mirror of
https://github.com/xiaoqidun/ofdgo.git
synced 2026-10-29 15:06:46 +08:00
205 lines
7.2 KiB
Go
205 lines
7.2 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"
|
|
"encoding/binary"
|
|
"image"
|
|
"math"
|
|
|
|
"github.com/tdewolff/canvas"
|
|
basefont "github.com/xiaoqidun/ofdgo/internal/base/font"
|
|
)
|
|
|
|
// canvasFontKey 按字体内容、名称及样式区分可复用的字体族，不依赖文档资源编号
|
|
type canvasFontKey struct {
|
|
digest [32]byte
|
|
name string
|
|
style canvas.FontStyle
|
|
}
|
|
|
|
// canvasClipCacheKey 区分不依赖文档资源的共享裁剪缓存
|
|
type canvasClipCacheKey struct{}
|
|
|
|
// canvasPathCacheKey 区分不依赖文档资源的共享局部路径缓存
|
|
type canvasPathCacheKey struct{}
|
|
|
|
// canvasFillCacheKey 区分按填充规则规范化的共享路径缓存
|
|
type canvasFillCacheKey struct{}
|
|
|
|
// canvasOutlineCacheKey 区分子渲染器共享的字体轮廓解析缓存
|
|
type canvasOutlineCacheKey struct{}
|
|
|
|
// canvasFillKey 保存完整几何摘要及填充规则
|
|
type canvasFillKey struct {
|
|
digest [32]byte
|
|
rule canvas.FillRule
|
|
}
|
|
|
|
// canvasPathKey 按完整路径文本与几何容差区分解析结果
|
|
type canvasPathKey struct {
|
|
data string
|
|
epsilon float64
|
|
}
|
|
|
|
// canvasBackendState 保存Canvas字体、字形和编码图片适配缓存
|
|
type canvasBackendState struct {
|
|
images renderCache[*EncodedImage, image.Image]
|
|
fontMap map[string]*canvas.FontFamily
|
|
svgFontCache map[*canvas.Font]SVGFont
|
|
textGlyphPathCache renderCache[textGlyphPathCacheKey, textGlyphPathCacheValue]
|
|
fontOutlines map[*canvas.Font]*basefont.Outliner
|
|
}
|
|
|
|
// canvasClipIntersections 获取子渲染器共享的几何交集缓存，限制结果保留量
|
|
// 返回: *renderCache[[32]byte, *canvas.Path] 裁剪缓存
|
|
func (r *Renderer) canvasClipIntersections() *renderCache[[32]byte, *canvas.Path] {
|
|
key := canvasClipCacheKey{}
|
|
if state, ok := r.sharedBackendStates[key]; ok {
|
|
return state.(*renderCache[[32]byte, *canvas.Path])
|
|
}
|
|
if r.sharedBackendStates == nil {
|
|
r.sharedBackendStates = make(map[any]any)
|
|
}
|
|
cache := &renderCache[[32]byte, *canvas.Path]{limit: 8 << 20}
|
|
r.sharedBackendStates[key] = cache
|
|
return cache
|
|
}
|
|
|
|
// canvasParsedPaths 获取子渲染器共享的局部路径缓存，不保留对象变换
|
|
// 返回: *renderCache[canvasPathKey, *canvas.Path] 路径缓存
|
|
func (r *Renderer) canvasParsedPaths() *renderCache[canvasPathKey, *canvas.Path] {
|
|
key := canvasPathCacheKey{}
|
|
if state, ok := r.sharedBackendStates[key]; ok {
|
|
return state.(*renderCache[canvasPathKey, *canvas.Path])
|
|
}
|
|
if r.sharedBackendStates == nil {
|
|
r.sharedBackendStates = make(map[any]any)
|
|
}
|
|
cache := &renderCache[canvasPathKey, *canvas.Path]{limit: 16 << 20}
|
|
r.sharedBackendStates[key] = cache
|
|
return cache
|
|
}
|
|
|
|
// canvasSettledPaths 获取共享填充轮廓缓存，限制结果保留量
|
|
// 返回: *renderCache[canvasFillKey, *canvas.Path] 填充轮廓缓存
|
|
func (r *Renderer) canvasSettledPaths() *renderCache[canvasFillKey, *canvas.Path] {
|
|
key := canvasFillCacheKey{}
|
|
if state, ok := r.sharedBackendStates[key]; ok {
|
|
return state.(*renderCache[canvasFillKey, *canvas.Path])
|
|
}
|
|
if r.sharedBackendStates == nil {
|
|
r.sharedBackendStates = make(map[any]any)
|
|
}
|
|
cache := &renderCache[canvasFillKey, *canvas.Path]{limit: 16 << 20}
|
|
r.sharedBackendStates[key] = cache
|
|
return cache
|
|
}
|
|
|
|
// canvasFontFamilies 获取子渲染器共享的只读字体族缓存，限制解析数据保留量
|
|
// 返回: *renderCache[canvasFontKey, *canvas.FontFamily] 字体族缓存
|
|
