From 691942dfbe845bc40524e22bcb6696dbc945a5ea Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miloslav=20=C4=8C=C3=AD=C5=BE?= <tastyfish@seznam.cz>
Date: Sat, 15 Sep 2018 11:56:20 +0200
Subject: [PATCH] Roll texture coords

---
 raycastlib.h | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/raycastlib.h b/raycastlib.h
index 46489d2..9794424 100644
--- a/raycastlib.h
+++ b/raycastlib.h
@@ -46,12 +46,18 @@
 #endif
 
 #ifndef USE_DIST_APPROX
-#define USE_DIST_APPROX 0 /** What distance approximation to use:
+#define USE_DIST_APPROX 0 /**< What distance approximation to use:
                             0: none (compute full Euclidean distance)
                             1: accurate approximation
                             2: octagonal approximation (LQ) */
 #endif
 
+#ifndef ROLL_TEXTURE_COORDS
+#define ROLL_TEXTURE_COORDS 1 /**< Says whether rolling doors should also roll
+                                   the texture coordinates along (mostly
+                                   desired for doors). */
+#endif
+
 #ifndef VERTICAL_FOV
 #define VERTICAL_FOV (UNITS_PER_SQUARE / 2)
 #endif
@@ -1027,11 +1033,9 @@ void _columnFunctionSimple(HitResult *hits, uint16_t hitCount, uint16_t x,
       {
         // normal hit, check the door roll
 
-        Unit doorRoll = hit.doorRoll;
-
-        int8_t unrolled = doorRoll >= 0 ?
-          doorRoll > hit.textureCoord :
-          hit.textureCoord > UNITS_PER_SQUARE + doorRoll;
+        int8_t unrolled = hit.doorRoll >= 0 ?
+          hit.doorRoll > hit.textureCoord :
+          hit.textureCoord > UNITS_PER_SQUARE + hit.doorRoll;
 
         if (unrolled)
         {
@@ -1105,6 +1109,10 @@ void _columnFunctionSimple(HitResult *hits, uint16_t hitCount, uint16_t x,
   p.isFloor = 1;
   p.depth = dist;
 
+#if ROLL_TEXTURE_COORDS == 1 
+  p.hit.textureCoord -= p.hit.doorRoll;
+#endif
+
   while (y < wallEnd)
   {
     p.position.y = y;