; [Fast Tunnel] for CrASH v1.3 ; by Andrew Von Dollen (Waffy on IRC) ; ; Rewritten partially for speed/space optimizations by Hideaki Omuro (CrASH) ; Ported/modified/redistributed for CrASH with permission. .INCLUDE CRASH82.INC .DB "Fast Tunnel by AVD", 0 x1 = TEXT_MEM ; X coordinate of the left side of the tunnel x2 = TEXT_MEM+1 ; X coordinate of the right side of the tunnel ShipX = TEXT_MEM+2 ; X coordinate of the ship Score = TEXT_MEM+3 ; The score R_ARROW = $01 L_ARROW = $02 DI ; Disable interrupts, just speeds it up a bit LD HL, x1 ; Initialize Variables LD (HL), 24 ; | x1 is 24 [Score is already 0 'cuz INC HL ; | [textmem is cleared in crash LD (HL), 69 ; | x2 is 69 [graph_mem is also cleared INC HL ; | LD (HL), 42 ; \ / ShipX is 42 keyloop: LD HL, (Score) ; Add 1 to the score each turn through the loop INC HL LD (Score), HL CALL Scroll ; Scroll the screen down (2 lines in same routine) LD E, 0 ; Top Row LD A, (x1) LD B, E \ LD C, A CALL BlackLine ; Draw a line from (0, 0) to (x1, 0) LD A, (x2) LD B, A \ LD C, 95 CALL BlackLine ; Draw a line from (x2, 0) to (95, 0) CALL RAND ; Get a 7 bit random number (0-127) (sub inside CrASH) LD HL, x1 CP 63 \ JR C, Add ; If rand<63 then goto 'add' Sub: LD A, (HL) SUB 2 \ JR C, Add ; Can't go off the screen LD (HL), A INC HL DEC (HL) DEC (HL) ; Subtract 2 from both x1 and x2 JR Past_Update ; Jump past the add part Add: INC HL \ LD A, (HL) \ DEC HL ; get x2 CP 94 \ JR NC, Sub ; We don't want to go off the screen INC (HL) INC (HL) INC HL INC (HL) INC (HL) ; Add 2 to both x1 and x2 Past_Update: LD HL, ShipX ; HL contains ShipX offset LD A, %11111110 OUT ($01), A ; Mask out up/down/left/right IN A, ($01) LD B, A BIT 1, B \ JR NZ, NoLeft ; If you get bit 1 set, Left isn't down LD A, (HL) OR A \ JR Z, NoLeft ; Ship can't go off the screen DEC (HL) ; Decrement Ship's X coordinate NoLeft: BIT 2, B \ JR NZ, NoRight ; Right isn't down if bit 2 set LD A, (HL) CP 88 \ JR Z, NoRight ; Can't go off the screen to the right either INC (HL) ; Increment Ship's X coordinate NoRight: LD A, %10111111 ; mask out Mode and Y= OUT ($01), A IN A, ($01) BIT 4, A \ JP Z, EXIT_2_TIOS ; check for Y='s Status BIT 6, A \ JR Z, Exit ; check for Mode's Status ; HL already contains ShipX offset LD C, 63 ; see if the ship has hit anything LD B, (HL) ; goes on for a while... INC B ; [ CALL GetPixel \ JR NZ, Exit ; ] LD A, (HL) \ ADD A, 6 ; [ LD B, A ; ] CALL GetPixel \ JR NZ, Exit ; [ DEC C ; ] LD B, (HL) ; [ INC B \ INC B ; ] CALL GetPixel \ JR NZ, Exit ; [ INC B \ INC B \ INC B ; ] CALL GetPixel \ JR NZ, Exit ; [ DEC C ; ] DEC B \ DEC B ; [ CALL GetPixel \ JR NZ, Exit ; ] INC B ; [ CALL GetPixel \ JR NZ, Exit ;\ / All done checking for a hit CALL PutShip ; Put the ship onto the screen CALL CR_GRBCopy ; Copy GRAPH_MEM to LCD JP keyloop Exit: CALL PutShip ; Put the ship onto the screen CALL CR_GRBCopy ; Copy GRAPH_MEM to LCD LD HL, $0203 ; Set up coords (2, 3) LD ($800C), HL LD HL, ScoreStr ROM_CALL(D_ZT_STR) ; write "Score: " LD HL, (Score) ROM_CALL(D_HL_DECI) ; Display Score (right next to Score:) wait_for_key: CALL CR_KHAND CP L_ARROW \ JR Z, wait_for_key ; If this weren't here, you probably wouldn't see the score screen CP R_ARROW \ JR Z, wait_for_key ; Take them out to see what I mean RET ;컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 ; Scrolls Screen Down by 2 Rows ;컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 Scroll: LD HL, GRAPH_MEM+743 ; start copying 2 rows from the bottom LD DE, GRAPH_MEM+767 ; start copying to the end of GRAPH_MEM LD BC, 744 ; copy 744 bytes LDDR ; load decrement, repeat LD HL, GRAPH_MEM+35 ; start copying 3 rows from the top ; DE points already to 1st row LD BC, 12 ; copy 12 bytes LDDR ; load decrement, repeat LD HL, GRAPH_MEM+10 ; Clear Top Row EX DE, HL LD BC, 11 LD (HL), B LDDR RET PutShip: DrwSpr: ; Another great routine by Movax ** Optimized for TUNNEL (thrashed) LD IX, Ship ; get address to ship sprite, IX -> sprite LD A, (ShipX) ; x coord is ShipX LD HL, GRAPH_MEM+732 ; y coord is always 61, add Graph_mem+61*12 LD D, 0 \ LD E, A ; Do x/8 SRL E \ SRL E \ SRL E ADD HL, DE AND %00000111 ; Get the remainder of x/8 JR Z, Aligned ; Is this sprite aligned to 8*n,y? LD E, 3 ; Line loop LD B, A ; B=how many bits to shift each line LD C, 0 ; C=empty LineLoop: PUSH BC ; Shift loop LD A, (IX+0) ; Get sprite data ShiftLoop: RRA \ RR C DJNZ ShiftLoop OR (HL) \ LD (HL), A ; Write line to graphbuf INC HL LD A, C OR (HL) \ LD (HL), A INC IX LD BC, 11 ; Calculate next line address ADD HL, BC ; Inc spritepointer POP BC DEC E JR NZ, LineLoop ; Next line RET Aligned: ; Blit an aligned sprite to graphbuf LD B, 3 LD DE, 12 AlignedLoop: LD A, (IX+0) OR (HL) ; xor=erase/blit LD (HL), A INC IX ADD HL, DE DJNZ AlignedLoop RET ; ** GetPixel ; Input: Coordinates (B, C) ; Returns: Z is set if pixel is off ; Z is cleared if pixel is on GetPixel: PUSH HL PUSH BC FindPix: ; Same as FIND_PIXEL but maybe faster LD A, B ; Save B (real X val) LD B, 0 LD H, B LD L, C ADD HL, HL ADD HL, BC ADD HL, HL ADD HL, HL LD C, A SRL C SRL C SRL C ADD HL, BC LD BC, GRAPH_MEM ADD HL, BC LD B, %10000000 AND %00000111 JR Z, GetPixDone LD C, A LD A, B LD B, C ShloopGetPix: RRA DJNZ ShloopGetPix LD B, A GetPixDone: LD A, (HL) AND B POP BC POP HL RET ; ** BlackLine from Plain Jump by Andreas Ess ** Modified for TUNNEL ; and optimized (thrashed) ; Returns: Horizontal Line from (B,E)-(C,E) BlackLine: PUSH HL PUSH DE LD HL, GRAPH_MEM ; ** we are always doing top line LD D, 0 \ LD E, B SRL E \ SRL E \ SRL E ; Divide x by 8 ADD HL, DE ; HL now contains video-offset (B, C) LD A, C ; Calc # of times to repeat line loop SUB B INC A \ LD C, A LD A, B ; Load real x1-pos into A AND %00000111 ; and make mask LD B, A ; Find number to shift LD D, %10000000 ; Video-Mask setup LD A, (HL) ; Get Data ready JR Z, BLoop ; Ready for Line Plotting? ShiftBLoop: SRL D DJNZ ShiftBLoop BLoop: ; Ready-go! OR D ; Set bit to black DEC C JR Z, EndBlack ; Decrement Counter - see if done and end RRC D ; Shift mask right JR NC, BLoop ; Did the mask disappear? LD (HL), A \ INC HL \ LD A, (HL) JR BLoop EndBlack: LD (HL), A POP DE POP HL RET Ship .DB %00011000 .DB %00100100 .DB %01011010 ScoreStr .DB "Score: ", 0