/*
 * Copyright 2011, Blender Foundation.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * Contributor: 
 *		Jeroen Bakker 
 *		Monique Dewanchand
 */

#include "COM_DoubleEdgeMaskOperation.h"
#include "BLI_math.h"
#include "DNA_node_types.h"
#include "MEM_guardedalloc.h"

// this part has been copied from the double edge mask
// Contributor(s): Peter Larabell.
static void do_adjacentKeepBorders(unsigned int t, unsigned int rw, unsigned int *limask, unsigned int *lomask, unsigned int *lres, float *res, unsigned int *rsize)
{
	int x;
	unsigned int isz = 0; // inner edge size
	unsigned int osz = 0; // outer edge size
	unsigned int gsz = 0; // gradient fill area size
	/* Test the four corners */
	/* upper left corner */
	x = t - rw + 1;
	// test if inner mask is filled
	if (limask[x]) {
		// test if pixel underneath, or to the right, are empty in the inner mask,
		// but filled in the outer mask
		if ((!limask[x - rw] && lomask[x - rw]) || (!limask[x + 1] && lomask[x + 1])) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		osz++;                                   // increment outer edge size
		lres[x] = 3;                             // flag pixel as outer edge
	}
	/* upper right corner */
	x = t;
	// test if inner mask is filled
	if (limask[x]) {
		// test if pixel underneath, or to the left, are empty in the inner mask,
		// but filled in the outer mask
		if ((!limask[x - rw] && lomask[x - rw]) || (!limask[x - 1] && lomask[x - 1])) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                         // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		osz++;                                   // increment outer edge size
		lres[x] = 3;                             // flag pixel as outer edge
	}
	/* lower left corner */
	x = 0;
	// test if inner mask is filled
	if (limask[x]) {
		// test if pixel above, or to the right, are empty in the inner mask,
		// but filled in the outer mask
		if ((!limask[x + rw] && lomask[x + rw]) || (!limask[x + 1] && lomask[x + 1])) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		osz++;                                   // increment outer edge size
		lres[x] = 3;                             // flag pixel as outer edge
	}
	/* lower right corner */
	x = rw - 1;
	// test if inner mask is filled
	if (limask[x]) {
		// test if pixel above, or to the left, are empty in the inner mask,
		// but filled in the outer mask
		if ((!limask[x + rw] && lomask[x + rw]) || (!limask[x - 1] && lomask[x - 1])) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		osz++;                                   // increment outer edge size
		lres[x] = 3;                             // flag pixel as outer edge
	}
	
	/* Test the TOP row of pixels in buffer, except corners */
	for (x = t - 1; x >= (t - rw) + 2; x--) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if pixel to the right, or to the left, are empty in the inner mask,
			// but filled in the outer mask
			if ((!limask[x - 1] && lomask[x - 1]) || (!limask[x + 1] && lomask[x + 1])) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
	}
	
	/* Test the BOTTOM row of pixels in buffer, except corners */
	for (x = rw - 2; x; x--) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if pixel to the right, or to the left, are empty in the inner mask,
			// but filled in the outer mask
			if ((!limask[x - 1] && lomask[x - 1]) || (!limask[x + 1] && lomask[x + 1])) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
	}
	/* Test the LEFT edge of pixels in buffer, except corners */
	for (x = t - (rw << 1) + 1; x >= rw; x -= rw) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if pixel underneath, or above, are empty in the inner mask,
			// but filled in the outer mask
			if ((!limask[x - rw] && lomask[x - rw]) || (!limask[x + rw] && lomask[x + rw])) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
	}
	
	/* Test the RIGHT edge of pixels in buffer, except corners */
	for (x = t - rw; x > rw; x -= rw) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if pixel underneath, or above, are empty in the inner mask,
			// but filled in the outer mask
			if ((!limask[x - rw] && lomask[x - rw]) || (!limask[x + rw] && lomask[x + rw])) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
	}
	
	rsize[0] = isz;  // fill in our return sizes for edges + fill
	rsize[1] = osz;
	rsize[2] = gsz;
}

