C++ CFX_DIBitmap::Clear方法代码示例

static CFX_DIBitmap* DrawPatternBitmap(CPDF_Document* pDoc,
                                       CPDF_PageRenderCache* pCache,
                                       CPDF_TilingPattern* pPattern,
                                       const CFX_Matrix* pObject2Device,
                                       int width,
                                       int height,
                                       int flags) {
  CFX_DIBitmap* pBitmap = new CFX_DIBitmap;
  if (!pBitmap->Create(width, height,
                       pPattern->m_bColored ? FXDIB_Argb : FXDIB_8bppMask)) {
    delete pBitmap;
    return NULL;
  }
  CFX_FxgeDevice bitmap_device;
  bitmap_device.Attach(pBitmap);
  pBitmap->Clear(0);
  CFX_FloatRect cell_bbox = pPattern->m_BBox;
  pPattern->m_Pattern2Form.TransformRect(cell_bbox);
  pObject2Device->TransformRect(cell_bbox);
  CFX_FloatRect bitmap_rect(0.0f, 0.0f, (FX_FLOAT)width, (FX_FLOAT)height);
  CFX_Matrix mtAdjust;
  mtAdjust.MatchRect(bitmap_rect, cell_bbox);
  CFX_Matrix mtPattern2Bitmap = *pObject2Device;
  mtPattern2Bitmap.Concat(mtAdjust);
  CPDF_RenderOptions options;
  if (!pPattern->m_bColored) {
    options.m_ColorMode = RENDER_COLOR_ALPHA;
  }
  flags |= RENDER_FORCE_HALFTONE;
  options.m_Flags = flags;
  CPDF_RenderContext context(pDoc, pCache);
  context.DrawObjectList(&bitmap_device, pPattern->m_pForm, &mtPattern2Bitmap,
                         &options);
  return pBitmap;
}

//.........这里部分代码省略.........
  if (m_bPrint) {
    FX_BOOL bRet = FALSE;
    int rendCaps = m_pDevice->GetRenderCaps();
    if (!((Transparency & PDFTRANS_ISOLATED) || pSMaskDict || bTextClip) &&
        (rendCaps & FXRC_BLEND_MODE)) {
      int oldBlend = m_curBlend;
      m_curBlend = blend_type;
      bRet = DrawObjWithBlend(pPageObj, pObj2Device);
      m_curBlend = oldBlend;
    }
    if (!bRet) {
      DrawObjWithBackground(pPageObj, pObj2Device);
    }
    return TRUE;
  }
  FX_RECT rect = pPageObj->GetBBox(pObj2Device);
  rect.Intersect(m_pDevice->GetClipBox());
  if (rect.IsEmpty()) {
    return TRUE;
  }
  CFX_Matrix deviceCTM = m_pDevice->GetCTM();
  FX_FLOAT scaleX = FXSYS_fabs(deviceCTM.a);
  FX_FLOAT scaleY = FXSYS_fabs(deviceCTM.d);
  int width = FXSYS_round((FX_FLOAT)rect.Width() * scaleX);
  int height = FXSYS_round((FX_FLOAT)rect.Height() * scaleY);
  CFX_FxgeDevice bitmap_device;
  std::unique_ptr<CFX_DIBitmap> oriDevice;
  if (!isolated && (m_pDevice->GetRenderCaps() & FXRC_GET_BITS)) {
    oriDevice.reset(new CFX_DIBitmap);
    if (!m_pDevice->CreateCompatibleBitmap(oriDevice.get(), width, height))
      return TRUE;
    m_pDevice->GetDIBits(oriDevice.get(), rect.left, rect.top);
  }
  if (!bitmap_device.Create(width, height, FXDIB_Argb, oriDevice.get()))
    return TRUE;
  CFX_DIBitmap* bitmap = bitmap_device.GetBitmap();
  bitmap->Clear(0);
  CFX_Matrix new_matrix = *pObj2Device;
  new_matrix.TranslateI(-rect.left, -rect.top);
  new_matrix.Scale(scaleX, scaleY);
  std::unique_ptr<CFX_DIBitmap> pTextMask;
  if (bTextClip) {
    pTextMask.reset(new CFX_DIBitmap);
    if (!pTextMask->Create(width, height, FXDIB_8bppMask))
      return TRUE;

