add border constant and clear up misnomer

constants/connection_constants.asm

@@ -1,3 +1,7 @@
+; width of east/west connections
+; height of north/south connections
+MAP_BORDER EQU 3
+
 ; connection directions
 EAST  EQU 1
 WEST  EQU 2

constants/misc_constants.asm

@@ -25,13 +25,14 @@ D_LEFT   EQU %00100000
 D_UP     EQU %01000000
 D_DOWN   EQU %10000000
 
-PIXELS_PER_TILE EQU 8
-
 SCREEN_WIDTH  EQU 20
 SCREEN_HEIGHT EQU 18
 
-SCREEN_WIDTH_PIXELS  EQU SCREEN_WIDTH * PIXELS_PER_TILE
+SCREEN_WIDTH_PIXELS  EQU SCREEN_WIDTH * 8
-SCREEN_HEIGHT_PIXELS EQU SCREEN_HEIGHT * PIXELS_PER_TILE
+SCREEN_HEIGHT_PIXELS EQU SCREEN_HEIGHT * 8
+
+BG_MAP_WIDTH  EQU 32
+BG_MAP_HEIGHT EQU 32
 
 NPC_MOVEMENT_DOWN  EQU $00
 NPC_MOVEMENT_UP    EQU $40

engine/trade.asm

@@ -552,14 +552,14 @@ Trade_CopyCableTilesOffScreen: ; 414ae (10:54ae)
 ; continues when the screen is scrolled.
 	push hl
 	coord hl, 0, 4
-	call CopyToScreenEdgeTiles
+	call CopyToRedrawRowOrColumnSrcTiles
 	pop hl
 	ld a, h
-	ld [H_SCREENEDGEREDRAWADDR + 1], a
+	ld [hRedrawRowOrColumnDest + 1], a
 	ld a, l
-	ld [H_SCREENEDGEREDRAWADDR], a
+	ld [hRedrawRowOrColumnDest], a
-	ld a, REDRAWROW
+	ld a, REDRAW_ROW
-	ld [H_SCREENEDGEREDRAW], a
+	ld [hRedrawRowOrColumnMode], a
 	ld c, 10
 	jp DelayFrames
 

home/overworld.asm

@@ -555,10 +555,10 @@ CheckMapConnections:: ; 07ba (0:07ba)
 	jr z,.savePointer1
 .pointerAdjustmentLoop1
 	ld a,[wWestConnectedMapWidth] ; width of connected map
-	add a,$06
+	add a,MAP_BORDER * 2
 	ld e,a
-	ld d,$00
+	ld d,0
-	ld b,$00
+	ld b,0
 	add hl,de
 	dec c
 	jr nz,.pointerAdjustmentLoop1
@@ -591,10 +591,10 @@ CheckMapConnections:: ; 07ba (0:07ba)
 	jr z,.savePointer2
 .pointerAdjustmentLoop2
 	ld a,[wEastConnectedMapWidth]
-	add a,$06
+	add a,MAP_BORDER * 2
 	ld e,a
-	ld d,$00
+	ld d,0
-	ld b,$00
+	ld b,0
 	add hl,de
 	dec c
 	jr nz,.pointerAdjustmentLoop2
@@ -883,15 +883,15 @@ LoadTileBlockMap:: ; 09fc (0:09fc)
 	ld hl,wOverworldMap
 	ld a,[W_CURMAPWIDTH]
 	ld [hMapWidth],a
-	add a,$06 ; border (east and west)
+	add a,MAP_BORDER * 2 ; east and west
 	ld [hMapStride],a ; map width + border
-	ld b,$00
+	ld b,0
 	ld c,a
 ; make space for north border (next 3 lines)
 	add hl,bc
 	add hl,bc
 	add hl,bc
-	ld c,$03
+	ld c,MAP_BORDER
 	add hl,bc ; this puts us past the (west) border
 	ld a,[W_MAPDATAPTR] ; tile map pointer
 	ld e,a
@@ -995,7 +995,7 @@ LoadTileBlockMap:: ; 09fc (0:09fc)
 	ret
 