static void do_adjacentBleedBorders(unsigned int t, unsigned int rw, unsigned int *limask, unsigned int *lomask, unsigned int *lres, float *res, unsigned int *rsize)
{
	int x;
	unsigned int isz = 0; // inner edge size
	unsigned int osz = 0; // outer edge size
	unsigned int gsz = 0; // gradient fill area size
	/* Test the four corners */
	/* upper left corner */
	x = t - rw + 1;
	// test if inner mask is filled
	if (limask[x]) {
		// test if pixel underneath, or to the right, are empty in the inner mask,
		// but filled in the outer mask
		if ((!limask[x - rw] && lomask[x - rw]) || (!limask[x + 1] && lomask[x + 1])) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		if (!lomask[x - rw] || !lomask[x + 1]) { // test if outer mask is empty underneath or to the right
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
		else {
			gsz++;                               // increment the gradient pixel count
			lres[x] = 2;                         // flag pixel as gradient
		}
	}
	/* upper right corner */
	x = t;
	// test if inner mask is filled
	if (limask[x]) {
		// test if pixel underneath, or to the left, are empty in the inner mask,
		// but filled in the outer mask
		if ((!limask[x - rw] && lomask[x - rw]) || (!limask[x - 1] && lomask[x - 1])) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		if (!lomask[x - rw] || !lomask[x - 1]) { // test if outer mask is empty underneath or to the left
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
		else {
			gsz++;                               // increment the gradient pixel count
			lres[x] = 2;                         // flag pixel as gradient
		}
	}
	/* lower left corner */
	x = 0;
	// test if inner mask is filled
	if (limask[x]) {
		// test if pixel above, or to the right, are empty in the inner mask,
		// but filled in the outer mask
		if ((!limask[x + rw] && lomask[x + rw]) || (!limask[x + 1] && lomask[x + 1])) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		if (!lomask[x + rw] || !lomask[x + 1]) { // test if outer mask is empty above or to the right
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
		else {
			gsz++;                               // increment the gradient pixel count
			lres[x] = 2;                         // flag pixel as gradient
		}
	}
	/* lower right corner */
	x = rw - 1;
	// test if inner mask is filled
	if (limask[x]) {
		// test if pixel above, or to the left, are empty in the inner mask,
		// but filled in the outer mask
		if ((!limask[x + rw] && lomask[x + rw]) || (!limask[x - 1] && lomask[x - 1])) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		if (!lomask[x + rw] || !lomask[x - 1]) { // test if outer mask is empty above or to the left
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
		else {
			gsz++;                               // increment the gradient pixel count
			lres[x] = 2;                         // flag pixel as gradient
		}
	}
	/* Test the TOP row of pixels in buffer, except corners */
	for (x = t - 1; x >= (t - rw) + 2; x--) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if pixel to the left, or to the right, are empty in the inner mask,
			// but filled in the outer mask
			if ((!limask[x - 1] && lomask[x - 1]) || (!limask[x + 1] && lomask[x + 1])) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			if (!lomask[x - 1] || !lomask[x + 1]) {   // test if outer mask is empty to the left or to the right
				osz++;                           // increment outer edge size
				lres[x] = 3;                     // flag pixel as outer edge
			}
			else {
				gsz++;                           // increment the gradient pixel count
				lres[x] = 2;                     // flag pixel as gradient
			}
		}
	}
	
	/* Test the BOTTOM row of pixels in buffer, except corners */
	for (x = rw - 2; x; x--) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if pixel to the left, or to the right, are empty in the inner mask,
			// but filled in the outer mask
			if ((!limask[x - 1] && lomask[x - 1]) || (!limask[x + 1] && lomask[x + 1])) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                     // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			if (!lomask[x - 1] || !lomask[x + 1]) { // test if outer mask is empty to the left or to the right
				osz++;                           // increment outer edge size
				lres[x] = 3;                     // flag pixel as outer edge
			}
			else {
				gsz++;                           // increment the gradient pixel count
				lres[x] = 2;                     // flag pixel as gradient
			}
		}
	}
	/* Test the LEFT edge of pixels in buffer, except corners */
	for (x = t - (rw << 1) + 1; x >= rw; x -= rw) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if pixel underneath, or above, are empty in the inner mask,
			// but filled in the outer mask
			if ((!limask[x - rw] && lomask[x - rw]) || (!limask[x + rw] && lomask[x + rw])) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			if (!lomask[x - rw] || !lomask[x + rw]) { // test if outer mask is empty underneath or above
				osz++;                           // increment outer edge size
				lres[x] = 3;                     // flag pixel as outer edge
			}
			else {
				gsz++;                           // increment the gradient pixel count
				lres[x] = 2;                     // flag pixel as gradient
			}
		}
	}
	
	/* Test the RIGHT edge of pixels in buffer, except corners */
	for (x = t - rw; x > rw; x -= rw) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if pixel underneath, or above, are empty in the inner mask,
			// but filled in the outer mask
			if ((!limask[x - rw] && lomask[x - rw]) || (!limask[x + rw] && lomask[x + rw])) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			if (!lomask[x - rw] || !lomask[x + rw]) { // test if outer mask is empty underneath or above
				osz++;                           // increment outer edge size
				lres[x] = 3;                     // flag pixel as outer edge
			}
			else {
				gsz++;                           // increment the gradient pixel count
				lres[x] = 2;                     // flag pixel as gradient
			}
		}
	}
	
	rsize[0] = isz;  // fill in our return sizes for edges + fill
	rsize[1] = osz;
	rsize[2] = gsz;
}

static void do_allKeepBorders(unsigned int t, unsigned int rw, unsigned int *limask, unsigned int *lomask, unsigned int *lres, float *res, unsigned int *rsize)
{
	int x;
	unsigned int isz = 0; // inner edge size
	unsigned int osz = 0; // outer edge size
	unsigned int gsz = 0; // gradient fill area size
	/* Test the four corners */
	/* upper left corner */
	x = t - rw + 1;
	// test if inner mask is filled
	if (limask[x]) {
		// test if the inner mask is empty underneath or to the right
		if (!limask[x - rw] || !limask[x + 1]) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		osz++;                                   // increment outer edge size
		lres[x] = 3;                             // flag pixel as outer edge
	}
	/* upper right corner */
	x = t;
	// test if inner mask is filled
	if (limask[x]) {
		// test if the inner mask is empty underneath or to the left
		if (!limask[x - rw] || !limask[x - 1]) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		osz++;                                   // increment outer edge size
		lres[x] = 3;                             // flag pixel as outer edge
	}
	/* lower left corner */
	x = 0;
	// test if inner mask is filled
	if (limask[x]) {
		// test if inner mask is empty above or to the right
		if (!limask[x + rw] || !limask[x + 1]) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		osz++;                                   // increment outer edge size
		lres[x] = 3;                             // flag pixel as outer edge
	}
	/* lower right corner */
	x = rw - 1;
	// test if inner mask is filled
	if (limask[x]) {
		// test if inner mask is empty above or to the left
		if (!limask[x + rw] || !limask[x - 1]) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		osz++;                                   // increment outer edge size
		lres[x] = 3;                             // flag pixel as outer edge
	}
	