    pTextMask->Clear(0);
    CFX_FxgeDevice text_device;
    text_device.Attach(pTextMask.get(), false, nullptr, false);
    for (uint32_t i = 0; i < pPageObj->m_ClipPath.GetTextCount(); i++) {
      CPDF_TextObject* textobj = pPageObj->m_ClipPath.GetText(i);
      if (!textobj) {
        break;
      }
      CFX_Matrix text_matrix;
      textobj->GetTextMatrix(&text_matrix);
      CPDF_TextRenderer::DrawTextPath(
          &text_device, textobj->m_nChars, textobj->m_pCharCodes,
          textobj->m_pCharPos, textobj->m_TextState.GetFont(),
          textobj->m_TextState.GetFontSize(), &text_matrix, &new_matrix,
          textobj->m_GraphState.GetObject(), (FX_ARGB)-1, 0, nullptr, 0);
    }
  }
  CPDF_RenderStatus bitmap_render;
  bitmap_render.Initialize(m_pContext, &bitmap_device, nullptr, m_pStopObj,
                           nullptr, nullptr, &m_Options, 0, m_bDropObjects,
                           pFormResource, TRUE);
  bitmap_render.ProcessObjectNoClip(pPageObj, &new_matrix);
  m_bStopped = bitmap_render.m_bStopped;
  if (pSMaskDict) {
    CFX_Matrix smask_matrix = *pPageObj->m_GeneralState.GetSMaskMatrix();
    smask_matrix.Concat(*pObj2Device);
    std::unique_ptr<CFX_DIBSource> pSMaskSource(
        LoadSMask(pSMaskDict, &rect, &smask_matrix));
    if (pSMaskSource)
      bitmap->MultiplyAlpha(pSMaskSource.get());
  }
  if (pTextMask) {
    bitmap->MultiplyAlpha(pTextMask.get());
    pTextMask.reset();
  }
  int32_t blitAlpha = 255;
  if (Transparency & PDFTRANS_GROUP && group_alpha != 1.0f) {
    blitAlpha = (int32_t)(group_alpha * 255);
#ifndef _SKIA_SUPPORT_
    bitmap->MultiplyAlpha(blitAlpha);
    blitAlpha = 255;
#endif
  }
  Transparency = m_Transparency;
  if (pPageObj->IsForm()) {
    Transparency |= PDFTRANS_GROUP;
  }
  CompositeDIBitmap(bitmap, rect.left, rect.top, 0, blitAlpha, blend_type,
                    Transparency);
#if defined _SKIA_SUPPORT_
  DebugVerifyDeviceIsPreMultiplied();
#endif
  return TRUE;
}

