03-06-2010, 05:29 AM
I've made quite a few changes to the actual FourSpriter code. I have made it significantly shorter, and not a small amount faster in execution, using tricks like LDI to copy directly from (HL) to (DE) as opposed to copying into and out of the A register. I removed at least one redundant section of code that was identical with another one - redirecting calls took care of that. There are also places that use bafflingly long code to do something simple. For example:
Is used to get the address of the UDG into the HL register. It takes 50 T states to do this, whereas:
Does it in one instruction, and 16 T states.
I know I'm not really that good with Z80 code....but stuff like that leaves me scratching my head.
Anyway, It still seems to catch the ray trace at the top of the screen between erase and draw (which means that for the first frame after updating sprites, you can't see them on the top 24 lines (or 3 characters). It was 26, but I managed to speed it up enough T states to creep back 2 lines
My advice, unless I (or someone else) can work a way around this is to use this area for status bars - or at least avoid running sprites into it.
I tried to make it more user friendly than the original - now all Sprite actions can be controlled fairly easily with calls to routines and functions. Most of these are used internally, and the chances are all a user will need are the routines to initialize, color, move and redraw moved sprites.
Usage:
The actual code. Note that Apenao's example program is already attached at the end.
Code:
ld hl, 23676 ;10
ld a, (hl) ; 7
ld e, a ; 4
ld hl, 23675 ;10
ld a, (hl) ; 7
ld l, a ; 4
ld a, e ; 4
ld h, a ; 4=50
Is used to get the address of the UDG into the HL register. It takes 50 T states to do this, whereas:
Code:
ld HL,(23675)
I know I'm not really that good with Z80 code....but stuff like that leaves me scratching my head.
Anyway, It still seems to catch the ray trace at the top of the screen between erase and draw (which means that for the first frame after updating sprites, you can't see them on the top 24 lines (or 3 characters). It was 26, but I managed to speed it up enough T states to creep back 2 lines

My advice, unless I (or someone else) can work a way around this is to use this area for status bars - or at least avoid running sprites into it.
I tried to make it more user friendly than the original - now all Sprite actions can be controlled fairly easily with calls to routines and functions. Most of these are used internally, and the chances are all a user will need are the routines to initialize, color, move and redraw moved sprites.
Usage:
Code:
fspInit (sprite#, graphicsA,graphicsB,graphicsC,graphicsD,x,y)
Sets sprite sprite # to use the four UDG's listed from 0-20. This also turns on an inactive sprite.
fspDisable(Sprite#)
Shuts down a sprite (internally by setting its first graphic to 99).
fspCoord(sprite#,x,y)
Sets the new co-ordinates for a sprite.
fspAttrs(sprite#, AttrA,AttrB,AttrC,AttrD)
Sets a sprite to have attributes A,B,C,D.
Note: This is the advanced use, that allows different bits of the sprite to be different colours.
fspAttrByte(ink,paper,bright,flash) as uByte
returns an attribute byte equivalent to the input ink,paper,bright and flash.
This function is used by the following subroutine:
fspAttr (sprite#,ink,paper,bright,flash)
Sets ALL four attributes of a sprite to the input values for ink,paper,bright and flash.
This is expected to be the common usage.
Note: Color words are #defined, so you can use fspAttr(0,WHITE,BLACK,FALSE,FALSE) to set a sprite to white on black, no bright, no flash.
fspRedraw()
Back buffer -> screen (erasing sprites)
screen -> back buffer (save background)
sprites -> screen (srawing sprites)
current location -> last location (update location)
In essence it moves the sprites to their new coordinates
It effectively, internally uses the following routines, that the user may not need to call.
They are made available, however, in case the programmer needs more direct control of sprite activity.
fspErase()
Erases all the sprites and replaces them with their background data.
fspBufferBackgroundAndDraw()
Copies screen to buffer and redraws the sprites onto the screen.
fspUpdate()
Updates co-ordinates
The actual code. Note that Apenao's example program is already attached at the end.
