clld.c   | 185 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------------------
 test-ppx |  56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 221 insertions(+), 20 deletions(-)

diff --git a/clld.c b/clld.c
index 6d6d3a0..5a9372e 100644
--- a/clld.c
+++ b/clld.c
@@ -16,7 +16,7 @@
 #define max(a, b) (abs(a-b)+(a+b))/2
 #define min(a, b) -max(-a, -b)
 
-enum {THM, AABB};
+enum {THM, AABB, PPX };
 
 /* Collision type */
 int colltype = -1;
@@ -74,8 +74,8 @@ int main(int argc, char **argv) {
 		double d1;
 		double d2;
 
-		/* Heightmap, used in Tile Heightmap collision. */
-		uint8_t *heightmap;
+		/* Bitmask used in Per Pixel, and Tile Heightmap collision. */
+		uint8_t **bitmask;
 
 		/* X axis collision. */
 		unsigned int clx : 1;
@@ -120,10 +120,34 @@ int main(int argc, char **argv) {
 		tmp.w = atoi(strtok(buf, ","));
 		tmp.h = atoi(strtok(NULL, "\n"));
 		/*
-		 * Initialize heightmap.
+		 * Initialize y axis of bitmask.
+		 * If Tile Heightmap is used, Initialize it using the width.
 		 */
-		if (colltype == THM && coll)
-			tmp.heightmap = malloc(sizeof(uint8_t *)*tmp.w);
+		if (colltype == THM || colltype == PPX)
+			tmp.bitmask = (colltype == PPX) ? malloc(sizeof(uint8_t *)*tmp.h) : malloc(sizeof(uint8_t *)*tmp.w);
+		/* Initialize x axis of bitmask. */
+		if (colltype == PPX)
+			for(unsigned int i = 0; i<tmp.h; i++)
+				tmp.bitmask[i] = malloc(sizeof(uint8_t)*tmp.w);
+		/* Get Per Pixel data. */
+		if (colltype == PPX) {
+			for (unsigned int j = 0; j<tmp.h; j++) {
+				buf = NULL;
+				size_t newidth = getline(&buf, &size, stdin);
+				/*
+				 * Format is:
+				 *
+				 * 000111000... Until bit w-1.
+				 * .
+				 * .
+				 *
+				 * Until bit h-1.
+				 */
+				tmp.w = (newidth >= tmp.w) ? tmp.w : newidth;
+				for (unsigned int i = 0; i <tmp.w; i++)
+					tmp.bitmask[j][i] = buf[i] - '0';
+			}
+		}
 		/* Get Tile Heightmap data. */
 		if (colltype == THM && coll) {
 			/* Get vertical flip flag */
@@ -142,25 +166,36 @@ int main(int argc, char **argv) {
 			for (unsigned int i = 0; i <tmp.w; i++) {
 				char *tmptok = strtok((i == 0) ? buf : NULL,",");
 				tmptok = (tmptok == NULL) ? strtok(NULL,"\n") : tmptok;
-				tmp.heightmap[i] = (uint8_t *)((atoi(tmptok) <= tmp.h) ? atoi(tmptok) : tmp.h);
+				tmp.bitmask[i] = (uint8_t *)((atoi(tmptok) <= tmp.h) ? atoi(tmptok) : tmp.h);
 				hmpeak = (atoi(tmptok)+1 >= hmpeak) ? atoi(tmptok)+1 : hmpeak;
 			}
 
 		}
 
 		/*
-		 * Copy width, and height to either
-		 * the Cursor, or the Floor.
+		 * Copy width, height, and bitmask over
+		 * to either the Cursor, or the Floor.
 		 */
 		(coll) ? (floor.w = tmp.w) : (cursor.w = tmp.w);
 		(coll) ? (floor.h = tmp.h) : (cursor.h = tmp.h);
-		if (coll)
-			floor.heightmap = tmp.heightmap;
+		(coll) ? (floor.bitmask = tmp.bitmask) : (cursor.bitmask = tmp.bitmask);
 		/* Debugging stuff. */
 		if (verbose >= 1) {
 			if (colltype == THM && coll)
 				 for (unsigned int i = 0; i<floor.h; i++)
-					 printf((i < floor.h-1 && i % 16 != 0 || i == 0) ? "%u, " : ("%u\n"), floor.heightmap[i]);
+					 printf((i < floor.h-1 && i % 16 != 0 || i == 0) ? "%u, " : ("%u\n"), floor.bitmask[i]);
+
+
+			if (colltype == PPX) {
+				for (unsigned int j = 0; j<((coll) ? floor.h : cursor.h); j++) {
+					for (unsigned int i = 0; i<((coll) ? floor.w : cursor.w); i++)
+						if((coll) ? floor.bitmask[j][i] : cursor.bitmask[j][i])
+							printf("%u", (coll) ? floor.bitmask[j][i] : cursor.bitmask[j][i]);
+						else
+							printf(" ");
+					printf("\n");
+				}
+			}
 		}
 