FX_BOOL CPDF_RenderStatus::ProcessType3Text(const CPDF_TextObject* textobj, const CFX_AffineMatrix* pObj2Device)
{
    CPDF_Type3Font* pType3Font = textobj->m_TextState.GetFont()->GetType3Font();
    for (int j = 0; j < m_Type3FontCache.GetSize(); j++)
        if ((CPDF_Type3Font*)m_Type3FontCache.GetAt(j) == pType3Font) {
            return TRUE;
        }
    CFX_Matrix dCTM = m_pDevice->GetCTM();
    FX_FLOAT sa = FXSYS_fabs(dCTM.a);
    FX_FLOAT sd = FXSYS_fabs(dCTM.d);
    CFX_AffineMatrix text_matrix;
    textobj->GetTextMatrix(&text_matrix);
    CFX_AffineMatrix char_matrix = pType3Font->GetFontMatrix();
    FX_FLOAT font_size = textobj->m_TextState.GetFontSize();
    char_matrix.Scale(font_size, font_size);
    FX_ARGB fill_argb = GetFillArgb(textobj, TRUE);
    int fill_alpha = FXARGB_A(fill_argb);
    int device_class = m_pDevice->GetDeviceClass();
    FXTEXT_GLYPHPOS* pGlyphAndPos = NULL;
    if (device_class == FXDC_DISPLAY) {
        pGlyphAndPos = FX_Alloc(FXTEXT_GLYPHPOS, textobj->m_nChars);
    } else if (fill_alpha < 255) {
        return FALSE;
    }
    CPDF_RefType3Cache refTypeCache(pType3Font);
    FX_DWORD *pChars = textobj->m_pCharCodes;
    if (textobj->m_nChars == 1) {
        pChars = (FX_DWORD*)(&textobj->m_pCharCodes);
    }
    for (int iChar = 0; iChar < textobj->m_nChars; iChar ++) {
        FX_DWORD charcode = pChars[iChar];
        if (charcode == (FX_DWORD) - 1) {
            continue;
        }
        CPDF_Type3Char* pType3Char = pType3Font->LoadChar(charcode);
        if (pType3Char == NULL) {
            continue;
        }
        CFX_AffineMatrix matrix = char_matrix;
        matrix.e += iChar ? textobj->m_pCharPos[iChar - 1] : 0;
        matrix.Concat(text_matrix);
        matrix.Concat(*pObj2Device);
        if (!pType3Char->LoadBitmap(m_pContext)) {
            if (pGlyphAndPos) {
                for (int i = 0; i < iChar; i ++) {
                    FXTEXT_GLYPHPOS& glyph = pGlyphAndPos[i];
                    if (glyph.m_pGlyph == NULL) {
                        continue;
                    }
                    m_pDevice->SetBitMask(&glyph.m_pGlyph->m_Bitmap,
                                          glyph.m_OriginX + glyph.m_pGlyph->m_Left,
                                          glyph.m_OriginY - glyph.m_pGlyph->m_Top, fill_argb);
                }
                FX_Free(pGlyphAndPos);
                pGlyphAndPos = NULL;
            }
            CPDF_GraphicStates* pStates = CloneObjStates(textobj, FALSE);
            CPDF_RenderOptions Options = m_Options;
            Options.m_Flags |= RENDER_FORCE_HALFTONE | RENDER_RECT_AA;
            Options.m_Flags &= ~RENDER_FORCE_DOWNSAMPLE;
            CPDF_Dictionary* pFormResource = NULL;
            if (pType3Char->m_pForm && pType3Char->m_pForm->m_pFormDict) {
                pFormResource = pType3Char->m_pForm->m_pFormDict->GetDict(FX_BSTRC("Resources"));
            }
            if (fill_alpha == 255) {
                CPDF_RenderStatus status;
                status.Initialize(m_Level + 1, m_pContext, m_pDevice, NULL, NULL, this, pStates, &Options,
                                  pType3Char->m_pForm->m_Transparency, m_bDropObjects, pFormResource, FALSE, pType3Char, fill_argb);
                status.m_Type3FontCache.Append(m_Type3FontCache);
                status.m_Type3FontCache.Add(pType3Font);
                m_pDevice->SaveState();
                status.RenderObjectList(pType3Char->m_pForm, &matrix);
                m_pDevice->RestoreState();
            } else {
                CFX_FloatRect rect_f = pType3Char->m_pForm->CalcBoundingBox();
                rect_f.Transform(&matrix);
                FX_RECT rect = rect_f.GetOutterRect();
                CFX_FxgeDevice bitmap_device;
                if (!bitmap_device.Create((int)(rect.Width() * sa), (int)(rect.Height() * sd), FXDIB_Argb)) {
                    return TRUE;
                }
                bitmap_device.GetBitmap()->Clear(0);
                CPDF_RenderStatus status;
                status.Initialize(m_Level + 1, m_pContext, &bitmap_device, NULL, NULL, this, pStates, &Options,
                                  pType3Char->m_pForm->m_Transparency, m_bDropObjects, pFormResource, FALSE, pType3Char, fill_argb);
                status.m_Type3FontCache.Append(m_Type3FontCache);
                status.m_Type3FontCache.Add(pType3Font);
                matrix.TranslateI(-rect.left, -rect.top);
                matrix.Scale(sa, sd);
                status.RenderObjectList(pType3Char->m_pForm, &matrix);
                m_pDevice->SetDIBits(bitmap_device.GetBitmap(), rect.left, rect.top);
            }
            delete pStates;
        } else if (pType3Char->m_pBitmap) {
            if (device_class == FXDC_DISPLAY) {
                CPDF_Type3Cache* pCache = GetCachedType3(pType3Font);
                refTypeCache.m_dwCount++;
                CFX_GlyphBitmap* pBitmap = pCache->LoadGlyph(charcode, &matrix, sa, sd);
                if (pBitmap == NULL) {
                    continue;
//.........这里部分代码省略.........

