diff --git a/Source/control.cpp b/Source/control.cpp
index 5e267dc64..63841b89b 100644
--- a/Source/control.cpp
+++ b/Source/control.cpp
@@ -145,14 +145,14 @@ char SpellITbl[MAX_SPELLS] = {
 	39, 42, 41, 40, 10, 36, 30
 };
 int PanBtnPos[8][5] = {
-	{ 9, 361, 71, 19, 1 },
-	{ 9, 387, 71, 19, 0 },
-	{ 9, 427, 71, 19, 1 },
-	{ 9, 453, 71, 19, 0 },
-	{ 560, 361, 71, 19, 1 },
-	{ 560, 387, 71, 19, 0 },
-	{ 87, 443, 33, 32, 1 },
-	{ 527, 443, 33, 32, 1 }
+	{ PANEL_LEFT +   9, PANEL_TOP +   9, 71, 19, 1 }, // char button
+	{ PANEL_LEFT +   9, PANEL_TOP +  35, 71, 19, 0 }, // quests button
+	{ PANEL_LEFT +   9, PANEL_TOP +  75, 71, 19, 1 }, // map button
+	{ PANEL_LEFT +   9, PANEL_TOP + 101, 71, 19, 0 }, // menu button
+	{ PANEL_LEFT + 560, PANEL_TOP +   9, 71, 19, 1 }, // inv button
+	{ PANEL_LEFT + 560, PANEL_TOP +  35, 71, 19, 0 }, // spells button
+	{ PANEL_LEFT +  87, PANEL_TOP +  91, 33, 32, 1 }, // chat button
+	{ PANEL_LEFT + 527, PANEL_TOP +  91, 33, 32, 1 }, // friendly fire button
 };
 char *PanBtnHotKey[8] = { "'c'", "'q'", "Tab", "Esc", "'i'", "'b'", "Enter", NULL };
 char *PanBtnStr[8] = {
@@ -382,9 +382,9 @@ void DrawSpell()
 		st = RSPLTYPE_INVALID;
 	SetSpellTrans(st);
 	if (spl != SPL_INVALID)
-		DrawSpellCel(629, 631, pSpellCels, SpellITbl[spl], 56);
+		DrawSpellCel(PANEL_X + 565, PANEL_Y + 119, pSpellCels, SpellITbl[spl], 56);
 	else
-		DrawSpellCel(629, 631, pSpellCels, 27, 56);
+		DrawSpellCel(PANEL_X + 565, PANEL_Y + 119, pSpellCels, 27, 56);
 }
 
 void DrawSpellList()
@@ -879,7 +879,7 @@ void DrawPanelBox(int x, int y, int w, int h, int sx, int sy)
 	/// ASSERT: assert(gpBuffer);
 
 	nSrcOff = x + PANEL_WIDTH * y;
-	nDstOff = sx + BUFFER_WIDTH * sy + (SCREEN_WIDTH - PANEL_WIDTH) / 2;
+	nDstOff = sx + BUFFER_WIDTH * sy + PANEL_LEFT;
 
 #ifdef USE_ASM
 	__asm {
@@ -950,14 +950,14 @@ void DrawPanelBox(int x, int y, int w, int h, int sx, int sy)
 /**
  * Draws parts of the flasks that are on the panel
  */
-void SetFlaskHeight(BYTE *pCelBuff, int min, int max, int c, int r)
+void SetFlaskHeight(BYTE *pCelBuff, int min, int max, int sx, int sy)
 {
 	int nSrcOff, nDstOff, w;
 
 	/// ASSERT: assert(gpBuffer);
 
 	nSrcOff = 88 * min;
-	nDstOff = c + BUFFER_WIDTH * r;
+	nDstOff = sx + BUFFER_WIDTH * sy;
 	w = max - min;
 
 #ifdef USE_ASM
@@ -1058,9 +1058,9 @@ void UpdateLifeFlask()
 	else if (filled < 0)
 		filled = 0;
 	if (filled != 69)
-		SetFlaskHeight(pLifeBuff, 16, 85 - filled, 96 + SCREEN_X, 352 + SCREEN_Y);
+		SetFlaskHeight(pLifeBuff, 16, 85 - filled, 96 + PANEL_X, PANEL_Y);
 	if (filled)
-		DrawPanelBox(96, 85 - filled, 88, filled, 96 + SCREEN_X, 421 + SCREEN_Y - filled);
+		DrawPanelBox(96, 85 - filled, 88, filled, 96 + PANEL_X, PANEL_Y + 69 - filled);
 }
 
 void DrawManaFlask()
@@ -1115,9 +1115,9 @@ void UpdateManaFlask()
 	if (filled > 69)
 		filled = 69;
 	if (filled != 69)
-		SetFlaskHeight(pManaBuff, 16, 85 - filled, 96 + SCREEN_X + 368, 352 + SCREEN_Y);
+		SetFlaskHeight(pManaBuff, 16, 85 - filled, 96 + PANEL_X + 368, PANEL_Y);
 	if (filled)
-		DrawPanelBox(96 + 368, 85 - filled, 88, filled, 96 + SCREEN_X + 368, 421 + SCREEN_Y - filled);
+		DrawPanelBox(96 + 368, 85 - filled, 88, filled, 96 + PANEL_X + 368, PANEL_Y + 69 - filled);
 
 	DrawSpell();
 }
@@ -1208,7 +1208,7 @@ void InitControlPan()
 
 void ClearCtrlPan()
 {
-	DrawPanelBox(0, sgbPlrTalkTbl + 16, PANEL_WIDTH, PANEL_HEIGHT, 64, 512);
+	DrawPanelBox(0, sgbPlrTalkTbl + 16, PANEL_WIDTH, PANEL_HEIGHT, PANEL_X, PANEL_Y);
 	DrawInfoBox();
 }
 
@@ -1218,16 +1218,16 @@ void DrawCtrlPan()
 
 	for (i = 0; i < 6; i++) {
 		if (!panbtn[i])
-			DrawPanelBox(PanBtnPos[i][0], PanBtnPos[i][1] - 336, 71, 20, PanBtnPos[i][0] + SCREEN_X, PanBtnPos[i][1] + SCREEN_Y);
+			DrawPanelBox(PanBtnPos[i][0] - PANEL_LEFT, PanBtnPos[i][1] - (PANEL_TOP - 16), 71, 20, PanBtnPos[i][0] + PANEL_X, PanBtnPos[i][1] + SCREEN_Y);
 		else
-			CelDraw(PanBtnPos[i][0] + SCREEN_X, PanBtnPos[i][1] + SCREEN_Y + 18, pPanelButtons, i + 1, 71);
+			CelDraw(PanBtnPos[i][0] + PANEL_X, PanBtnPos[i][1] + (PANEL_Y - 334), pPanelButtons, i + 1, 71);
 	}
 	if (numpanbtns == 8) {
-		CelDraw(87 + SCREEN_X, 474 + SCREEN_Y, pMultiBtns, panbtn[6] + 1, 33);
+		CelDraw(87 + PANEL_X, 122 + PANEL_Y, pMultiBtns, panbtn[6] + 1, 33);
 		if (FriendlyMode)
-			CelDraw(527 + SCREEN_X, 474 + SCREEN_Y, pMultiBtns, panbtn[7] + 3, 33);
+			CelDraw(527 + PANEL_X, 122 + PANEL_Y, pMultiBtns, panbtn[7] + 3, 33);
 		else
-			CelDraw(527 + SCREEN_X, 474 + SCREEN_Y, pMultiBtns, panbtn[7] + 5, 33);
+			CelDraw(527 + PANEL_X, 122 + PANEL_Y, pMultiBtns, panbtn[7] + 5, 33);
 	}
 }
 
