Files
ofdgo/ofdgo_render_pattern.go
T
2026-09-23 21:05:47 +08:00

235 lines
8.2 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 (
"crypto/sha256"
"slices"
)
// stampContentKey 区分印章内容、物理尺寸、裁剪与字体栅格化精度,不含放置位置
type stampContentKey struct {
data [32]byte
kind string
width, height float64
dpi float64
clip Box
clipped bool
annotations bool
}
// stampContentState 保存有界的共享签章编译结果及配置
type stampContentState struct {
config RenderBackends
cache renderCache[stampContentKey, []RasterCommand]
}
// stampContentStateKey 隔离渲染器私有的共享签章数据
type stampContentStateKey struct{}
// resetFonts 使包含文字的签章编译结果随字体配置失效
func (s *stampContentState) resetFonts() {
s.cache = renderCache[stampContentKey, []RasterCommand]{limit: 16 << 20}
}
// sharedStamp 复用相同签章的解码、嵌套文档编译及局部裁剪,不缓存放置位置
// 入参: stamp 签章, compile 未缓存的签章编译方法
// 返回: error 签章解析或编译错误
func (c *semanticCompiler) sharedStamp(stamp Stamp, compile func(*semanticCompiler, Stamp) error) error {
if c.textOnly || c.measure || len(stamp.Data) == 0 {
return nil
}
r := c.renderer
state, _ := r.backendStates[stampContentStateKey{}].(*stampContentState)
config := r.backends
if state == nil || !sameBackend(state.config.Fonts, config.Fonts) || !sameBackend(state.config.Geometry, config.Geometry) ||
!sameBackend(state.config.Compiler, config.Compiler) || !sameBackend(state.config.Raster, config.Raster) {
state = &stampContentState{config: config}
state.resetFonts()
r.backendStates[stampContentStateKey{}] = state
}
key := stampContentKey{data: sha256.Sum256(stamp.Data), kind: stamp.Type, width: stamp.Box.W, height: stamp.Box.H, dpi: c.page.DPI, clipped: stamp.Clip != nil, annotations: r.RenderAnnotations}
if stamp.Clip != nil {
key.clip = *stamp.Clip
}
commands, ok := state.cache.get(key)
if !ok {
local := stamp
local.Box.X, local.Box.Y = 0, 0
page := &RasterPage{Width: c.page.Width, Height: c.page.Height, DPI: c.page.DPI}
child := &semanticCompiler{renderer: r, geometry: c.geometry, page: page, patterns: c.patterns}
if err := compile(child, local); err != nil {
return err
}
commands = page.Commands
cost := 0
for _, command := range commands {
cost += rasterCommandCost(command)
if command.Image != nil {
bounds := command.Image.Bounds()
cost += bounds.Dx() * bounds.Dy() * 4
}
}
state.cache.put(key, commands, cost)
}
c.page.Commands = append(c.page.Commands, translatePatternCommands(commands, stamp.Box.X, stamp.Box.Y)...)
return nil
}
// patternCellKey 区分共享底纹、颜色、透明度和影响单元语义的页面变换
type patternCellKey struct {
pattern *Pattern
color, space string
index, alpha int
colorAlpha int
matrix [6]float64
}
// patternCell 复用同次编译中相同底纹单元,不缓存外部对象的裁剪
// 入参: pattern 底纹画刷, matrix 单元到页面矩阵
// 返回: []RasterCommand 只读单元指令, error 编译错误
func (c *semanticCompiler) patternCell(pattern *PatternPaint, matrix Matrix) ([]RasterCommand, error) {
x, y := 0.0, 0.0
if patternCellTranslatable(pattern) {
x, y = matrix.e, matrix.f
matrix.e, matrix.f = 0, 0
}
key := patternCellKey{pattern: pattern.Pattern, color: pattern.Color.Value, space: pattern.Color.ColorSpace, index: -1, alpha: 255, colorAlpha: 255, matrix: matrix.Values()}
if pattern.Color.Index != nil {
key.index = *pattern.Color.Index
}
if pattern.Alpha != nil {
key.alpha = *pattern.Alpha
}
if pattern.Color.Alpha != nil {
key.colorAlpha = *pattern.Color.Alpha
}
if commands, ok := c.patterns.get(key); ok {
return translatePatternCommands(commands, x, y), nil
}