FX_BOOL CFX_ImageTransformer::Continue(IFX_Pause* pPause)
{
    if (m_Status == 1) {
        if (m_Stretcher.Continue(pPause)) {
            return TRUE;
        }
        if (m_Storer.GetBitmap()) {
            m_Storer.Replace(m_Storer.GetBitmap()->SwapXY(m_pMatrix->c > 0, m_pMatrix->b < 0));
        }
        return FALSE;
    } else if (m_Status == 2) {
        return m_Stretcher.Continue(pPause);
    } else if (m_Status != 3) {
        return FALSE;
    }
    if (m_Stretcher.Continue(pPause)) {
        return TRUE;
    }
    int stretch_width = m_StretchClip.Width();
    int stretch_height = m_StretchClip.Height();
    if (m_Storer.GetBitmap() == NULL) {
        return FALSE;
    }
    FX_LPCBYTE stretch_buf = m_Storer.GetBitmap()->GetBuffer();
    FX_LPCBYTE stretch_buf_mask = NULL;
    if (m_Storer.GetBitmap()->m_pAlphaMask) {
        stretch_buf_mask = m_Storer.GetBitmap()->m_pAlphaMask->GetBuffer();
    }
    int stretch_pitch = m_Storer.GetBitmap()->GetPitch();
    CFX_DIBitmap* pTransformed = FX_NEW CFX_DIBitmap;
    if (!pTransformed) {
        return FALSE;
    }
    FXDIB_Format transformF = _GetTransformedFormat(m_Stretcher.m_pSource);
    if (!pTransformed->Create(m_ResultWidth, m_ResultHeight, transformF)) {
        delete pTransformed;
        return FALSE;
    }
    pTransformed->Clear(0);
    if (pTransformed->m_pAlphaMask) {
        pTransformed->m_pAlphaMask->Clear(0);
    }
    CFX_AffineMatrix result2stretch(1.0f, 0.0f, 0.0f, 1.0f, (FX_FLOAT)(m_ResultLeft), (FX_FLOAT)(m_ResultTop));
    result2stretch.Concat(m_dest2stretch);
    result2stretch.TranslateI(-m_StretchClip.left, -m_StretchClip.top);
    if (stretch_buf_mask == NULL && pTransformed->m_pAlphaMask) {
        pTransformed->m_pAlphaMask->Clear(0xff000000);
    } else if (pTransformed->m_pAlphaMask) {
        int stretch_pitch_mask = m_Storer.GetBitmap()->m_pAlphaMask->GetPitch();
        if (!(m_Flags & FXDIB_DOWNSAMPLE) && !(m_Flags & FXDIB_BICUBIC_INTERPOL)) {
            CFX_BilinearMatrix result2stretch_fix(result2stretch, 8);
            for (int row = 0; row < m_ResultHeight; row ++) {
                FX_BYTE* dest_pos_mask = (FX_BYTE*)pTransformed->m_pAlphaMask->GetScanline(row);
                for (int col = 0; col < m_ResultWidth; col ++) {
                    int src_col_l, src_row_l, res_x, res_y;
                    result2stretch_fix.Transform(col, row, src_col_l, src_row_l, res_x, res_y);
                    if (src_col_l >= 0 && src_col_l <= stretch_width && src_row_l >= 0 && src_row_l <= stretch_height) {
                        if (src_col_l == stretch_width) {
                            src_col_l--;
                        }
                        if (src_row_l == stretch_height) {
                            src_row_l--;
                        }
                        int src_col_r = src_col_l + 1;
                        int src_row_r = src_row_l + 1;
                        if (src_col_r == stretch_width) {
                            src_col_r--;
                        }
                        if (src_row_r == stretch_height) {
                            src_row_r--;
                        }
                        int row_offset_l = src_row_l * stretch_pitch_mask;
                        int row_offset_r = src_row_r * stretch_pitch_mask;
                        *dest_pos_mask = _bilinear_interpol(stretch_buf_mask, row_offset_l, row_offset_r, src_col_l, src_col_r, res_x, res_y, 1, 0);
                    }
                    dest_pos_mask++;
                }
            }
        } else if (m_Flags & FXDIB_BICUBIC_INTERPOL) {
            CFX_BilinearMatrix result2stretch_fix(result2stretch, 8);
            int pos_pixel[8];
            for (int row = 0; row < m_ResultHeight; row ++) {
                FX_BYTE* dest_pos_mask = (FX_BYTE*)pTransformed->m_pAlphaMask->GetScanline(row);
                for (int col = 0; col < m_ResultWidth; col ++) {
                    int src_col_l, src_row_l, res_x, res_y;
                    result2stretch_fix.Transform(col, row, src_col_l, src_row_l, res_x, res_y);
                    if (src_col_l >= 0 && src_col_l <= stretch_width && src_row_l >= 0 && src_row_l <= stretch_height) {
                        int u_w[4], v_w[4];
                        if (src_col_l == stretch_width) {
                            src_col_l--;
                        }
                        if (src_row_l == stretch_height) {
                            src_row_l--;
                        }
                        _bicubic_get_pos_weight(pos_pixel, u_w, v_w, src_col_l, src_row_l, res_x, res_y, stretch_width, stretch_height);
                        *dest_pos_mask = _bicubic_interpol(stretch_buf_mask, stretch_pitch_mask, pos_pixel, u_w, v_w, res_x, res_y, 1, 0);
                    }
                    dest_pos_mask++;
                }
            }
//.........这里部分代码省略.........

