From 1c9b6930874a4e14ab4314bf4787120a57e86d01 Mon Sep 17 00:00:00 2001
From: Randy Heit <rheit@zdoom.fake>
Date: Sat, 24 Oct 2009 04:39:36 +0000
Subject: [PATCH] - Fixed drawing of wide high resolution skies. (At least for
 the samples I   received. I'm not convinced that it's yet fixed for the
 general case.)

SVN r1930 (trunk)
---
 docs/rh-log.txt |  4 ++++
 src/r_anim.cpp  |  4 ++--
 src/r_plane.cpp | 17 ++++++++++-------
 src/r_sky.cpp   | 10 ++++------
 4 files changed, 20 insertions(+), 15 deletions(-)

diff --git a/docs/rh-log.txt b/docs/rh-log.txt
index 39c76062e..ed25d858d 100644
--- a/docs/rh-log.txt
+++ b/docs/rh-log.txt
@@ -1,3 +1,7 @@
+October 23, 2009
+- Fixed drawing of wide high resolution skies. (At least for the samples I
+  received. I'm not convinced that it's yet fixed for the general case.)
+
 October 19, 2009  (Changes by Graf Zahl)
 - fixed: Setting the first state's duration of a fast projectile to 0 caused
   an underflow and blocked all further state changes.
diff --git a/src/r_anim.cpp b/src/r_anim.cpp
index 22c85c50d..43e3b50a3 100644
--- a/src/r_anim.cpp
+++ b/src/r_anim.cpp
@@ -834,6 +834,6 @@ void R_UpdateAnimations (DWORD mstime)
 
 	// Scroll the sky
 	double ms = (double)mstime * FRACUNIT;
-	sky1pos = fixed_t(fmod (ms * level.skyspeed1, double(TexMan[sky1texture]->GetWidth() << FRACBITS)));
-	sky2pos = fixed_t(fmod (ms * level.skyspeed2, double(TexMan[sky2texture]->GetWidth() << FRACBITS)));
+	sky1pos = fixed_t(fmod (ms * level.skyspeed1, double(TexMan[sky1texture]->GetScaledWidth() << FRACBITS)));
+	sky2pos = fixed_t(fmod (ms * level.skyspeed2, double(TexMan[sky2texture]->GetScaledWidth() << FRACBITS)));
 }
diff --git a/src/r_plane.cpp b/src/r_plane.cpp
index 69af40223..d177241c6 100644
--- a/src/r_plane.cpp
+++ b/src/r_plane.cpp
@@ -764,17 +764,16 @@ static int skycolplace;
 // Get a column of sky when there is only one sky texture.
 static const BYTE *R_GetOneSkyColumn (FTexture *fronttex, int x)
 {
-	angle_t column = MulScale16 (frontxScale, viewangle + xtoviewangle[x]);
-
-	return fronttex->GetColumn ((((column^skyflip) >> sky1shift) + frontpos) >> FRACBITS, NULL);
+	angle_t column = (viewangle + xtoviewangle[x]) ^ skyflip;
+	return fronttex->GetColumn (MulScale32((column >> sky1shift) + frontpos, frontxScale), NULL);
 }
 
 // Get a column of sky when there are two overlapping sky textures
 static const BYTE *R_GetTwoSkyColumns (FTexture *fronttex, int x)
 {
-	DWORD ang = (viewangle + xtoviewangle[x])^skyflip;
-	DWORD angle1 = (((DWORD)MulScale16 (frontxScale, ang) >> sky1shift) + frontpos) >> FRACBITS;
-	DWORD angle2 = (((DWORD)MulScale16 (backxScale, ang) >> sky2shift) + backpos) >> FRACBITS;
+	DWORD ang = (viewangle + xtoviewangle[x]) ^ skyflip;
+	DWORD angle1 = (DWORD)MulScale32((ang >> sky1shift) + frontpos, frontxScale);
+	DWORD angle2 = (DWORD)MulScale32((ang >> sky2shift) + backpos, backxScale);
 
 	// Check if this column has already been built. If so, there's
 	// no reason to waste time building it again.
@@ -825,7 +824,6 @@ static void R_DrawSky (visplane_t *pl)
 	dc_iscale = skyiscale >> skystretch;
 
 	clearbuf (swall+pl->minx, pl->maxx-pl->minx+1, dc_iscale<<2);
-	rw_offset = frontpos;
 
 	if (MirrorFlags & RF_XFLIP)
 	{
@@ -1328,6 +1326,11 @@ void R_DrawSkyPlane (visplane_t *pl)
 			skyflip = l->args[2] ? 0u : ~0u;
 		}
 	}
+//	frontpos = FixedMul(frontpos, frontskytex->xScale/2);
+	if (backskytex != NULL)
+	{
+		backpos = FixedMul(backpos, backskytex->xScale);
+	}
 
 	bool fakefixed = false;
 	if (fixedcolormap)
diff --git a/src/r_sky.cpp b/src/r_sky.cpp
index 76e4d9d62..0ef9b259f 100644
--- a/src/r_sky.cpp
+++ b/src/r_sky.cpp
@@ -115,11 +115,9 @@ void R_InitSkyMap ()
 	}
 
 	// The (standard Doom) sky map is 256*128*4 maps.
-	sky1shift = 22+skystretch-16;
-	sky2shift = 22+skystretch-16;
-	if (skytex1->WidthBits >= 9)
-		sky1shift -= skystretch;
-	if (skytex2->WidthBits >= 9)
-		sky2shift -= skystretch;
+	int swidth = skytex1->GetScaledWidth();
+	sky1shift = 22 - 16 + (skystretch && swidth < 512) - (swidth >= 1024 && skytex1->xScale >= 4*FRACUNIT);
+	swidth = skytex2->GetScaledWidth();
+	sky2shift = 22 - 16 + (skystretch && swidth < 512) - (swidth >= 1024 && skytex2->xScale >= 4*FRACUNIT);
 }