	/* Test the TOP row of pixels in buffer, except corners */
	for (x = t - 1; x >= (t - rw) + 2; x--) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if inner mask is empty to the left or to the right
			if (!limask[x - 1] || !limask[x + 1]) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
	}
	
	/* Test the BOTTOM row of pixels in buffer, except corners */
	for (x = rw - 2; x; x--) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if inner mask is empty to the left or to the right
			if (!limask[x - 1] || !limask[x + 1]) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
	}
	/* Test the LEFT edge of pixels in buffer, except corners */
	for (x = t - (rw << 1) + 1; x >= rw; x -= rw) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if inner mask is empty underneath or above
			if (!limask[x - rw] || !limask[x + rw]) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
	}
	
	/* Test the RIGHT edge of pixels in buffer, except corners */
	for (x = t - rw; x > rw; x -= rw) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if inner mask is empty underneath or above
			if (!limask[x - rw] || !limask[x + rw]) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
	}
	
	rsize[0] = isz;  // fill in our return sizes for edges + fill
	rsize[1] = osz;
	rsize[2] = gsz;
}

static void do_allBleedBorders(unsigned int t, unsigned int rw, unsigned int *limask, unsigned int *lomask, unsigned int *lres, float *res, unsigned int *rsize)
{
	int x;
	unsigned int isz = 0; // inner edge size
	unsigned int osz = 0; // outer edge size
	unsigned int gsz = 0; // gradient fill area size
	/* Test the four corners */
	/* upper left corner */
	x = t - rw + 1;
	// test if inner mask is filled
	if (limask[x]) {
		// test if the inner mask is empty underneath or to the right
		if (!limask[x - rw] || !limask[x + 1]) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		if (!lomask[x - rw] || !lomask[x + 1]) { // test if outer mask is empty underneath or to the right
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
		else {
			gsz++;                               // increment the gradient pixel count
			lres[x] = 2;                         // flag pixel as gradient
		}
	}
	/* upper right corner */
	x = t;
	// test if inner mask is filled
	if (limask[x]) {
		// test if the inner mask is empty underneath or to the left
		if (!limask[x - rw] || !limask[x - 1]) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		if (!lomask[x - rw] || !lomask[x - 1]) { // test if outer mask is empty above or to the left
			osz++;                               // increment outer edge size
			lres[x] = 3;                           // flag pixel as outer edge
		}
		else {
			gsz++;                               // increment the gradient pixel count
			lres[x] = 2;                         // flag pixel as gradient
		}
	}
	/* lower left corner */
	x = 0;
	// test if inner mask is filled
	if (limask[x]) {
		// test if inner mask is empty above or to the right
		if (!limask[x + rw] || !limask[x + 1]) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		if (!lomask[x + rw] || !lomask[x + 1]) { // test if outer mask is empty underneath or to the right
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
		else {
			gsz++;                               // increment the gradient pixel count
			lres[x] = 2;                         // flag pixel as gradient
		}
	}
	/* lower right corner */
	x = rw - 1;
	// test if inner mask is filled
	if (limask[x]) {
		// test if inner mask is empty above or to the left
		if (!limask[x + rw] || !limask[x - 1]) {
			isz++;                               // increment inner edge size
			lres[x] = 4;                         // flag pixel as inner edge
		}
		else {
			res[x] = 1.0f;                       // pixel is just part of inner mask, and it's not an edge
		}
	}
	else if (lomask[x]) {                        // inner mask was empty, test if outer mask is filled
		if (!lomask[x + rw] || !lomask[x - 1]) { // test if outer mask is empty underneath or to the left
			osz++;                               // increment outer edge size
			lres[x] = 3;                         // flag pixel as outer edge
		}
		else {
			gsz++;                               // increment the gradient pixel count
			lres[x] = 2;                         // flag pixel as gradient
		}
	}
	/* Test the TOP row of pixels in buffer, except corners */
	for (x = t - 1; x >= (t - rw) + 2; x--) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if inner mask is empty to the left or to the right
			if (!limask[x - 1] || !limask[x + 1]) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			if (!lomask[x - 1] || !lomask[x + 1]) { // test if outer mask is empty to the left or to the right
				osz++;                           // increment outer edge size
				lres[x] = 3;                     // flag pixel as outer edge
			}
			else {
				gsz++;                           // increment the gradient pixel count
				lres[x] = 2;                     // flag pixel as gradient
			}
		}
	}
	
	/* Test the BOTTOM row of pixels in buffer, except corners */
	for (x = rw - 2; x; x--) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if inner mask is empty to the left or to the right
			if (!limask[x - 1] || !limask[x + 1]) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			if (!lomask[x - 1] || !lomask[x + 1]) {   // test if outer mask is empty to the left or to the right
				osz++;                           // increment outer edge size
				lres[x] = 3;                     // flag pixel as outer edge
			}
			else {
				gsz++;                           // increment the gradient pixel count
				lres[x] = 2;                     // flag pixel as gradient
			}
		}
	}
	/* Test the LEFT edge of pixels in buffer, except corners */
	for (x = t - (rw << 1) + 1; x >= rw; x -= rw) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if inner mask is empty underneath or above
			if (!limask[x - rw] || !limask[x + rw]) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                   // inner mask was empty, test if outer mask is filled
			if (!lomask[x - rw] || !lomask[x + rw]) { // test if outer mask is empty underneath or above
				osz++;                           // increment outer edge size
				lres[x] = 3;                     // flag pixel as outer edge
			}
			else {
				gsz++;                           // increment the gradient pixel count
				lres[x] = 2;                     // flag pixel as gradient
			}
		}
	}
	