func (r *Renderer) canvasFontFamilies() *renderCache[canvasFontKey, *canvas.FontFamily] {
|
|
key := CanvasBackend{}
|
|
if state, ok := r.sharedBackendStates[key]; ok {
|
|
return state.(*renderCache[canvasFontKey, *canvas.FontFamily])
|
|
}
|
|
cache := &renderCache[canvasFontKey, *canvas.FontFamily]{limit: 32 << 20}
|
|
r.sharedBackendStates[key] = cache
|
|
return cache
|
|
}
|
|
|
|
// canvasFontOutlines 获取子渲染器共享的字体轮廓解析缓存，限制字体及解析数据保留量
|
|
// 返回: *renderCache[*canvas.Font, *basefont.Outliner] 字体轮廓缓存
|
|
func (r *Renderer) canvasFontOutlines() *renderCache[*canvas.Font, *basefont.Outliner] {
|
|
key := canvasOutlineCacheKey{}
|
|
if state, ok := r.sharedBackendStates[key]; ok {
|
|
return state.(*renderCache[*canvas.Font, *basefont.Outliner])
|
|
}
|
|
cache := &renderCache[*canvas.Font, *basefont.Outliner]{limit: 32 << 20}
|
|
r.sharedBackendStates[key] = cache
|
|
return cache
|
|
}
|
|
|
|
// canvasState 获取当前渲染器的Canvas私有缓存，按需创建且不向其他后端暴露
|
|
// 返回: *canvasBackendState Canvas缓存
|
|
func (r *Renderer) canvasState() *canvasBackendState {
|
|
key := CanvasBackend{}
|
|
if state, ok := r.backendStates[key]; ok {
|
|
return state.(*canvasBackendState)
|
|
}
|
|
state := &canvasBackendState{
|
|
images: renderCache[*EncodedImage, image.Image]{limit: imageCacheLimit},
|
|
}
|
|
state.resetFonts()
|
|
r.backendStates[key] = state
|
|
return state
|
|
}
|
|
|
|
// resetFonts 清除Canvas字体及字形缓存，保留编码图片适配对象
|
|
func (s *canvasBackendState) resetFonts() {
|
|
s.fontMap = make(map[string]*canvas.FontFamily)
|
|
s.svgFontCache = make(map[*canvas.Font]SVGFont)
|
|
s.textGlyphPathCache = renderCache[textGlyphPathCacheKey, textGlyphPathCacheValue]{limit: 16 << 20}
|
|
s.fontOutlines = make(map[*canvas.Font]*basefont.Outliner)
|
|
}
|
|
|
|
// canvasGeometryDigest 按完整坐标、路径顺序及几何容差计算摘要
|
|
// 入参: paths 非空路径序列
|
|
// 返回: [32]byte 几何摘要
|
|
func canvasGeometryDigest(paths ...*canvas.Path) [32]byte {
|
|
hash := sha256.New()
|
|
var data [512]byte
|
|
binary.LittleEndian.PutUint64(data[:8], math.Float64bits(canvas.Tolerance))
|
|
binary.LittleEndian.PutUint64(data[8:16], math.Float64bits(canvas.Epsilon))
|
|
binary.LittleEndian.PutUint64(data[16:24], math.Float64bits(canvas.BentleyOttmannEpsilon))
|
|
hash.Write(data[:24])
|
|
for _, path := range paths {
|
|
values := path.Data()
|
|
binary.LittleEndian.PutUint64(data[:8], uint64(len(values)))
|
|
hash.Write(data[:8])
|
|
for len(values) > 0 {
|
|
count := min(len(values), len(data)/8)
|
|
for i, value := range values[:count] {
|
|
binary.LittleEndian.PutUint64(data[i*8:], math.Float64bits(value))
|
|
}
|
|
hash.Write(data[:count*8])
|
|
values = values[count:]
|
|
}
|
|
}
|
|
var key [32]byte
|
|
hash.Sum(key[:0])
|
|
return key
|
|
}
|
|
|
|
// settleCanvasPath 复用复杂路径的填充规范化结果，返回独立副本
|
|
// 入参: path 页面坐标路径, rule 填充规则
|
|
// 返回: *canvas.Path 规范化填充轮廓
|
|
func (r *Renderer) settleCanvasPath(path *canvas.Path, rule canvas.FillRule) *canvas.Path {
|
|
if len(path.Data()) < 256 {
|
|
return path.Settle(rule)
|
|
}
|
|
key := canvasFillKey{digest: canvasGeometryDigest(path), rule: rule}
|
|
cache := r.canvasSettledPaths()
|
|
if result, ok := cache.get(key); ok {
|
|
return result.Copy()
|
|
}
|
|
result := path.Settle(rule)
|
|
if cost := len(result.Data())*8 + 256; cost <= cache.limit {
|
|
cache.put(key, result.Copy(), cost)
|
|
}
|
|
return result
|
|
}
|