child := &semanticCompiler{renderer: c.renderer, geometry: c.geometry, page: &RasterPage{Width: c.page.Width, Height: c.page.Height, DPI: c.page.DPI}, pattern: true, patterns: c.patterns}
defaults := &DrawParam{FillColor: &pattern.Color, StrokeColor: (*StrokeColor)(&pattern.Color)}
for _, object := range pattern.CellContent.Objects {
object = mergeGraphicObjectAlpha(object, pattern.Alpha)
if err := c.renderer.WalkObject(&object, RenderState{Defaults: defaults, Parent: &matrix, BoundaryInCTM: true}, child); err != nil {
return nil, err
}
}
cost := 0
for _, cmd := range child.page.Commands {
cost += rasterCommandCost(cmd)
}
c.patterns.put(key, child.page.Commands, cost)
return translatePatternCommands(child.page.Commands, x, y), nil
}
// patternCellTranslatable 检查无需按页面位置重新解释的叶子单元
// 入参: pattern 底纹画刷
// 返回: bool 是否可仅平移编译结果
func patternCellTranslatable(pattern *PatternPaint) bool {
if pattern.Color.Pattern != nil {
return false
}
for _, object := range pattern.CellContent.Objects {
var fill, stroke *FillColor
switch object.Type {
case "PathObject":
if object.PathObject.DrawParam != "" {
return false
}
fill, stroke = object.PathObject.FillColor, (*FillColor)(object.PathObject.StrokeColor)
case "TextObject":
if object.TextObject.DrawParam != "" {
return false
}
fill, stroke = object.TextObject.FillColor, (*FillColor)(object.TextObject.StrokeColor)
case "ImageObject":
if object.ImageObject.Border != nil {
stroke = (*FillColor)(object.ImageObject.Border.BorderColor)
}
default:
return false
}
if fill != nil && fill.Pattern != nil || stroke != nil && stroke.Pattern != nil {
return false
}
}
return true
}
// translatePatternCommands 平移单元实例,共享只读路径和画刷,独立处理页面裁剪
// 入参: commands 原点单元, x 横向平移, y 纵向平移
// 返回: []RasterCommand 放置后的指令
func translatePatternCommands(commands []RasterCommand, x, y float64) []RasterCommand {
if x == 0 && y == 0 {
return commands
}
result := slices.Clone(commands)
for i := range result {
command := &result[i]
command.Transform[4] += x
command.Transform[5] += y
if command.Clip != nil {
command.Clip = slices.Clone(command.Clip)
matrix := RasterMatrix{1, 0, 0, 1, x, y}
for j := range command.Clip {
segment := &command.Clip[j]
segment.End = matrix.Apply(segment.End)
segment.Control1 = matrix.Apply(segment.Control1)
segment.Control2 = matrix.Apply(segment.Control2)
}
}
}
return result
}
// appendPatternCell 将缓存指令放入当前裁剪,不修改单元数据
// 入参: commands 单元指令, clip 页面裁剪, segments 已转换裁剪
// 返回: error 裁剪合并错误
func (c *semanticCompiler) appendPatternCell(commands []RasterCommand, clip GeometryPath, segments []RasterSegment) error {
for _, command := range commands {
commandClip := segments
if command.Clip != nil {
path := geometryFromRaster(command.Clip)
combined, err := c.geometry.Combine(path, clip, GeometryIntersect)
if err != nil {
return err
}
commandClip, err = c.segments(combined)
if err != nil {
return err
}
}
command.Clip = commandClip
c.page.Commands = append(c.page.Commands, command)
}
return nil
}
// geometryFromRaster 将只含贝塞尔曲线的光栅路径还原为库路径
// 入参: path 光栅路径
// 返回: GeometryPath 库路径
func geometryFromRaster(path []RasterSegment) GeometryPath {
result := make(GeometryPath, 0, len(path))
for _, s := range path {
verb := GeometryVerb(s.Verb)
if s.Verb == RasterClose {
verb = GeometryClose
}
result = append(result, GeometrySegment{Verb: verb, End: Point{s.End.X, s.End.Y}, Control1: Point{s.Control1.X, s.Control1.Y}, Control2: Point{s.Control2.X, s.Control2.Y}})
}
return result
}