 
@@ -209,6 +244,113 @@ int main(int argc, char **argv) {
 			cursor.yvel = atof(strtok(NULL, "\n"));
 		}
 
+		/* Per Pixel Collision. */
+		if(colltype == PPX && coll) {
+			if (!flt) {
+				cursor.a1 = cursor.pos.x;
+				cursor.a2 = cursor.pos.x+cursor.w;
+				cursor.b1 = cursor.pos.y;
+				cursor.b2 = cursor.pos.y+cursor.h;
+				floor.a1 = floor.pos.x;
+                                floor.a2 = floor.pos.x+floor.w;
+                                floor.b1 = floor.pos.y;
+                                floor.b2 = floor.pos.y+floor.h;
+
+				cursor.clx = ((cursor.a2 > floor.a1-(int)cursor.xvel-1 && cursor.b2 > floor.b1) && (cursor.a1 < floor.a2-(int)cursor.xvel+1 && cursor.b1 < floor.b2)) ? 1 : 0;
+				cursor.cly = ((cursor.b2 > floor.b1-(int)cursor.yvel-1 && cursor.a2 > floor.a1) && (cursor.b1 < floor.b2-(int)cursor.yvel+1 && cursor.a1 < floor.a2)) ? 1 : 0;
+				cursor.gnded = 0;
+
+				if (cursor.clx || cursor.cly) {
+					int rw1 = (cursor.a2-cursor.a1)/2, rh1 = (cursor.b2-cursor.b1)/2;
+					int rw2 = (floor.a2-floor.a1)/2, rh2 = (floor.b2-floor.b1)/2;
+					uint8_t t = 0, b = 0, l = 0, r = 0;
+					int olxab = min(cursor.a2, floor.a2)-max(cursor.a1, floor.a1);
+					int olyab = min(cursor.b2, floor.b2)-max(cursor.b1, floor.b1);
+					int olxl = cursor.a2-floor.a1;
+					int olxr = floor.a2-cursor.a1;
+					int olyt = cursor.b2-floor.b1;
+					int olyb = floor.b2-cursor.b1;
+					t = (cursor.b2 > rh2 && olyt <= floor.h+1) ? 1 : 0;
+					b = (cursor.b1 > rh2 && olyb <= floor.h+1) ? 1 : 0;
+					l = (cursor.a2 > rw2 && olxl <= floor.w+1) ? 1 : 0;
+					r = (cursor.a1 > rw2 && olxr <= floor.w+1) ? 1 : 0;
+					if (t && b && cursor.xvel == 0) {
+						t = (cursor.yvel > 0) ? 1 : 0;
+						b = (cursor.yvel < 0) ? 1 : 0;
+					}
+					if (l && r && cursor.yvel == 0) {
+						l = (cursor.xvel > 0) ? 1 : 0;
+						r = (cursor.xvel < 0) ? 1 : 0;
+					}
+
+					int x = (l) ? olxl-1 : (r ? olxr-1 : -1);
+					int y = (t) ? olyt-1 : (b ? olyb-1 : -1);
+					/* X coordinate of overlap between the Cursor, and Floor. */
+					/*if (cursor.a2 > floor.a1-(int)cursor.xvel-1)
+					else if (cursor.a1 < floor.a2-(int)cursor.xvel+1)
+						olx = cursor.a1-(floor.a2-(int)cursor.xvel+1);*/
+					/*int olw = (cursor.a1+rw1)-(floor.a1+rw2);*/
+
+					/* Y coordinate of overlap between the Cursor, and Floor. */
+					/*if (cursor.b2 > floor.b1-(int)cursor.yvel-1)
+						oly = cursor.b2-(floor.b1-(int)cursor.yvel-1);
+					else if (cursor.b1 < floor.b2-(int)cursor.yvel+1)
+						oly = cursor.b1-(floor.b2-(int)cursor.yvel+1);*/
+					/*int olh = (cursor.b1+rh1)-(floor.b1+rh2);*/
+
+					printf(
+						"olxab: %i, olyab: %i\n"
+						"olxl: %i, olyt: %i\n"
+						"olxr: %i, olyb: %i\n"
+						"cursor.a2: %i, cursor.b2: %i\n"
+						"floor.a2: %i, floor.b2: %i\n"
+						"x: %i, y: %i\n"
+						"min(cursor.b2, floor.b2)-max(cursor.b1, floor.b1): %i\n"
+						"min(cursor.b2, floor.b2): %i\n"
+						"max(cursor.b1, floor.b1): %i\n"
+						"t: %u, b: %u, l: %u, r: %u\n"