	/* Test the RIGHT edge of pixels in buffer, except corners */
	for (x = t - rw; x > rw; x -= rw) {
		// test if inner mask is filled
		if (limask[x]) {
			// test if inner mask is empty underneath or above
			if (!limask[x - rw] || !limask[x + rw]) {
				isz++;                           // increment inner edge size
				lres[x] = 4;                     // flag pixel as inner edge
			}
			else {
				res[x] = 1.0f;                   // pixel is just part of inner mask, and it's not an edge
			}
		}
		else if (lomask[x]) {                    // inner mask was empty, test if outer mask is filled
			if (!lomask[x - rw] || !lomask[x + rw]) { // test if outer mask is empty underneath or above
				osz++;                           // increment outer edge size
				lres[x] = 3;                     // flag pixel as outer edge
			}
			else {
				gsz++;                           // increment the gradient pixel count
				lres[x] = 2;                     // flag pixel as gradient
			}
		}
	}
	
	rsize[0] = isz;  // fill in our return sizes for edges + fill
	rsize[1] = osz;
	rsize[2] = gsz;
}

static void do_allEdgeDetection(unsigned int t, unsigned int rw, unsigned int *limask, unsigned int *lomask, unsigned int *lres, float *res, unsigned int *rsize, unsigned int in_isz, unsigned int in_osz, unsigned int in_gsz)
{
	int x;                             // x = pixel loop counter
	int a;                             // a = pixel loop counter
	int dx;                            // dx = delta x
	int pix_prevRow;                   // pix_prevRow = pixel one row behind the one we are testing in a loop
	int pix_nextRow;                   // pix_nextRow = pixel one row in front of the one we are testing in a loop
	int pix_prevCol;                   // pix_prevCol = pixel one column behind the one we are testing in a loop
	int pix_nextCol;                   // pix_nextCol = pixel one column in front of the one we are testing in a loop
	/* Test all rows between the FIRST and LAST rows, excluding left and right edges */
	for (x = (t - rw) + 1, dx = x - (rw - 2); dx > rw; x -= rw, dx -= rw) {
		a = x - 2;
		pix_prevRow = a + rw;
		pix_nextRow = a - rw;
		pix_prevCol = a + 1;
		pix_nextCol = a - 1;
		while (a > dx - 2) {
			if (!limask[a]) {             // if the inner mask is empty
				if (lomask[a]) {          // if the outer mask is full
					/*
					 * Next we test all 4 directions around the current pixel: next/prev/up/down
					 * The test ensures that the outer mask is empty and that the inner mask
					 * is also empty. If both conditions are true for any one of the 4 adjacent pixels
					 * then the current pixel is counted as being a true outer edge pixel.
					 */
					if ((!lomask[pix_nextCol] && !limask[pix_nextCol]) ||
					    (!lomask[pix_prevCol] && !limask[pix_prevCol]) ||
					    (!lomask[pix_nextRow] && !limask[pix_nextRow]) ||
					    (!lomask[pix_prevRow] && !limask[pix_prevRow]))
					{
						in_osz++;                // increment the outer boundary pixel count
						lres[a] = 3;             // flag pixel as part of outer edge
					}
					else {                       // it's not a boundary pixel, but it is a gradient pixel
						in_gsz++;                // increment the gradient pixel count
						lres[a] = 2;             // flag pixel as gradient
					}
				}
				
			}
			else {
				if (!limask[pix_nextCol] || !limask[pix_prevCol] || !limask[pix_nextRow] || !limask[pix_prevRow]) {
					in_isz++;                    // increment the inner boundary pixel count
					lres[a] = 4;                 // flag pixel as part of inner edge
				}
				else {
					res[a] = 1.0f;               // pixel is part of inner mask, but not at an edge
				}
			}
			a--;
			pix_prevRow--;
			pix_nextRow--;
			pix_prevCol--;
			pix_nextCol--;
		}
	}
	
	rsize[0] = in_isz;  // fill in our return sizes for edges + fill
	rsize[1] = in_osz;
	rsize[2] = in_gsz;
}

static void do_adjacentEdgeDetection(unsigned int t, unsigned int rw, unsigned int *limask, unsigned int *lomask, unsigned int *lres, float *res, unsigned int *rsize, unsigned int in_isz, unsigned int in_osz, unsigned int in_gsz)
{
	int x;                             // x = pixel loop counter
	int a;                             // a = pixel loop counter
	int dx;                            // dx = delta x
	int pix_prevRow;                   // pix_prevRow = pixel one row behind the one we are testing in a loop
	int pix_nextRow;                   // pix_nextRow = pixel one row in front of the one we are testing in a loop
	int pix_prevCol;                   // pix_prevCol = pixel one column behind the one we are testing in a loop
	int pix_nextCol;                   // pix_nextCol = pixel one column in front of the one we are testing in a loop
	/* Test all rows between the FIRST and LAST rows, excluding left and right edges */
	for (x = (t - rw) + 1, dx = x - (rw - 2); dx > rw; x -= rw, dx -= rw) {
		a = x - 2;
		pix_prevRow = a + rw;
		pix_nextRow = a - rw;
		pix_prevCol = a + 1;
		pix_nextCol = a - 1;
		while (a > dx - 2) {
			if (!limask[a]) {                    // if the inner mask is empty
				if (lomask[a]) {                 // if the outer mask is full
					/*
					 * Next we test all 4 directions around the current pixel: next/prev/up/down
					 * The test ensures that the outer mask is empty and that the inner mask
					 * is also empty. If both conditions are true for any one of the 4 adjacent pixels
					 * then the current pixel is counted as being a true outer edge pixel.
					 */
					if ((!lomask[pix_nextCol] && !limask[pix_nextCol]) ||
					    (!lomask[pix_prevCol] && !limask[pix_prevCol]) ||
					    (!lomask[pix_nextRow] && !limask[pix_nextRow]) ||
					    (!lomask[pix_prevRow] && !limask[pix_prevRow]))
					{
						in_osz++;                // increment the outer boundary pixel count
						lres[a] = 3;             // flag pixel as part of outer edge
					}
					else {                       // it's not a boundary pixel, but it is a gradient pixel
						in_gsz++;                // increment the gradient pixel count
						lres[a] = 2;             // flag pixel as gradient
					}
				}
				