//.........这里部分代码省略.........
      blend_type == FXDIB_BLEND_NORMAL && !bTextClip && !bGroupTransparent) {
    return FALSE;
  }
  FX_BOOL isolated = Transparency & PDFTRANS_ISOLATED;
  if (m_bPrint) {
    FX_BOOL bRet = FALSE;
    int rendCaps = m_pDevice->GetRenderCaps();
    if (!((Transparency & PDFTRANS_ISOLATED) || pSMaskDict || bTextClip) &&
        (rendCaps & FXRC_BLEND_MODE)) {
      int oldBlend = m_curBlend;
      m_curBlend = blend_type;
      bRet = DrawObjWithBlend(pPageObj, pObj2Device);
      m_curBlend = oldBlend;
    }
    if (!bRet) {
      DrawObjWithBackground(pPageObj, pObj2Device);
    }
    return TRUE;
  }
  FX_RECT rect = pPageObj->GetBBox(pObj2Device);
  rect.Intersect(m_pDevice->GetClipBox());
  if (rect.IsEmpty()) {
    return TRUE;
  }
  CFX_Matrix deviceCTM = m_pDevice->GetCTM();
  FX_FLOAT scaleX = FXSYS_fabs(deviceCTM.a);
  FX_FLOAT scaleY = FXSYS_fabs(deviceCTM.d);
  int width = FXSYS_round((FX_FLOAT)rect.Width() * scaleX);
  int height = FXSYS_round((FX_FLOAT)rect.Height() * scaleY);
  CFX_FxgeDevice bitmap_device;
  nonstd::unique_ptr<CFX_DIBitmap> oriDevice;
  if (!isolated && (m_pDevice->GetRenderCaps() & FXRC_GET_BITS)) {
    oriDevice.reset(new CFX_DIBitmap);
    if (!m_pDevice->CreateCompatibleBitmap(oriDevice.get(), width, height))
      return TRUE;

    m_pDevice->GetDIBits(oriDevice.get(), rect.left, rect.top);
  }
  if (!bitmap_device.Create(width, height, FXDIB_Argb, 0, oriDevice.get()))
    return TRUE;

  CFX_DIBitmap* bitmap = bitmap_device.GetBitmap();
  bitmap->Clear(0);
  CFX_AffineMatrix new_matrix = *pObj2Device;
  new_matrix.TranslateI(-rect.left, -rect.top);
  new_matrix.Scale(scaleX, scaleY);
  nonstd::unique_ptr<CFX_DIBitmap> pTextMask;
  if (bTextClip) {
    pTextMask.reset(new CFX_DIBitmap);
    if (!pTextMask->Create(width, height, FXDIB_8bppMask))
      return TRUE;

    pTextMask->Clear(0);
    CFX_FxgeDevice text_device;
    text_device.Attach(pTextMask.get());
    for (FX_DWORD i = 0; i < pPageObj->m_ClipPath.GetTextCount(); i++) {
      CPDF_TextObject* textobj = pPageObj->m_ClipPath.GetText(i);
      if (textobj == NULL) {
        break;
      }
      CFX_AffineMatrix text_matrix;
      textobj->GetTextMatrix(&text_matrix);
      CPDF_TextRenderer::DrawTextPath(
          &text_device, textobj->m_nChars, textobj->m_pCharCodes,
          textobj->m_pCharPos, textobj->m_TextState.GetFont(),
          textobj->m_TextState.GetFontSize(), &text_matrix, &new_matrix,
          textobj->m_GraphState, (FX_ARGB)-1, 0, NULL);
    }
  }
  CPDF_RenderStatus bitmap_render;
  bitmap_render.Initialize(m_pContext, &bitmap_device, NULL, m_pStopObj, NULL,
                           NULL, &m_Options, 0, m_bDropObjects, pFormResource,
                           TRUE);
  bitmap_render.ProcessObjectNoClip(pPageObj, &new_matrix);
  m_bStopped = bitmap_render.m_bStopped;
  if (pSMaskDict) {
    CFX_AffineMatrix smask_matrix;
    FXSYS_memcpy(&smask_matrix, pGeneralState->m_SMaskMatrix,
                 sizeof smask_matrix);
    smask_matrix.Concat(*pObj2Device);
    nonstd::unique_ptr<CFX_DIBSource> pSMaskSource(
        LoadSMask(pSMaskDict, &rect, &smask_matrix));
    if (pSMaskSource)
      bitmap->MultiplyAlpha(pSMaskSource.get());
  }
  if (pTextMask) {
    bitmap->MultiplyAlpha(pTextMask.get());
    pTextMask.reset();
  }
  if (Transparency & PDFTRANS_GROUP && group_alpha != 1.0f) {
    bitmap->MultiplyAlpha((int32_t)(group_alpha * 255));
  }
  Transparency = m_Transparency;
  if (pPageObj->m_Type == PDFPAGE_FORM) {
    Transparency |= PDFTRANS_GROUP;
  }
  CompositeDIBitmap(bitmap, rect.left, rect.top, 0, 255, blend_type,
                    Transparency);
  return TRUE;
}

