//
// gradient_int.cc
//
// Colour utility functions
//
// Copyright (c) J. Belson	2000.03.29
//


#include "gradient_int.h"


gradient_int::gradient_int( uchar r1, uchar g1, uchar b1,
					uchar r2, uchar g2, uchar b2, int step)
{
	col_r = r1<<16;
	col_g = g1<<16;
	col_b = b1<<16;

	step_r = step_g = step_b = 0;

	if (step) {
		step_r = ((r2 - r1)<<16) / step;
		step_g = ((g2 - g1)<<16) / step;
		step_b = ((b2 - b1)<<16) / step;
	}
}


void gradient_int::set(  uchar r1, uchar g1, uchar b1,
				uchar r2, uchar g2, uchar b2, int step)
{
	col_r = r1<<16;
	col_g = g1<<16;
	col_b = b1<<16;

	step_r = step_g = step_b = 0;
	
	if (step) {
		step_r = ((r2 - r1)<<16) / step;
		step_g = ((g2 - g1)<<16) / step;
		step_b = ((b2 - b1)<<16) / step;
	}
}


void gradient_int::get_next(uchar &r, uchar &g, uchar &b)
{
	r = col_r>>16;
	g = col_g>>16;
	b = col_b>>16;

	col_r += step_r;
	col_g += step_g;
	col_b += step_b;
}