Files
ofdgo/ofdgo_renderer_layer.go
T
xiaoqidun 6aa4e99530
build.yaml / build (push) Successful in 34s
feat(渲染优化): 完善渲染逻辑
2026-07-16 11:15:29 +08:00

255 lines
9.2 KiB
Go

// Copyright 2025-2026 肖其顿 (XIAO QI DUN)
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package ofdgo
import (
"image/color"
"github.com/tdewolff/canvas"
)
// renderAnnotations 渲染页面注释外观
// 入参: ctx 画布上下文, pageID 页面ID, pageH 页面高度
func (r *Renderer) renderAnnotations(ctx *canvas.Context, pageID string, pageH float64) {
for _, annot := range r.Reader.Annots[pageID] {
if len(annot.Appearance.Objects) == 0 {
continue
}
box, _ := ParseBox(annot.Appearance.Boundary)
ctm := Matrix{a: 1, d: 1, e: box.X, f: box.Y}
for _, obj := range annot.Appearance.Objects {
r.renderObject(ctx, obj, pageH, nil, nil, 0, &ctm, false, nil)
}
}
}
// renderTemplate 渲染模板
// 入参: ctx 画布上下文, templateID 模板ID, pageH 页面高度
func (r *Renderer) renderTemplate(ctx *canvas.Context, templateID string, pageH float64) {
tplContent := r.templatePageCache[templateID]
if tplContent == nil {
var tplPage *TemplatePage
for i := range r.Reader.doc.CommonData.TemplatePage {
if r.Reader.doc.CommonData.TemplatePage[i].ID == templateID {
tplPage = &r.Reader.doc.CommonData.TemplatePage[i]
break
}
}
if tplPage == nil {
return
}
var err error
tplContent, err = r.Reader.PageContent(Page{BaseLoc: tplPage.BaseLoc})
if err != nil {
return
}
r.templatePageCache[templateID] = tplContent
}
if tplContent.Content.Layer != nil {
for _, layer := range tplContent.Content.Layer {
r.renderLayer(ctx, layer, pageH, nil, nil, 0, nil)
}
}
}
// renderLayer 渲染图层
// 入参: ctx 画布上下文, layer 图层对象, pageH 页面高度, defaultFill 默认填充色, defaultStroke 默认描边色, defaultLW 默认线宽, parentCTM 父级CTM
func (r *Renderer) renderLayer(ctx *canvas.Context, layer Layer, pageH float64, defaultFill, defaultStroke color.Color, defaultLW float64, parentCTM *Matrix) {
defaultFill, defaultStroke, defaultLW = r.drawParamDefaults(layer.DrawParam, defaultFill, defaultStroke, defaultLW)
if len(layer.Objects) > 0 {
for _, obj := range layer.Objects {
r.renderObject(ctx, obj, pageH, defaultFill, defaultStroke, defaultLW, parentCTM, false, nil)
}
return
}
for _, textObj := range layer.TextObject {
r.renderText(ctx, textObj, pageH, defaultFill, defaultStroke, parentCTM, false, nil)
}
for _, pathObj := range layer.PathObject {
r.renderPath(ctx, pathObj, pageH, defaultFill, defaultStroke, defaultLW, parentCTM, false, nil)
}
for _, imgObj := range layer.ImageObject {
r.renderImage(ctx, imgObj, pageH, parentCTM, false, nil)
}
for _, cgu := range layer.CompositeGraphicUnit {
r.renderCompositeGraphicUnit(ctx, cgu, pageH, defaultFill, defaultStroke, defaultLW, parentCTM, false, nil)
}
}
// renderCompositeGraphicUnit 渲染复合图元
// 入参: ctx 画布上下文, cgu 复合图元对象, pageH 页面高度, defaultFill 默认填充色, defaultStroke 默认描边色, defaultLW 默认线宽, parentCTM 父级CTM, boundaryInCTM 边界是否参与CTM变换, parentClip 父级裁剪路径
func (r *Renderer) renderCompositeGraphicUnit(ctx *canvas.Context, cgu CompositeGraphicUnit, pageH float64, defaultFill, defaultStroke color.Color, defaultLW float64, parentCTM *Matrix, boundaryInCTM bool, parentClip *canvas.Path) {
if cgu.Visible != nil && !*cgu.Visible {
return
}
ctx.Push()
currentCTM := NewMatrix(cgu.CTM)
if parentCTM != nil {
currentCTM = parentCTM.Multiply(currentCTM)
}
box, _ := ParseBox(cgu.Boundary)
clipPath := intersectClipPath(parentClip, r.buildClipPath(cgu.Clips, pageH, box.X, box.Y, currentCTM))
if cgu.ResourceID != "" {
if ref, ok := r.CompositeGraphicUnits[cgu.ResourceID]; ok {
refCopy := *ref
refCopy.Alpha = mergeAlpha(refCopy.Alpha, cgu.Alpha)
r.renderCompositeGraphicUnit(ctx, refCopy, pageH, defaultFill, defaultStroke, defaultLW, &currentCTM, true, clipPath)
}
}
defaultFill, defaultStroke, defaultLW = r.drawParamDefaults(cgu.DrawParam, defaultFill, defaultStroke, defaultLW)
if len(cgu.Objects) > 0 {
for _, obj := range cgu.Objects {
obj = mergeGraphicObjectAlpha(obj, cgu.Alpha)
r.renderObject(ctx, obj, pageH, defaultFill, defaultStroke, defaultLW, &currentCTM, boundaryInCTM, clipPath)
}
ctx.Pop()
return
}
for _, imgObj := range cgu.ImageObject {
