如何在 windows tasm dosbox 中读取图像文件并在屏幕上显示

回到 MS-DOS 时代，我使用带有调色板的 256 色 PCX 图像，因为我使用了 256 色视频模式.这里NASM LINEZ游戏示例:Im currently learning graphical programming in tasm using dosbox. Ive been using a bunch of loops to draw square blocks of pixels and its really hard. I want to know if theres a way to read an image and display it. I know how to read a txt file maybe this is a start. Pls help 解决方案 You need to write/use image loader or use your own image file format. BMP may look simple but has too much in it like compression pixel formats etc but you still can focus on a specific type of BMP and ignore all the others...Back in the days of MS-DOS I was using 256 color PCX images with palette as I used 256 color video modes. Here NASM LINEZ game example:Color Lines - simple game in C++/the checking algorithmsee the pcx: subroutine. It decodes loaded PCX file from memory ds:0 to raw VGA image at es:di. Beware it does support just 64 KByte size limit !!!Now to visualize the image you would have to copy es:di content into VideoRAM (assuming A000:0000) for example with rep movsd or you can set es:di to it in the first place (but that could flicker).This PCX loader however does not use palette from the image so you need to encode it ... (the routines to change VGA palette are included in the source you just need to extract the RGB values from PCX I think it was at the end of file) Look here:my C++ PCX loader with paletteif converts PCX to 32bit raw image.For more info about MS-DOS game programing see PCGPE 1.0Here another game example (TASM) which uses own image file-format:What is the best way to move an object on the screen?It has text menues, binary file access, 320x200 sprite graphics, 3 human players[Edit1] New codeI removed the old code example and instead I created compilable and working 8bit PCX with color palette viewer in TASM. It uses VESA 800x600x256 colors mode (103h).The image must fit into screen and its file size must be less than 64 KByte !!!I did not add any checks or error messages ... It simply loads file image.pcx and displays it on VESA then wait on key hit end exit. Here the TASM source:PCX.ASM;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; .386 IDEAL MODEL TINY;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; DATASEGfile: db 'image.pcx',0 ;filename to loadbuff:;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; CODESEG STARTUPCODE scrxs equ 800 scrys equ 600 mov ax,103h ; VESA 800x600x256 call vesamod mov al,0 call vesapag; scrxs equ 320; scrys equ 200; mov ax,19 ; VGA 320x200x256; int 10h lea dx,[file] ; load PCX into DS:buff, CX bytes call fopen lea dx,[buff] mov cx,64000 ; some max value to fit into DS segment call fread ; CX is PCX real size call fclose lea si,[buff] ; decode directly to VRAM mov ax,0A000h mov es,ax mov di,0 call pcxmainl0: mov ax,256 ; test keyboard int 16h jz mainl0 sub ax,ax ; clear key buffer int 16h mov ax,3 ;|VGA 80x25 text int 16 ret;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;vesamod:pusha ;set VESA videomode ax mov bx,ax mov ax,4f02h int 16 popa ret;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;vesapag:pusha ;al=page switch vesa video page window A mov [cs:scrpag],al mov dl,al sub dh,dh sub bx,bx mov ax,4f05h ; window A int 16 popa ret;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; .386Pscrpag db 0;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; .386Phand dw 0 ;### handler...ferr db 0 ;### DOS error code;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;fopen: pusha ;DS:DX = file name, [hand] <= file handle mov ax,3D02h int 21h mov bl,0 jnc fopen0 mov bl,al sub ax,axfopen0: mov [cs:hand],ax mov [cs:ferr],bl popa ret;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;fclose: pusha ;[hand] = file handle mov bx,[cs:hand] mov ah,3eh int 21h mov bl,0 jnc fclose0 mov bl,al sub ax,axfclose0:mov [cs:ferr],bl mov [cs:hand],ax popa ret;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;fread: pusha ;DS:DX = adr, CX = lenght, [hand] = hand, CX => read mov bx,[cs:hand] mov ah,3Fh int 21h mov bl,0 jnc fread0 mov bl,al sub ax,axfread0: mov [cs:ferr],bl mov [cs:freadsz],ax popa mov cx,[cs:freadsz] retfreadsz dw 0;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;pcx: pusha ;decode pcx at ds:si to es:di cx = PCX size push ds push es push ecx push edx push si ;set palette add si,cx sub si,768 sub ax,axpall0: mov dx,3C8h mov al,ah out dx,al inc dx lodsb shr al,2 out dx,al lodsb shr al,2 out dx,al lodsb shr al,2 out dx,al inc ah jnz pall0 pop si mov ax,[ds:si+8] ;get xs sub ax,[ds:si+4] inc ax mov [cs:pcxxs],ax mov [cs:pcxx],ax mov ax,[ds:si+10] ;get ys sub ax,[ds:si+6] inc ax mov [cs:pcxys],ax mul [cs:pcxxs] push dx push ax pop edx add si,128 ;src start after pcx header sub ecx,ecx ;RLE decoder of PCXpcxl0: lodsb mov cx,1 cmp al,192 jb pcxr0 mov cl,al and cl,63 lodsbpcxr0: mov bx,cxpcxl1: call point dec [cs:pcxx] ;correct next screen line position if end of PCX line jnz pcxr1 mov ax,[cs:pcxxs] mov [cs:pcxx],ax neg ax add ax,scrxs add di,ax jnc pcxr1 ; page swith mov al,[cs:scrpag] inc al call vesapagpcxr1: loop pcxl1 mov cx,bx sub edx,ecx jz pcxesc jnc pcxl0pcxesc: pop edx pop ecx pop es pop ds popa retpcxxs dw 0 ;PCX resolutionpcxys dw 0pcxx dw 0 ;actual X coordinate;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;point: mov [es:di],al ;point ;estosb inc di jnz pntesc ; page swith mov al,[cs:scrpag] inc al call vesapagpntesc: ret;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; END;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;So take any image up to 800x600 convert it to 256 color PCX with palette and rename it to image.pcx. Then place it to your *.com file and run. I compiled it with Volcov commander extension script vc.ext like this:asm:@c:languagecompilasmasm !.! /ic:languagesourceasminc @c:languagecompilasmlink !.obj /t /x @del !.objso each time I hit the enter on any asm file it will compile. Just change the paths and if you are not targeting *.com files then change the /t switch accordingly. Here preview from my DOSBox: 这篇关于如何在 windows tasm dosbox 中读取图像文件并在屏幕上显示的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！ 上岸，阿里云！