+						, olxab, olyab
+						, olxl, olyt
+						, olxr, olyb
+						, cursor.a2, cursor.b2
+						, floor.a2, floor.b2
+						, x, y
+						, min(cursor.b2, floor.b2)-max(cursor.b1, floor.b1)
+						, min(cursor.b2, floor.b2)
+						, max(cursor.b1, floor.b1)
+						, t, b, l, r);
+					if((x >= 0 && x < floor.w) && (y >= 0 && y <= floor.h))
+						for (y; y<floor.h; y++) {
+							for (x; x < floor.w; x++) {
+								/*printf(
+									"cursor.pos.x+x1: %i, cursor.pos.y+y1: %i\n"
+									"floor.pos.x+x2:  %i, floor.pos.y+y2:  %i\n"
+									"\n"
+									, cursor.pos.x+x1, cursor.pos.y+y1
+									, floor.pos.x+x2, floor.pos.y+y2);*/
+								if (cursor.bitmask[y][x] && floor.bitmask[y][x])
+									printf(
+										"Collision at: cursor (%i, %i)\n"
+										"              floor  (%i, %i)\n"
+										, cursor.a2-x, cursor.b2-y
+										, floor.a2-x, floor.b2-y);
+							}
+						}
+				}
+				printf("%u, %u\n%u\n%i, %i\n%07.06f, %07.06f\n", cursor.clx, cursor.cly, cursor.gnded, cursor.pos.x, cursor.pos.y, cursor.xvel, cursor.yvel);
+
+			} else {
+				cursor.c1 = cursor.pos.fx;
+				cursor.c2 = cursor.pos.fx+cursor.w;
+				cursor.d1 = cursor.pos.fy;
+				cursor.d2 = cursor.pos.fy+cursor.h;
+				floor.c1 = floor.pos.fx;
+				floor.c2 = floor.pos.fx+floor.w;
+				floor.d1 = floor.pos.fy;
+				floor.d2 = floor.pos.fy+floor.h;
+			}
+		}
+
 		/* Tile Heightmap Collision. */
 		if (colltype == THM && coll) {
 			if (!flt) {
@@ -229,9 +371,9 @@ int main(int argc, char **argv) {
 				if (cursor.clx) {
 					if (cursor.a2-floor.a1 < 0 || cursor.a2-floor.a1 > floor.w) {
 						/* Is the Cursor coming from the left? */
-						if (cursor.a2 > floor.a1-(int)cursor.xvel-1 && floor.b2-cursor.b2 < (int)floor.heightmap[0] && !floor.flp && cursor.xvel > 0)
+						if (cursor.a2 > floor.a1-(int)cursor.xvel-1 && floor.b2-cursor.b2 < (int)floor.bitmask[0] && !floor.flp && cursor.xvel > 0)
 							cursor.pos.x = (floor.pos.x-(int)cursor.xvel)-cursor.w-1;
-						else if (cursor.a1 < (floor.a2-cursor.w)-(int)cursor.xvel+1 && floor.b2-cursor.b2 < (int)floor.heightmap[floor.w-1] && !floor.flp && cursor.xvel < 0)
+						else if (cursor.a1 < (floor.a2-cursor.w)-(int)cursor.xvel+1 && floor.b2-cursor.b2 < (int)floor.bitmask[floor.w-1] && !floor.flp && cursor.xvel < 0)
 							cursor.pos.x = (floor.a2-cursor.w)-(int)cursor.xvel+1;
 						/* Is the Cursor coming from the right? */
 						if (cursor.a1 < (floor.a2-cursor.w)-(int)cursor.xvel+1 && cursor.b1-floor.b1 < 0 && floor.flp && cursor.xvel < 0)
@@ -244,7 +386,7 @@ int main(int argc, char **argv) {
 				if (cursor.cly) {
 					if (cursor.a2-floor.a1 < floor.w) {
 						cursor.yvel = 0;
-						newy = (int)floor.heightmap[cursor.a2-floor.a1];
+						newy = (int)floor.bitmask[cursor.a2-floor.a1];
 						/* Is the Floor, really a floor? */
 						if (cursor.b2 > (floor.b2-hmpeak)-(int)cursor.yvel && floor.b2-cursor.b2 >= 0 && !floor.flp)
 							cursor.pos.y = ((floor.b2-cursor.h)-newy)-(int)cursor.yvel;
