CxImage设置透明色的方法:
void SetImageTransColor( CxImage* pImg, BYTE R, BYTE G, BYTE B )
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{
if (pImg == NULL) return;
if (pImg->GetTransIndex() != 24)
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{
pImg->IncreaseBpp(24);
}
pImg->SetTransIndex(0);
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RGBQUAD rgbTrans =
{B, G, R, 0};
pImg->SetTransColor(rgbTrans);
}经过这样设置透明色的图,如果使用CxImage::Stretch进行缩放绘制,绘制透明色并不会透明,而会原汁原味的将透明色如实的绘制上去,经过测试,使用CxImage::Draw2这个方法缩放绘制是没有问题的.