			}
			else {
				if ((!limask[pix_nextCol] && lomask[pix_nextCol]) ||
				    (!limask[pix_prevCol] && lomask[pix_prevCol]) ||
				    (!limask[pix_nextRow] && lomask[pix_nextRow]) ||
				    (!limask[pix_prevRow] && lomask[pix_prevRow]))
				{
					in_isz++;                    // increment the inner boundary pixel count
					lres[a] = 4;                 // flag pixel as part of inner edge
				}
				else {
					res[a] = 1.0f;               // pixel is part of inner mask, but not at an edge
				}
			}
			a--;
			pix_prevRow--;                       // advance all four "surrounding" pixel pointers
			pix_nextRow--;
			pix_prevCol--;
			pix_nextCol--;
		}
	}
	
	rsize[0] = in_isz;  // fill in our return sizes for edges + fill
	rsize[1] = in_osz;
	rsize[2] = in_gsz;
}

static void do_createEdgeLocationBuffer(unsigned int t, unsigned int rw, unsigned int *lres, float *res, unsigned short *gbuf, unsigned int *innerEdgeOffset, unsigned int *outerEdgeOffset, unsigned int isz, unsigned int gsz)
{
	int x;                             // x = pixel loop counter
	int a;                             // a = temporary pixel index buffer loop counter
	unsigned int ud;                   // ud = unscaled edge distance
	unsigned int dmin;                 // dmin = minimum edge distance
	
	unsigned int rsl;                  // long used for finding fast 1.0/sqrt
	unsigned int gradientFillOffset;
	unsigned int innerAccum = 0;       // for looping inner edge pixel indexes, represents current position from offset
	unsigned int outerAccum = 0;       // for looping outer edge pixel indexes, represents current position from offset
	unsigned int gradientAccum = 0;    // for looping gradient pixel indexes, represents current position from offset
	/*
	 * Here we compute the size of buffer needed to hold (row,col) coordinates
	 * for each pixel previously determined to be either gradient, inner edge,
	 * or outer edge.
	 *
	 * Allocation is done by requesting 4 bytes "sizeof(int)" per pixel, even
	 * though gbuf[] is declared as (unsigned short *) (2 bytes) because we don't
	 * store the pixel indexes, we only store x,y location of pixel in buffer.
	 *
	 * This does make the assumption that x and y can fit in 16 unsigned bits
	 * so if Blender starts doing renders greater than 65536 in either direction
	 * this will need to allocate gbuf[] as unsigned int *and allocate 8 bytes
	 * per flagged pixel.
	 *
	 * In general, the buffer on-screen:
	 *
	 * Example:  9 by 9 pixel block
	 *
	 * . = pixel non-white in both outer and inner mask
	 * o = pixel white in outer, but not inner mask, adjacent to "." pixel
	 * g = pixel white in outer, but not inner mask, not adjacent to "." pixel
	 * i = pixel white in inner mask, adjacent to "g" or "." pixel
	 * F = pixel white in inner mask, only adjacent to other pixels white in the inner mask
	 *
	 *
	 * .........   <----- pixel #80
	 * ..oooo...
	 * .oggggo..
	 * .oggiggo.
	 * .ogiFigo.
	 * .oggiggo.
	 * .oggggo..
	 * ..oooo...
	 * pixel #00 -----> .........
	 *
	 * gsz = 18   (18 "g" pixels above)
	 * isz = 4    (4 "i" pixels above)
	 * osz = 18   (18 "o" pixels above)
	 *
	 *
	 * The memory in gbuf[] after filling will look like this:
	 *
	 * gradientFillOffset (0 pixels)                   innerEdgeOffset (18 pixels)    outerEdgeOffset (22 pixels)
	 * /                                               /                              /
	 * /                                               /                              /
	 * |X   Y   X   Y   X   Y   X   Y   >     <X   Y   X   Y   >     <X   Y   X   Y   X   Y   >     <X   Y   X   Y   | <- (x,y)
	 * +-------------------------------->     <---------------->     <------------------------>     <----------------+
	 * |0   2   4   6   8   10  12  14  > ... <68  70  72  74  > ... <80  82  84  86  88  90  > ... <152 154 156 158 | <- bytes
	 * +-------------------------------->     <---------------->     <------------------------>     <----------------+
	 * |g0  g0  g1  g1  g2  g2  g3  g3  >     <g17 g17 i0  i0  >     <i2  i2  i3  i3  o0  o0  >     <o16 o16 o17 o17 | <- pixel
	 *       /                              /                              /
	 *      /                              /                              /
	 *        /                              /                              /
	 * +---------- gradientAccum (18) ---------+      +--- innerAccum (22) ---+      +--- outerAccum (40) ---+
	 *
	 *
	 * Ultimately we do need the pixel's memory buffer index to set the output
	 * pixel color, but it's faster to reconstruct the memory buffer location
	 * each iteration of the final gradient calculation than it is to deconstruct
	 * a memory location into x,y pairs each round.
	 */