@@ -1297,7 +1297,7 @@ void DoPanBtn()
 			}
 		}
 	}
-	if (!spselflag && MouseX >= 565 && MouseX < 621 && MouseY >= 416 && MouseY < 472) {
+	if (!spselflag && MouseX >= 565 + PANEL_LEFT && MouseX < 621 + PANEL_LEFT && MouseY >= 64 + PANEL_TOP && MouseY < 120 + PANEL_TOP) {
 		DoSpeedBook();
 		gamemenu_off();
 	}
@@ -1366,7 +1366,7 @@ void CheckPanelInfo()
 			pinfoflag = TRUE;
 		}
 	}
-	if (!spselflag && MouseX >= 565 && MouseX < 621 && MouseY >= 416 && MouseY < 472) {
+	if (!spselflag && MouseX >= 565 + PANEL_LEFT && MouseX < 621 + PANEL_LEFT && MouseY >= 64 + PANEL_TOP && MouseY < 120 + PANEL_TOP) {
 		strcpy(infostr, "Select current spell button");
 		infoclr = COL_WHITE;
 		panelflag = TRUE;
@@ -1428,7 +1428,7 @@ void CheckPanelInfo()
 			}
 		}
 	}
-	if (MouseX > 190 && MouseX < 437 && MouseY > 356 && MouseY < 385)
+	if (MouseX > 190 + PANEL_LEFT && MouseX < 437 + PANEL_LEFT && MouseY > 4 + PANEL_TOP && MouseY < 33 + PANEL_TOP)
 		pcursinvitem = CheckInvHLight();
 }
 
@@ -1548,7 +1548,7 @@ void DrawInfoBox()
 {
 	int nGold;
 
-	DrawPanelBox(177, 62, 288, 60, 241, 558);
+	DrawPanelBox(177, 62, 288, 60, PANEL_X + 177, PANEL_Y + 46);
 	if (!panelflag && !trigflag && pcursinvitem == -1 && !spselflag) {
 		infostr[0] = '\0';
 		infoclr = COL_WHITE;
@@ -1634,13 +1634,13 @@ void control_print_info_str(int y, char *str, BOOL center, int lines)
 	int strWidth, lineOffset, lineStart;
 
 	lineOffset = 0;
-	lineStart = lineOffsets[lines][y] + (SCREEN_WIDTH - PANEL_WIDTH) / 2;
+	lineStart = lineOffsets[lines][y] + PANEL_LEFT;
 	if (center == 1) {
 		strWidth = 0;
 		tmp = str;
 		while (*tmp) {
 			c = gbFontTransTbl[(BYTE)*tmp++];
-			strWidth += fontkern[fontframe[c]] + 1;
+			strWidth += fontkern[fontframe[c]] + 2;
 		}
 		if (strWidth < 288)
 			lineOffset = (288 - strWidth) >> 1;
@@ -1943,13 +1943,13 @@ void MY_PlrStringXY(int x, int y, int width, char *pszStr, char col, int base)
 
 void CheckLvlBtn()
 {
-	if (!lvlbtndown && MouseX >= 40 && MouseX <= 81 && MouseY >= 313 && MouseY <= 335)
+	if (!lvlbtndown && MouseX >= 40 + PANEL_LEFT && MouseX <= 81 + PANEL_LEFT && MouseY >= -39 + PANEL_TOP && MouseY <= -17 + PANEL_TOP)
 		lvlbtndown = TRUE;
 }
 
 void ReleaseLvlBtn()
 {
-	if (MouseX >= 40 && MouseX <= 81 && MouseY >= 313 && MouseY <= 335)
+	if (MouseX >= 40 + PANEL_LEFT && MouseX <= 81 + PANEL_LEFT && MouseY >= -39 + PANEL_TOP && MouseY <= -17 + PANEL_TOP)
 		chrflag = TRUE;
 	lvlbtndown = FALSE;
 }
@@ -1961,7 +1961,7 @@ void DrawLevelUpIcon()
 	if (!stextflag) {
 		nCel = lvlbtndown ? 3 : 2;
 		ADD_PlrStringXY(0, 303, 120, "Level Up", COL_WHITE);
-		CelDraw(40 + SCREEN_X, 335 + SCREEN_Y, pChrButtons, nCel, 41);
+		CelDraw(40 + PANEL_X, -17 + PANEL_Y, pChrButtons, nCel, 41);
 	}
 }
 
@@ -2044,9 +2044,9 @@ void DrawDurIcon()
 	int x1, x2, x3, x4;
 
 	if (!chrflag && !questlog || !invflag && !sbookflag) {
-		x1 = 656;
+		x1 = 592 + PANEL_X;
 		if (invflag || sbookflag)
-			x1 = 336;
+			x1 = 272 + PANEL_X;
 		p = &plr[myplr];
 		x2 = DrawDurIcon4Item(&p->InvBody[INVLOC_HEAD], x1, 4);
 		x3 = DrawDurIcon4Item(&p->InvBody[INVLOC_CHEST], x2, 3);
@@ -2086,7 +2086,7 @@ int DrawDurIcon4Item(ItemStruct *pItem, int x, int c)
 	}
 	if (pItem->_iDurability > 2)
 		c += 8;
-	CelDraw(x, 335 + SCREEN_Y, pDurIcons, c, 32);
+	CelDraw(x, -17 + PANEL_Y, pDurIcons, c, 32);
 	return x - 40;
 }
 
@@ -2198,8 +2198,8 @@ void DrawSpellBook()
 	char st;
 	unsigned __int64 spl;
 
-	CelDraw(PANEL_RIGHT, 351 + SCREEN_Y, pSpellBkCel, 1, 320);
-	CelDraw(PANEL_RIGHT + 76 * sbooktab + 7, 348 + SCREEN_Y, pSBkBtnCel, sbooktab + 1, 76);
+	CelDraw(RIGHT_PANEL_X, 351 + SCREEN_Y, pSpellBkCel, 1, 320);
+	CelDraw(RIGHT_PANEL_X + 76 * sbooktab + 7, 348 + SCREEN_Y, pSBkBtnCel, sbooktab + 1, 76);
 
 	spl = plr[myplr]._pMemSpells | plr[myplr]._pISpells | plr[myplr]._pAblSpells;
 
@@ -2209,10 +2209,10 @@ void DrawSpellBook()
 		if (sn != -1 && spl & (__int64)1 << (sn - 1)) {
 			st = GetSBookTrans(sn, TRUE);
 			SetSpellTrans(st);
-			DrawSpellCel(SCREEN_WIDTH - 320 + 75, yp, pSBkIconCels, SpellITbl[sn], 37);
+			DrawSpellCel(RIGHT_PANEL + 75, yp, pSBkIconCels, SpellITbl[sn], 37);
 			if (sn == plr[myplr]._pRSpell && st == plr[myplr]._pRSplType) {
 				SetSpellTrans(RSPLTYPE_SKILL);
-				DrawSpellCel(SCREEN_WIDTH - 320 + 75, yp, pSBkIconCels, 43, 37);
+				DrawSpellCel(RIGHT_PANEL + 75, yp, pSBkIconCels, 43, 37);
 			}
 			PrintSBookStr(10, yp - 23, FALSE, spelldata[sn].sNameText, COL_WHITE);
 			switch (GetSBookTrans(sn, FALSE)) {
@@ -2257,7 +2257,7 @@ void PrintSBookStr(int x, int y, BOOL cjustflag, char *pszStr, char col)
 	char *tmp;
 	int screen_x, line, width;
 
-	width = PitchTbl[y] + x + SCREEN_WIDTH - 320 + 120;
+	width = PitchTbl[y] + x + RIGHT_PANEL + 120;
 	line = 0;
 	if (cjustflag) {
 		screen_x = 0;
@@ -2288,7 +2288,7 @@ void CheckSBook()
 	char st;
 	unsigned __int64 spl;
 