//.........这里部分代码省略.........
        status.RenderObjectList(pPattern->m_pForm, &matrix);
        m_pDevice->RestoreState();
      }
    m_pDevice->RestoreState();
    delete pStates;
    return;
  }
  if (bAligned) {
    int orig_x = FXSYS_round(mtPattern2Device.e);
    int orig_y = FXSYS_round(mtPattern2Device.f);
    min_col = (clip_box.left - orig_x) / width;
    if (clip_box.left < orig_x) {
      min_col--;
    }
    max_col = (clip_box.right - orig_x) / width;
    if (clip_box.right <= orig_x) {
      max_col--;
    }
    min_row = (clip_box.top - orig_y) / height;
    if (clip_box.top < orig_y) {
      min_row--;
    }
    max_row = (clip_box.bottom - orig_y) / height;
    if (clip_box.bottom <= orig_y) {
      max_row--;
    }
  }
  FX_FLOAT left_offset = cell_bbox.left - mtPattern2Device.e;
  FX_FLOAT top_offset = cell_bbox.bottom - mtPattern2Device.f;
  CFX_DIBitmap* pPatternBitmap = NULL;
  if (width * height < 16) {
    CFX_DIBitmap* pEnlargedBitmap =
        DrawPatternBitmap(m_pContext->m_pDocument, m_pContext->m_pPageCache,
                          pPattern, pObj2Device, 8, 8, m_Options.m_Flags);
    pPatternBitmap = pEnlargedBitmap->StretchTo(width, height);
    delete pEnlargedBitmap;
  } else {
    pPatternBitmap = DrawPatternBitmap(
        m_pContext->m_pDocument, m_pContext->m_pPageCache, pPattern,
        pObj2Device, width, height, m_Options.m_Flags);
  }
  if (!pPatternBitmap) {
    m_pDevice->RestoreState();
    return;
  }
  if (m_Options.m_ColorMode == RENDER_COLOR_GRAY) {
    pPatternBitmap->ConvertColorScale(m_Options.m_ForeColor,
                                      m_Options.m_BackColor);
  }
  FX_ARGB fill_argb = GetFillArgb(pPageObj);
  int clip_width = clip_box.right - clip_box.left;
  int clip_height = clip_box.bottom - clip_box.top;
  CFX_DIBitmap screen;
  if (!screen.Create(clip_width, clip_height, FXDIB_Argb)) {
    return;
  }
  screen.Clear(0);
  FX_DWORD* src_buf = (FX_DWORD*)pPatternBitmap->GetBuffer();
  for (int col = min_col; col <= max_col; col++) {
    for (int row = min_row; row <= max_row; row++) {
      int start_x, start_y;
      if (bAligned) {
        start_x = FXSYS_round(mtPattern2Device.e) + col * width - clip_box.left;
        start_y = FXSYS_round(mtPattern2Device.f) + row * height - clip_box.top;
      } else {
        FX_FLOAT orig_x = col * pPattern->m_XStep;
        FX_FLOAT orig_y = row * pPattern->m_YStep;
        mtPattern2Device.Transform(orig_x, orig_y);
        start_x = FXSYS_round(orig_x + left_offset) - clip_box.left;
        start_y = FXSYS_round(orig_y + top_offset) - clip_box.top;
      }
      if (width == 1 && height == 1) {
        if (start_x < 0 || start_x >= clip_box.Width() || start_y < 0 ||
            start_y >= clip_box.Height()) {
          continue;
        }
        FX_DWORD* dest_buf =
            (FX_DWORD*)(screen.GetBuffer() + screen.GetPitch() * start_y +
                        start_x * 4);
        if (pPattern->m_bColored) {
          *dest_buf = *src_buf;
        } else {
          *dest_buf = (*(uint8_t*)src_buf << 24) | (fill_argb & 0xffffff);
        }
      } else {
        if (pPattern->m_bColored) {
          screen.CompositeBitmap(start_x, start_y, width, height,
                                 pPatternBitmap, 0, 0);
        } else {
          screen.CompositeMask(start_x, start_y, width, height, pPatternBitmap,
                               fill_argb, 0, 0);
        }
      }
    }
  }
  CompositeDIBitmap(&screen, clip_box.left, clip_box.top, 0, 255,
                    FXDIB_BLEND_NORMAL, FALSE);
  m_pDevice->RestoreState();
  delete pPatternBitmap;
}

