| 0,0 → 1,257 |
|---|
| ;;================================================================================================;; |
| ;;//// z80.asm //// (c) Nable, 2007-2008 /////////////////////////////////////////////////////////;; |
| ;;================================================================================================;; |
| ;; ;; |
| ;; This file is part of Common development libraries (Libs-Dev). ;; |
| ;; ;; |
| ;; Libs-Dev is free software: you can redistribute it and/or modify it under the terms of the GNU ;; |
| ;; Lesser General Public License as published by the Free Software Foundation, either version 2.1 ;; |
| ;; of the License, or (at your option) any later version. ;; |
| ;; ;; |
| ;; Libs-Dev is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without ;; |
| ;; even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU ;; |
| ;; Lesser General Public License for more details. ;; |
| ;; ;; |
| ;; You should have received a copy of the GNU Lesser General Public License along with Libs-Dev. ;; |
| ;; If not, see <http://www.gnu.org/licenses/>. ;; |
| ;; ;; |
| ;;================================================================================================;; |
| ;; ;; |
| ;; References: ;; |
| ;; 1. ;; |
| ;; ;; |
| ;;================================================================================================;; |
| |
| include 'z80.inc' |
| |
| ;;================================================================================================;; |
| proc img.is.z80 _data, _length ;//////////////////////////////////////////////////////////////////;; |
| ;;------------------------------------------------------------------------------------------------;; |
| ;? Determine if raw data could be decoded (is in z80 screen format) ;; |
| ;;------------------------------------------------------------------------------------------------;; |
| ;> _data = raw data as read from file/stream ;; |
| ;> _length = data length ;; |
| ;;------------------------------------------------------------------------------------------------;; |
| ;< eax = false / true ;; |
| ;;================================================================================================;; |
| xor eax,eax |
| cmp [_length],6929 |
| setz al |
| je @f |
| cmp [_length],6912 |
| setz al |
| @@: |
| ret |
| endp |
| |
| ;;================================================================================================;; |
| proc img.decode.z80 _data, _length ;//////////////////////////////////////////////////////////////;; |
| ;;------------------------------------------------------------------------------------------------;; |
| ;? Decode data into image if it contains correctly formed raw data in z80 screen format ;; |
| ;;------------------------------------------------------------------------------------------------;; |
| ;> _data = raw data as read from file/stream ;; |
| ;> _length = data length ;; |
| ;;------------------------------------------------------------------------------------------------;; |
| ;< eax = 0 (error) or pointer to image ;; |
| ;;================================================================================================;; |
| ;--------------------------------------------------------------------------------------------------- |
| ;During the decoding: |
| ;bl - PixelLeft (this means how much pixels left to put in current string) |
| ;bh - CurrentString |
| ;High half of ebx - use DualStos (two frames per one pixel_write) |
| ;cl - PixelColorIndexInPalette |
| ;ch - BackgroundColorIndexInPalette |
| ;High half of ecx - blinking flag |
| ;edx - address of current attribute byte |
| ;--------------------------------------------------------------------------------------------------- |
| locals |
| frame1 dd ? |
| OffsetIn2ndFrame dd ? |
| endl |
| xor eax,eax |
| pushad |
| cld ;paranoia |
| stdcall img.create,256,192,Image.bpp8 |
| test eax,eax |
| jz img.decode.z80.locret ;test if allocation failed |
| mov [frame1],eax |
| mov esi,z80._._16color_palette |
| mov ecx,16 |
| mov edi,[eax+Image.Palette] |
| rep movsd ;write palette for the first frame |
| mov esi,[_data] |
| cmp [_length],6929 |
| jne @f |
| add esi,17 ;in case of 6929 byte files we just skip the info in the begininning. |
| @@: |
| ;--------------------------------------------------------------------------------------------------- |
| ;At first we'll determine if there are any blinking pixels |
| ;if no - we'll produce statical single image |
| mov ecx,768 |
| lea edx,[esi+6912-768];edx points to attribute area |
| xor ebx,ebx ;begin from <0,0> (for further decoding) |
| @@: |
| test byte[edx+ecx-1],z80.BlinkFlag ;such addressing is a good optimisation |
| ;(as I hope), edx is unchanged |
| jnz .decode_z80_with_blinking |
| loop @b |
| .decode_z80_without_blinking: |
| jmp .decode_z80_main_stage |
| |
| .decode_z80_with_blinking: |
| or ebx,0xFFFF0000 ;use DualStos |
| mov ecx,eax ;eax still points to the first frame |
| stdcall img.create,256,192,Image.bpp8 |
| test eax,eax |
| jz img.decode.z80.failed |
| mov [eax+Image.Previous],ecx |
| mov [ecx+Image.Next],eax |
| mov esi,z80._._16color_palette |
| mov ecx,16 |
| mov edi,[eax+Image.Palette] |
| rep movsd ;write palette for the second frame |
| mov eax,[eax+Image.Data] |
| mov [OffsetIn2ndFrame],eax |
| ;------------------------------------------------------------------------------- |
| .decode_z80_main_stage: |
