From 4627d6c939b3b2d8153aca18f633a2580ecab028 Mon Sep 17 00:00:00 2001
From: pelya <x.pelya.x@gmail.com>
Date: Sun, 15 Jun 2014 23:18:37 +0300
Subject: [PATCH] Fixed game crash when two vehicles crash

---
 src/blitter/16bpp_base.hpp   | 23 ++++++++++++++++++++---
 src/blitter/16bpp_simple.cpp | 12 ++++++++++++
 2 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/src/blitter/16bpp_base.hpp b/src/blitter/16bpp_base.hpp
index e7a5b5e7a9..c4d63b0bd4 100644
--- a/src/blitter/16bpp_base.hpp
+++ b/src/blitter/16bpp_base.hpp
@@ -163,9 +163,9 @@ public:
 	 */
 	static inline Colour16 MakeGrey(Colour16 colour)
 	{
-		uint r = colour.r;
-		uint g = colour.g;
-		uint b = colour.b;
+		uint8 r = colour.r;
+		uint8 g = colour.g;
+		uint8 b = colour.b;
 
 		/* To avoid doubles and stuff, multiple it with a total of 65536 (16bits), then
 		 *  divide by it to normalize the value to a byte again. See heightmap.cpp for
@@ -175,6 +175,23 @@ public:
 		return To16(grey, grey, grey);
 	}
 
+	/**
+	 * Make a colour dark grey, for specialized 32bpp remapping.
+	 * @param r red component
+	 * @param g green component
+	 * @param b blue component
+	 * @return the brightness value of the new colour, now dark grey.
+	 */
+	static inline uint8 MakeDark(Colour16 colour)
+	{
+		uint8 r = colour.r;
+		uint8 g = colour.g;
+		uint8 b = colour.b;
+
+		/* Magic-numbers are ~66% of those used in MakeGrey() */
+		return (((r << 3) * 13063) + ((g << 2) * 25647) + ((b << 3) * 4981)) / 65536;
+	}
+
 	enum { DEFAULT_BRIGHTNESS = 8 };
 
 	/**
diff --git a/src/blitter/16bpp_simple.cpp b/src/blitter/16bpp_simple.cpp
index 36f90f17b6..675b58b87d 100644
--- a/src/blitter/16bpp_simple.cpp
+++ b/src/blitter/16bpp_simple.cpp
@@ -46,6 +46,17 @@ void Blitter_16bppSimple::Draw(const Blitter::BlitterParams *bp, ZoomLevel zoom)
 					}
 					break;
 
+				case BM_CRASH_REMAP:
+					if (src->m == 0) {
+						if (src->a != 0) {
+							uint8 g = MakeDark(src->c);
+							*dst = ComposeColourRGBA(g, g, g, src->a, *dst);
+						}
+					} else {
+						if (bp->remap[src->m] != 0) *dst = ComposeColourPA(AdjustBrightness(LookupColourInPalette(bp->remap[src->m]), src->v), src->a, *dst);
+					}
+					break;
+
 				case BM_TRANSPARENT:
 					/* TODO -- We make an assumption here that the remap in fact is transparency, not some colour.
 					 *  This is never a problem with the code we produce, but newgrfs can make it fail... or at least:
@@ -72,6 +83,7 @@ void Blitter_16bppSimple::Draw(Blitter::BlitterParams *bp, BlitterMode mode, Zoo
 		case BM_NORMAL:       Draw<BM_NORMAL>      (bp, zoom); return;
 		case BM_COLOUR_REMAP: Draw<BM_COLOUR_REMAP>(bp, zoom); return;
 		case BM_TRANSPARENT:  Draw<BM_TRANSPARENT> (bp, zoom); return;
+		case BM_CRASH_REMAP:  Draw<BM_CRASH_REMAP> (bp, zoom); return;
 	}
 }