SetViewPortPixel function - Drawing from Bitmap

[DOrmisher]

I'm currently trying to draw a bitmap to screen after a mouse click. This is the draw sprite function:

void C_AlphaBlend::DrawSprite( int X, int Y, Bitmap* BitmapToDraw )
{
	int Width=BitmapToDraw->Width;
	int Height=BitmapToDraw->Height;

	for (int i=0; i<Width; i++)
	{
		for (int j=0; j<Height; j++)
		{
			Color colour = BitmapToDraw->GetPixel(i, j);

			if(colour.A!=0)
			{
				//Need to set viewport pixel here
			}
		}
	}
}

The problem I'm having is I'm not sure how to actually implement a function that draws directly to the screen, or if there is a simple function that can be used.

Please help me out guys!