style(代码风格): 整理声明顺序与字体模块

ofdgo_render_output.go

@@ -87,30 +87,6 @@ func (r *Renderer) RenderTo(page *PageContent, writer io.Writer, format string)
 	return render(page, writer)
 }
 
-// outputRenderer 获取格式扩展名和渲染方法
-// 入参: format 输出格式
-// 返回: string 扩展名, func 渲染方法, error 错误信息
-func (r *Renderer) outputRenderer(format string) (string, func(*PageContent, io.Writer) error, error) {
-	switch strings.ToLower(strings.TrimSpace(format)) {
-	case "svg":
-		return "svg", r.RenderToSVG, nil
-	case "pdf":
-		return "pdf", r.RenderToPDF, nil
-	case "txt":
-		return "txt", r.RenderToText, nil
-	case "eps":
-		return "eps", r.RenderToEPS, nil
-	case "png":
-		return "png", r.RenderToPNG, nil
-	case "jpg", "jpeg":
-		return "jpg", func(page *PageContent, writer io.Writer) error {
-			return r.RenderToJPEG(page, writer, &jpeg.Options{Quality: 95})
-		}, nil
-	default:
-		return "", nil, fmt.Errorf("unsupported output format %s", format)
-	}
-}
-
 // RenderToZIP 逐页渲染并写入ZIP，文件编号按总页数补零，出错时调用方应丢弃输出
 // 入参: writer 输出流, format svg、pdf、eps、png、jpg、jpeg或txt, indices 零基页面索引，省略则全部，按原页序去重
 // 返回: error 错误信息
@@ -203,16 +179,6 @@ func (r *Renderer) RenderToMultiPageText(writer io.Writer, indices ...int) error
 	return nil
 }
 
-// exportProgress 回报导出进度并传递调用方的停止原因
-// 入参: completed 已处理页数, total 总页数
-// 返回: error 停止原因
-func (r *Renderer) exportProgress(completed, total int) error {
-	if r.OnExportProgress != nil {
-		return r.OnExportProgress(completed, total)
-	}
-	return nil
-}
-
 // RenderToImage 渲染为光栅图
 // 入参: page 页面内容
 // 返回: image.Image 图像对象, error 错误信息
@@ -257,31 +223,6 @@ func (r *Renderer) RenderToJPEG(page *PageContent, writer io.Writer, options *jp
 	return jpeg.Encode(&imageMetadataWriter{writer: writer, skip: 2, data: segment}, fillWhiteBackground(img), options)
 }
 
-// fillWhiteBackground 填充白色背景，复用当前导出图片的RGBA像素
-// 入参: img 图片对象
-// 返回: image.Image 图片对象
-func fillWhiteBackground(img image.Image) image.Image {
-	bounds := img.Bounds()
-	if rgba, ok := img.(*image.RGBA); ok {
-		for y := 0; y < bounds.Dy(); y++ {
-			row := rgba.Pix[y*rgba.Stride : y*rgba.Stride+bounds.Dx()*4]
-			for i := 0; i < len(row); i += 4 {
-				if alpha := 255 - row[i+3]; alpha != 0 {
-					row[i] += alpha
-					row[i+1] += alpha
-					row[i+2] += alpha
-					row[i+3] = 255
-				}
-			}
-		}
-		return rgba
-	}
-	dst := image.NewRGBA(bounds)
-	draw.Draw(dst, bounds, image.White, image.Point{}, draw.Src)
-	draw.Draw(dst, bounds, img, bounds.Min, draw.Over)
-	return dst
-}
-
 // RenderToSVG 渲染为SVG
 // 入参: page 页面内容, writer 输出流
 // 返回: error 错误信息
@@ -363,6 +304,65 @@ func (r *Renderer) RenderPagesToPDF(contents []*PageContent, writer io.Writer) e
 	return r.renderPDFPages(pages, writer, r.OnExportProgress)
 }
 
+// outputRenderer 获取格式扩展名和渲染方法
+// 入参: format 输出格式
+// 返回: string 扩展名, func 渲染方法, error 错误信息
+func (r *Renderer) outputRenderer(format string) (string, func(*PageContent, io.Writer) error, error) {
+	switch strings.ToLower(strings.TrimSpace(format)) {
+	case "svg":
+		return "svg", r.RenderToSVG, nil
+	case "pdf":
+		return "pdf", r.RenderToPDF, nil
+	case "txt":
+		return "txt", r.RenderToText, nil
+	case "eps":
+		return "eps", r.RenderToEPS, nil
+	case "png":
+		return "png", r.RenderToPNG, nil
+	case "jpg", "jpeg":
+		return "jpg", func(page *PageContent, writer io.Writer) error {
+			return r.RenderToJPEG(page, writer, &jpeg.Options{Quality: 95})
+		}, nil
+	default:
+		return "", nil, fmt.Errorf("unsupported output format %s", format)
+	}
+}
+
+// exportProgress 回报导出进度并传递调用方的停止原因
+// 入参: completed 已处理页数, total 总页数
+// 返回: error 停止原因
+func (r *Renderer) exportProgress(completed, total int) error {
+	if r.OnExportProgress != nil {
+		return r.OnExportProgress(completed, total)
+	}
+	return nil
+}
+
+// fillWhiteBackground 填充白色背景，复用当前导出图片的RGBA像素
+// 入参: img 图片对象
+// 返回: image.Image 图片对象
+func fillWhiteBackground(img image.Image) image.Image {
+	bounds := img.Bounds()
+	if rgba, ok := img.(*image.RGBA); ok {
+		for y := 0; y < bounds.Dy(); y++ {
+			row := rgba.Pix[y*rgba.Stride : y*rgba.Stride+bounds.Dx()*4]
+			for i := 0; i < len(row); i += 4 {
+				if alpha := 255 - row[i+3]; alpha != 0 {
+					row[i] += alpha
+					row[i+1] += alpha
+					row[i+2] += alpha
+					row[i+3] = 255
+				}
+			}
+		}
+		return rgba
+	}
+	dst := image.NewRGBA(bounds)
+	draw.Draw(dst, bounds, image.White, image.Point{}, draw.Src)
+	draw.Draw(dst, bounds, img, bounds.Min, draw.Over)
+	return dst
+}
+
 // renderPDFPages 将已解析页面交给指定PDF后端
 // 入参: pages 页面列表, writer 输出流, progress 页面处理进度
 // 返回: error 错误信息