Code:
#DEFINE BLACK 0
#DEFINE BLUE 1
#DEFINE RED 2
#DEFINE MAGENTA 3
#DEFINE GREEN 4
#DEFINE CYAN 5
#DEFINE YELLOW 6
#DEFINE WHITE 7
#DEFINE TRANSPARENT 8
#DEFINE CONTRAST 9
#DEFINE TRUE 1
#DEFINE FALSE 0
SUB fspInitialize (n as uByte, udgA as uByte, udgB as uByte, udgC as uByte, udgD as uByte,x as uByte,y as uByte) 'Initialize Sprite: n (sprite number 0-3);a,b,c,d (UDG number 0-20,99 means the sprite won't be printed)
IF n>3 OR (udgA>20 AND udgA<>99) or udgB>20 or udgC>20 or udgD>20 then return : END IF : REM Bounds checking - so a bad function call doesn't poke all over memory.
DIM targetAddr as uInteger
targetAddr=@fspDataStart+(48*n)
fspErase()
POKE targetAddr,udgA
targetAddr=targetAddr+1
POKE targetAddr,udgB
targetAddr=targetAddr+1
POKE targetAddr,udgC
targetAddr=targetAddr+1
POKE targetAddr,udgD
targetAddr=targetAddr+1
POKE targetAddr,x
targetAddr=targetAddr+1
POKE targetAddr,y
targetAddr=targetAddr+1
POKE targetAddr,x
targetAddr=targetAddr+1
POKE targetAddr,y
fspBufferAndDraw()
RETURN
fspDataStart:
REM This Section contains Fourspriter data and code that is called by other routines.
ASM
;; 16x16 Sprites moving a character each frame
;; Copyleft 2009 The Mojon Twins.
;; Pergreñado por na_th_an
;; Uses UDGs (it reads the address from the system variables).
;; It moves up to 4 sprites, preserving the backgrounds.
datap: ; each block is 48 bytes long. [This comment originally said 40 bytes, and it's clearly 48]
;; Sprite 1
udgs1: defb 99,0,0,0 ; Four UDGs of the first sprite.
x_pos1: defb 0 ; X position in chars.
y_pos1: defb 0 ; Y position in chars.
cx_pos1: defb 0 ; Previous X position in chars.
cy_pos1: defb 0 ; Previous Y position in chars.
buffer1: defb 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 ; Background Gfx buffer.
attrs1: defb 7,7,7,7 ; Sprite ATTRs
buffatrs1: defb 0,0,0,0 ; Background Attr's buffer
;; Sprite 2
udgs2: defb 99,0,0,0
x_pos2: defb 0
y_pos2: defb 0
cx_pos2: defb 0
cy_pos2: defb 0
buffer2: defb 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
attrs2: defb 7,7,7,7
buffatrs2: defb 0,0,0,0
;; Sprite 3
udgs3: defb 99,0,0,0
x_pos3: defb 0
y_pos3: defb 0
cx_pos3: defb 0
cy_pos3: defb 0
buffer3: defb 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
attrs3: defb 7,7,7,7
buffatrs3: defb 0,0,0,0
;; Sprite 4
udgs4: defb 99,0,0,0
x_pos4: defb 0
y_pos4: defb 0
cx_pos4: defb 0
cy_pos4: defb 0
buffer4: defb 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
attrs4: defb 7,7,7,7
buffatrs4: defb 0,0,0,0
;; General use coordinates
xpos: defb 0
ypos: defb 0
cxpos: defb 0
cypos: defb 0
;; Sprite control is done writing a certain number
;; in the Sprite's first UDG
;; If the first UDG is 99, it won't be printed
docopy:
borra_char:
call get_scr_address ; Dirección (xpos, ypos) en BC
ld l, c
ld h, b ; Dirección (xpos, ypos) en HL
ld a, (de)
ld (hl), a
inc h
inc de
ld a, (de)
ld (hl), a
inc h
inc de
ld a, (de)
ld (hl), a
inc h
inc de
ld a, (de)
ld (hl), a
inc h
inc de
ld a, (de)
ld (hl), a
inc h
inc de
ld a, (de)
ld (hl), a
inc h
inc de
ld a, (de)
ld (hl), a
inc h
inc de
ld a, (de)
ld (hl), a
inc h
inc de
ret
;; Esta función devuelve en bc la dirección de memoria
;; de la posición (xpos, ypos) en carácteres. Extraído de código
;; por BloodBaz.
get_scr_address:
push de
ld a, (xpos)
and 31
ld c, a
ld a, (ypos)
ld d, a
and 24
add a, 64
ld b, a
ld a, d
and 7
rrca
rrca
rrca
or c
ld c, a
pop de
ret
;; Esta función devuelve en bc la dirección de memoria
;; de la posición (xpos, ypos) dentro del archivo de atributos.
