// An improved colorRamp() function and call (Revised 2/21/2012):

// The function:

//--------------------------------------------------- Color Ramp Version 2012
TColor colorRamp(int part, int whole)
{
	if (whole == 0) whole = 1;             // prevent divide by zero
	part = part % whole;                   // keep part <= whole
	int pixelDistanceAlongEdges = (part * 1792) / whole;
	int red, green, blue;
	// Which edge of the color cube are we on?
	if (pixelDistanceAlongEdges < 256) {        // from BLACK to BLUE
		red = 0; green = 0; blue = pixelDistanceAlongEdges;
	}
	else if (pixelDistanceAlongEdges < 512) {   // from BLUE to CYAN
		red = 0; green = pixelDistanceAlongEdges - 256; blue = 255;
	}
	else if (pixelDistanceAlongEdges < 768) {   // from CYAN to GREEN
		red = 0; green = 255; blue = 255 - (pixelDistanceAlongEdges - 512);
	}
	else if (pixelDistanceAlongEdges < 1024) {  // from GREEN to YELLOW
		red = (pixelDistanceAlongEdges - 768); green = 255; blue = 0;
	}
	else if (pixelDistanceAlongEdges < 1280) {  // from YELLOW to RED
		red = 255; green= 255-(pixelDistanceAlongEdges - 1024); blue = 0;
	}
	else if (pixelDistanceAlongEdges < 1536) {  // from RED to MAGENTA
		red = 255; green= 0; blue = pixelDistanceAlongEdges - 1280;
	}
	else {                                     // from MAGENTA to WHITE
		red = 255; green = pixelDistanceAlongEdges - 1537; blue = 255;
	}
	return static_cast<TColor>(RGB(red, green, blue));
}

// The call:

Form1->PaintBox1->Canvas->Pixels[i][j] = colorRamp(part, whole);