imgObj.Alpha = mergeAlpha(imgObj.Alpha, cgu.Alpha)
r.renderImage(ctx, imgObj, pageH, &currentCTM, boundaryInCTM, clipPath)
}
for _, pathObj := range cgu.PathObject {
pathObj.Alpha = mergeAlpha(pathObj.Alpha, cgu.Alpha)
r.renderPath(ctx, pathObj, pageH, defaultFill, defaultStroke, defaultLW, &currentCTM, boundaryInCTM, clipPath)
}
for _, textObj := range cgu.TextObject {
textObj.Alpha = mergeAlpha(textObj.Alpha, cgu.Alpha)
r.renderText(ctx, textObj, pageH, defaultFill, defaultStroke, &currentCTM, boundaryInCTM, clipPath)
}
for _, subCgu := range cgu.CompositeGraphicUnit {
subCgu.Alpha = mergeAlpha(subCgu.Alpha, cgu.Alpha)
r.renderCompositeGraphicUnit(ctx, subCgu, pageH, defaultFill, defaultStroke, defaultLW, &currentCTM, boundaryInCTM, clipPath)
}
ctx.Pop()
}
// renderObject 渲染图形对象
// 入参: ctx 画布上下文, obj 图形对象, pageH 页面高度, defaultFill 默认填充色, defaultStroke 默认描边色, defaultLW 默认线宽, parentCTM 父级CTM, boundaryInCTM 边界是否参与CTM变换, parentClip 父级裁剪路径
func (r *Renderer) renderObject(ctx *canvas.Context, obj GraphicObject, pageH float64, defaultFill, defaultStroke color.Color, defaultLW float64, parentCTM *Matrix, boundaryInCTM bool, parentClip *canvas.Path) {
switch obj.Type {
case "TextObject":
r.renderText(ctx, obj.TextObject, pageH, defaultFill, defaultStroke, parentCTM, boundaryInCTM, parentClip)
case "PathObject":
r.renderPath(ctx, obj.PathObject, pageH, defaultFill, defaultStroke, defaultLW, parentCTM, boundaryInCTM, parentClip)
case "ImageObject":
r.renderImage(ctx, obj.ImageObject, pageH, parentCTM, boundaryInCTM, parentClip)
case "CompositeGraphicUnit", "CompositeObject":
r.renderCompositeGraphicUnit(ctx, obj.CompositeGraphicUnit, pageH, defaultFill, defaultStroke, defaultLW, parentCTM, boundaryInCTM, parentClip)
}
}
// mergeGraphicObjectAlpha 合并图形对象透明度
// 入参: obj 图形对象, alpha 父级透明度
// 返回: GraphicObject 合并后的图形对象
func mergeGraphicObjectAlpha(obj GraphicObject, alpha *int) GraphicObject {
if alpha == nil {
return obj
}
switch obj.Type {
case "TextObject":
obj.TextObject.Alpha = mergeAlpha(obj.TextObject.Alpha, alpha)
case "PathObject":
obj.PathObject.Alpha = mergeAlpha(obj.PathObject.Alpha, alpha)
case "ImageObject":
obj.ImageObject.Alpha = mergeAlpha(obj.ImageObject.Alpha, alpha)
case "CompositeGraphicUnit", "CompositeObject":
obj.CompositeGraphicUnit.Alpha = mergeAlpha(obj.CompositeGraphicUnit.Alpha, alpha)
}
return obj
}
// drawParamDefaults 合并绘制参数默认样式
// 入参: id 绘制参数ID, defaultFill 默认填充色, defaultStroke 默认描边色, defaultLW 默认线宽
// 返回: color.Color 默认填充色, color.Color 默认描边色, float64 默认线宽
func (r *Renderer) drawParamDefaults(id string, defaultFill, defaultStroke color.Color, defaultLW float64) (color.Color, color.Color, float64) {
if id == "" {
return defaultFill, defaultStroke, defaultLW
}
dp := r.getDrawParam(id, nil)
if dp == nil {
return defaultFill, defaultStroke, defaultLW
}
if dp.LineWidth > 0 {
defaultLW = dp.LineWidth
}
if dp.FillColor != nil {
defaultFill = parseFillColor(dp.FillColor)
}
if dp.StrokeColor != nil {
defaultStroke = parseStrokeColor(dp.StrokeColor)
}
return defaultFill, defaultStroke, defaultLW
}
// getDrawParam 获取绘制参数逻辑
// 入参: id 参数ID, visited 访问记录
// 返回: *DrawParam 绘制参数
func (r *Renderer) getDrawParam(id string, visited map[string]bool) *DrawParam {
if visited == nil {
visited = make(map[string]bool)
}
if visited[id] {
return nil
}
visited[id] = true
if dp, ok := r.DrawParams[id]; ok {
if dp.Relative != "" {
base := r.getDrawParam(dp.Relative, visited)
if base == nil {
return dp
}
merged := *base
if dp.LineWidth > 0 {
merged.LineWidth = dp.LineWidth
}
if dp.Join != "" {
merged.Join = dp.Join
}
if dp.Cap != "" {
merged.Cap = dp.Cap
}
if dp.DashPattern != "" {
merged.DashPattern = dp.DashPattern
merged.DashOffset = dp.DashOffset
}
if dp.MiterLimit > 0 {
merged.MiterLimit = dp.MiterLimit
}
if dp.FillColor != nil {
merged.FillColor = dp.FillColor
}
if dp.StrokeColor != nil {
merged.StrokeColor = dp.StrokeColor
}
if dp.Font != "" {
merged.Font = dp.Font
}
if dp.Size > 0 {
merged.Size = dp.Size
}
if dp.Weight > 0 {
merged.Weight = dp.Weight
}
if dp.Italic {
merged.Italic = dp.Italic
}
return &merged
}
return dp
}
return nil
}