From 51b0126d6d7f8ab48a7f495e5678ea4cd24bc381 Mon Sep 17 00:00:00 2001
From: Lactozilla <jp6781615@gmail.com>
Date: Tue, 28 Nov 2023 13:46:03 -0300
Subject: [PATCH] Fix V_DrawStretchyFixedPatch and V_DrawCroppedPatch

---
 src/v_video.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/src/v_video.c b/src/v_video.c
index 3226fc1d5..17e19f6a5 100644
--- a/src/v_video.c
+++ b/src/v_video.c
@@ -676,8 +676,6 @@ void V_DrawStretchyFixedPatch(fixed_t x, fixed_t y, fixed_t pscale, fixed_t vsca
 	if (!desttop)
 		return;
 
-	deststop = desttop + vid.rowbytes * vid.width;
-
 	if (scrn & V_NOSCALESTART)
 	{
 		x >>= FRACBITS;
@@ -778,9 +776,12 @@ void V_DrawStretchyFixedPatch(fixed_t x, fixed_t y, fixed_t pscale, fixed_t vsca
 				dest = deststart + (destend - desttop);
 			dest += FixedInt(FixedMul(topdelta<<FRACBITS,vdup));
 
+			UINT8 *col_start = screens[0] + ((x + offx)*vid.height);
+			deststop = col_start + vid.height;
+
 			for (ofs = 0; dest < deststop && (ofs>>FRACBITS) < column->length; ofs += rowfrac)
 			{
-				if (dest >= screens[scrn&V_PARAMMASK]) // don't draw off the top of the screen (CRASH PREVENTION)
+				if (dest >= col_start) // don't draw off the top of the screen (CRASH PREVENTION)
 					*dest = patchdrawfunc(dest, source, ofs);
 				dest++;
 			}
@@ -795,7 +796,6 @@ void V_DrawCroppedPatch(fixed_t x, fixed_t y, fixed_t pscale, fixed_t vscale, IN
 	UINT8 (*patchdrawfunc)(const UINT8*, const UINT8*, fixed_t);
 	UINT32 alphalevel = ((scrn & V_ALPHAMASK) >> V_ALPHASHIFT);
 	UINT32 blendmode = ((scrn & V_BLENDMASK) >> V_BLENDSHIFT);
-	// boolean flip = false;
 
 	fixed_t col, ofs, colfrac, rowfrac, fdup, vdup;
 	INT32 dup;
@@ -944,7 +944,7 @@ void V_DrawCroppedPatch(fixed_t x, fixed_t y, fixed_t pscale, fixed_t vscale, IN
 	if (!desttop)
 		return;
 
-	deststop = desttop + vid.rowbytes * vid.width;
+	int stop_pos = vid.height;
 
 	if (scrn & V_NOSCALESTART)
 	{
@@ -1011,7 +1011,7 @@ void V_DrawCroppedPatch(fixed_t x, fixed_t y, fixed_t pscale, fixed_t vscale, IN
 			if (stplyr == &players[displayplayer]) // Player 1's screen, crop at the bottom
 			{
 				// Just put a big old stop sign halfway through the screen
-				deststop -= vid.height>>1;
+				stop_pos -= vid.height>>1;
 			}
 			else //if (stplyr == &players[secondarydisplayplayer]) // Player 2's screen, crop at the top
 			{
@@ -1050,9 +1050,12 @@ void V_DrawCroppedPatch(fixed_t x, fixed_t y, fixed_t pscale, fixed_t vscale, IN
 			else
 				ofs = sy-(topdelta<<FRACBITS);
 
+			UINT8 *col_start = screens[0] + (x*vid.height);
+			deststop = col_start + stop_pos;
+
 			for (; dest < deststop && (ofs>>FRACBITS) < column->length && ((ofs - sy) + (topdelta<<FRACBITS)) < h; ofs += rowfrac)
 			{
-				if (dest >= screens[scrn&V_PARAMMASK]) // don't draw off the top of the screen (CRASH PREVENTION)
+				if (dest >= col_start) // don't draw off the top of the screen (CRASH PREVENTION)
 					*dest = patchdrawfunc(dest, source, ofs);
 				dest++;
 			}