| ;2nd stage - convert z80 screen to 8bpp image with palette |
| .decode_z80_main_stage_main_loop: |
| test bl,7 |
| jnz .decode_z80_main_stage_put_now |
| |
| ._z80_update_attributes: |
| movsx ecx,byte[edx] ;note that BlinkFlag is the highest bit in attribute |
| ;byte, so ecx's highest bit is set automatically |
| shl ecx,5 |
| shr cl,5 |
| and ch,0xF |
| test ch,1000b |
| jz @f |
| or ecx,1000b ;it has the same size with 'or cl,1000b' but could be faster |
| @@: |
| inc edx |
| |
| lodsb |
| mov ah,al |
| |
| .decode_z80_main_stage_put_now: |
| shl ah,1 |
| ;------------------------------------------------------------------------------- |
| ._z80_put_pixel: |
| ;In: CF - put pixel with color CL, !CF - pixel with color CH |
| ;High parts of ebx and ecx - as described above |
| mov al,cl ;'mov' doesn't affect flags |
| jc @f |
| mov al,ch |
| @@: |
| stosb ;'stosb' doesn't affect flags |
| |
| test ebx,ebx |
| jns @f |
| test ecx,ecx |
| jns .1 |
| mov al,ch |
| .1: |
| xchg [OffsetIn2ndFrame],edi |
| stosb |
| xchg [OffsetIn2ndFrame],edi |
| @@: |
| inc bl ;next pixel |
| jz .decode_z80_main_stage_row_finished |
| jmp .decode_z80_main_stage_main_loop |
| ;------------------------------------------------------------------------------- |
| .decode_z80_main_stage_row_finished: |
| cmp bh,191 ;is image finished? |
| jb .decode_z80_main_stage_image_not_finished ;no. |
| .decode_z80_finish: |
| jmp .locret ;now really finished |
| ;------------------------------------------------------------------------------- |
| ;or not finished yet. Branch according to a row number (see documentation) |
| .decode_z80_main_stage_next_third: |
| sub bh,7 |
| sub edi,256*(8-1) |
| jmp .decode_z80_main_stage_main_loop |
| |
| .decode_z80_main_stage_image_not_finished: |
| ;next row |
| add bh,8 ;refer to documentation |
| add edi,256*(8-1) |
| |
| ;if finished row is 63 or 127 then we process next third of the image |
| cmp bh,63+8 |
| je .decode_z80_main_stage_next_third |
| cmp bh,127+8 |
| je .decode_z80_main_stage_next_third |
| |
| cmp bh,56+8 ;if finished row in [56;63) or [120;127) or [184;191) |
| jb .decode_z80_main_stage_main_loop |
| cmp bh,63+8 |
| jb .4 |
| cmp bh,120+8 |
| jb .decode_z80_main_stage_main_loop |
| cmp bh,127+8 |
| jb .4 |
| cmp bh,184+8 |
| jb .decode_z80_main_stage_main_loop |
| ;note that if we are here then bh is < 191 (see label .2) but >= 184+8 |
| .4: |
| ;and if we here then bh is in [56;63) or [120;127) or [184;191) |
| sub bh,(8+56-1) |
| sub edi,256*(8+56-1) |
| sub edx,z80.AttrString*8 |
| jmp .decode_z80_main_stage_main_loop |
| img.decode.z80.locret: |
| popad |
| ret |
| img.decode.z80.failed: |
| stdcall img.destroy,[frame1] |
| jmp img.decode.z80.locret |
| endp |
| |
| ;;================================================================================================;; |
| proc img.encode.z80 _img, _p_length ;/////////////////////////////////////////////////////////////;; |
| ;;------------------------------------------------------------------------------------------------;; |
| ;? Encode image into raw data in z80 screen format ;; |
| ;;------------------------------------------------------------------------------------------------;; |
| ;> _img = pointer to image ;; |
| ;;------------------------------------------------------------------------------------------------;; |
| ;< eax = 0 (error) or pointer to encoded data ;; |
| ;< _p_length = encoded data length ;; |
| ;;================================================================================================;; |
| xor eax, eax |
| ret |
| endp |
| |
| |
| ;;================================================================================================;; |
| ;;////////////////////////////////////////////////////////////////////////////////////////////////;; |
| ;;================================================================================================;; |
| ;! Below are private procs you should never call directly from your code ;; |
| ;;================================================================================================;; |
| ;;////////////////////////////////////////////////////////////////////////////////////////////////;; |
| ;;================================================================================================;; |
| |
| ;;================================================================================================;; |
| ;;////////////////////////////////////////////////////////////////////////////////////////////////;; |
| ;;================================================================================================;; |
| ;! Below is private data you should never use directly from your code ;; |
| ;;================================================================================================;; |
| ;;////////////////////////////////////////////////////////////////////////////////////////////////;; |
| ;;================================================================================================;; |
| z80._._16color_palette: |
| dd 0 ; black |
| dd 0x000000b0 ; blue |
| dd 0x00b00000 ; red |
| dd 0x00b000b0 ; magenta |
| dd 0x0000b000 ; green |
| dd 0x0000b0b0 ; cyan |
| dd 0x00b0b000 ; yellow |
| dd 0x00b0b0b0 ; gray |
| dd 0 ; black |
| dd 0x000000ff ; light blue |
| dd 0x00ff0000 ; light red |
| dd 0x00ff00ff ; light magenta |
| dd 0x0000ff00 ; light green |
| dd 0x0000ffff ; light cyan |
| dd 0x00ffff00 ; light yellow |
| dd 0x00ffffff ; white |