gistfile1.java

private void drawLineBresenham (int startX, int startY, int endX, int endY, G_Color color) {
	int dY = endY - startY;
	int dX = endX - startX;
	int fraction, stepX, stepY;

	if (dY < 0) {
		dY = -dY;
		stepY = -1;
	} else {
		stepY = 1;
	}

	if (dX < 0) {
		dX = -dX;
		stepX = -1;
	} else {
		stepX = 1;
	}

	dY = 2 * dY;
	dX = 2 * dX;

	putPixel (startX, startY, color);

	if (dX > dY) {
		fraction = (2 * dY) - dX;

		while (startX != endX) {
			if (fraction >= 0) {
				startY += stepY;
				fraction -= dX;
			}

			startX += stepX;
			fraction += dY;

			putPixel (startX, startY, color);
		}
	} else {
		fraction = (2 * dX) - dY;

		while (startY != endY) {
			if (fraction >= 0) {
				startX += stepX;
				fraction -= dY;
			}

			startY += stepY;
			fraction += dX;

			putPixel (startX, startY, color);
		}
	}
}