;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; SPDX-License-Identifier: GPL-2.0-only
; A MoveBack demo
; Copyright (C) 2010-2025 KolibriOS team
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

include "../../macros.inc"
include "../../KOSfuncs.inc"

KOS_APP_START

Screen_W    dd 600-10 ;10 px for borders
Screen_H    dd 400

VC_DELTA = 1
HC_DELTA = 2


CODE
    mcall SF_SYS_MISC,SSF_HEAP_INIT
    call OnResize
    fninit
    call init_sinus_table
    call init_background
    call init_palette
    mcall SF_SET_EVENTS_MASK, 101b
    jmp .paint_window

align 4
.event_loop:
    mcall SF_WAIT_EVENT_TIMEOUT, 1

    test eax,eax
    je .draw_screen
    dec eax
    je .paint_window

    mcall SF_TERMINATE_PROCESS

.draw_screen:
    test [proc_info.wnd_state], 0x04
    jnz .event_loop
    add word [ver_counter],VC_DELTA
    add word [hor_counter],HC_DELTA
    call handle_animation
    xor ebp,ebp
    mov ecx,[Screen_W]
    shl ecx,16
    add ecx,[Screen_H]
    mcall SF_PUT_IMAGE_EXT, [virtual_screen_8],,<0,0>,8,_palette
    jmp .event_loop

.paint_window:
    mcall SF_THREAD_INFO, proc_info,-1
    cmp dword[proc_info.box.height],0
    je .resize_end
    mcall SF_STYLE_SETTINGS, SSF_GET_SKIN_HEIGHT
    add eax,4
    sub eax,[proc_info.box.height]
    neg eax
    cmp eax,[Screen_H]
    je .end_h
    cmp eax,32 ;min height
    jge @f
        mov eax,32
    @@:
    mov [Screen_H],eax
    xor eax,eax
    mov [Screen_W],eax
    .end_h:
    
    mov eax,[proc_info.box.width]
    sub eax,9
    cmp eax,[Screen_W]
    je .resize_end
    cmp eax,64 ;min width
    jge @f
        mov eax,64
    @@:
    mov [Screen_W],eax

    call OnResize
    .resize_end:

    mcall SF_REDRAW, SSF_BEGIN_DRAW

    mcall SF_STYLE_SETTINGS, SSF_GET_SKIN_HEIGHT
    lea ecx,[eax + (100 shl 16) +4]
    add ecx,[Screen_H]
    mov edi,title
    mov ebx,(100 shl 16)+9
    add ebx,[Screen_W]
    mcall SF_CREATE_WINDOW,,,0x73000000

    test [proc_info.wnd_state], 0x04
    jnz @f

    xor ebp,ebp
    mov ecx,[Screen_W]
    shl ecx,16
    add ecx,[Screen_H]
    mcall SF_PUT_IMAGE_EXT, [virtual_screen_8],,<0,0>,8,_palette
@@:
    mcall SF_REDRAW, SSF_END_DRAW

    jmp .event_loop

init_palette:
    mov ecx,256
    mov edi,_palette
    xor eax,eax
.next_pal:
    mov al,ah
    shr al,2
    stosb
    stosb
    stosb
    stosb
    inc ah
    loop .next_pal
    ret

init_sinus_table:
    sub esp,4
    mov ecx,256
    mov edi,sinetable
.sin_loop:
    fld dword [esp]
    fld st0
    fsin
    fmul [scale_sin]
    fistp word [edi]
    fadd [delta_angle]
    fstp dword [esp]
    add edi,2
    loop .sin_loop
    add esp,4
    ret

init_background:
    mov edi,background
    xor edx,edx
.ib_vertical:
    xor ecx,ecx
.ib_horizontal:
    mov eax,ecx
    xor eax,edx
    stosb
    inc ecx
    cmp ecx,256
    jne .ib_horizontal
    inc edx
    cmp edx,256
    jne .ib_vertical
    ret

align 4
OnResize:
    mov ecx,[Screen_W]
    imul ecx,[Screen_H]
    mcall SF_SYS_MISC,SSF_MEM_REALLOC,,[virtual_screen_8]
    mov [virtual_screen_8],eax
    ret

s_OFFX    = 0
s_OFFY    = 2

handle_animation:
    sub esp,4
    mov ebx,[ver_counter]
    and ebx,255
    add ebx,ebx
    mov ax,[sinetable+ebx]
    mov [esp+s_OFFY],ax
    mov ebx,[hor_counter]
    and ebx,255
    add ebx,ebx
    mov ax,[sinetable+ebx]
    mov [esp+s_OFFX],ax
    mov edi,[virtual_screen_8]
    mov edx,[Screen_H]
    dec edx
.a_ver:
    mov ecx,[Screen_W]
    dec ecx
    mov bx,[esp+s_OFFY]
    add bx,dx
    and ebx,255
    shl ebx,8
.a_hor:
    mov ax,[esp+s_OFFX]
    add ax,cx
    and eax,255
    mov al,[background+ebx+eax]
    stosb
    dec ecx
    jge .a_hor
    dec edx
    jge .a_ver
    add esp,4
    ret

DATA
    delta_angle dd 0.0245436926066        ; pi/128
    scale_sin dd 128.0

    title    db 'MoveBack',0

UDATA
    ver_counter dd ?
    hor_counter dd ?

    _palette:    rd 256

    virtual_screen_8 dd ?

background:
    rb 256*256

sinetable:
    rw 256

    proc_info    process_information

KOS_APP_END