[原創]SOUI GDI+渲染引擎下的字體特效，拋磚引玉

由於SOUI是一種雙渲染引擎的DUI庫，默認在SKIA渲染引擎下是支持特效字體的，具體請參考DEMO中的源碼。

但是使用GDI+渲染時是沒有這些特效的，着實比較苦惱，此代拋磚引玉，細節實現 請自己再去封裝，此處只封裝了STATIC控件。

部分效果使用了庫:TextDesigner

CodeProject: http://www.codeproject.com/Articles/42529/Outline-Text

此代碼有一個小BUG，在使用SOUI布局時，POS必須4個參數都指定，類似如此：pos="15,20,-15,@25"

有興趣的朋友可以自己實現一下。

先看下預覽效果：

我只實現了部分效果，由於效果組合太多，所以這里暫時把我常用的先貼出來。

參數說明：

drawMode: 1為描邊 2陰影 3外發光 4雙描邊，具體特效請自己設置顏色和渲染效果

EffectColor: 特效的顏色數值

EffectColor2: 使用雙效果時的第二個數值顏色

底層使用GDI+所以默認支持多行，但是請根據多行來設置對應的高寬，否則顯示肯定錯誤。

頭文件：

/*!
 * \file SEffectStatic.h
 * \date 2016/02/15 19:51
 *
 * \author koangel
 * Contact: [e-mail]
 * blog: http://www.cnblogs.com/koangel/
 *
 * \brief GDI渲染模式下專用靜態特效渲染庫 
 *
 * \note GDI+渲染模式下專用，如果在SKIA模式下，直接切換為標准SSTAIC模式渲染
 *          效果使用GDI編寫，暫不支持SKIA
 *        部分效果使用TextDesigner庫編寫。
 *          CodeProject: http://www.codeproject.com/Articles/42529/Outline-Text
 *          TextDesigner版權歸原作者所有。
*/
#pragma once
#include <gdiplus.h>

#pragma comment(lib,"gdiplus.lib")

class SEffectStatic : public SStatic
{
    SOUI_CLASS_NAME(SStatic, L"eff_text")
public:
    SEffectStatic();
    virtual ~SEffectStatic();
    /**
    * SStatic::SDrawText
    * @brief    繪制文本
    * @param    IRenderTarget *pRT -- 繪制設備句柄
    * @param    LPCTSTR pszBuf -- 文本內容字符串
    * @param    int cchText -- 字符串長度
    * @param    LPRECT pRect -- 指向矩形結構RECT的指針
    * @param    UINT uFormat --  正文的繪制選項
    *
    * Describe  對DrawText封裝
    */
    virtual void DrawText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat);

protected:

    void DrawMultiLine(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat);
    void DrawShadowMultiLine(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat);

    // 渲染帶陰影的字體
    void DrawShadowText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat);
    void DrawStrokeText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat);
    void DrawDoubleStrokeText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat);
    void DrawGowText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat);

    void    initGDIFont(IRenderTarget *pRT,Gdiplus::Font& gf);

    LOGFONT*    GetGDIFont(IRenderTarget *pRT);
    Gdiplus::StringFormat*    toFormat(UINT uFormat);

    int            m_nEffectDrawMode;            /**< 渲染模式 */
    COLORREF    m_nEffectColor;            /**< 效果顏色 */
    COLORREF    m_nEffectColor2;            /**< 效果顏色 */
    WORD        m_StrokeSize;                /**< 描邊大小 */

    SOUI_ATTRS_BEGIN()
        ATTR_INT(L"drawMode", m_nEffectDrawMode, FALSE)
        ATTR_COLOR(L"effectColor", m_nEffectColor, FALSE)
        ATTR_COLOR(L"effectColor2", m_nEffectColor2, FALSE)
        ATTR_INT(L"strokeSize", m_StrokeSize, FALSE)
    SOUI_ATTRS_END()
};

實現文件：

/*!
 * \file SEffectStatic.cpp
 * \date 2016/02/16 13:00
 *
 * \author koangel
 * Contact: [e-mail]
 *
 * \brief 渲染對應的靜態文本，多行文本渲染可能存在問題
 *
 * TODO: blog http://www.cnblogs.com/koangel/
 *
 * \note
*/
#include "stdafx.h"
#include "SEffectStatic.h"
enum DRAW_EFFECT_MODE
{
    DRAW_TEXT_NORMAL = 0, // 默認渲染
    DRAW_TEXT_STROKE, // 渲染 描邊
    DRAW_TEXT_SHADOW, // 渲染 陰影
    DRAW_TEXT_GROW,    // 渲染 外發光效果
    DRAW_TEXT_DBSTROKE, // 渲染 雙描邊
};