;; Adaptado de código por Jonathan Cauldwell.
;; 010110YY YYYXXXXX
get_attr_address:
ld a, (ypos) ; Cogemos y
rrca
rrca
rrca ; La multiplicamos por 32
ld c, a ; nos lo guardamos en c
and 3 ; ponemos una mascarita 00000011
add a, 88 ; 88 * 256 = 22528, aquí empieza el tema
ld b, a ; Hecho el bite superior.
ld a, c ; Nos volvemos a traer y * 32
and 224 ; Mascarita 11100000
ld c, a ; Lo volvemos a poner en c
ld a, (xpos) ; Cogemos x
add a, c ; Le sumamos lo que teníamos antes.
ld c, a ; Listo. Ya tenemos en BC la dirección.
ret
spare: defb 85,85,85,85,85,85,85,85
;; Routine to save the background to the buffer
;borra_sprites:
; pointer = datap
; for (i = 0; i < 4; i ++) {
; CX = *(pointer + 6)
; CY = *(pointer + 7)
; scr_address = get_scr_address (CX, CY);
; for (j = 0; j < 8; j ++) {
; *scr_address = *(pointer + 8 + j);
; scr_address += 256;
; }
; scr_address = get_scr_address (CX+1, CY);
; for (j = 0; j < 8; j ++) {
; *scr_address = *(pointer + 16 + j);
; scr_address += 256;
; }
; scr_address = get_scr_address (CX, CY+1);
; for (j = 0; j < 8; j ++) {
; *scr_address = *(pointer + 24 + j);
; scr_address += 256;
; }
; scr_address = get_scr_address (CX+1, CY+1);
; for (j = 0; j < 8; j ++) {
; *scr_address = *(pointer + 32 + j);
; scr_address += 256;
; }
; pointer += 40;
; }
fspEraseAsm:
ld de, datap ;
ld b, 4 ;
i4chars2: push bc
;;
ld a, (de)
cp 99
jr z, nxt2
;; A
LD BC,6 ; 10
EX DE,HL ; 4
ADD HL,BC ; 11
; EX DE,HL ; 4
;inc de
;inc de
;inc de
;inc de
;inc de
;inc de
; Obtenemos xpos = CX
ld DE, xpos
;ld a, (de)
;ld (hl), a
LDI
;inc de
; Obtenemos ypos = CY
ld DE, ypos
;ld a, (de)
;ld (hl), a
;inc de
LDI
EX DE,HL
;; B
; Pintamos el primer char
call borra_char
; xpos++
ld hl, xpos
inc (hl)
;; C
; Pintamos el segundo char
call borra_char
; xpos --
ld hl, xpos
;ld a, (hl)
;dec a
;ld (hl), a
dec (hl)
; ypos ++
ld hl, ypos
inc (hl)
;; D
; Pintamos el tercer char
call borra_char
; xpos++
ld hl, xpos
inc (hl)
;; E
; Pintamos el cuarto char
call borra_char
;; attr
inc de
inc de
inc de
inc de
;;
; xpos --
ld hl, xpos
dec (hl)
; ypos --
ld hl, ypos
dec (hl)
;
call get_attr_address
;
call copyattrs
;
nxt2: pop bc
djnz i4chars2
ret
copia_char:
call get_scr_address ;
ld l, c
ld h, b ;
ld a, (hl)
ld (de), a
inc h
inc de
ld a, (hl)
ld (de), a
inc h
inc de
ld a, (hl)
ld (de), a
inc h
inc de
ld a, (hl)
ld (de), a
inc h
inc de
ld a, (hl)
ld (de), a
inc h
inc de
ld a, (hl)
ld (de), a
inc h
inc de
ld a, (hl)
ld (de), a
inc h
inc de
ld a, (hl)
ld (de), a
inc h
inc de
ret
fspBufferAndDrawAsm:
init_sprites:
; pointer = datap
; for (i = 0; i < 4; i ++) {
; X = *(pointer + 4); // A
; Y = *(pointer + 5);
; scr_address = get_scr_address (X, Y); // B
; for (j = 0; j < 8; j ++) {
; *(pointer + 8 + j) = *scraddress;
; scraddress += 256;
; }
; scr_address = get_scr_address (X+1, Y); // C
; for (j = 0; j < 8; j ++) {
; *(pointer + 16 + j) = *scraddress;