-	if (MouseX >= 331 && MouseX < 368 && MouseY >= 18 && MouseY < 314) {
+	if (MouseX >= RIGHT_PANEL + 11 && MouseX < RIGHT_PANEL + 48 && MouseY >= 18 && MouseY < 314) {
 		spl = plr[myplr]._pMemSpells | plr[myplr]._pISpells | plr[myplr]._pAblSpells;
 		sn = SpellPages[sbooktab][(MouseY - 18) / 43];
 		if (sn != -1 && spl & (__int64)1 << (sn - 1)) {
@@ -2304,8 +2304,8 @@ void CheckSBook()
 			drawpanflag = 255;
 		}
 	}
-	if (MouseX >= 327 && MouseX < 633 && MouseY >= 320 && MouseY < 349) { /// BUGFIX: change `< 633` to `< 631`
-		sbooktab = (MouseX - 327) / 76;
+	if (MouseX >= RIGHT_PANEL + 7 && MouseX < RIGHT_PANEL + 313 && MouseY >= 320 && MouseY < 349) { /// BUGFIX: change `< 313` to `< 311`
+		sbooktab = (MouseX - (RIGHT_PANEL + 7)) / 76;
 	}
 }
 
@@ -2428,20 +2428,20 @@ void DrawTalkPan()
 	if (!talkflag)
 		return;
 
-	DrawPanelBox(175, sgbPlrTalkTbl + 20, 294, 5, 239, 516);
+	DrawPanelBox(175, sgbPlrTalkTbl + 20, 294, 5, PANEL_X + 175, PANEL_Y + 4);
 	off = 0;
 	for (i = 293; i > 283; off++, i--) {
-		DrawPanelBox((off >> 1) + 175, sgbPlrTalkTbl + off + 25, i, 1, (off >> 1) + 239, off + 521);
+		DrawPanelBox((off >> 1) + 175, sgbPlrTalkTbl + off + 25, i, 1, (off >> 1) + PANEL_X + 175, off + PANEL_Y + 9);
 	}
-	DrawPanelBox(185, sgbPlrTalkTbl + 35, 274, 30, 249, 531);
-	DrawPanelBox(180, sgbPlrTalkTbl + 65, 284, 5, 244, 561);
+	DrawPanelBox(185, sgbPlrTalkTbl + 35, 274, 30, PANEL_X + 185, PANEL_Y + 19);
+	DrawPanelBox(180, sgbPlrTalkTbl + 65, 284, 5, PANEL_X + 180, PANEL_Y + 49);
 	for (i = 0; i < 10; i++) {
-		DrawPanelBox(180, sgbPlrTalkTbl + i + 70, i + 284, 1, 244, i + 566);
+		DrawPanelBox(180, sgbPlrTalkTbl + i + 70, i + 284, 1, PANEL_X + 180, i + PANEL_Y + 54);
 	}
-	DrawPanelBox(170, sgbPlrTalkTbl + 80, 310, 55, 234, 576);
+	DrawPanelBox(170, sgbPlrTalkTbl + 80, 310, 55, PANEL_X + 170, PANEL_Y + 64);
 	msg = sgszTalkMsg;
 	for (i = 0; i < 39; i += 13) {
-		msg = control_print_talk_msg(msg, 0, i, &x, 0);
+		msg = control_print_talk_msg(msg, 0 + PANEL_LEFT, i, &x, 0);
 		if (!msg)
 			break;
 	}
@@ -2460,7 +2460,7 @@ void DrawTalkPan()
 					nCel = 4;
 				else
 					nCel = 3;
-				CelDraw(172 + SCREEN_X, 436 + 18 * talk_btn + SCREEN_Y, pTalkBtns, nCel, 61);
+				CelDraw(172 + PANEL_X, 84 + 18 * talk_btn + PANEL_Y, pTalkBtns, nCel, 61);
 			}
 		} else {
 			color = COL_RED;
@@ -2470,10 +2470,10 @@ void DrawTalkPan()
 				nCel = 1;
 			if (talkbtndown[talk_btn])
 				nCel += 4;
-			CelDraw(172 + SCREEN_X, 436 + 18 * talk_btn + SCREEN_Y, pTalkBtns, nCel, 61);
+			CelDraw(172 + PANEL_X, 84 + 18 * talk_btn + PANEL_Y, pTalkBtns, nCel, 61);
 		}
 		if (plr[i].plractive) {
-			control_print_talk_msg(plr[i]._pName, 46, 60 + talk_btn * 18, &x, color);
+			control_print_talk_msg(plr[i]._pName, 46 + PANEL_LEFT, 60 + talk_btn * 18, &x, color);
 		}
 
 		talk_btn++;
@@ -2487,12 +2487,12 @@ char *control_print_talk_msg(char *msg, int x, int y, int *nOffset, int color)
 
 	x += 264;
 	width = x;
-	*nOffset = PitchTbl[y + 534] + x;
+	*nOffset = PitchTbl[y + 182 + PANEL_TOP] + x;
 	while (*msg) {
 
 		c = fontframe[gbFontTransTbl[(BYTE)*msg]];
 		width += fontkern[c] + 1;
-		if (width > 514)
+		if (width > 514 + PANEL_LEFT)
 			return msg;
 		msg++;
 		if (c) {
@@ -2510,20 +2510,20 @@ BOOL control_check_talk_btn()
 	if (!talkflag)
 		return FALSE;
 
-	if (MouseX < 172)
+	if (MouseX < 172 + PANEL_LEFT)
 		return FALSE;
-	if (MouseY < 421)
+	if (MouseY < 69 + PANEL_TOP)
 		return FALSE;
-	if (MouseX > 233)
+	if (MouseX > 233 + PANEL_LEFT)
 		return FALSE;
-	if (MouseY > 475)
+	if (MouseY > 123 + PANEL_TOP)
 		return FALSE;
 
 	for (i = 0; i < sizeof(talkbtndown) / sizeof(talkbtndown[0]); i++) {
 		talkbtndown[i] = FALSE;
 	}
 
-	talkbtndown[(MouseY - 421) / 18] = TRUE;
+	talkbtndown[(MouseY - (69 + PANEL_TOP)) / 18] = TRUE;
 
 	return TRUE;
 }
@@ -2535,8 +2535,8 @@ void control_release_talk_btn()
 	if (talkflag) {
 		for (i = 0; i < sizeof(talkbtndown) / sizeof(talkbtndown[0]); i++)
 			talkbtndown[i] = FALSE;
-		if (MouseX >= 172 && MouseY >= 421 && MouseX <= 233 && MouseY <= 475) {
-			off = (MouseY - 421) / 18;
+		if (MouseX >= 172 + PANEL_LEFT && MouseY >= 421 + PANEL_LEFT && MouseX <= -119 + PANEL_TOP && MouseY <= 123 + PANEL_TOP) {
+			off = (MouseY - (69 + PANEL_TOP)) / 18;
 
 			for (p = 0; p < MAX_PLRS && off != -1; p++) {
 				if (p != myplr)
diff --git a/Source/control.h b/Source/control.h
index 181be4c5d..abe93be5f 100644
--- a/Source/control.h
+++ b/Source/control.h
@@ -65,7 +65,7 @@ void AddPanelString(char *str, BOOL just);
 void ClearPanel();
 void DrawPanelBox(int x, int y, int w, int h, int sx, int sy);
 void InitPanelStr();
-void SetFlaskHeight(BYTE *pCelBuff, int min, int max, int c, int r);
+void SetFlaskHeight(BYTE *pCelBuff, int min, int max, int sx, int sy);
 void DrawFlask(BYTE *pCelBuff, int w, int nSrcOff, BYTE *pBuff, int nDstOff, int h);
 void DrawLifeFlask();
 void UpdateLifeFlask();
diff --git a/Source/cursor.cpp b/Source/cursor.cpp
index adc9075e7..b3d1d0c08 100644
--- a/Source/cursor.cpp
+++ b/Source/cursor.cpp
@@ -223,7 +223,7 @@ void CheckCursMove()
 	ty = sy >> 5;
 	px = sx & 0x3F;
 	py = sy & 0x1F;
-	mx = ViewX + tx + ty - (zoomflag ? 10 : 5);
+	mx = ViewX + tx + ty - (zoomflag ? (SCREEN_WIDTH / 64) : (SCREEN_WIDTH / 2 / 64));
 	my = ViewY + ty - tx;
 
