Merge remote-tracking branch 'zdoom/master' into qzdoom

src/asm_ia32/tmap2.asm

@@ -198,7 +198,10 @@ SetTiltedSpanSize:
 	mov	[y8+2],cl
 	mov	[y9+2],cl
 	mov	[y10+2],cl
+	cmp	eax,0		; if x bits is 0, mask must be 0 too.
+	jz	.notted
 	not	eax
+.notted:
 	pop	ecx
 	
 	mov	[m1+2],eax

src/r_plane.cpp

@@ -224,10 +224,26 @@ void R_MapPlane (int y, int x1)
 
 	distance = planeheight * yslope[y];
 
+	if (ds_xbits != 0)
+	{
 		ds_xstep = xs_ToFixed(32 - ds_xbits, distance * xstepscale);
-	ds_ystep = xs_ToFixed(32-ds_ybits, distance * ystepscale);
 		ds_xfrac = xs_ToFixed(32 - ds_xbits, distance * basexfrac) + pviewx;
+	}
+	else
+	{
+		ds_xstep = 0;
+		ds_xfrac = 0;
+	}
+	if (ds_ybits != 0)
+	{
+		ds_ystep = xs_ToFixed(32 - ds_ybits, distance * ystepscale);
 		ds_yfrac = xs_ToFixed(32 - ds_ybits, distance * baseyfrac) + pviewy;
+	}
+	else
+	{
+		ds_ystep = 0;
+		ds_yfrac = 0;
+	}
 
 	if (plane_shade)
 	{
@@ -2116,6 +2132,15 @@ void R_DrawTiltedPlane (visplane_t *pl, double _xscale, double _yscale, fixed_t
 		}
 	}
 
+	// Hack in support for 1 x Z and Z x 1 texture sizes
+	if (ds_ybits == 0)
+	{
+		plane_sv[2] = plane_sv[1] = plane_sv[0] = 0;
+	}
+	if (ds_xbits == 0)
+	{
+		plane_su[2] = plane_su[1] = plane_su[0] = 0;
+	}
 #if defined(X86_ASM)
 	if (!r_swtruecolor)
 	{

src/r_segs.cpp

@@ -1093,7 +1093,10 @@ WallscanSampler::WallscanSampler(int y1, float swal, double yrepeat, fixed_t xof
 	if (!r_swtruecolor)
 	{
 		height = texture->GetHeight();
+
 		int uv_fracbits = 32 - texture->HeightBits;
+		if (uv_fracbits != 32)
+		{
 			uv_max = height << uv_fracbits;
 
 			// Find start uv in [0-base_height[ range.
@@ -1108,6 +1111,13 @@ WallscanSampler::WallscanSampler(int y1, float swal, double yrepeat, fixed_t xof
 			uv_step = xs_ToFixed(uv_fracbits, uv_stepd);
 			if (uv_step == 0) // To prevent divide by zero elsewhere
 				uv_step = 1;
+		}
+		else
+		{ // Hack for one pixel tall textures
+			uv_pos = 0;
+			uv_step = 0;
+			uv_max = 1;
+		}
 
 		source = getcol(texture, xoffset >> FRACBITS);
 		source2 = nullptr;
@@ -1368,11 +1378,19 @@ void wallscan_any(
 		return;
 
 	fixed_t xoffset = rw_offset;
+
 	rw_pic->GetHeight(); // To ensure that rw_pic->HeightBits has been set
+	int fracbits = 32 - rw_pic->HeightBits;
+	if (fracbits == 32)
+	{ // Hack for one pixel tall textures
+		fracbits = 0;
+		yrepeat = 0;
+		dc_texturemid = 0;
+	}
 
 	DWORD(*draw1column)();
 	void(*draw4columns)();
-	setupwallscan(r_swtruecolor ? FRACBITS : 32 - rw_pic->HeightBits, draw1column, draw4columns);
+	setupwallscan(r_swtruecolor ? FRACBITS : fracbits, draw1column, draw4columns);
 
 	bool fixed = (fixedcolormap != NULL || fixedlightlev >= 0);
 	if (fixed)

src/textures/texture.cpp

@@ -241,8 +241,9 @@ void FTexture::CalcBitSize ()
 	}
 	WidthMask = (1 << WidthBits) - 1;
 
-	// The minimum height is 2, because we cannot shift right 32 bits.
-	for (i = 1; (1 << i) < Height; ++i)
+	// <hr>The minimum height is 2, because we cannot shift right 32 bits.</hr>
+	// Scratch that. Somebody actually made a 1x1 texture, so now we have to handle it.
+	for (i = 0; (1 << i) < Height; ++i)
 	{ }
 
 	HeightBits = i;