; scraddress += 256;
; }
; scr_address = get_scr_address (X, Y+1); // D
; for (j = 0; j < 8; j ++) {
; *(pointer + 24 + j) = *scraddress;
; scraddress += 256;
; }
; scr_address = get_scr_address (X+1, Y+1); // E
; for (j = 0; j < 8; j ++) {
; *(pointer + 32 + j) = *scraddress;
; scraddress += 256;
; }
; pointer = pointer + 40;
; }
ld de, datap ;
ld b, 4 ;
i4chars: push bc
;;
ld a, (de)
cp 99
jr z, nxt1
;; A
EX DE,HL
LD BC,4
ADD HL,BC
;inc de
;inc de
;inc de
;inc de
;
ld DE, xpos
;ld a, (de)
;ld (hl), a
;inc de
LDI
;
ld DE, ypos
;ld a, (de)
;ld (hl), a
;inc de
LDI
EX DE,HL
inc de
inc de
;; B
;
call copia_char
; xpos++
ld hl, xpos
inc (hl)
;; C
;
call copia_char
; xpos --
ld hl, xpos
dec (hl)
; ypos ++
ld hl, ypos
inc (hl)
;; D
;
call copia_char
; xpos++
ld hl, xpos
inc (hl)
;; E
;
call copia_char
;; Now we point to the ATTR buffer,adding 4:
inc de
inc de
inc de
inc de
;;
; xpos --
ld hl, xpos
dec (hl)
; ypos --
ld hl, ypos
dec (hl)
;
call get_attr_address
;
ld l, c
ld h, b
ld bc, 32
;ld a, (hl)
;ld (de), a ; Primer carácter
;inc hl
;inc de
LDI ; bc was loaded with 32 instead of 31 to account for the BC-- this instruction has.
;ld a, (hl)
;ld (de), a ; Segundo carácter
;inc de
LDI
add hl, bc ; we can get away with this because BC++ as well as hl--
;ld a, (hl)
;ld (de), a ; Tercer carácter
;inc hl
;inc de
LDI
;ld a, (hl)
;ld (de), a ; Cuarto carácter
;inc de
LDI
; Fin del bucle
nxt1: pop bc
djnz i4chars
; ret - No! Go straight into Painting new sprites for speed.
;; Print sprites routine
;; UDGs are labeled from 0 to 21. The addres of the UDG is:
;; *(23675) + 256 * *(23676) + 8 * N
fspDrawAsm:
draw_sprites:
ld de, datap ;
ld b, 4 ;
i4chars3: push bc
ld a, (de)
cp 99
jr z, nxt3
;; copiar aquí "de" a un buffer
call charsabuff
; Obtenemos xpos
ld hl, xpos
EX DE,HL
;ld a, (de)
;ld (hl), a
;inc de
LDI
; Obtenemos ypos
;ld a, (de)
ld DE, ypos
;ld (hl), a
;inc de
LDI
inc HL ; de
inc HL ; de
push HL ; de
ld hl, bufchars
call getde
call docopy
; xpos++
ld hl, xpos
inc (hl)
; Dirección del gráfico
ld hl, bufchars+1
;inc hl
call getde
; Pintamos el segundo char
call docopy
; xpos--
ld hl, xpos
ld a, (hl)
dec a
ld (hl), a
; ypos ++
ld hl, ypos
inc (hl)
; Dirección del gráfico
ld hl, bufchars+2
;inc hl
;inc hl
call getde
; Pintamos el tercer char
call docopy
; xpos ++
ld hl, xpos
inc (hl)
; Dirección del gráfico
ld hl, bufchars+3
;inc hl
;inc hl
;inc hl
call getde
; Pintamos el cuarto char
call docopy
pop de
; de = de + 32
ld bc, 32
ld h, d
ld l, e
add hl, bc
ld d, h
ld e, l
;; attr
; xpos --
ld hl, xpos
;ld a, (hl)
;dec a
;ld (hl), a
dec (hl)
; ypos --
ld hl, ypos
;ld a, (hl)
;dec a
;ld (hl), a
dec(hl)
;
call get_attr_address
;
call copyattrs
inc de
inc de
inc de
inc de ;
nxt3: pop bc
djnz i4chars3
ret
;; Esta función calcula la posición en memoria del UDG apuntado por
;; el número que está en la dirección hl.
