漸層字

#include <windows.h>

enum {W=800, H=600};
HBITMAP hBmp;
HWND    hwnd;
HDC     hdc, hdcMem;
UCHAR*  pic;


//將 c1 與 c2 以 nc1:nc-nc1 比例混色, 傳回 BGR 格式

inline int mixColor (int c1, int c2, int nc1, int nc)
{
   int a = nc - nc1; typedef UCHAR U;
   int r = (U(c1>>16)*nc1 + U(c2>>16)*a)/ nc;
   int g = (U(c1>>8) *nc1 + U(c2>>8) *a)/ nc;
   int b = (U(c1)    *nc1 + U(c2)    *a)/ nc;
   return (b<<16)|(g<<8)|r;
}

//在 (tx, ty) 處秀出字型=face, 大小=size 的文字 s, 顏色由 c1 過渡到 c2,

void show_text (int tx, int ty, wchar_t* s, int c1, int c2,
                int size=24, wchar_t* face = L"標楷體")                           
{   
    static int bits = GetDeviceCaps (hdc, BITSPIXEL) *
                      GetDeviceCaps (hdc, PLANES);
    HFONT   font    = CreateFont (size,0,0,0,FW_BOLD,0,0,0,0,0,0,0,0,face);
    HGDIOBJ oldFont = SelectObject (hdcMem, font);
    SetBkColor (hdcMem,0);
    SetTextColor (hdcMem, 93);
    TextOut (hdcMem, 0,0, s, wcslen(s));
    SelectObject (hdcMem, oldFont);     
    DeleteObject (font);
   
    int p,x,y, h = size, w = size * wcslen(s);
    if (w > W) w = W;
    if (h > H) h = H;

    BITMAPINFO info0 = {{40, w, h, 1, bits, 0,0,0,0,0,0}, {{0}}};
    GetDIBits (hdcMem, hBmp, 0, h, pic, &info0, DIB_RGB_COLORS);

    if (bits == 32) {
        int *o = (int*) pic;
        for (p=y=0; y<h; ++y, p+=w)
            for (x=0; x<w; ++x)
                if (RGB(0,0,93) == o[p+x])
                    o[p+x] = mixColor (c1,c2, y,h);
                else o[p+x] = 0;            
    }
    BITMAPINFO info = {{40, w, h, 1, bits, 0,0,0,0,0,0}, {{0}}};
    SetDIBitsToDevice (hdc, tx,ty,w,h, 0,0,0,h, pic, &info, DIB_RGB_COLORS);
}

void init()
{
    SetConsoleTitle (L"Conso");
    SMALL_RECT size = {0, 0, W-1, H-1};      
    SetConsoleWindowInfo (GetStdHandle (STD_OUTPUT_HANDLE), TRUE, &size);  
   
    hdc    = GetDC (hwnd = FindWindowW (0, L"Conso"));
    hdcMem = CreateCompatibleDC (hdc);
    hBmp   = CreateCompatibleBitmap (hdc, W, H);     
    pic    = new UCHAR[W*H];
    SelectObject (hdcMem, hBmp);   
}
void free()
{
    delete[] pic;
    ReleaseDC (hwnd, hdc);
    DeleteObject (hBmp);
    DeleteDC (hdcMem);   
}

int main (/* daviddr 081104 */)
{
    init();   
    show_text (30,80, L"漸層字!", RGB(255,10,10), RGB(255,250,50));
    show_text (30,120, L"這是48號字體", RGB(55,10,220), RGB(255,90,90), 48);
    system ("pause");
    free();
    return 0;
}