Forum - Program "Flame" and "Dragon."

(C) Telitsin S., Nizhnekamsk


   I am a passionate lover of the spectrum and
ZX REVIEW I read the first issue,
but it did not bother to write - somehow not up to it.
Go directly to the case.

   Suggest to your competition studies a small program. It is 
written, though not by me, but I bring it to the author's 
permission Mihal Soft °. This so-called

"Flame".


            org 5CD0h

begin: ld bc, 3E8h
loop_1: dec bc

            ld a, b

            or c

            jr nz, loop_1

            ld de, 5B00h

            ld b, 20h
loop_2: inc hl

            ld a, h

            and 1Fh

            ld h, a

            ld a, (hl)

            rra

            ld a, 0

            jr c, loop_3

            ld a, 3Fh
loop_3: ld (de), a

            inc de

            djnz loop_2

            ld ix, 57FFh

            ld bc, 300h
loop_4: ld a, (ix +32)

            add a, (ix +33)

            add a, (ix +34)

            add a, (ix +65)

            srl a

            srl a

            jr z, loop_5

            dec a
loop_5: inc ix

            ld (ix +0), a

            dec bc

            ld a, b

            or c

            jr nz, loop_4

            ld a, 7Fh

            in a, (0FEh)

            rra

            jr c, begin

            ret


    Fucking nice, is not it
right? In addition, if you use a second screen on the 
128K-machine, you can do this: on one screen familiarity 2 
colors on the other two, and in the course of the beam

switch every 4 rows. Thus, the resolution
increase in 2 times.


    Ca. Ed.: The above effect, as
easy to see, depends on the content
Memories # 5B20-# 5B3F, which is not defined in the program. 
Therefore, before starting the effect is better to set the 
values these cells (eg, equal to 0 or # FF),

that the effect did not depend on random numbers that could be 
there. 


    Besides, I want to offer
interesting, in my opinion, the subject
for discussion (fractals and graftaly - what it is), and
example, offer a small example of my own: "Dragon": 140.

X_Y EQU # 4040

        ORG 40000

        DI

        LD BC, X_Y

        CALL PRINT

        LD D, 0

        LD E, 1
BEGIN LD A, E
DEL_2 SRL A

        JR C, NECET

        JR DEL_2
NECET RLA

        LD H, A

        SRL H

        SRL H

        SLA H

        SLA H

        SUB H

        LD H, A

        CP 1

        JR NZ, NE_1

        LD A, D

        AND A

        JR Z, D_03

        DEC D

        JR DALEE
NE_1 INC D

        JR DALEE
D_03 LD D, 3
DALEE LD A, D

        CP 4

        JR NZ, DALE2

        LD D, 0
DALE2 LD A, D

        AND A

        JR Z, _0_2

        LD A, D

        CP 1

        JR Z, _2_0

        LD A, D

        CP 2

        JR Z, _0__2

        LD A, D

        CP 3

        JR Z, __2_0
PP1 INC E

        JR NC, BEGIN

        EI

        RET
_0_2 INC C

        CALL PRINT

        JR PP1
_2_0 INC B

        CALL PRINT

        JR PP1
_0__2 DEC C

        CALL PRINT

        JR PP1
__2_0 DEC B

        CALL PRINT

        JR PP1
PRINT PUSH BC

        PUSH DE

        CALL 8933

        POP DE

        POP BC

        RET
2

   Here is given a short cycle for
simplicity, in addition, there are no special tricks - 
everything must be absolutely clear. 


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