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add generic functions & affine mouse drivers

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This commit is contained in:
Frater 2026-01-08 21:36:51 +01:00
commit 892da28db7
6 changed files with 443 additions and 235 deletions
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58
src/drivers/gfx_cgam.asm
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@ -34,7 +34,6 @@
%define CGA_ODD_BANK 0x2000
%define BG16_SIZE 48
; ------------------------------------------------------------
; initialise le mode graphique (via l'int 10h)
;
@ -42,7 +41,7 @@
; ------------------------------------------------------------
gfx_init:
; init graphics mode
mov ah, 0x00 ; AH=00h set video mode
mov ah, 0x00 ; AH=00h set video mode
mov al, GFX_MODE
int 0x10
@ -56,46 +55,47 @@ gfx_init:
; In:
; CX = x (0..639)
; DX = y (0..199)
; AL = color (0=black, !=0=white)
; BL = color (0=black, !=0=white)
;
; ------------------------------------------------------------
gfx_putpixel:
push bx
push ax
push di
push es
mov ax, VIDEO_SEG
mov es,ax
mov ax, VIDEO_SEG
mov es, ax
; calcul de l'offset 'y':
; si y est impaire, DI+=0x2000
; DI = (y>>1)*80 + (x>>3) + (y&1)*0x2000
mov ax, dx
shr ax, 1 ; ax = y/2
; DI = (y>>1)*80 + (x>>3) + (y&1)*0x2000
mov bx, dx
and bx, 1 ; BX = y&1
mov di, ax ; di = y/2
shl di, 4 ; di = (y/2)*16
mov ax, dx
shr ax, 1 ; AX = y>>1
mov di, ax
mov ax, di
mov di, CGA_STRIDE
mul di ; DX:AX = (y>>1)*80
mov di, ax
test bx, 1
jz .bank_ok
shl ax, 6 ; ax = (y/2)*64
add di, ax ; di = (y/2)*(16+64) = *80
mov ax, cx ; x
shr ax, 3 ; AX = x/8
add di, ax
; ligne paire/impaire
test dl, 1
jz .ligne_paire
add di, CGA_ODD_BANK
.bank_ok:
mov ax, cx
shr ax, 3 ; AX = x>>3
add di, ax
.ligne_paire:
; masque bit = 0x80 >> (x&7)
mov bl, cl
and bl, 7 ; BL = x&7
and cl, 7 ; cl = x&7
mov ah, 080h
mov cl, bl
shr ah, cl ; AH = bitmask
shr ah, cl ; AH = bitmask
; write
cmp al, 0
cmp bl, 0
je .clear
.set:
@ -109,7 +109,7 @@ gfx_putpixel:
.done:
pop es
pop di
pop bx
pop ax
ret
; ------------------------------------------------------------