 LoadNorthSouthConnectionsTileMap:: ; 0ade (0:0ade)
-	ld c,$03
+	ld c,MAP_BORDER
 .loop
 	push de
 	push hl
@@ -1016,7 +1016,7 @@ LoadNorthSouthConnectionsTileMap:: ; 0ade (0:0ade)
 	inc h
 .noCarry1
 	ld a,[W_CURMAPWIDTH]
-	add a,$06
+	add a,MAP_BORDER * 2
 	add e
 	ld e,a
 	jr nc,.noCarry2
@@ -1029,7 +1029,7 @@ LoadNorthSouthConnectionsTileMap:: ; 0ade (0:0ade)
 LoadEastWestConnectionsTileMap:: ; 0b02 (0:0b02)
 	push hl
 	push de
-	ld c,$03
+	ld c,MAP_BORDER
 .innerLoop
 	ld a,[hli]
 	ld [de],a
@@ -1045,7 +1045,7 @@ LoadEastWestConnectionsTileMap:: ; 0b02 (0:0b02)
 	inc h
 .noCarry1
 	ld a,[W_CURMAPWIDTH]
-	add a,$06
+	add a,MAP_BORDER * 2
 	add e
 	ld e,a
 	jr nc,.noCarry2
@@ -1387,7 +1387,7 @@ LoadCurrentMapView:: ; 0caa (0:0caa)
 ; update tile block map pointer to next row's address
 	pop de
 	ld a,[W_CURMAPWIDTH]
-	add a,$06
+	add a,MAP_BORDER * 2
 	add e
 	ld e,a
 	jr nc,.noCarry
@@ -1418,7 +1418,7 @@ LoadCurrentMapView:: ; 0caa (0:0caa)
 	ld bc,$0002
 	add hl,bc
 .copyToVisibleAreaBuffer
-	coord de, 0, 0 ; base address for the tiles that are directly transfered to VRAM during V-blank
+	coord de, 0, 0 ; base address for the tiles that are directly transferred to VRAM during V-blank
 	ld b, SCREEN_HEIGHT
 .rowLoop2
 	ld c, SCREEN_WIDTH
@@ -1662,7 +1662,7 @@ MoveTileBlockMapPointerWest:: ; 0e6f (0:0e6f)
 	ret
 
 MoveTileBlockMapPointerSouth:: ; 0e79 (0:0e79)
-	add a,$06
+	add a,MAP_BORDER * 2
 	ld b,a
 	ld a,[de]
 	add b
@@ -1675,7 +1675,7 @@ MoveTileBlockMapPointerSouth:: ; 0e79 (0:0e79)
 	ret
 
 MoveTileBlockMapPointerNorth:: ; 0e85 (0:0e85)
-	add a,$06
+	add a,MAP_BORDER * 2
 	ld b,a
 	ld a,[de]
 	sub b
@@ -1692,17 +1692,17 @@ MoveTileBlockMapPointerNorth:: ; 0e85 (0:0e85)
 
 ScheduleNorthRowRedraw:: ; 0e91 (0:0e91)
 	coord hl, 0, 0
-	call CopyToScreenEdgeTiles
+	call CopyToRedrawRowOrColumnSrcTiles
 	ld a,[wMapViewVRAMPointer]
-	ld [H_SCREENEDGEREDRAWADDR],a
+	ld [hRedrawRowOrColumnDest],a
 	ld a,[wMapViewVRAMPointer + 1]
-	ld [H_SCREENEDGEREDRAWADDR + 1],a
+	ld [hRedrawRowOrColumnDest + 1],a
-	ld a,REDRAWROW
+	ld a,REDRAW_ROW
-	ld [H_SCREENEDGEREDRAW],a
+	ld [hRedrawRowOrColumnMode],a
 	ret
 
-CopyToScreenEdgeTiles:: ; 0ea6 (0:0ea6)
+CopyToRedrawRowOrColumnSrcTiles:: ; 0ea6 (0:0ea6)
-	ld de,wScreenEdgeTiles
+	ld de,wRedrawRowOrColumnSrcTiles
 	ld c,2 * SCREEN_WIDTH
 .loop
 	ld a,[hli]
@@ -1714,7 +1714,7 @@ CopyToScreenEdgeTiles:: ; 0ea6 (0:0ea6)
 