 	flipy = py < (px >> 1);
@@ -278,14 +278,14 @@ void CheckCursMove()
 	if (doomflag) {
 		return;
 	}
-	if (invflag && MouseX > 320) {
+	if (invflag && MouseX > RIGHT_PANEL) {
 		pcursinvitem = CheckInvHLight();
 		return;
 	}
-	if (sbookflag && MouseX > 320) {
+	if (sbookflag && MouseX > RIGHT_PANEL) {
 		return;
 	}
-	if ((chrflag || questlog) && MouseX < 320) {
+	if ((chrflag || questlog) && MouseX < RIGHT_PANEL) {
 		return;
 	}
 
diff --git a/Source/diablo.cpp b/Source/diablo.cpp
index 010a976e7..203824312 100644
--- a/Source/diablo.cpp
+++ b/Source/diablo.cpp
@@ -794,10 +794,10 @@ BOOL LeftMouseDown(int wParam)
 						sfx_stop();
 					} else if (chrflag && MouseX < 320) {
 						CheckChrBtns();
-					} else if (invflag && MouseX > 320) {
+					} else if (invflag && MouseX > RIGHT_PANEL) {
 						if (!dropGoldFlag)
 							CheckInvItem();
-					} else if (sbookflag && MouseX > 320) {
+					} else if (sbookflag && MouseX > RIGHT_PANEL) {
 						CheckSBook();
 					} else if (pcurs >= CURSOR_FIRSTITEM) {
 						if (TryInvPut()) {
diff --git a/Source/error.cpp b/Source/error.cpp
index fd2df0a8c..557198b67 100644
--- a/Source/error.cpp
+++ b/Source/error.cpp
@@ -85,34 +85,34 @@ void DrawDiabloMsg()
 	int i, len, off, width, sx, sy;
 	BYTE c;
 
-	CelDraw(165, 318, pSTextSlidCels, 1, 12);
-	CelDraw(591, 318, pSTextSlidCels, 4, 12);
-	CelDraw(165, 366, pSTextSlidCels, 2, 12);
-	CelDraw(591, 366, pSTextSlidCels, 3, 12);
+	CelDraw(PANEL_X + 101, DIALOG_Y, pSTextSlidCels, 1, 12);
+	CelDraw(PANEL_X + 527, DIALOG_Y, pSTextSlidCels, 4, 12);
+	CelDraw(PANEL_X + 101, DIALOG_Y + 48, pSTextSlidCels, 2, 12);
+	CelDraw(PANEL_X + 527, DIALOG_Y + 48, pSTextSlidCels, 3, 12);
 
-	sx = 173;
+	sx = PANEL_X + 109;
 	for (i = 0; i < 35; i++) {
-		CelDraw(sx, 318, pSTextSlidCels, 5, 12);
-		CelDraw(sx, 366, pSTextSlidCels, 7, 12);
+		CelDraw(sx, DIALOG_Y, pSTextSlidCels, 5, 12);
+		CelDraw(sx, DIALOG_Y + 48, pSTextSlidCels, 7, 12);
 		sx += 12;
 	}
-	sy = 330;
+	sy = DIALOG_Y + 12;
 	for (i = 0; i < 3; i++) {
-		CelDraw(165, sy, pSTextSlidCels, 6, 12);
-		CelDraw(591, sy, pSTextSlidCels, 8, 12);
+		CelDraw(PANEL_X + 101, sy, pSTextSlidCels, 6, 12);
+		CelDraw(PANEL_X + 527, sy, pSTextSlidCels, 8, 12);
 		sy += 12;
 	}
 
 	/// ASSERT: assert(gpBuffer);
 
-#define TRANS_RECT_X 104
-#define TRANS_RECT_Y 150
+#define TRANS_RECT_X (PANEL_LEFT + 104)
+#define TRANS_RECT_Y (DIALOG_TOP - 8)
 #define TRANS_RECT_WIDTH 432
 #define TRANS_RECT_HEIGHT 54
 #include "asm_trans_rect.inc"
 
 	strcpy(tempstr, MsgStrings[msgflag]);
-	off = 165 + PitchTbl[342];
+	off = PANEL_X + 101 + PitchTbl[DIALOG_Y + 24];
 	len = strlen(tempstr);
 	width = 0;
 
diff --git a/Source/gmenu.cpp b/Source/gmenu.cpp
index b3f92f09b..314b58c2a 100644
--- a/Source/gmenu.cpp
+++ b/Source/gmenu.cpp
@@ -43,7 +43,7 @@ void gmenu_draw_pause()
 		RedBack();
 	if (!sgpCurrentMenu) {
 		light_table_index = 0;
-		gmenu_print_text(316, 336, "Pause");
+		gmenu_print_text(316 + PANEL_LEFT, -16 + PANEL_TOP, "Pause");
 	}
 }
 
@@ -179,14 +179,14 @@ void gmenu_draw_menu_item(TMenuItem *pItem, int y)
 	w = gmenu_get_lfont(pItem);
 	if (pItem->dwFlags & GMENU_SLIDER) {
 		x = 16 + w / 2 + SCREEN_X;
-		CelDraw(x, t - 8, optbar_cel, 1, 287);
+		CelDraw(x + PANEL_LEFT, t - 8, optbar_cel, 1, 287);
 		step = pItem->dwFlags & 0xFFF;
 		nSteps = (pItem->dwFlags & 0xFFF000) >> 12;
 		if (nSteps < 2)
 			nSteps = 2;
 		pos = step * 256 / nSteps;
-		gmenu_clear_buffer(x + 2, t - 10, pos + 13, 28);
-		CelDraw(x + 2 + pos, y - 12, option_cel, 1, 27);
+		gmenu_clear_buffer(x + 2 + PANEL_LEFT, t - 10, pos + 13, 28);
+		CelDraw(x + 2 + pos + PANEL_LEFT, y - 12, option_cel, 1, 27);
 	}
 	x = SCREEN_WIDTH / 2 - w / 2 + SCREEN_X;
 	light_table_index = (pItem->dwFlags & GMENU_ENABLED) ? 0 : 15;
@@ -299,15 +299,15 @@ BOOL gmenu_on_mouse_move()
 BOOLEAN gmenu_valid_mouse_pos(int *plOffset)
 {
 	*plOffset = 282;
-	if (MouseX < 282) {
+	if (MouseX < 282 + PANEL_LEFT) {
 		*plOffset = 0;
 		return 0;
 	}
-	if (MouseX > 538) {
+	if (MouseX > 538 + PANEL_LEFT) {
 		*plOffset = 256;
 		return 0;
 	}
-	*plOffset = MouseX - 282;
+	*plOffset = MouseX - 282 - PANEL_LEFT;
 	return 1;
 }
 
diff --git a/Source/help.cpp b/Source/help.cpp
index acd016417..5d6ed9401 100644
--- a/Source/help.cpp
+++ b/Source/help.cpp
@@ -537,7 +537,7 @@ void DrawHelpLine(int always_0, int help_line_nr, char *text, char color)
 	BYTE c;
 