	gradientFillOffset = 0;                            // since there are likely "more" of these, put it first. :)
	*innerEdgeOffset = gradientFillOffset + gsz;       // set start of inner edge indexes
	*outerEdgeOffset = (*innerEdgeOffset) + isz;       // set start of outer edge indexes
	/* set the accumulators to correct positions */    // set up some accumulator variables for loops
	gradientAccum = gradientFillOffset;                // each accumulator variable starts at its respective
	innerAccum = *innerEdgeOffset;                     // section's offset so when we start filling, each
	outerAccum = *outerEdgeOffset;                     // section fills up it's allocated space in gbuf
	//uses dmin=row, rsl=col
	for (x = 0, dmin = 0; x < t; x += rw, dmin++) {
		for (rsl = 0; rsl < rw; rsl++) {
			a = x + rsl;
			if (lres[a] == 2) {                  // it is a gradient pixel flagged by 2
				ud = gradientAccum << 1;         // double the index to reach correct unsigned short location
				gbuf[ud] = dmin;                 // insert pixel's row into gradient pixel location buffer
				gbuf[ud + 1] = rsl;              // insert pixel's column into gradient pixel location buffer
				gradientAccum++;                 // increment gradient index buffer pointer
			}
			else if (lres[a] == 3) {             // it is an outer edge pixel flagged by 3
				ud = outerAccum << 1;            // double the index to reach correct unsigned short location
				gbuf[ud] = dmin;                 // insert pixel's row into outer edge pixel location buffer
				gbuf[ud + 1] = rsl;              // insert pixel's column into outer edge pixel location buffer
				outerAccum++;                    // increment outer edge index buffer pointer
				res[a] = 0.0f;                   // set output pixel intensity now since it won't change later
			}
			else if (lres[a] == 4) {             // it is an inner edge pixel flagged by 4
				ud = innerAccum << 1;            // double int index to reach correct unsigned short location
				gbuf[ud] = dmin;                 // insert pixel's row into inner edge pixel location buffer
				gbuf[ud + 1] = rsl;              // insert pixel's column into inner edge pixel location buffer
				innerAccum++;                    // increment inner edge index buffer pointer
				res[a] = 1.0f;                   // set output pixel intensity now since it won't change later
			}
		}
	}
	
}

static void do_fillGradientBuffer(unsigned int rw, float *res, unsigned short *gbuf, unsigned int isz, unsigned int osz, unsigned int gsz, unsigned int innerEdgeOffset, unsigned int outerEdgeOffset)
{
	int x;                             // x = pixel loop counter
	int a;                             // a = temporary pixel index buffer loop counter
	int fsz;                           // size of the frame
	unsigned int rsl;                  // long used for finding fast 1.0/sqrt
	float rsf;                         // float used for finding fast 1.0/sqrt
	const float rsopf = 1.5f;          // constant float used for finding fast 1.0/sqrt
	
	unsigned int gradientFillOffset;
	unsigned int t;
	unsigned int ud;                   // ud = unscaled edge distance
	unsigned int dmin;                 // dmin = minimum edge distance
	float odist;                       // odist = current outer edge distance
	float idist;                       // idist = current inner edge distance
	int dx;                            // dx = X-delta (used for distance proportion calculation)
	int dy;                            // dy = Y-delta (used for distance proportion calculation)
	
	/*
	 * The general algorithm used to color each gradient pixel is:
	 *
	 * 1.) Loop through all gradient pixels.
	 * A.) For each gradient pixel:
	 * a.) Loop though all outside edge pixels, looking for closest one
	 * to the gradient pixel we are in.
	 * b.) Loop through all inside edge pixels, looking for closest one
	 * to the gradient pixel we are in.
	 * c.) Find proportion of distance from gradient pixel to inside edge
	 * pixel compared to sum of distance to inside edge and distance to
	 * outside edge.
	 *
	 * In an image where:
	 * . = blank (black) pixels, not covered by inner mask or outer mask
	 * + = desired gradient pixels, covered only by outer mask
	 * * = white full mask pixels, covered by at least inner mask
	 *
	 * ...............................
	 * ...............+++++++++++.....
	 * ...+O++++++..++++++++++++++....
	 * ..+++\++++++++++++++++++++.....
	 * .+++++G+++++++++*******+++.....
	 * .+++++|+++++++*********+++.....
	 * .++***I****************+++.....
	 * .++*******************+++......
	 * .+++*****************+++.......
	 * ..+++***************+++........
	 * ....+++**********+++...........
	 * ......++++++++++++.............
	 * ...............................
	 *
	 * O = outside edge pixel
	 * \
	 *  G = gradient pixel
	 *  |
	 *  I = inside edge pixel
	 * 
	 *   __
	 *  *note that IO does not need to be a straight line, in fact
	 *  many cases can arise where straight lines do not work
	 *  correctly.
	 *
	 *     __       __     __
	 * d.) Pixel color is assigned as |GO| / ( |GI| + |GO| )
	 *
	 * The implementation does not compute distance, but the reciprocal of the
	 * distance. This is done to avoid having to compute a square root, as a
	 * reciprocal square root can be computed faster. Therefore, the code computes
	 * pixel color as |GI| / (|GI| + |GO|). Since these are reciprocals, GI serves the
	 * purpose of GO for the proportion calculation.
	 *
	 * For the purposes of the minimum distance comparisons, we only check
	 * the sums-of-squares against eachother, since they are in the same
	 * mathematical sort-order as if we did go ahead and take square roots
	 *
	 * Loop through all gradient pixels.
	 */