#define GR(rgb)      ((BYTE)(rgb))
#define GG(rgb)      ((BYTE)(((WORD)(rgb)) >> 8))
#define GB(rgb)      ((BYTE)((rgb)>>16))

// 默認調用之前的構造函數
SEffectStatic::SEffectStatic() : SStatic(),
    m_nEffectColor(0xFFFFFF),
    m_nEffectColor2(0xFF0080),
    m_nEffectDrawMode(0),
    m_StrokeSize(1)
{
}


SEffectStatic::~SEffectStatic()
{

}

void SEffectStatic::DrawText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat)
{
    if (!m_bMultiLines)
    {
        switch (m_nEffectDrawMode)
        {
        case DRAW_TEXT_NORMAL:
            __super::DrawText(pRT, pszBuf, cchText, pRect, uFormat);
            break;
        case DRAW_TEXT_STROKE:
            DrawStrokeText(pRT, pszBuf, cchText, pRect, uFormat);
            break;
        case DRAW_TEXT_SHADOW:
            DrawShadowText(pRT, pszBuf, cchText, pRect, uFormat);
            break;
        case DRAW_TEXT_GROW:
            DrawGowText(pRT, pszBuf, cchText, pRect, uFormat);
            break;
        case DRAW_TEXT_DBSTROKE:
            DrawDoubleStrokeText(pRT, pszBuf, cchText, pRect, uFormat);
            break;
        }
    }
    else
    {
        switch (m_nEffectDrawMode)
        {
        case DRAW_TEXT_NORMAL:
        {
            if (uFormat&(DT_VCENTER | DT_BOTTOM) && !(uFormat & DT_CALCRECT))
            {
                //static 多行控件支持垂直居中及底對齊
                CRect rcText = *pRect;
                DrawMultiLine(pRT, pszBuf, cchText, &rcText, uFormat | DT_CALCRECT);
                CSize szTxt = rcText.Size();
                rcText = *pRect;
                switch (GetStyle().GetTextAlign()&(DT_VCENTER | DT_BOTTOM))
                {
                case DT_VCENTER:
                    rcText.DeflateRect(0, (rcText.Height() - szTxt.cy) / 2);
                    break;
                case DT_BOTTOM:
                    rcText.DeflateRect(0, (rcText.Height() - szTxt.cy));
                    break;
                }
                DrawMultiLine(pRT, pszBuf, cchText, &rcText, uFormat);
            }
            else
            {
                DrawMultiLine(pRT, pszBuf, cchText, pRect, uFormat);
            }
            break;
        }
        case DRAW_TEXT_STROKE:
            DrawStrokeText(pRT, pszBuf, cchText, pRect, uFormat);
            break;
        case DRAW_TEXT_SHADOW:
            DrawShadowMultiLine(pRT, pszBuf, cchText, pRect, uFormat);
            break;
        case DRAW_TEXT_GROW:
            DrawGowText(pRT, pszBuf, cchText, pRect, uFormat);
            break;
        case DRAW_TEXT_DBSTROKE:
            DrawDoubleStrokeText(pRT, pszBuf, cchText, pRect, uFormat);
            break;
        }    
    }
}

void SEffectStatic::DrawMultiLine(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat)
{
    SIZE szChar;
    int i = 0, nLine = 1;
    if (cchText == -1) cchText = _tcslen(pszBuf);
    LPCTSTR p1 = pszBuf;
    POINT pt = { pRect->left,pRect->top };
    pRT->MeasureText(_T("A"), 1, &szChar);
    int nLineHei = szChar.cy;
    int nRight = pRect->right;
    pRect->right = pRect->left;
    while (i<cchText)
    {
        LPTSTR p2 = CharNext(p1);
        if (*p1 == _T('\\') && p2 && *p2 == _T('n'))
        {
            pt.y += nLineHei + m_nLineInter;
            pt.x = pRect->left;
            nLine++;
            i += p2 - p1;
            p1 = CharNext(p2);
            i += p1 - p2;
            continue;
        }
        pRT->MeasureText(p1, p2 - p1, &szChar);
        if (pt.x + szChar.cx > nRight)
        {
            pt.y += nLineHei + m_nLineInter;
            pt.x = pRect->left;
            nLine++;
            continue;
        }
        if (!(uFormat & DT_CALCRECT))
        {
            pRT->TextOut(pt.x, pt.y, p1, p2 - p1);
        }
        pt.x += szChar.cx;
        if (pt.x > pRect->right && uFormat & DT_CALCRECT) pRect->right = pt.x;
        i += p2 - p1;
        p1 = p2;
    }
    if (uFormat & DT_CALCRECT)
    {
        pRect->bottom = pt.y + nLineHei;
    }
}

void SEffectStatic::DrawShadowMultiLine(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat)
{
    COLORREF textColor = this->m_style.GetTextColor(0);