@@ -288,9 +430,9 @@ int main(int argc, char **argv) {
 				if (cursor.clx) {
 					if (cursor.c2-floor.c1 < -1 || cursor.c2-floor.c1 > floor.w) {
 						/* Is the Cursor coming from the left? */
-						if (cursor.c2 > floor.c1-cursor.xvel-1 && floor.d2-cursor.d2 < (int)floor.heightmap[0] && !floor.flp && cursor.xvel > 0)
+						if (cursor.c2 > floor.c1-cursor.xvel-1 && floor.d2-cursor.d2 < (int)floor.bitmask[0] && !floor.flp && cursor.xvel > 0)
 							cursor.pos.fx = (floor.pos.x-cursor.xvel)-cursor.w-1;
-						else if (cursor.c1 < (floor.c2-cursor.w)-cursor.xvel+1 && floor.d2-cursor.d2 < (int)floor.heightmap[floor.w-1] && !floor.flp && cursor.xvel < 0)
+						else if (cursor.c1 < (floor.c2-cursor.w)-cursor.xvel+1 && floor.d2-cursor.d2 < (int)floor.bitmask[floor.w-1] && !floor.flp && cursor.xvel < 0)
 							cursor.pos.fx = (floor.c2-cursor.w)-cursor.xvel+1;
 						/* Is the Cursor coming from the right? */
 						if (cursor.c1 < (floor.c2-cursor.w)-cursor.xvel+1 && cursor.d1-floor.d1 < 0 && floor.flp && cursor.xvel < 0)
@@ -303,7 +445,7 @@ int main(int argc, char **argv) {
 				if (cursor.cly) {
 					if (cursor.c2-floor.c1 < floor.w) {
 						cursor.yvel = 0;
-						newy = (int)floor.heightmap[(int)cursor.c2-(int)floor.c1];
+						newy = (int)floor.bitmask[(int)cursor.c2-(int)floor.c1];
 						/* Is the Floor, really a floor? */
 						if (cursor.d2 > (floor.d2-hmpeak)-cursor.yvel && floor.d2-cursor.d2 >= 0 && !floor.flp)
 							cursor.pos.fy = ((floor.d2-cursor.h)-newy)-cursor.yvel;
@@ -406,8 +548,11 @@ int main(int argc, char **argv) {
 	uint8_t a = 0;
 	unsigned int i = 0;
 	free(buf);
-	if(colltype == THM) {
-		free(floor.heightmap);
+	if(colltype == THM || colltype == PPX) {
+		while (!a && colltype == PPX)
+			(i<tmp.h) ? (free(tmp.bitmask[i]), ++i) : (a=1);
+		free(cursor.bitmask);
+		free(floor.bitmask);
 	}
 	fflush(stdout);
 
diff --git a/test-ppx b/test-ppx
new file mode 100644
index 0000000..dca0772
--- /dev/null
+++ b/test-ppx
@@ -0,0 +1,56 @@
+2
+18, 34
+000000000000000000
+000000000000110000
+000000000001010000
+000000000010010000
+000000000010010000
+000000000010010000
+000000001111110000
+000000010000010000
+000000100000010000
+000001000000010000
+000001000000010000
+000010000000010000
+000010000000010000
+000001000000010000
+000001000000010000
+000000100000010000
+000000111111110000
+000000100000010000
+000001000111010000
+000001000101010000
+000001000101010000
+000001000111010000
+000001000101010000
+000001001001010000
+000001001101010000
+000000100111010000
+000000100000010000
+000000100000010000
+000000111111110000
+000000001001000000
+000000001111000000
+000000011001000000
+000000010001000000
+000000011111000000
+1, 2
+0, 0
+16, 16
+0000000000000001
+0000000000000011
+0000000000000101
+0000000000001001
+0000000000010001
+0000000000100001
+0000000001000001
+0000000010000001
+0000000100000001
+0000001000000001
+0000010000000001
+0000100000000001
+0001000000000001
+0010000000000001
+0100000000000001
+1111111111111111
+4, 5