void CPDF_RenderStatus::DrawShading(CPDF_ShadingPattern* pPattern,
                                    CFX_Matrix* pMatrix,
                                    FX_RECT& clip_rect,
                                    int alpha,
                                    FX_BOOL bAlphaMode) {
  CPDF_Function** pFuncs = pPattern->m_pFunctions;
  int nFuncs = pPattern->m_nFuncs;
  CPDF_Dictionary* pDict = pPattern->m_pShadingObj->GetDict();
  CPDF_ColorSpace* pColorSpace = pPattern->m_pCS;
  if (!pColorSpace) {
    return;
  }
  FX_ARGB background = 0;
  if (!pPattern->m_bShadingObj &&
      pPattern->m_pShadingObj->GetDict()->KeyExist("Background")) {
    CPDF_Array* pBackColor =
        pPattern->m_pShadingObj->GetDict()->GetArray("Background");
    if (pBackColor &&
        pBackColor->GetCount() >= (FX_DWORD)pColorSpace->CountComponents()) {
      CFX_FixedBufGrow<FX_FLOAT, 16> comps(pColorSpace->CountComponents());
      for (int i = 0; i < pColorSpace->CountComponents(); i++) {
        comps[i] = pBackColor->GetNumber(i);
      }
      FX_FLOAT R = 0.0f, G = 0.0f, B = 0.0f;
      pColorSpace->GetRGB(comps, R, G, B);
      background = ArgbEncode(255, (int32_t)(R * 255), (int32_t)(G * 255),
                              (int32_t)(B * 255));
    }
  }
  if (pDict->KeyExist("BBox")) {
    CFX_FloatRect rect = pDict->GetRect("BBox");
    rect.Transform(pMatrix);
    clip_rect.Intersect(rect.GetOutterRect());
  }
  CPDF_DeviceBuffer buffer;
  buffer.Initialize(m_pContext, m_pDevice, &clip_rect, m_pCurObj, 150);
  CFX_Matrix FinalMatrix = *pMatrix;
  FinalMatrix.Concat(*buffer.GetMatrix());
  CFX_DIBitmap* pBitmap = buffer.GetBitmap();
  if (!pBitmap->GetBuffer()) {
    return;
  }
  pBitmap->Clear(background);
  int fill_mode = m_Options.m_Flags;
  switch (pPattern->m_ShadingType) {
    case kInvalidShading:
    case kMaxShading:
      return;
    case kFunctionBasedShading:
      DrawFuncShading(pBitmap, &FinalMatrix, pDict, pFuncs, nFuncs, pColorSpace,
                      alpha);
      break;
    case kAxialShading:
      DrawAxialShading(pBitmap, &FinalMatrix, pDict, pFuncs, nFuncs,
                       pColorSpace, alpha);
      break;
    case kRadialShading:
      DrawRadialShading(pBitmap, &FinalMatrix, pDict, pFuncs, nFuncs,
                        pColorSpace, alpha);
      break;
    case kFreeFormGouraudTriangleMeshShading: {
      DrawFreeGouraudShading(pBitmap, &FinalMatrix,
                             ToStream(pPattern->m_pShadingObj), pFuncs, nFuncs,
                             pColorSpace, alpha);
    } break;
    case kLatticeFormGouraudTriangleMeshShading: {
      DrawLatticeGouraudShading(pBitmap, &FinalMatrix,
                                ToStream(pPattern->m_pShadingObj), pFuncs,
                                nFuncs, pColorSpace, alpha);
    } break;
    case kCoonsPatchMeshShading:
    case kTensorProductPatchMeshShading: {
      DrawCoonPatchMeshes(
          pPattern->m_ShadingType == kTensorProductPatchMeshShading, pBitmap,
          &FinalMatrix, ToStream(pPattern->m_pShadingObj), pFuncs, nFuncs,
          pColorSpace, fill_mode, alpha);
    } break;
  }
  if (bAlphaMode) {
    pBitmap->LoadChannel(FXDIB_Red, pBitmap, FXDIB_Alpha);
  }
  if (m_Options.m_ColorMode == RENDER_COLOR_GRAY) {
    pBitmap->ConvertColorScale(m_Options.m_ForeColor, m_Options.m_BackColor);
  }
  buffer.OutputToDevice();
}

