From b4f1cf63531ba7553f2effcf8cebae0ed731f1cf Mon Sep 17 00:00:00 2001
From: Daniele Verducci <daniele.verducci@ichibi.eu>
Date: Tue, 10 Jan 2023 19:01:57 +0100
Subject: [PATCH] Better clipping

---
 v2/raycaster.py | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/v2/raycaster.py b/v2/raycaster.py
index 7946ab2..ac216d7 100755
--- a/v2/raycaster.py
+++ b/v2/raycaster.py
@@ -366,20 +366,28 @@ class Main:
 
 				# Clipping
 				lineEnd = textureSegmentEnd
-				if lineEnd > lineOffset + lineHeight:
-					lineEnd = lineOffset + lineHeight
+				if lineEnd > RAYCAST_RENDER_HEIGHT:
+					lineEnd = RAYCAST_RENDER_HEIGHT
 				lineStart = textureSegmentStart
 				if lineStart < 0:
 					lineStart = 0
+				if lineEnd < lineStart:
+					continue
+
 				# Upscaling
 				lineStart = lineStart * RAYCAST_RESOLUTION_SCALING
 				lineEnd = lineEnd * RAYCAST_RESOLUTION_SCALING
+
 				# Draw segment
 				for repeat in range(1, RAYCAST_RESOLUTION_SCALING + 1):
 					x = i * RAYCAST_RESOLUTION_SCALING + repeat
 					self.drawVline(self.raycastSurface, color, x, int(lineStart), int(lineEnd))
 
 	def drawVline(self, surface, color, x, startY, endY):
+		if x < 0 or x > RAYCAST_WIN_WIDTH or startY < 0 or endY > RAYCAST_WIN_HEIGHT or endY < startY:
+			print("Trying to write outside bounds: vertical line with x {} from y {} to y {}".format(x, startY, endY))
+			return
+
 		startIdx = startY * RAYCAST_WIN_WIDTH + x
 		for idx in range(startIdx, endY * RAYCAST_WIN_WIDTH + x, RAYCAST_WIN_WIDTH):
 			self.raycast_u32_pixels[idx] = color