    Gdiplus::StringFormat   *strFmt = toFormat(uFormat);

    Gdiplus::Graphics           gs(pRT->GetDC());
    Gdiplus::Font               gf(pRT->GetDC(), GetGDIFont(pRT));

    gs.SetSmoothingMode(Gdiplus::SmoothingModeAntiAlias);
    gs.SetTextRenderingHint(Gdiplus::TextRenderingHintAntiAliasGridFit);
    gs.SetPixelOffsetMode(Gdiplus::PixelOffsetModeHighQuality);

    Gdiplus::Rect rectF(pRect->left, pRect->top, pRect->right - pRect->left, pRect->bottom - pRect->top);

    Gdiplus::FontFamily ffamliy;
    gf.GetFamily(&ffamliy);

    Gdiplus::SolidBrush  br1(Gdiplus::Color(255, GR(textColor), GG(textColor), GB(textColor)));

    TextDesigner::OutlineText outtext;
    outtext.EnableShadow(true);
    outtext.TextNoOutline(br1);
    outtext.Shadow(Gdiplus::Color(128, GR(m_nEffectColor), GG(m_nEffectColor), GB(m_nEffectColor)), 2, Gdiplus::Point(1,2));
    outtext.DrawString(&gs, &ffamliy, (Gdiplus::FontStyle) gf.GetStyle(), gf.GetSize(), pszBuf, rectF, strFmt);
}

void SEffectStatic::DrawShadowText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat)
{
    COLORREF textColor = this->m_style.GetTextColor(0);

    Gdiplus::StringFormat   *strFmt = toFormat(uFormat);
    Gdiplus::Graphics           gs(pRT->GetDC());
    Gdiplus::Font               gf(pRT->GetDC(), GetGDIFont(pRT));

    gs.SetSmoothingMode(Gdiplus::SmoothingModeAntiAlias);
    gs.SetTextRenderingHint(Gdiplus::TextRenderingHintAntiAliasGridFit);
    gs.SetPixelOffsetMode(Gdiplus::PixelOffsetModeHighQuality);

    Gdiplus::Rect rectF(pRect->left, pRect->top, pRect->right - pRect->left, pRect->bottom - pRect->top);

    Gdiplus::FontFamily ffamliy;
    gf.GetFamily(&ffamliy);

    Gdiplus::SolidBrush  br1(Gdiplus::Color(255, GR(textColor), GG(textColor), GB(textColor)));

    TextDesigner::OutlineText outtext;
    outtext.EnableShadow(true);
    outtext.TextNoOutline(br1);
    outtext.Shadow(Gdiplus::Color(128, GR(m_nEffectColor), GG(m_nEffectColor), GB(m_nEffectColor)), 2, Gdiplus::Point(1,2));
    outtext.DrawString(&gs, &ffamliy,(Gdiplus::FontStyle) gf.GetStyle(), gf.GetSize() , pszBuf, rectF, strFmt);
}

void SEffectStatic::DrawStrokeText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat)
{
    COLORREF textColor = this->m_style.GetTextColor(0);
    Gdiplus::Graphics           gs(pRT->GetDC());
    Gdiplus::Font               gf(pRT->GetDC(), GetGDIFont(pRT));
    Gdiplus::StringFormat   *strFmt = toFormat(uFormat);

    gs.SetSmoothingMode(Gdiplus::SmoothingModeAntiAlias);
    gs.SetTextRenderingHint(Gdiplus::TextRenderingHintAntiAliasGridFit);
    gs.SetPixelOffsetMode(Gdiplus::PixelOffsetModeHighQuality);

    Gdiplus::RectF rectF(pRect->left, pRect->top, pRect->right - pRect->left, pRect->bottom - pRect->top);