	for (x = gsz - 1; x >= 0; x--) {
		gradientFillOffset = x << 1;
		t = gbuf[gradientFillOffset];            // calculate column of pixel indexed by gbuf[x]
		fsz = gbuf[gradientFillOffset + 1];      // calculate row of pixel indexed by gbuf[x]
		dmin = 0xffffffff;                       // reset min distance to edge pixel
		for (a = outerEdgeOffset + osz - 1; a >= outerEdgeOffset; a--) {   // loop through all outer edge buffer pixels
			ud = a << 1;
			dy = t - gbuf[ud];                   // set dx to gradient pixel column - outer edge pixel row
			dx = fsz - gbuf[ud + 1];             // set dy to gradient pixel row - outer edge pixel column
			ud = dx * dx + dy * dy;              // compute sum of squares
			if (ud < dmin) {                     // if our new sum of squares is less than the current minimum
				dmin = ud;                       // set a new minimum equal to the new lower value
			}
		}
		odist = (float)(dmin);                   // cast outer min to a float
		rsf = odist * 0.5f;                      //
		rsl = *(unsigned int *)&odist;           // use some peculiar properties of the way bits are stored
		rsl = 0x5f3759df - (rsl >> 1);           // in floats vs. unsigned ints to compute an approximate
		odist = *(float *)&rsl;                  // reciprocal square root
		odist = odist * (rsopf - (rsf * odist * odist));   // -- ** this line can be iterated for more accuracy ** --
		dmin = 0xffffffff;                       // reset min distance to edge pixel
		for (a = innerEdgeOffset + isz - 1; a >= innerEdgeOffset; a--) {   // loop through all inside edge pixels
			ud = a << 1;
			dy = t - gbuf[ud];         // compute delta in Y from gradient pixel to inside edge pixel
			dx = fsz - gbuf[ud + 1];     // compute delta in X from gradient pixel to inside edge pixel
			ud = dx * dx + dy * dy;        // compute sum of squares
			if (ud < dmin) {          // if our new sum of squares is less than the current minimum we've found
				dmin = ud;           // set a new minimum equal to the new lower value
			}
		}
		idist = (float)(dmin);                   // cast inner min to a float
		rsf = idist * 0.5f;                      //
		rsl = *(unsigned int *)&idist;           //
		rsl = 0x5f3759df - (rsl >> 1);           // see notes above
		idist = *(float *)&rsl;                  //
		idist = idist * (rsopf - (rsf * idist * idist));   //
		/*
		 * Note once again that since we are using reciprocals of distance values our
		 * proportion is already the correct intensity, and does not need to be
		 * subtracted from 1.0 like it would have if we used real distances.
		 */
		
		/*
		 * Here we reconstruct the pixel's memory location in the CompBuf by
		 * Pixel Index = Pixel Column + ( Pixel Row * Row Width )
		 */
		res[gbuf[gradientFillOffset + 1] + (gbuf[gradientFillOffset] * rw)] = (idist / (idist + odist));    //set intensity
	}
	
}

// end of copy

void DoubleEdgeMaskOperation::doDoubleEdgeMask(float *imask, float *omask, float *res)
{
	unsigned int *lres;                // lres = unsigned int pointer to output pixel buffer (for bit operations)
	unsigned int *limask;              // limask = unsigned int pointer to inner mask (for bit operations)
	unsigned int *lomask;              // lomask = unsigned int pointer to outer mask (for bit operations)
	
	int rw;                            // rw = pixel row width
	int t;                             // t = total number of pixels in buffer - 1 (used for loop starts)
	int fsz;                           // size of the frame
	
	unsigned int isz = 0;                // size (in pixels) of inside edge pixel index buffer
	unsigned int osz = 0;                // size (in pixels) of outside edge pixel index buffer
	unsigned int gsz = 0;                // size (in pixels) of gradient pixel index buffer
	unsigned int rsize[3];               // size storage to pass to helper functions
	unsigned int innerEdgeOffset = 0;    // offset into final buffer where inner edge pixel indexes start
	unsigned int outerEdgeOffset = 0;    // offset into final buffer where outer edge pixel indexes start
	
	unsigned short *gbuf;              // gradient/inner/outer pixel location index buffer
	
	if (true) {                    // if both input sockets have some data coming in...
		
		t = (this->getWidth() * this->getHeight()) - 1;                                // determine size of the frame
		
		lres = (unsigned int *)res;      // unsigned int pointer to output buffer (for bit level ops)
		limask = (unsigned int *)imask;   // unsigned int pointer to input mask (for bit level ops)
		lomask = (unsigned int *)omask;   // unsigned int pointer to output mask (for bit level ops)
		rw = this->getWidth();                   // width of a row of pixels
		