DLLEXPORT void STDCALL FPDF_RenderPage(HDC dc, FPDF_PAGE page, int start_x, int start_y, int size_x, int size_y,
                                       int rotate, int flags)
{
    if (page==NULL) return;
    CPDF_Page* pPage = (CPDF_Page*)page;

    CRenderContext* pContext = FX_NEW CRenderContext;
    pPage->SetPrivateData((void*)1, pContext, DropContext);

#ifndef _WIN32_WCE
    CFX_DIBitmap* pBitmap = NULL;
    FX_BOOL bBackgroundAlphaNeeded=FALSE;
    bBackgroundAlphaNeeded = pPage->BackgroundAlphaNeeded();
    if (bBackgroundAlphaNeeded)
    {

        pBitmap = FX_NEW CFX_DIBitmap;
        pBitmap->Create(size_x, size_y, FXDIB_Argb);
        pBitmap->Clear(0x00ffffff);
#ifdef _SKIA_SUPPORT_
        pContext->m_pDevice = FX_NEW CFX_SkiaDevice;
        ((CFX_SkiaDevice*)pContext->m_pDevice)->Attach((CFX_DIBitmap*)pBitmap);
#else
        pContext->m_pDevice = FX_NEW CFX_FxgeDevice;
        ((CFX_FxgeDevice*)pContext->m_pDevice)->Attach((CFX_DIBitmap*)pBitmap);
#endif
    }
    else
        pContext->m_pDevice = FX_NEW CFX_WindowsDevice(dc);
    if (flags & FPDF_NO_CATCH)
        Func_RenderPage(pContext, page, start_x, start_y, size_x, size_y, rotate, flags,TRUE,NULL);
    else {
        try {
            Func_RenderPage(pContext, page, start_x, start_y, size_x, size_y, rotate, flags,TRUE,NULL);
        } catch (...) {
        }
    }
    if (bBackgroundAlphaNeeded)
    {
        if (pBitmap)
        {
            CFX_WindowsDevice WinDC(dc);

            if (WinDC.GetDeviceCaps(FXDC_DEVICE_CLASS) == FXDC_PRINTER)
            {
                CFX_DIBitmap* pDst = FX_NEW CFX_DIBitmap;
                pDst->Create(pBitmap->GetWidth(), pBitmap->GetHeight(),FXDIB_Rgb32);
                FXSYS_memcpy(pDst->GetBuffer(), pBitmap->GetBuffer(), pBitmap->GetPitch()*pBitmap->GetHeight());
//				WinDC.SetDIBits(pDst,0,0);
                WinDC.StretchDIBits(pDst,0,0,size_x*2,size_y*2);
                delete pDst;
            }
            else
                WinDC.SetDIBits(pBitmap,0,0);

        }
    }
#else
    // get clip region
    RECT rect, cliprect;
    rect.left = start_x;
    rect.top = start_y;
    rect.right = start_x + size_x;
    rect.bottom = start_y + size_y;
    GetClipBox(dc, &cliprect);
    IntersectRect(&rect, &rect, &cliprect);
    int width = rect.right - rect.left;
    int height = rect.bottom - rect.top;

#ifdef DEBUG_TRACE
    {
        char str[128];
        sprintf(str, "Rendering DIB %d x %d", width, height);
        CPDF_ModuleMgr::Get()->ReportError(999, str);
    }
#endif

    // Create a DIB section
    LPVOID pBuffer;
    BITMAPINFOHEADER bmih;
    FXSYS_memset(&bmih, 0, sizeof bmih);
    bmih.biSize = sizeof bmih;
    bmih.biBitCount = 24;
    bmih.biHeight = -height;
    bmih.biPlanes = 1;
    bmih.biWidth = width;
    pContext->m_hBitmap = CreateDIBSection(dc, (BITMAPINFO*)&bmih, DIB_RGB_COLORS, &pBuffer, NULL, 0);
    if (pContext->m_hBitmap == NULL) {
#if defined(DEBUG) || defined(_DEBUG)
        char str[128];
        sprintf(str, "Error CreateDIBSection: %d x %d, error code = %d", width, height, GetLastError());
        CPDF_ModuleMgr::Get()->ReportError(FPDFERR_OUT_OF_MEMORY, str);
#else
        CPDF_ModuleMgr::Get()->ReportError(FPDFERR_OUT_OF_MEMORY, NULL);
#endif
    }
    FXSYS_memset(pBuffer, 0xff, height*((width*3+3)/4*4));

#ifdef DEBUG_TRACE
    {
//.........这里部分代码省略.........