程式語言 - Netwide Assembler (NASM) - Win32 API - Painting - Create Brush



參考資訊:
https://masm32.com/board/index.php
https://www.nasm.us/xdoc/2.13rc9/html/nasmdoc0.html

繪畫的顏色設定可以分成Brush、Pen兩種,Brush代表填充的顏色,Pen則是線條的顏色

main.asm

    %include "head.asm"
 
    segment .text
WndProc:
    push ebp
    mov ebp, esp
        
    cmp dword [ebp + ARG2], WM_PAINT
    je .handle_paint
    cmp dword [ebp + ARG2], WM_CLOSE
    je .handle_close
    cmp dword [ebp + ARG2], WM_DESTROY
    je .handle_destroy
    jmp .handle_default
   
.handle_paint:
    push ps
    push dword [ebp + ARG1]
    call BeginPaint
    mov [hDC], eax
 
    push 0ffh
    call CreateSolidBrush
    mov [hBrush], eax
 
    push dword [hBrush]
    lea eax, [ps]
    add eax, PAINTSTRUCT.rcPaint
    push eax
    push dword [hDC]
    call FillRect
 
    push ps
    push dword [ebp + ARG1]
    call EndPaint
 
    push dword [hBrush]
    call DeleteObject
    xor eax, eax
    jmp .finish
   
.handle_close:
    push dword [ebp + ARG1]
    call DestroyWindow
    xor eax, eax
    jmp .finish
        
.handle_destroy:
    push 0
    call PostQuitMessage
    xor eax, eax
    jmp .finish
        
.handle_default:
    push dword [ebp + ARG4]
    push dword [ebp + ARG3]
    push dword [ebp + ARG2]
    push dword [ebp + ARG1]
    push dword [pDefWndProc]
    call CallWindowProc
        
.finish:
    leave
    ret 16
        
WinMain:
    push ebp
    mov ebp, esp
         
    push 0
    push 0
    push 0
    push 0
    push 300
    push 300
    push 0
    push 0
    push WS_OVERLAPPEDWINDOW | WS_VISIBLE
    push szAppName
    push WC_DIALOG
    push WS_EX_LEFT
    call CreateWindowEx
    mov [hWin], eax
        
    push WndProc
    push GWL_WNDPROC
    push dword [hWin]
    call SetWindowLong
    mov [pDefWndProc], eax
     
.loop:
    push 0
    push 0
    push 0
    push msg
    call GetMessage
    cmp eax, 0
    je .exit
         
    push msg
    call DispatchMessage
    jmp .loop
         
.exit:
    mov eax, [msg + MSG.wParam]
    leave
    ret 16
         
_start:
    push 0
    call GetModuleHandle
    mov [hInstance], eax
         
    call GetCommandLine
    mov [pCommand], eax
         
    push SW_SHOWNORMAL
    push dword [pCommand]
    push 0
    push dword [hInstance]
    call WinMain
         
    push eax
    call ExitProcess

Line 22~24:產生一個紅色的Brush
Line 26~31:將可視區域填入紅色
Line 37~38:釋放資源

完成