		
		/*
		 * The whole buffer is broken up into 4 parts. The four CORNERS, the FIRST and LAST rows, the
		 * LEFT and RIGHT edges (excluding the corner pixels), and all OTHER rows.
		 * This allows for quick computation of outer edge pixels where
		 * a screen edge pixel is marked to be gradient.
		 *
		 * The pixel type (gradient vs inner-edge vs outer-edge) tests change
		 * depending on the user selected "Inner Edge Mode" and the user selected
		 * "Buffer Edge Mode" on the node's GUI. There are 4 sets of basically the
		 * same algorithm:
		 *
		 * 1.) Inner Edge -> Adjacent Only
		 *   Buffer Edge -> Keep Inside
		 *
		 * 2.) Inner Edge -> Adjacent Only
		 *   Buffer Edge -> Bleed Out
		 *
		 * 3.) Inner Edge -> All
		 *   Buffer Edge -> Keep Inside
		 *
		 * 4.) Inner Edge -> All
		 *   Buffer Edge -> Bleed Out
		 *
		 * Each version has slightly different criteria for detecting an edge pixel.
		 */
		if (this->m_adjecentOnly) {              // if "adjacent only" inner edge mode is turned on
			if (this->m_keepInside) {            // if "keep inside" buffer edge mode is turned on
				do_adjacentKeepBorders(t, rw, limask, lomask, lres, res, rsize);
			}
			else {                               // "bleed out" buffer edge mode is turned on
				do_adjacentBleedBorders(t, rw, limask, lomask, lres, res, rsize);
			}
			isz = rsize[0];                      // set up inner edge, outer edge, and gradient buffer sizes after border pass
			osz = rsize[1];
			gsz = rsize[2];
			// detect edges in all non-border pixels in the buffer
			do_adjacentEdgeDetection(t, rw, limask, lomask, lres, res, rsize, isz, osz, gsz);
		}
		else {                                   // "all" inner edge mode is turned on
			if (this->m_keepInside) {              // if "keep inside" buffer edge mode is turned on
				do_allKeepBorders(t, rw, limask, lomask, lres, res, rsize);
			}
			else {                               // "bleed out" buffer edge mode is turned on
				do_allBleedBorders(t, rw, limask, lomask, lres, res, rsize);
			}
			isz = rsize[0];                      // set up inner edge, outer edge, and gradient buffer sizes after border pass
			osz = rsize[1];
			gsz = rsize[2];
			// detect edges in all non-border pixels in the buffer
			do_allEdgeDetection(t, rw, limask, lomask, lres, res, rsize, isz, osz, gsz);
		}
		
		isz = rsize[0];                          // set edge and gradient buffer sizes once again...
		osz = rsize[1];                          // the sizes in rsize[] may have been modified
		gsz = rsize[2];                          // by the do_*EdgeDetection() function.
		
		fsz = gsz + isz + osz;                                   // calculate size of pixel index buffer needed
		gbuf = (unsigned short *)MEM_callocN(sizeof(unsigned short) * fsz * 2, "DEM"); // allocate edge/gradient pixel index buffer
		
		do_createEdgeLocationBuffer(t, rw, lres, res, gbuf, &innerEdgeOffset, &outerEdgeOffset, isz, gsz);
		do_fillGradientBuffer(rw, res, gbuf, isz, osz, gsz, innerEdgeOffset, outerEdgeOffset);
		
		MEM_freeN(gbuf);                         // free the gradient index buffer
	}
}

DoubleEdgeMaskOperation::DoubleEdgeMaskOperation() : NodeOperation()
{
	this->addInputSocket(COM_DT_VALUE);
	this->addInputSocket(COM_DT_VALUE);
	this->addOutputSocket(COM_DT_VALUE);
	this->m_inputInnerMask = NULL;
	this->m_inputOuterMask = NULL;
	this->m_adjecentOnly = false;
	this->m_keepInside = false;
	this->setComplex(true);
}

bool DoubleEdgeMaskOperation::determineDependingAreaOfInterest(rcti * /*input*/, ReadBufferOperation *readOperation, rcti *output)
{
	if (this->m_cachedInstance == NULL) {
		rcti newInput;
		newInput.xmax = this->getWidth();
		newInput.xmin = 0;
		newInput.ymax = this->getHeight();
		newInput.ymin = 0;
		return NodeOperation::determineDependingAreaOfInterest(&newInput, readOperation, output);
	}
	else {
		return false;
	}
}

void DoubleEdgeMaskOperation::initExecution()
{
	this->m_inputInnerMask = this->getInputSocketReader(0);
	this->m_inputOuterMask = this->getInputSocketReader(1);
	initMutex();
	this->m_cachedInstance = NULL;
}

void *DoubleEdgeMaskOperation::initializeTileData(rcti *rect)
{
	if (this->m_cachedInstance)
		return this->m_cachedInstance;
	
	lockMutex();
	if (this->m_cachedInstance == NULL) {
		MemoryBuffer *innerMask = (MemoryBuffer *)this->m_inputInnerMask->initializeTileData(rect);
		MemoryBuffer *outerMask = (MemoryBuffer *)this->m_inputOuterMask->initializeTileData(rect);
		float *data = (float *)MEM_mallocN(sizeof(float) * this->getWidth() * this->getHeight(), __func__);
		float *imask = innerMask->getBuffer();
		float *omask = outerMask->getBuffer();
		doDoubleEdgeMask(imask, omask, data);
		this->m_cachedInstance = data;
	}
	unlockMutex();
	return this->m_cachedInstance;
}
void DoubleEdgeMaskOperation::executePixel(float output[4], int x, int y, void *data)
{
	float *buffer = (float *)data;
	int index = (y * this->getWidth() + x);
	output[0] = buffer[index];
}

void DoubleEdgeMaskOperation::deinitExecution()
{
	this->m_inputInnerMask = NULL;
	this->m_inputOuterMask = NULL;
	deinitMutex();
	if (this->m_cachedInstance) {
		MEM_freeN(this->m_cachedInstance);
		this->m_cachedInstance = NULL;
	}
}