 ScheduleSouthRowRedraw:: ; 0eb2 (0:0eb2)
 	coord hl, 0, 16
-	call CopyToScreenEdgeTiles
+	call CopyToRedrawRowOrColumnSrcTiles
 	ld a,[wMapViewVRAMPointer]
 	ld l,a
 	ld a,[wMapViewVRAMPointer + 1]
@@ -1724,11 +1724,11 @@ ScheduleSouthRowRedraw:: ; 0eb2 (0:0eb2)
 	ld a,h
 	and a,$03
 	or a,$98
-	ld [H_SCREENEDGEREDRAWADDR + 1],a
+	ld [hRedrawRowOrColumnDest + 1],a
 	ld a,l
-	ld [H_SCREENEDGEREDRAWADDR],a
+	ld [hRedrawRowOrColumnDest],a
-	ld a,REDRAWROW
+	ld a,REDRAW_ROW
-	ld [H_SCREENEDGEREDRAW],a
+	ld [hRedrawRowOrColumnMode],a
 	ret
 
 ScheduleEastColumnRedraw:: ; 0ed3 (0:0ed3)
@@ -1742,15 +1742,15 @@ ScheduleEastColumnRedraw:: ; 0ed3 (0:0ed3)
 	add a,18
 	and a,$1f
 	or b
-	ld [H_SCREENEDGEREDRAWADDR],a
+	ld [hRedrawRowOrColumnDest],a
 	ld a,[wMapViewVRAMPointer + 1]
-	ld [H_SCREENEDGEREDRAWADDR + 1],a
+	ld [hRedrawRowOrColumnDest + 1],a
-	ld a,REDRAWCOL
+	ld a,REDRAW_COL
-	ld [H_SCREENEDGEREDRAW],a
+	ld [hRedrawRowOrColumnMode],a
 	ret
 
 ScheduleColumnRedrawHelper:: ; 0ef2 (0:0ef2)
-	ld de,wScreenEdgeTiles
+	ld de,wRedrawRowOrColumnSrcTiles
 	ld c,SCREEN_HEIGHT
 .loop
 	ld a,[hli]
@@ -1773,11 +1773,11 @@ ScheduleWestColumnRedraw:: ; 0f08 (0:0f08)
 	coord hl, 0, 0
 	call ScheduleColumnRedrawHelper
 	ld a,[wMapViewVRAMPointer]
-	ld [H_SCREENEDGEREDRAWADDR],a
+	ld [hRedrawRowOrColumnDest],a
 	ld a,[wMapViewVRAMPointer + 1]
-	ld [H_SCREENEDGEREDRAWADDR + 1],a
+	ld [hRedrawRowOrColumnDest + 1],a
-	ld a,REDRAWCOL
+	ld a,REDRAW_COL
-	ld [H_SCREENEDGEREDRAW],a
+	ld [hRedrawRowOrColumnMode],a
 	ret
 
 ; function to write the tiles that make up a tile block to memory

home/vblank.asm

@@ -22,7 +22,7 @@ VBlank::
 
 	call AutoBgMapTransfer
 	call VBlankCopyBgMap
-	call RedrawExposedScreenEdge
+	call RedrawRowOrColumn
 	call VBlankCopy
 	call VBlankCopyDouble
 	call UpdateMovingBgTiles