    Gdiplus::SolidBrush  br1(Gdiplus::Color(255,GR(textColor), GG(textColor), GB(textColor)));
    Gdiplus::SolidBrush  br2(Gdiplus::Color(250,GR(m_nEffectColor), GG(m_nEffectColor), GB(m_nEffectColor)));

    int nOffsetX[8] = { 1,1,1,0,-1,-1,-1,0 };
    int nOffsetY[8] = { -1,0,1,1,1,0,-1,-1 };

    for (int i = 0; i < 8;i++)
    {
        Gdiplus::RectF lRecf(rectF);
        lRecf.Offset(nOffsetX[i], nOffsetY[i]);
        gs.DrawString(pszBuf, cchText, &gf, lRecf, strFmt, &br2);
    }

    gs.DrawString(pszBuf, cchText, &gf, rectF, toFormat(uFormat), &br1);
}

void SEffectStatic::DrawDoubleStrokeText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat)
{
    COLORREF textColor = this->m_style.GetTextColor(0);
    Gdiplus::StringFormat   *strFmt = toFormat(uFormat);
    Gdiplus::Graphics           gs(pRT->GetDC());
    Gdiplus::Font               gf(pRT->GetDC(), GetGDIFont(pRT));

    gs.SetSmoothingMode(Gdiplus::SmoothingModeAntiAlias);
    gs.SetTextRenderingHint(Gdiplus::TextRenderingHintAntiAliasGridFit);
    gs.SetPixelOffsetMode(Gdiplus::PixelOffsetModeHighQuality);

    Gdiplus::Rect rectF(pRect->left, pRect->top, pRect->right - pRect->left, pRect->bottom - pRect->top);

    Gdiplus::FontFamily ffamliy;
    gf.GetFamily(&ffamliy);

    Gdiplus::SolidBrush  br1(Gdiplus::Color(255, GR(textColor), GG(textColor), GB(textColor)));

    TextDesigner::OutlineText outtext;
    outtext.EnableShadow(false);
    outtext.TextDblOutline(br1, Gdiplus::Color(255, GR(m_nEffectColor), GG(m_nEffectColor), GB(m_nEffectColor)),
        Gdiplus::Color(255, GR(m_nEffectColor2), GG(m_nEffectColor2), GB(m_nEffectColor2)), 3,3);
    outtext.DrawString(&gs, &ffamliy, (Gdiplus::FontStyle) gf.GetStyle(), gf.GetSize(), pszBuf, rectF, strFmt);
}

void SEffectStatic::DrawGowText(IRenderTarget *pRT, LPCTSTR pszBuf, int cchText, LPRECT pRect, UINT uFormat)
{
    COLORREF textColor = this->m_style.GetTextColor(0);
    Gdiplus::StringFormat   *strFmt = toFormat(uFormat);
    Gdiplus::Graphics           gs(pRT->GetDC());
    Gdiplus::Font               gf(pRT->GetDC(), GetGDIFont(pRT));

    gs.SetSmoothingMode(Gdiplus::SmoothingModeAntiAlias);
    gs.SetTextRenderingHint(Gdiplus::TextRenderingHintAntiAliasGridFit);
    gs.SetPixelOffsetMode(Gdiplus::PixelOffsetModeHighQuality);

    Gdiplus::Rect rectF(pRect->left, pRect->top, pRect->right - pRect->left, pRect->bottom - pRect->top);

    Gdiplus::FontFamily ffamliy;
    gf.GetFamily(&ffamliy);

    Gdiplus::SolidBrush  br1(Gdiplus::Color(255, GR(textColor), GG(textColor), GB(textColor)));

    TextDesigner::OutlineText outtext;
    outtext.EnableShadow(false);
    outtext.TextGlow(br1,Gdiplus::Color(64, GR(m_nEffectColor), GG(m_nEffectColor), GB(m_nEffectColor)),6);
    outtext.DrawString(&gs, &ffamliy, (Gdiplus::FontStyle) gf.GetStyle(), gf.GetSize(), pszBuf, rectF, strFmt);
}

LOGFONT* SEffectStatic::GetGDIFont(IRenderTarget *pRT)
{
    SOUI::IFontPtr pFont = m_style.GetTextFont(0);
    SOUI::IFontPtr pDFont = (SOUI::IFontPtr)pRT->GetCurrentObject(OT_FONT);
    LOGFONT    *    logFont = NULL;
    if (pFont == NULL)
        logFont = (LOGFONT*)pDFont->LogFont();
    else
        logFont = (LOGFONT*)pFont->LogFont();

    return logFont;
}

Gdiplus::StringFormat* SEffectStatic::toFormat(UINT uFormat)
{
    Gdiplus::StringFormat   *strFmt = Gdiplus::StringFormat::GenericTypographic()->Clone();

    if (uFormat&(DT_VCENTER | DT_BOTTOM))
    {
        strFmt->SetAlignment(Gdiplus::StringAlignmentCenter);
        strFmt->SetLineAlignment(Gdiplus::StringAlignmentCenter);
    }
    else
    {
        strFmt->SetAlignment(Gdiplus::StringAlignmentNear);
        strFmt->SetLineAlignment(Gdiplus::StringAlignmentNear);
    }

    return strFmt;
}

以上代碼拋磚引玉，希望各位發揚光大，多寫一些組件庫噢。