 	width = 0;
-	off = PitchTbl[SStringY[help_line_nr] + 204] + always_0 + 96;
+	off = PitchTbl[SStringY[help_line_nr] + 204] + always_0 + 96 + PANEL_LEFT;
 	while (*text) {
 		c = gbFontTransTbl[(BYTE)*text];
 		text++;
diff --git a/Source/inv.cpp b/Source/inv.cpp
index 4928b7b82..fb65cf7ec 100644
--- a/Source/inv.cpp
+++ b/Source/inv.cpp
@@ -8,79 +8,79 @@ int sgdwLastTime; // check name
 const InvXY InvRect[73] = {
 	// clang-format off
 	//  X,   Y
-	{ 452,  31 }, // helmet
-	{ 480,  31 }, // helmet
-	{ 452,  59 }, // helmet
-	{ 480,  59 }, // helmet
-	{ 365, 205 }, // left ring
-	{ 567, 205 }, // right ring
-	{ 524,  59 }, // amulet
-	{ 337, 104 }, // left hand
-	{ 366, 104 }, // left hand
-	{ 337, 132 }, // left hand
-	{ 366, 132 }, // left hand
-	{ 337, 160 }, // left hand
-	{ 366, 160 }, // left hand
-	{ 567, 104 }, // right hand
-	{ 596, 104 }, // right hand
-	{ 567, 132 }, // right hand
-	{ 596, 132 }, // right hand
-	{ 567, 160 }, // right hand
-	{ 596, 160 }, // right hand
-	{ 452, 104 }, // chest
-	{ 480, 104 }, // chest
-	{ 452, 132 }, // chest
-	{ 480, 132 }, // chest
-	{ 452, 160 }, // chest
-	{ 480, 160 }, // chest
-	{ 337, 250 }, // inv row 1
-	{ 366, 250 }, // inv row 1
-	{ 394, 250 }, // inv row 1
-	{ 423, 250 }, // inv row 1
-	{ 451, 250 }, // inv row 1
-	{ 480, 250 }, // inv row 1
-	{ 509, 250 }, // inv row 1
-	{ 538, 250 }, // inv row 1
-	{ 567, 250 }, // inv row 1
-	{ 596, 250 }, // inv row 1
-	{ 337, 279 }, // inv row 2
-	{ 366, 279 }, // inv row 2
-	{ 394, 279 }, // inv row 2
-	{ 423, 279 }, // inv row 2
-	{ 451, 279 }, // inv row 2
-	{ 480, 279 }, // inv row 2
-	{ 509, 279 }, // inv row 2
-	{ 538, 279 }, // inv row 2
-	{ 567, 279 }, // inv row 2
-	{ 596, 279 }, // inv row 2
-	{ 337, 308 }, // inv row 3
-	{ 366, 308 }, // inv row 3
-	{ 394, 308 }, // inv row 3
-	{ 423, 308 }, // inv row 3
-	{ 451, 308 }, // inv row 3
-	{ 480, 308 }, // inv row 3
-	{ 509, 308 }, // inv row 3
-	{ 538, 308 }, // inv row 3
-	{ 567, 308 }, // inv row 3
-	{ 596, 308 }, // inv row 3
-	{ 337, 336 }, // inv row 4
-	{ 366, 336 }, // inv row 4
-	{ 394, 336 }, // inv row 4
-	{ 423, 336 }, // inv row 4
-	{ 451, 336 }, // inv row 4
-	{ 480, 336 }, // inv row 4
-	{ 509, 336 }, // inv row 4
-	{ 538, 336 }, // inv row 4
-	{ 567, 336 }, // inv row 4
-	{ 596, 336 }, // inv row 4
-	{ 205, 385 }, // belt
-	{ 234, 385 }, // belt
-	{ 263, 385 }, // belt
-	{ 292, 385 }, // belt
-	{ 321, 385 }, // belt
-	{ 350, 385 }, // belt
-	{ 379, 385 }, // belt
-	{ 408, 385 }  // belt
+	{ RIGHT_PANEL + 132,  31 }, // helmet
+	{ RIGHT_PANEL + 160,  31 }, // helmet
+	{ RIGHT_PANEL + 132,  59 }, // helmet
+	{ RIGHT_PANEL + 160,  59 }, // helmet
+	{ RIGHT_PANEL + 45,  205 }, // left ring
+	{ RIGHT_PANEL + 247, 205 }, // right ring
+	{ RIGHT_PANEL + 204,  59 }, // amulet
+	{ RIGHT_PANEL + 17,  104 }, // left hand
+	{ RIGHT_PANEL + 46,  104 }, // left hand
+	{ RIGHT_PANEL + 17,  132 }, // left hand
+	{ RIGHT_PANEL + 46,  132 }, // left hand
+	{ RIGHT_PANEL + 17,  160 }, // left hand
+	{ RIGHT_PANEL + 46,  160 }, // left hand
+	{ RIGHT_PANEL + 247, 104 }, // right hand
+	{ RIGHT_PANEL + 276, 104 }, // right hand
+	{ RIGHT_PANEL + 247, 132 }, // right hand
+	{ RIGHT_PANEL + 276, 132 }, // right hand
+	{ RIGHT_PANEL + 247, 160 }, // right hand
+	{ RIGHT_PANEL + 276, 160 }, // right hand
+	{ RIGHT_PANEL + 132, 104 }, // chest
+	{ RIGHT_PANEL + 160, 104 }, // chest
+	{ RIGHT_PANEL + 132, 132 }, // chest
+	{ RIGHT_PANEL + 160, 132 }, // chest
+	{ RIGHT_PANEL + 132, 160 }, // chest
+	{ RIGHT_PANEL + 160, 160 }, // chest
+	{ RIGHT_PANEL + 17,  250 }, // inv row 1
+	{ RIGHT_PANEL + 46,  250 }, // inv row 1
+	{ RIGHT_PANEL + 74,  250 }, // inv row 1
+	{ RIGHT_PANEL + 103, 250 }, // inv row 1
+	{ RIGHT_PANEL + 131, 250 }, // inv row 1
+	{ RIGHT_PANEL + 160, 250 }, // inv row 1
+	{ RIGHT_PANEL + 189, 250 }, // inv row 1
+	{ RIGHT_PANEL + 218, 250 }, // inv row 1
+	{ RIGHT_PANEL + 247, 250 }, // inv row 1
+	{ RIGHT_PANEL + 276, 250 }, // inv row 1
+	{ RIGHT_PANEL + 17,  279 }, // inv row 2
+	{ RIGHT_PANEL + 46,  279 }, // inv row 2
+	{ RIGHT_PANEL + 74,  279 }, // inv row 2
+	{ RIGHT_PANEL + 103, 279 }, // inv row 2
+	{ RIGHT_PANEL + 131, 279 }, // inv row 2
+	{ RIGHT_PANEL + 160, 279 }, // inv row 2
+	{ RIGHT_PANEL + 189, 279 }, // inv row 2
+	{ RIGHT_PANEL + 218, 279 }, // inv row 2
+	{ RIGHT_PANEL + 247, 279 }, // inv row 2
+	{ RIGHT_PANEL + 276, 279 }, // inv row 2
+	{ RIGHT_PANEL + 17,  308 }, // inv row 3
+	{ RIGHT_PANEL + 46,  308 }, // inv row 3
+	{ RIGHT_PANEL + 74,  308 }, // inv row 3
+	{ RIGHT_PANEL + 103, 308 }, // inv row 3
+	{ RIGHT_PANEL + 131, 308 }, // inv row 3
+	{ RIGHT_PANEL + 160, 308 }, // inv row 3
+	{ RIGHT_PANEL + 189, 308 }, // inv row 3
+	{ RIGHT_PANEL + 218, 308 }, // inv row 3
+	{ RIGHT_PANEL + 247, 308 }, // inv row 3
+	{ RIGHT_PANEL + 276, 308 }, // inv row 3
+	{ RIGHT_PANEL + 17,  336 }, // inv row 4
+	{ RIGHT_PANEL + 46,  336 }, // inv row 4
+	{ RIGHT_PANEL + 74,  336 }, // inv row 4
+	{ RIGHT_PANEL + 103, 336 }, // inv row 4
+	{ RIGHT_PANEL + 131, 336 }, // inv row 4
+	{ RIGHT_PANEL + 160, 336 }, // inv row 4
+	{ RIGHT_PANEL + 189, 336 }, // inv row 4
+	{ RIGHT_PANEL + 218, 336 }, // inv row 4
+	{ RIGHT_PANEL + 247, 336 }, // inv row 4
+	{ RIGHT_PANEL + 276, 336 }, // inv row 4
+	{ PANEL_LEFT + 205, PANEL_TOP + 33 }, // belt
+	{ PANEL_LEFT + 234, PANEL_TOP + 33 }, // belt
+	{ PANEL_LEFT + 263, PANEL_TOP + 33 }, // belt
+	{ PANEL_LEFT + 292, PANEL_TOP + 33 }, // belt
+	{ PANEL_LEFT + 321, PANEL_TOP + 33 }, // belt
+	{ PANEL_LEFT + 350, PANEL_TOP + 33 }, // belt
+	{ PANEL_LEFT + 379, PANEL_TOP + 33 }, // belt
+	{ PANEL_LEFT + 408, PANEL_TOP + 33 }  // belt
 	// clang-format on
 };
 