home/vcopy.asm

@@ -33,23 +33,26 @@ ClearBgMap:: ; 1cf0 (0:1cf0)
 	jr nz,.loop
 	ret
 
-; When the player takes a step, a row or column of 2x2 tile blocks at the edge
+RedrawRowOrColumn:: ; 1d01 (0:1d01)
-; of the screen toward which they moved is exposed and has to be redrawn.
+; This function redraws a BG row of height 2 or a BG column of width 2.
-; This function does the redrawing.
+; One of its main uses is redrawing the row or column that will be exposed upon
-RedrawExposedScreenEdge:: ; 1d01 (0:1d01)
+; scrolling the BG when the player takes a step. Redrawing only the exposed
-	ld a,[H_SCREENEDGEREDRAW]
+; row or column is more efficient than redrawing the entire screen.
+; However, this function is also called repeatedly to redraw the whole screen
+; when necessary. It is also used in trade animation and elevator code.
+	ld a,[hRedrawRowOrColumnMode]
 	and a
 	ret z
 	ld b,a
 	xor a
-	ld [H_SCREENEDGEREDRAW],a
+	ld [hRedrawRowOrColumnMode],a
 	dec b
 	jr nz,.redrawRow
 .redrawColumn
-	ld hl,wScreenEdgeTiles
+	ld hl,wRedrawRowOrColumnSrcTiles
-	ld a,[H_SCREENEDGEREDRAWADDR]
+	ld a,[hRedrawRowOrColumnDest]
 	ld e,a
-	ld a,[H_SCREENEDGEREDRAWADDR + 1]
+	ld a,[hRedrawRowOrColumnDest + 1]
 	ld d,a
 	ld c,SCREEN_HEIGHT
 .loop1
@@ -58,7 +61,7 @@ RedrawExposedScreenEdge:: ; 1d01 (0:1d01)
 	inc de
 	ld a,[hli]
 	ld [de],a
-	ld a,31
+	ld a,BG_MAP_WIDTH - 1
 	add e
 	ld e,a
 	jr nc,.noCarry
@@ -72,23 +75,24 @@ RedrawExposedScreenEdge:: ; 1d01 (0:1d01)
 	dec c
 	jr nz,.loop1
 	xor a
-	ld [H_SCREENEDGEREDRAW],a
+	ld [hRedrawRowOrColumnMode],a
 	ret
 .redrawRow
-	ld hl,wScreenEdgeTiles
+	ld hl,wRedrawRowOrColumnSrcTiles
-	ld a,[H_SCREENEDGEREDRAWADDR]
+	ld a,[hRedrawRowOrColumnDest]
 	ld e,a
-	ld a,[H_SCREENEDGEREDRAWADDR + 1]
+	ld a,[hRedrawRowOrColumnDest + 1]
 	ld d,a
 	push de
-	call .drawHalf ; draw upper half
+	call .DrawHalf ; draw upper half
 	pop de
-	ld a,32 ; width of VRAM background map
+	ld a,BG_MAP_WIDTH ; width of VRAM background map
 	add e
 	ld e,a
-			 ; draw lower half
+	; fall through and draw lower half
-.drawHalf
+
-	ld c,10
+.DrawHalf
+	ld c,SCREEN_WIDTH / 2
 .loop2
 	ld a,[hli]
 	ld [de],a
@@ -113,7 +117,7 @@ RedrawExposedScreenEdge:: ; 1d01 (0:1d01)
 ; background per V-blank. It cycles through which third it draws.
 ; This transfer is turned off when walking around the map, but is turned
 ; on when talking to sprites, battling, using menus, etc. This is because
-; the above function, RedrawExposedScreenEdge, is used when walking to
+; the above function, RedrawRowOrColumn, is used when walking to
 ; improve efficiency.
 AutoBgMapTransfer:: ; 1d57 (0:1d57)
 	ld a,[H_AUTOBGTRANSFERENABLED]
@@ -302,12 +306,11 @@ VBlankCopyDouble::
 
 
 VBlankCopy::
-; Copy [H_VBCOPYSIZE] 2bpp tiles
+; Copy [H_VBCOPYSIZE] 2bpp tiles (or 16 * [H_VBCOPYSIZE] tile map entries)
 ; from H_VBCOPYSRC to H_VBCOPYDEST.
 
-; Source and destination addresses
+; Source and destination addresses are updated,
-; are updated, so transfer can
+; so transfer can continue in subsequent calls.
-; continue in subsequent calls.
 
 	ld a, [H_VBCOPYSIZE]
 	and a

hram.asm

@@ -242,12 +242,12 @@ H_VBCOPYDOUBLEDEST EQU $FFCE
 ; 00 = no redraw
 ; 01 = redraw column
 ; 02 = redraw row
-H_SCREENEDGEREDRAW EQU $FFD0
+hRedrawRowOrColumnMode EQU $FFD0
 
