From 5f06a62aff1499ed0caf68ff7e551c5c02dded61 Mon Sep 17 00:00:00 2001
From: Kai Stevenson <kai@kaistevenson.com>
Date: Mon, 6 Feb 2023 13:29:55 -0800
Subject: dynamic tails

---
 snake.c | 46 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 38 insertions(+), 8 deletions(-)

diff --git a/snake.c b/snake.c
index 7b286ea..e87660e 100644
--- a/snake.c
+++ b/snake.c
@@ -41,7 +41,7 @@ int main(int argc, char **argv) {
 			printf("for more information, see the license file.\n");
 			return 0;
 		}
-		else if (strcmp("--help", argv[1]) == 0) {
+		else if(strcmp("--help", argv[1]) == 0) {
 			printf("usage: snake3 [--version] [--help]\n");
 			return 0;
 		}
@@ -113,8 +113,6 @@ int main(int argc, char **argv) {
 		if((dir.mx != 0 || dir.my != 0) && !(dir.mx == 1 && lastMoveDir.mx == -1) && !(dir.mx == -1 && lastMoveDir.mx == 1) && !(dir.my == 1 && lastMoveDir.my == -1) && !(dir.my == -1 && lastMoveDir.my == 1)) {
 			lastMoveDir = dir;
 		}
-		else {
-		}
 		/* check if snake landed on the food */
 		int ateFood = 0;
 		if((snakePositions.vectors[0].mx + lastMoveDir.mx == foodPos.mx) && (snakePositions.vectors[0].my + lastMoveDir.my == foodPos.my)) {
@@ -209,14 +207,41 @@ void draw_board() {
 		for(int c = 0; c < boardSize; c++) {
 			/* determine the contents of the board position */
 			int type = 0;
+			/* 0=horizontal, 1=vertical, 2=diagonal slant right, 3=diagonal slant left */
+			int tailOrientation = 0;
 			for(int i = 0; i < snakePositions.length; i++) {
 				if(snakePositions.vectors[i].mx == c && snakePositions.vectors[i].my == r) {
-					type = i ? 2 : 1;
+					if(i > 0) {
+						type = 2;
+						/* get the delta to the connecting tail */
+						int dx;
+						int dy;
+						if(i < snakePositions.length - 1) {
+							dx = snakePositions.vectors[i - 1].mx - snakePositions.vectors[i + 1].mx;
+							dy = snakePositions.vectors[i - 1].my - snakePositions.vectors[i + 1].my;
+						}
+						else {
+							dx = snakePositions.vectors[i - 1].mx - c;
+							dy = snakePositions.vectors[i - 1].my - r;
+						}
+						if(dy == 0) {
+							tailOrientation = 0;
+						}
+						else if(dx == 0) {
+							tailOrientation = 1;
+						}
+						else if((dx == 1 && dy == 1) || (dx == -1 && dy == -1)) {
+							tailOrientation = 3;
+						}
+						else if((dx == -1 && dy == 1) || (dx == 1 && dy == -1)) {
+							tailOrientation = 2;
+						}
+					}
+					else {
+						type = 1;
+					}
 					break;
 				}
-				else {
-					type = 0;
-				}
 			}
 			if(foodPos.mx == c && foodPos.my == r) {
 				type = 3;
@@ -232,7 +257,12 @@ void draw_board() {
 			}
 			else if(type == 2) {
 				/* snake body */
-				printf("%s* %s", GRN, COLOR_RESET);
+				char bodyChar = tailOrientation == 0 ? '-'
+					: tailOrientation == 1 ? '|'
+					: tailOrientation == 2 ? '/'
+					: tailOrientation == 3 ? '\\'
+					: '*';
+				printf("%s%c %s", GRN, bodyChar, COLOR_RESET);
 			}
 			else if(type == 3) {
 				/* food */
-- 
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