@@ -172,10 +172,10 @@ void DrawInv()
 	BOOL invtest[NUM_INV_GRID_ELEM];
 	int frame, frame_width, colour, screen_x, screen_y, i, j, ii;
 
-	CelDraw(PANEL_RIGHT, 351 + SCREEN_Y, pInvCels, 1, 320);
+	CelDraw(RIGHT_PANEL_X, 351 + SCREEN_Y, pInvCels, 1, 320);
 
 	if (plr[myplr].InvBody[INVLOC_HEAD]._itype != ITYPE_NONE) {
-		InvDrawSlotBack(PANEL_RIGHT + 133, 59 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 2 * INV_SLOT_SIZE_PX);
+		InvDrawSlotBack(RIGHT_PANEL_X + 133, 59 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 2 * INV_SLOT_SIZE_PX);
 
 		frame = plr[myplr].InvBody[INVLOC_HEAD]._iCurs + CURSOR_FIRSTITEM;
 		frame_width = InvItemWidth[frame];
@@ -188,18 +188,18 @@ void DrawInv()
 			if (!plr[myplr].InvBody[INVLOC_HEAD]._iStatFlag) {
 				colour = ICOL_RED;
 			}
-			CelBlitOutline(colour, PANEL_RIGHT + 133, 59 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelBlitOutline(colour, RIGHT_PANEL_X + 133, 59 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		}
 
 		if (plr[myplr].InvBody[INVLOC_HEAD]._iStatFlag) {
-			CelClippedDraw(PANEL_RIGHT + 133, 59 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelClippedDraw(RIGHT_PANEL_X + 133, 59 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		} else {
-			CelDrawLightRed(PANEL_RIGHT + 133, 59 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
+			CelDrawLightRed(RIGHT_PANEL_X + 133, 59 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
 		}
 	}
 
 	if (plr[myplr].InvBody[INVLOC_RING_LEFT]._itype != ITYPE_NONE) {
-		InvDrawSlotBack(PANEL_RIGHT + 48, 205 + SCREEN_Y, INV_SLOT_SIZE_PX, INV_SLOT_SIZE_PX);
+		InvDrawSlotBack(RIGHT_PANEL_X + 48, 205 + SCREEN_Y, INV_SLOT_SIZE_PX, INV_SLOT_SIZE_PX);
 
 		frame = plr[myplr].InvBody[INVLOC_RING_LEFT]._iCurs + CURSOR_FIRSTITEM;
 		frame_width = InvItemWidth[frame];
@@ -212,18 +212,18 @@ void DrawInv()
 			if (!plr[myplr].InvBody[INVLOC_RING_LEFT]._iStatFlag) {
 				colour = ICOL_RED;
 			}
-			CelBlitOutline(colour, PANEL_RIGHT + 48, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelBlitOutline(colour, RIGHT_PANEL_X + 48, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		}
 
 		if (plr[myplr].InvBody[INVLOC_RING_LEFT]._iStatFlag) {
-			CelClippedDraw(PANEL_RIGHT + 48, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelClippedDraw(RIGHT_PANEL_X + 48, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		} else {
-			CelDrawLightRed(PANEL_RIGHT + 48, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
+			CelDrawLightRed(RIGHT_PANEL_X + 48, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
 		}
 	}
 
 	if (plr[myplr].InvBody[INVLOC_RING_RIGHT]._itype != ITYPE_NONE) {
-		InvDrawSlotBack(PANEL_RIGHT + 249, 205 + SCREEN_Y, INV_SLOT_SIZE_PX, INV_SLOT_SIZE_PX);
+		InvDrawSlotBack(RIGHT_PANEL_X + 249, 205 + SCREEN_Y, INV_SLOT_SIZE_PX, INV_SLOT_SIZE_PX);
 
 		frame = plr[myplr].InvBody[INVLOC_RING_RIGHT]._iCurs + CURSOR_FIRSTITEM;
 		frame_width = InvItemWidth[frame];
@@ -236,18 +236,18 @@ void DrawInv()
 			if (!plr[myplr].InvBody[INVLOC_RING_RIGHT]._iStatFlag) {
 				colour = ICOL_RED;
 			}
-			CelBlitOutline(colour, PANEL_RIGHT + 249, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelBlitOutline(colour, RIGHT_PANEL_X + 249, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		}
 
 		if (plr[myplr].InvBody[INVLOC_RING_RIGHT]._iStatFlag) {
-			CelClippedDraw(PANEL_RIGHT + 249, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelClippedDraw(RIGHT_PANEL_X + 249, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		} else {
-			CelDrawLightRed(PANEL_RIGHT + 249, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
+			CelDrawLightRed(RIGHT_PANEL_X + 249, 205 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
 		}
 	}
 
 	if (plr[myplr].InvBody[INVLOC_AMULET]._itype != ITYPE_NONE) {
-		InvDrawSlotBack(PANEL_RIGHT + 205, 60 + SCREEN_Y, INV_SLOT_SIZE_PX, INV_SLOT_SIZE_PX);
+		InvDrawSlotBack(RIGHT_PANEL_X + 205, 60 + SCREEN_Y, INV_SLOT_SIZE_PX, INV_SLOT_SIZE_PX);
 
 		frame = plr[myplr].InvBody[INVLOC_AMULET]._iCurs + CURSOR_FIRSTITEM;
 		frame_width = InvItemWidth[frame];
@@ -260,23 +260,23 @@ void DrawInv()
 			if (!plr[myplr].InvBody[INVLOC_AMULET]._iStatFlag) {
 				colour = ICOL_RED;
 			}
-			CelBlitOutline(colour, PANEL_RIGHT + 205, 60 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelBlitOutline(colour, RIGHT_PANEL_X + 205, 60 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		}
 
 		if (plr[myplr].InvBody[INVLOC_AMULET]._iStatFlag) {
-			CelClippedDraw(PANEL_RIGHT + 205, 60 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelClippedDraw(RIGHT_PANEL_X + 205, 60 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		} else {
-			CelDrawLightRed(PANEL_RIGHT + 205, 60 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
+			CelDrawLightRed(RIGHT_PANEL_X + 205, 60 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
 		}
 	}
 
 	if (plr[myplr].InvBody[INVLOC_HAND_LEFT]._itype != ITYPE_NONE) {
-		InvDrawSlotBack(PANEL_RIGHT + 17, 160 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 3 * INV_SLOT_SIZE_PX);
+		InvDrawSlotBack(RIGHT_PANEL_X + 17, 160 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 3 * INV_SLOT_SIZE_PX);
 