getde: ld a, (hl)
;ld d, a
;ld hl, 23676
;ld a, (hl)
;ld e, a
;ld hl, 23675
;ld a, (hl)
;ld l, a
;ld a, e
;ld h, a
ld HL,(23675)
;; HL = *(23675) + 256 * *(23676)
;ld a, d
rlca
rlca
rlca ; a = N * 8
ld d, 0
ld e, a
add hl, de
;ld d, h
;ld e, l
EX DE,HL
ret
bufchars: defb 0,0,0, 0 ;
charsabuff: ld hl, bufchars
EX DE,HL
LDI
LDI
LDI
LDI
EX DE,HL
ret
copyattrs: ld l, c
ld h, b
ld bc, 31
ld a, (de)
ld (hl), a ; Primer carácter
inc hl
inc de
ld a, (de)
ld (hl), a ; Segundo carácter
add hl, bc
inc de
ld a, (de)
ld (hl), a ; Tercer carácter
inc hl
inc de
ld a, (de)
ld (hl), a ; Cuarto carácter
inc de ; Ahora de apunta a datap+48, o sea, al siguiente sprite.
ret
fspUpdateAsm:
update_coordinates:
ld de, datap ; Apuntamos a la zona de datos
ld hl, datap ; idem
ld b, 4 ; 4 iteraciones
i4chars4: push bc
;; Para cada sprite hay que hacer:
;; *(datap + 6) = *(datap + 4)
;; *(datap + 7) = *(datap + 5)
inc de
inc de
inc de
inc de
ld a, (de) ; a = X
inc hl
inc hl
inc hl
inc hl
inc hl
inc hl
ld (hl), a ; CX = a
inc de
ld a, (de) ; a = Y
inc hl
ld (hl), a ; CY = a
inc hl
;; hl = hl + 40
ld bc, 40
add hl, bc
;; de = hl
ld d, h
ld e, l
pop bc
djnz i4chars4
ret
END ASM
END SUB
SUB fspDisable (n as UByte)
IF n>3 then return : END IF
POKE @fspDataStart+48*n,99
end SUB
SUB fspCoord (n as uByte, x as uByte, y as uByte) 'Set sprite coords: n (sprite number);x,y (vertical,horizontal coords)
IF n>3 then return : END IF
DIM targetAddr as uInteger
targetAddr=@fspDataStart+4+48*n
POKE targetAddr,x
targetAddr=targetAddr+1
POKE targetAddr,y
rem targetAddr=targetAddr+1
rem POKE targetAddr,x
rem targetAddr=targetAddr+1
rem POKE targetAddr,y
END SUB
SUB fspAttrs (n as uByte, attra as uByte, attrb as uByte, attrc as uByte, attrd as uByte) 'Set sprite attrs: n (sprite number);a,b,c,d (UDG attrs)
IF n>3 then return : END IF
DIM targetAddr as uInteger
targetAddr=@fspDataStart+40+48*n
POKE targetAddr,attra
targetAddr=targetAddr+1
POKE targetAddr,attrb
targetAddr=targetAddr+1
POKE targetAddr,attrc
targetAddr=targetAddr+1
POKE targetAddr,attrd
END SUB
FUNCTION fspAttrByte(fspInk as uByte,fspPaper as uByte,fspBright as uByte, fspFlash as uByte) as uByte
if fspInk > 7 OR fspPaper > 7 OR fspBright > 1 or fspFlash >1 then return 0: END IF: Rem bounds check
return (fspFlash shl 7) + (fspBright shl 6) + (fspPaper shl 3) + fspInk