-REDRAWCOL EQU 1
+REDRAW_COL EQU 1
-REDRAWROW EQU 2
+REDRAW_ROW EQU 2
 
-H_SCREENEDGEREDRAWADDR EQU $FFD1
+hRedrawRowOrColumnDest EQU $FFD1
 
 hRandomAdd EQU $FFD3
 hRandomSub EQU $FFD4

macros.asm

@@ -104,6 +104,14 @@ dwCoord: MACRO
 	dw wTileMap + 20 * \2 + \1
 	ENDM
 
+;\1 = r
+;\2 = X
+;\3 = Y
+;\4 = map width
+overworldMapCoord: MACRO
+	ld \1, wOverworldMap + ((\2) + 3) + (((\3) + 3) * ((\4) + (3 * 2)))
+	ENDM
+
 ;\1 = Map Width
 ;\2 = Rows above (Y-blocks)
 ;\3 = X movement (X-blocks)

main.asm

@@ -3184,7 +3184,7 @@ RedrawMapView: ; eedc (3:6edc)
 	add hl, de
 	dec a
 	jr nz, .calcWRAMAddrLoop
-	call CopyToScreenEdgeTiles
+	call CopyToRedrawRowOrColumnSrcTiles
 	pop hl
 	ld de, $20
 	ld a, [$ffbe]
@@ -3196,11 +3196,11 @@ RedrawMapView: ; eedc (3:6edc)
 	or $98
 	dec c
 	jr nz, .calcVRAMAddrLoop
-	ld [H_SCREENEDGEREDRAWADDR + 1], a
+	ld [hRedrawRowOrColumnDest + 1], a
 	ld a, l
-	ld [H_SCREENEDGEREDRAWADDR], a
+	ld [hRedrawRowOrColumnDest], a
-	ld a, REDRAWROW
+	ld a, REDRAW_ROW
-	ld [H_SCREENEDGEREDRAW], a
+	ld [hRedrawRowOrColumnMode], a
 	call DelayFrame
 	ld hl, $ffbe
 	inc [hl]

scripts/vermiliondock.asm

@@ -181,12 +181,12 @@ VermilionDock_1dc7c: ; 1dc7c (7:5c7c)
 VermilionDock_EraseSSAnne: ; 1dc94 (7:5c94)
 ; Fill the area the S.S. Anne occupies in BG map 0 with water tiles.
 	ld hl, wVermilionDockTileMapBuffer
-	ld bc, (5 * 32) + SCREEN_WIDTH
+	ld bc, (5 * BG_MAP_WIDTH) + SCREEN_WIDTH
 	ld a, $14 ; water tile
 	call FillMemory
-	ld hl, vBGMap0 + 10 * 32
+	ld hl, vBGMap0 + 10 * BG_MAP_WIDTH
 	ld de, wVermilionDockTileMapBuffer
-	ld bc, (6 * 32) / 16
+	ld bc, (6 * BG_MAP_WIDTH) / 16
 	call CopyVideoData
 
 ; Replace the blocks of the lower half of the ship with water blocks. This
@@ -194,7 +194,7 @@ VermilionDock_EraseSSAnne: ; 1dc94 (7:5c94)
 ; the blocks is unnecessary because the blocks the ship occupies are south of
 ; the player and won't be redrawn when the player automatically walks north and
 ; exits the map. This code could be removed without affecting anything.
-	ld hl, wOverworldMap + (5 + 3) + (2 + 3) * (VERMILION_DOCK_WIDTH + 6) ; (5, 2)
+	overworldMapCoord hl, 5, 2, VERMILION_DOCK_WIDTH
 	ld a, $d ; water block
 	ld [hli], a
 	ld [hli], a

wram.asm

@@ -287,8 +287,8 @@ wTempPic::
 wOverworldMap:: ; c6e8
 	ds 1300
 
-wScreenEdgeTiles:: ; cbfc
+wRedrawRowOrColumnSrcTiles:: ; cbfc
-; the tiles of the row or column to be redrawn by RedrawExposedScreenEdge
+; the tiles of the row or column to be redrawn by RedrawRowOrColumn
 	ds 20 * 2
 
 ; coordinates of the position of the cursor for the top menu item (id 0)