 		frame = plr[myplr].InvBody[INVLOC_HAND_LEFT]._iCurs + CURSOR_FIRSTITEM;
 		frame_width = InvItemWidth[frame];
 		// calc item offsets for weapons smaller than 2x3 slots
-		screen_x = frame_width == INV_SLOT_SIZE_PX ? (PANEL_RIGHT + 31) : (PANEL_RIGHT + 17);
+		screen_x = frame_width == INV_SLOT_SIZE_PX ? (RIGHT_PANEL_X + 31) : (RIGHT_PANEL_X + 17);
 		screen_y = InvItemHeight[frame] == (3 * INV_SLOT_SIZE_PX) ? (160 + SCREEN_Y) : (146 + SCREEN_Y);
 
 		if (pcursinvitem == INVITEM_HAND_LEFT) {
@@ -297,26 +297,26 @@ void DrawInv()
 		}
 
 		if (plr[myplr].InvBody[INVLOC_HAND_LEFT]._iLoc == ILOC_TWOHAND) {
-			InvDrawSlotBack(PANEL_RIGHT + 247, 160 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 3 * INV_SLOT_SIZE_PX);
+			InvDrawSlotBack(RIGHT_PANEL_X + 247, 160 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 3 * INV_SLOT_SIZE_PX);
 			light_table_index = 0;
 			cel_transparency_active = 1;
 
 			CelClippedBlitLightTrans(
 			    frame_width == INV_SLOT_SIZE_PX
-			        ? &gpBuffer[SCREENXY(PANEL_RIGHT + 197, SCREEN_Y)]
-			        : &gpBuffer[SCREENXY(PANEL_RIGHT + 183, SCREEN_Y)],
+			        ? &gpBuffer[SCREENXY(RIGHT_PANEL_X + 197, SCREEN_Y)]
+			        : &gpBuffer[SCREENXY(RIGHT_PANEL_X + 183, SCREEN_Y)],
 			    pCursCels, frame, frame_width, 0, 8);
 
 			cel_transparency_active = 0;
 		}
 	}
 	if (plr[myplr].InvBody[INVLOC_HAND_RIGHT]._itype != ITYPE_NONE) {
-		InvDrawSlotBack(PANEL_RIGHT + 247, 160 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 3 * INV_SLOT_SIZE_PX);
+		InvDrawSlotBack(RIGHT_PANEL_X + 247, 160 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 3 * INV_SLOT_SIZE_PX);
 
 		frame = plr[myplr].InvBody[INVLOC_HAND_RIGHT]._iCurs + CURSOR_FIRSTITEM;
 		frame_width = InvItemWidth[frame];
 		// calc item offsets for weapons smaller than 2x3 slots
-		screen_x = frame_width == INV_SLOT_SIZE_PX ? (PANEL_RIGHT + 261) : (PANEL_RIGHT + 249);
+		screen_x = frame_width == INV_SLOT_SIZE_PX ? (RIGHT_PANEL_X + 261) : (RIGHT_PANEL_X + 249);
 		screen_y = InvItemHeight[frame] == 3 * INV_SLOT_SIZE_PX ? (160 + SCREEN_Y) : (146 + SCREEN_Y);
 
 		if (pcursinvitem == INVITEM_HAND_RIGHT) {
@@ -338,7 +338,7 @@ void DrawInv()
 	}
 
 	if (plr[myplr].InvBody[INVLOC_CHEST]._itype != ITYPE_NONE) {
-		InvDrawSlotBack(PANEL_RIGHT + 133, 160 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 3 * INV_SLOT_SIZE_PX);
+		InvDrawSlotBack(RIGHT_PANEL_X + 133, 160 + SCREEN_Y, 2 * INV_SLOT_SIZE_PX, 3 * INV_SLOT_SIZE_PX);
 
 		frame = plr[myplr].InvBody[INVLOC_CHEST]._iCurs + CURSOR_FIRSTITEM;
 		frame_width = InvItemWidth[frame];
@@ -351,13 +351,13 @@ void DrawInv()
 			if (!plr[myplr].InvBody[INVLOC_CHEST]._iStatFlag) {
 				colour = ICOL_RED;
 			}
-			CelBlitOutline(colour, PANEL_RIGHT + 133, 160 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelBlitOutline(colour, RIGHT_PANEL_X + 133, 160 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		}
 
 		if (plr[myplr].InvBody[INVLOC_CHEST]._iStatFlag) {
-			CelClippedDraw(PANEL_RIGHT + 133, 160 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
+			CelClippedDraw(RIGHT_PANEL_X + 133, 160 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8);
 		} else {
-			CelDrawLightRed(PANEL_RIGHT + 133, 160 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
+			CelDrawLightRed(RIGHT_PANEL_X + 133, 160 + SCREEN_Y, pCursCels, frame, frame_width, 0, 8, 1);
 		}
 	}
 
@@ -419,7 +419,7 @@ void DrawInvBelt()
 		return;
 	}
 
-	DrawPanelBox(205, 21, 232, 28, 269, 517);
+	DrawPanelBox(205, 21, 232, 28, PANEL_X + 205, PANEL_Y + 5);
 
 	for (i = 0; i < MAXBELTITEMS; i++) {
 		if (plr[myplr].SpdList[i]._itype == ITYPE_NONE) {
@@ -1359,8 +1359,8 @@ void CheckInvItem()
  */
 void CheckInvScrn()
 {
-	if (MouseX > 190 && MouseX < 437
-	    && MouseY > PANEL_TOP && MouseY < 385) {
+	if (MouseX > 190 + PANEL_LEFT && MouseX < 437 + PANEL_LEFT
+	    && MouseY > PANEL_TOP && MouseY < 33 + PANEL_TOP) {
 		CheckInvItem();
 	}
 }
diff --git a/Source/minitext.cpp b/Source/minitext.cpp
index e7adc0f5e..4ad8bee65 100644
--- a/Source/minitext.cpp
+++ b/Source/minitext.cpp
@@ -69,7 +69,7 @@ void InitQTextMsg(int m)
 
 void DrawQTextBack()
 {
-	CelDraw(88, 487, pTextBoxCels, 1, 591);
+	CelDraw(PANEL_X + 24, 487, pTextBoxCels, 1, 591);
 
 #define TRANS_RECT_X 27
 #define TRANS_RECT_Y 28
diff --git a/Source/player.cpp b/Source/player.cpp
index 4ce8d5f3e..1d7dba16f 100644
--- a/Source/player.cpp
+++ b/Source/player.cpp
@@ -3663,7 +3663,7 @@ void CheckPlrSpell()
 
 	if (pcurs != CURSOR_HAND
 	    || MouseY >= PANEL_TOP
-	    || (chrflag && MouseX < 320 || invflag && MouseX > 320)
+	    || (chrflag && MouseX < 320 || invflag && MouseX > RIGHT_PANEL)
 	        && rspell != SPL_HEAL
 	        && rspell != SPL_IDENTIFY
 	        && rspell != SPL_REPAIR
diff --git a/Source/scrollrt.cpp b/Source/scrollrt.cpp
index cae1da70b..9238a4738 100644
--- a/Source/scrollrt.cpp
+++ b/Source/scrollrt.cpp
@@ -2085,24 +2085,24 @@ static void DrawGame(int x, int y)
 	dword_5C2FF8 = SCREEN_WIDTH / 64;
 	dword_5C2FFC = VIEWPORT_HEIGHT / 32;
 