END FUNCTION
SUB fspAttr(n as uByte,fspInk as uByte,fspPaper as uByte,fspBright as uByte, fspFlash as uByte)
if fspInk > 7 OR fspPaper > 7 OR fspBright > 1 or fspFlash >1 then return : END IF: Rem bounds check
DIM attrByte as uByte
attrByte=fspAttrByte(fspInk,fspPaper,fspBright,fspFlash)
fspAttrs(n,attrByte,attrByte,attrByte,attrByte)
END SUB
SUB FASTCALL fspErase()
asm
call fspEraseAsm
end asm
END SUB
SUB FASTCALL fspBufferAndDraw()
asm
call fspBufferAndDrawAsm
end asm
END SUB
SUB FASTCALL fspUpdate()
asm
call fspUpdateAsm
END ASM
END SUB
SUB fspRedraw()
asm
halt
;REM Erase the sprites
call fspEraseAsm
;REM Save background and
;REM print sprites
call fspBufferAndDrawAsm
;REM update coordinates
call fspUpdateAsm
end asm
END SUB
REM below this is Apenao's Demo Program:
#include <sinclair.bas>
#include <memcopy.bas>
#include <keys.bas>
100 DIM gentle (0 to 3,0 to 7) AS uByte => { { 15, 15, 15, 15, 15, 15, 13, 15} , _
{ 240, 144, 208, 208, 240, 240, 176, 240} , _
{ 15, 14, 63, 0, 0, 12, 26, 30} , _
{ 176, 112, 252, 0, 0, 48, 104, 120}}
110 POKE Uinteger 23675, @gentle(0,0)
memcopy (0,16384,4092)
LET gx=10:LET gy=10:let dx=3:let dy=3:let tx=6:let ty=6:let cx=18:let cy=18
let dmx=1:let dmy=1:let tmx=-1:let tmy=-1:let cmx=1:let cmy=-1
fspInitialize (0,0,1,2,3,gx,gy) : REM (sprite number, udgA, udgB,udgC,udgD, initial X co-ordinate, initial y-coordinate)
fspInitialize (1,0,1,2,3,dx,dy)
fspInitialize (2,0,1,2,3,tx,ty)
fspInitialize (3,0,1,2,3,cx,cy)
fspAttr(0,WHITE,MAGENTA,FALSE,FALSE) : REM (sprite number, ink, paper, bright, flash)
fspAttr(1,YELLOW,BLACK,FALSE,FALSE)
fspAttr(2,GREEN,BLUE,TRUE,FALSE)
fspAttr(3,RED,WHITE,FALSE,FALSE)
DO
pause 2
IF MULTIKEYS(KEYO)<>0 and gx>0 THEN LET gx=gx-1: END IF
IF MULTIKEYS(KEYP)<>0 and gx<30 THEN LET gx=gx+1:END IF
IF MULTIKEYS(KEYQ)<>0 and gy>0 THEN LET gy=gy-1 :END IF
IF MULTIKEYS(KEYA)<>0 and gy<22 THEN LET gy=gy+1: END IF
let dx=dx+dmx:if dx=0 or dx=30 then let dmx=-dmx : END IF
let dy=dy+dmy:if dy=0 or dy=22 then let dmy=-dmy: END IF
let tx=tx+tmx:if tx=0 or tx=30 then let tmx=-tmx: END IF
let ty=ty+tmy:if ty=0 or ty=22 then let tmy=-tmy: END IF
let cx=cx+cmx:if cx=0 or cx=30 then let cmx=-cmx: END IF
let cy=cy+cmy:if cy=0 or cy=22 then let cmy=-cmy: END IF
fspCoord (0,gx,gy)
fspCoord (1,dx,dy)
fspCoord (2,tx,ty)
fspCoord (3,cx,cy)
fspRedraw()
loop