (3 == channels)
{
for (indexChan = 0; indexChan < channels; indexChan++)
for (indexEntry = 0; indexEntry < 256; indexEntry++)
*((unsigned char *) pRamp + (indexChan * 256) + indexEntry) =
*(pEntry + indexChan * entries * bytesPerEntry + indexEntry * entries * bytesPerEntry / 256) >> shiftRightValue;
}
else
{
for (indexChan = 0; indexChan < 768; indexChan += 256)
for (indexEntry = 0; indexEntry < 256; indexEntry++)
*((unsigned char *) pRamp + indexChan + indexEntry) =
*(pEntry + indexEntry * entries * bytesPerEntry / 256) >> shiftRightValue;
}
return true;
}
static Boolean GetDeviceGammaRampGD (GDHandle hGD, Ptr pRamp)
{
GammaTblPtr pTableGammaTemp = NULL;
long indexChan, indexEntry;
OSErr err;
if (pRamp) /* ensure pRamp is allocated */
{
err = GetGammaTable (hGD, &pTableGammaTemp); /* get a pointer to the current gamma */
if ((noErr == err) && pTableGammaTemp) /* if successful */
{
/* fill ramp */
unsigned char * pEntry = (unsigned char *) &pTableGammaTemp->gFormulaData + pTableGammaTemp->gFormulaSize; /* base of table */
short bytesPerEntry = (pTableGammaTemp->gDataWidth + 7) / 8; /* size, in bytes, of the device table entries */
short shiftRightValue = pTableGammaTemp->gDataWidth - 8; /* number of right shifts device -> ramp */
short channels = pTableGammaTemp->gChanCnt;
short entries = pTableGammaTemp->gDataCnt;
if (3 == channels) /* RGB format */
{ /* note, this will create runs of entries if dest. is bigger (not linear interpolate) */
for (indexChan = 0; indexChan < channels; indexChan++)
for (indexEntry = 0; indexEntry < 256; indexEntry++)
*((unsigned char *) pRamp + (indexChan * 256) + indexEntry) =
*(pEntry + indexChan * entries * bytesPerEntry + indexEntry * entries * bytesPerEntry / 256) >> shiftRightValue;
}
else /* single channel format */
{
for (indexChan = 0; indexChan < 768; indexChan += 256) /* repeat for all 3 channels (step by ramp size) */
for (indexEntry = 0; indexEntry < 256; indexEntry++) /* for all entries set vramp value */
*((unsigned char *) pRamp + indexChan + indexEntry) =
*(pEntry + indexEntry * entries * bytesPerEntry / 256) >> shiftRightValue;
}
return true;
}
static Ptr GetDeviceGamma (GDHandle hGD)
{
GammaTblPtr pTableGammaDevice = NULL;
GammaTblPtr pTableGammaReturn = NULL;
OSErr err;
err = GetGammaTable (hGD, &pTableGammaDevice);
if ((noErr == err) && pTableGammaDevice)
pTableGammaReturn = (GammaTblPtr) CopyGammaTable (pTableGammaDevice);
return (Ptr) pTableGammaReturn;
}
static Ptr GetDeviceGamma (GDHandle hGD)
{
GammaTblPtr pTableGammaDevice = NULL;
GammaTblPtr pTableGammaReturn = NULL;
OSErr err;
err = GetGammaTable (hGD, &pTableGammaDevice); /* get a pointer to the devices table */
if ((noErr == err) && pTableGammaDevice) /* if succesful */
pTableGammaReturn = (GammaTblPtr) CopyGammaTable (pTableGammaDevice); /* copy to global */
return (Ptr) pTableGammaReturn;
}
