ZX Forum #04 19 ноября 1997

Программирование

screen effects - changed the character set for the original stylized font from the game Rockstar.

            ROCKSTAR


   We have found the disk version of the program, adapted from 
Valentine Ozerov in 1992, participants will focus on

it. First, consider a procedure that performs the modification 
character set for the original stylized font. 


   Listing procedures:
1420.
61B4 21003D LD HL, # 3D00
61B7 118890 LD DE, # 9088
61BA 010003 LD BC, # 0300
61BD EDB0 LDIR
61BF 218790 LD HL, # 9087
61C2 1E60 LD E, # 60
61C4 1D DEC E
61C5 0604 LD B, # 04
61C7 23 INC HL
61C8 05 DEC B
61C9 7E LD A, (HL)
61CA 4F LD C, A
61CB 0F RRCA
61CC B1 OR C
61CD 77 LD (HL), A
61CE 1978 LD A, B
61CF FE00 CP # 00
61D1 C2C761 JP NZ, # 61C7
61D4 0604 LD B, # 04
61D6 23 INC HL
61D7 05 DEC B
61D8 7E LD A, (HL)
61D9 0F RRCA
61DA 4F LD C, A
61DB 07 RLCA
61DC 2007 RLCA
61DD B1 OR C
61DE 77 LD (HL), A
61DF 1978 LD A, B
61E0 FE00 CP # 00
61E2 C2D661 JP NZ, # 61D6
61E5 7B LD A, E
61E6 FE00 CP # 00
61E8 C2C461 JP NZ, # 61C4
61EB 21888F LD HL, # 8F88
61EE 22365C LD (# 5C36), HL
61F1 C9 RET
2

   Start procedure happens to
load address: RANDOMIZE USR
25012. The number of the team at 61B7H, given in the register
DE, determines the address where
will be formation
stylized character set - 9088H (37000). Initially, the 
character being transferred here a set of ROMs. If you want to

change this address, please note that we must at the same time 
change the number in the team at 61BFH - it is per unit less 
than the beginning of a character set.


   Numerical parameter in the command
at 61C2H determines the number of characters for which will be
the conversion - 96.
Modification of the upper half
character is at address
61C5H on 61D1H, the lower half of the symbol: c 61D4H on 61E2H
inclusive.

   After the formation of
new character set will be
completed, it switches to his system variable CHARS. You can, 
depending on the circumstances, to exclude changes CHARS, 
scoring NOP-s team at 61EEH.



   To obtain block codes on
modification of the character set
You can use Beysikprogrammoy:


   1 READ ram: CLEAR ram: READ f
$: READ st: READ len: FOR a = st T
O st + len-1: READ b: POKE a, b: NE
XT a: SAVE f $ CODE st, len

  1910 DATA 25011, "ro1", 25012,62
 100 DATA
033,000,061,017,136,144,001,000,
003,237,176,033,135,144,030,096,
029,006,004,035,005,126,079,015,
177,119,120,254,000,194,199,097
 110 DATA
006,004,035,005,126,015,079,007,
007,177,119,120,254,000,194,214,
097,123,254,000,194,196,097,033,
136,143,034,054,092,201