From 7764a1bb5dcc8c91929c5c9a475e1f61633dce0c Mon Sep 17 00:00:00 2001
From: Sryder <sryder13@gmail.com>
Date: Fri, 16 Mar 2018 18:08:24 +0000
Subject: [PATCH] Match HWR_DrawFixedPatch to V_DrawFixedPatch

---
 src/hardware/hw_draw.c | 103 ++++++++++++++++++++++++++++++++---------
 1 file changed, 82 insertions(+), 21 deletions(-)

diff --git a/src/hardware/hw_draw.c b/src/hardware/hw_draw.c
index 867a86a15..30b0518cb 100644
--- a/src/hardware/hw_draw.c
+++ b/src/hardware/hw_draw.c
@@ -147,10 +147,7 @@ void HWR_DrawFixedPatch(GLPatch_t *gpatch, fixed_t x, fixed_t y, fixed_t pscale,
 //  | /|
 //  |/ |
 //  0--1
-	float sdupx = FIXED_TO_FLOAT(vid.fdupx)*2.0f;
-	float sdupy = FIXED_TO_FLOAT(vid.fdupy)*2.0f;
-	float pdupx = FIXED_TO_FLOAT(vid.fdupx)*2.0f*FIXED_TO_FLOAT(pscale);
-	float pdupy = FIXED_TO_FLOAT(vid.fdupy)*2.0f*FIXED_TO_FLOAT(pscale);
+	float dupx, dupy, fscale, fwidth, fheight;
 
 	if (alphalevel >= 10 && alphalevel < 13)
 		return;
@@ -161,40 +158,104 @@ void HWR_DrawFixedPatch(GLPatch_t *gpatch, fixed_t x, fixed_t y, fixed_t pscale,
 	else
 		HWR_GetMappedPatch(gpatch, colormap);
 
+	dupx = (float)vid.dupx;
+	dupy = (float)vid.dupy;
+
 	switch (option & V_SCALEPATCHMASK)
 	{
 	case V_NOSCALEPATCH:
-		pdupx = pdupy = 2.0f;
+		dupx = dupy = 1.0f;
 		break;
 	case V_SMALLSCALEPATCH:
-		pdupx = 2.0f * FIXED_TO_FLOAT(vid.fsmalldupx);
-		pdupy = 2.0f * FIXED_TO_FLOAT(vid.fsmalldupy);
+		dupx = (float)vid.smalldupx;
+		dupy = (float)vid.smalldupy;
 		break;
 	case V_MEDSCALEPATCH:
-		pdupx = 2.0f * FIXED_TO_FLOAT(vid.fmeddupx);
-		pdupy = 2.0f * FIXED_TO_FLOAT(vid.fmeddupy);
+		dupx = (float)vid.meddupx;
+		dupy = (float)vid.meddupy;
 		break;
 	}
 
-	if (option & V_NOSCALESTART)
-		sdupx = sdupy = 2.0f;
+	dupx = dupy = (dupx < dupy ? dupx : dupy);
+	fscale = FIXED_TO_FLOAT(pscale);
 
-	if (option & V_SPLITSCREEN)
-		sdupy /= 2.0f;
-
-	if (option & V_FLIP) // Need to flip both this and sow
+	if (option & V_OFFSET)
 	{
-		v[0].x = v[3].x = (cx*sdupx-(gpatch->width-gpatch->leftoffset)*pdupx)/vid.width - 1;
-		v[2].x = v[1].x = (cx*sdupx+gpatch->leftoffset*pdupx)/vid.width - 1;
+		cx -= (float)gpatch->leftoffset * dupx * fscale;
+		cy -= (float)gpatch->topoffset * dupy * fscale;
 	}
 	else
 	{
-		v[0].x = v[3].x = (cx*sdupx-gpatch->leftoffset*pdupx)/vid.width - 1;
-		v[2].x = v[1].x = (cx*sdupx+(gpatch->width-gpatch->leftoffset)*pdupx)/vid.width - 1;
+		cy -= (float)gpatch->topoffset * fscale;
+		if (option & V_FLIP)
+			cx -= ((float)gpatch->width - (float)gpatch->leftoffset) * fscale;
+		else
+			cx -= (float)gpatch->leftoffset * fscale;
 	}
 
-	v[0].y = v[1].y = 1-(cy*sdupy-gpatch->topoffset*pdupy)/vid.height;
-	v[2].y = v[3].y = 1-(cy*sdupy+(gpatch->height-gpatch->topoffset)*pdupy)/vid.height;
+	if (option & V_SPLITSCREEN)
+		cy /= 2;
+
+	if (!(option & V_NOSCALESTART))
+	{
+		cx = cx * dupx;
+		cy = cy * dupy;
+
+		if (!(option & V_SCALEPATCHMASK))
+		{
+			// centre screen
+			if (vid.width != BASEVIDWIDTH * vid.dupx)
+			{
+				if (option & V_SNAPTORIGHT)
+					cx += ((float)vid.width - ((float)BASEVIDWIDTH * dupx));
+				else if (!(option & V_SNAPTOLEFT))
+					cx += ((float)vid.width - ((float)BASEVIDWIDTH * dupx))/2;
+			}
+			if (vid.height != BASEVIDHEIGHT * vid.dupy)
+			{
+				if ((option & (V_SPLITSCREEN|V_SNAPTOBOTTOM)) == (V_SPLITSCREEN|V_SNAPTOBOTTOM))
+					cy += ((float)vid.height/2 - ((float)BASEVIDHEIGHT/2 * dupy));
+				else if (option & V_SNAPTOBOTTOM)
+					cy += ((float)vid.height - ((float)BASEVIDHEIGHT * dupy));
+				else if (!(option & V_SNAPTOTOP))
+					cy += ((float)vid.height - ((float)BASEVIDHEIGHT * dupy))/2;
+			}
+			// if it's meant to cover the whole screen, black out the rest
+			// TODO
+			/*if (x == 0 && SHORT(gpatch->width) == BASEVIDWIDTH && y == 0 && SHORT(gpatch->height) == BASEVIDHEIGHT)
+			{
+				const column_t *column = (const column_t *)((const UINT8 *)((patch_t *)gpatch) + LONG(((patch_t *)gpatch)->columnofs[0]));
+				const UINT8 *source = (const UINT8 *)(column) + 3;
+				HWR_DrawFill(0, 0, BASEVIDWIDTH, BASEVIDHEIGHT, (column->topdelta == 0xff ? 31 : source[0]));
+			}*/
+		}
+	}
+
+	if (pscale != FRACUNIT)
+	{
+		fwidth = (float)gpatch->width * fscale * dupx;
+		fheight = (float)gpatch->height * fscale * dupy;
+	}
+	else
+	{
+		fwidth = (float)gpatch->width * dupx;
+		fheight = (float)gpatch->height * dupy;
+	}
+
+	// positions of the cx, cy, are between 0 and vid.width/vid.height now, we need them to be between -1 and 1
+	cx = -1 + (cx / (vid.width/2));
+	cy = 1 - (cy / (vid.height/2));
+
+	// fwidth and fheight are similar
+	fwidth /= vid.width / 2;
+	fheight /= vid.height / 2;
+
+	// set the polygon vertices to the right positions
+	v[0].x = v[3].x = cx;
+	v[2].x = v[1].x = cx + fwidth;
+
+	v[0].y = v[1].y = cy;
+	v[2].y = v[3].y = cy - fheight;
 
 	v[0].z = v[1].z = v[2].z = v[3].z = 1.0f;