-	sx = ScrollInfo._sxoff + 64;
-	sy = ScrollInfo._syoff + 175;
-	x -= 10;
+	sx = ScrollInfo._sxoff + SCREEN_X;
+	sy = ScrollInfo._syoff + SCREEN_Y + 15;
+	x -= SCREEN_WIDTH / 64;
 	y--;
-	chunks = 10;
+	chunks = SCREEN_WIDTH / 64;
 	blocks = 8;
 
 	if (chrflag || questlog) {
 		x += 2;
 		y -= 2;
-		sx += 288;
-		chunks = 6;
+		sx += (SCREEN_WIDTH / 2) - 32;
+		chunks = (SCREEN_WIDTH / 64) - 4;
 	}
 	if (invflag || sbookflag) {
 		x += 2;
 		y -= 2;
 		sx -= 32;
-		chunks = 6;
+		chunks = (SCREEN_WIDTH / 64) - 4;
 	}
 
 	switch (ScrollInfo._sdir) {
@@ -2189,15 +2189,15 @@ static void DrawZoom(int x, int y)
 	int wdt, nSrcOff, nDstOff;
 
 	scr_pix_width = ZOOM_WIDTH;
-	scr_pix_height = 192;
+	scr_pix_height = ZOOM_HEIGHT - 32;
 	dword_5C2FF8 = ZOOM_WIDTH / 64;
-	dword_5C2FFC = 192 / 32;
+	dword_5C2FFC = (ZOOM_HEIGHT - 32) / 32;
 
-	sx = ScrollInfo._sxoff + 64;
-	sy = ScrollInfo._syoff + 143;
-	x -= 6;
+	sx = ScrollInfo._sxoff + SCREEN_X;
+	sy = ScrollInfo._syoff + SCREEN_Y - 17;
+	x -= ZOOM_WIDTH / 64;
 	y--;
-	chunks = 6;
+	chunks = ZOOM_WIDTH / 64;
 	blocks = 3;
 
 	switch (ScrollInfo._sdir) {
diff --git a/Source/stores.cpp b/Source/stores.cpp
index 686b4ce0e..fd6bae1cd 100644
--- a/Source/stores.cpp
+++ b/Source/stores.cpp
@@ -130,7 +130,7 @@ void FreeStoreMem()
 
 void DrawSTextBack()
 {
-	CelDraw(408, 487, pSTextBoxCels, 1, 271);
+	CelDraw(PANEL_X + 344, 487, pSTextBoxCels, 1, 271);
 
 #define TRANS_RECT_X 347
 #define TRANS_RECT_Y 28
@@ -148,9 +148,9 @@ void PrintSString(int x, int y, BOOL cjustflag, char *str, char col, int val)
 
 	s = SStringY[y] + stext[y]._syoff;
 	if (stextsize)
-		xx = 96;
+		xx = PANEL_X + 32;
 	else
-		xx = 416;
+		xx = PANEL_X + 352;
 	off = xx + x + PitchTbl[s + 204];
 	len = strlen(str);
 	if (stextsize)
@@ -248,16 +248,16 @@ void DrawSArrows(int y1, int y2)
 	yd1 = SStringY[y1] + 204;
 	yd2 = SStringY[y2] + 204;
 	if (stextscrlubtn != -1)
-		CelDraw(665, yd1, pSTextSlidCels, 12, 12);
+		CelDraw(PANEL_X + 601, yd1, pSTextSlidCels, 12, 12);
 	else
-		CelDraw(665, yd1, pSTextSlidCels, 10, 12);
+		CelDraw(PANEL_X + 601, yd1, pSTextSlidCels, 10, 12);
 	if (stextscrldbtn != -1)
-		CelDraw(665, yd2, pSTextSlidCels, 11, 12);
+		CelDraw(PANEL_X + 601, yd2, pSTextSlidCels, 11, 12);
 	else
-		CelDraw(665, yd2, pSTextSlidCels, 9, 12);
+		CelDraw(PANEL_X + 601, yd2, pSTextSlidCels, 9, 12);
 	yd1 += 12;
 	for (yd3 = yd1; yd3 < yd2; yd3 += 12) {
-		CelDraw(665, yd3, pSTextSlidCels, 14, 12);
+		CelDraw(PANEL_X + 601, yd3, pSTextSlidCels, 14, 12);
 	}
 	if (stextsel == 22)
 		yd3 = stextlhold;
@@ -267,7 +267,7 @@ void DrawSArrows(int y1, int y2)
 		yd3 = 1000 * (stextsval + ((yd3 - stextup) >> 2)) / (storenumh - 1) * (SStringY[y2] - SStringY[y1] - 24) / 1000;
 	else
 		yd3 = 0;
-	CelDraw(665, SStringY[y1 + 1] + 204 + yd3, pSTextSlidCels, 13, 12);
+	CelDraw(PANEL_X + 601, SStringY[y1 + 1] + 204 + yd3, pSTextSlidCels, 13, 12);
 }
 
 void DrawSTextHelp()
@@ -2765,14 +2765,14 @@ void CheckStoreBtn()
 			sfx_stop();
 	} else if (stextsel != -1 && MouseY >= 32 && MouseY <= 320) {
 		if (!stextsize) {
-			if (MouseX < 344 || MouseX > 616)
+			if (MouseX < 344 + PANEL_LEFT || MouseX > 616 + PANEL_LEFT)
 				return;
 		} else {
-			if (MouseX < 24 || MouseX > 616)
+			if (MouseX < 24 + PANEL_LEFT || MouseX > 616 + PANEL_LEFT)
 				return;
 		}
 		y = (MouseY - 32) / 12;
-		if (stextscrl && MouseX > 600) {
+		if (stextscrl && MouseX > 600 + PANEL_LEFT) {
 			if (y == 4) {
 				if (stextscrlubtn <= 0) {
 					STextUp();
diff --git a/Source/town.cpp b/Source/town.cpp
index 4fed3ed10..de4ae49b6 100644
--- a/Source/town.cpp
+++ b/Source/town.cpp
@@ -1056,15 +1056,15 @@ void T_DrawGame(int x, int y)
 
 	sx = ScrollInfo._sxoff + 64;
 	sy = ScrollInfo._syoff + 175;
-	x -= 10;
+	x -= SCREEN_WIDTH / 64;
 	y--;
-	chunks = 10;
+	chunks = SCREEN_WIDTH / 64;
 	blocks = 5;
 
 	if (chrflag || questlog) {
 		x += 2;
 		y -= 2;
-		sx += 288;
+		sx += (SCREEN_WIDTH / 2) - 32;
 		chunks = 6;
 	}
 	if (invflag || sbookflag) {
diff --git a/defs.h b/defs.h
index 3be9e4c16..d1a88fdea 100644
--- a/defs.h
+++ b/defs.h
@@ -121,8 +121,12 @@
 #define PANEL_WIDTH     640
 #define PANEL_HEIGHT    128
 #define PANEL_TOP		(SCREEN_HEIGHT - PANEL_HEIGHT)
-#define PANEL_Y			(PANEL_TOP + SCREEN_Y)
-#define PANEL_RIGHT		(SCREEN_X + SCREEN_WIDTH - 320)
+#define PANEL_LEFT		(SCREEN_WIDTH - PANEL_WIDTH) / 2
+#define PANEL_X			(SCREEN_X + PANEL_LEFT)
+#define PANEL_Y			(SCREEN_Y + PANEL_TOP)
+
+#define RIGHT_PANEL		(SCREEN_WIDTH - 320)
+#define RIGHT_PANEL_X	(SCREEN_X + RIGHT_PANEL)
 
 #if SCREEN_WIDTH == PANEL_WIDTH
 #define VIEWPORT_HEIGHT	(SCREEN_HEIGHT - PANEL_HEIGHT)
@@ -130,6 +134,9 @@
 #define VIEWPORT_HEIGHT	SCREEN_HEIGHT
 #endif
 
+#define DIALOG_TOP		((SCREEN_HEIGHT - PANEL_HEIGHT) / 2 - 18)
+#define DIALOG_Y		(SCREEN_Y + DIALOG_TOP)
+
 #define SCREENXY(x, y)	((x) + SCREEN_X + ((y) + SCREEN_Y) * BUFFER_WIDTH)
 
 #define MemFreeDbg(p)	\