Changes

'''Forrest Picture''' is a picture drawn by [[Mr. Lou]]s girlfriend, and is a demonstration on how to use the graphic abilities of the CPC. The picture uses [[mode 1]] of the CPC. The graphic mode is limited to 4 simultanious colors.

The picture uses [[Image:Forrest originalmode 1]] of the CPC.gifThe graphic mode is limited to 4 simultanious colors. After publication the picture became the subject on how to break the 4 colour limit in mode 1 using [[rasters]]. Subsequent [[T&J|320pxTom & Jerry of GPA]]wrote a small program showing how the picture would look like using rasters generated by the [[gate array]].

''Original picture'' [[Image:Forrest original.gif|320px|Picture drawn by Mr. Lous girlfriend]] ''Picture using rasters'' [[Image:Forrest raster version.png|320px|Picture using raster routine by T&J]] == Sourcecode ==  <geshi lang=z80>; Example of rasters in a MODE 1 screen; T&J/GPA in 2009 ; Done under WINAPE; Not tested on a real CPC, so maybe it needs some timing adjustments ; Wait for Color Lines ! Rasters inside !! ORG &9000NOLISTWRITE "RASTERS.BIN" black equ &54grey equ &41green_19 equ &51red_6 equ &4Cblue_1 equ &44blue_11 equ &57blue_14 equ &5Fbleu_clair equ &53 violet equ &58 JP booter save38 defw &0 Booter DI LD HL,(&38) LD (save38),HL LD HL,&C9FB LD (&38),HL EI  main DI LD B,&F5sync IN A,(C) RRA JR NC,sync  CALL scan_spacekey CP &7F JP Z,endit  LD BC,&7F02 ; sky OUT (C),C LD A,blue_11 OUT (C),A  EI  HALT  HALT  LD HL,&FDD0wait1 INC HL LD A,H AND A JR NZ,wait1  LD BC,&7F02 OUT (C),C LD A,&5F OUT (C),A  HALT HALT  LD HL,&FFC0wait2 INC HL LD A,H AND A JR NZ,wait2  LD BC,&7F02 ; board of the lake OUT (C),C LD A,grey OUT (C),A  LD HL,&FF74wait3 INC HL LD A,H AND A JR NZ,wait3  LD BC,&7F02 OUT (C),C  LD D,green_19 LD E,red_6  DI  LD A,&40 split1 OUT (C),E ; red mushrooms PUSH AF NOP NOP NOP NOP NOP OUT (C),D ; green mushroom  NOP NOP NOP  LD A,&9waitsp1 DEC A JR NZ,waitsp1  POP AF DEC A JR NZ,split1  JP main endit   LD BC,&7F02 ; sky OUT (C),C LD A,blue_14 OUT (C),A  LD HL,(save38) DI LD (&38),HL EI RET scan_spacekey  LD BC,&F40E OUT (C),C LD BC,&F6C0 OUT (C),C LD C,&0 OUT (C),C LD BC,&F792 OUT (C),C LD BC,&F645 OUT (C),C LD B,&F4 IN A,(C) LD BC,&F782 OUT (C),C LD BC,&F600 OUT (C),C RET</geshi> == Download ==