converted earcut.hpp library to Go and used it to triangulate fonts

canvas.go

@@ -27,10 +27,11 @@ type Canvas struct {
  state drawState
  stateStack []drawState
 
- images map[interface{}]*Image
- fonts map[interface{}]*Font
- fontCtxs map[fontKey]*frCache
- fontTriCache map[*Font]*fontTriCache
+ images map[interface{}]*Image
+ fonts map[interface{}]*Font
+ fontCtxs map[fontKey]*frCache
+ fontPathCache map[*Font]*fontPathCache
+ fontTriCache map[*Font]*fontTriCache
 
  shadowBuf []backendbase.Vec
 }
@@ -139,12 +140,13 @@ var Performance = struct {
 // coordinates given here also use the bottom left as origin
 func New(backend backendbase.Backend) *Canvas {
  cv := &Canvas{
- b: backend,
- stateStack: make([]drawState, 0, 20),
- images: make(map[interface{}]*Image),
- fonts: make(map[interface{}]*Font),
- fontCtxs: make(map[fontKey]*frCache),
- fontTriCache: make(map[*Font]*fontTriCache),
+ b: backend,
+ stateStack: make([]drawState, 0, 20),
+ images: make(map[interface{}]*Image),
+ fonts: make(map[interface{}]*Font),
+ fontCtxs: make(map[fontKey]*frCache),
+ fontPathCache: make(map[*Font]*fontPathCache),
+ fontTriCache: make(map[*Font]*fontTriCache),
  }
  cv.state.lineWidth = 1
  cv.state.lineAlpha = 1
@@ -482,6 +484,7 @@ func (cv *Canvas) reduceCache(keepSize, rec int) {
  oldest := time.Now()
  var oldestFontKey fontKey
  var oldestFontKey2 *Font
+ var oldestFontKey3 *Font
  var oldestImageKey interface{}
  for src, img := range cv.images {
  w, h := img.img.Size()
@@ -499,7 +502,7 @@ func (cv *Canvas) reduceCache(keepSize, rec int) {
  oldestImageKey = nil
  }
  }
- for fnt, cache := range cv.fontTriCache {
+ for fnt, cache := range cv.fontPathCache {
  total += cache.size()
  if cache.lastUsed.Before(oldest) {
  oldest = cache.lastUsed
@@ -508,6 +511,16 @@ func (cv *Canvas) reduceCache(keepSize, rec int) {
  oldestImageKey = nil
  }
  }
+ for fnt, cache := range cv.fontTriCache {
+ total += cache.size()
+ if cache.lastUsed.Before(oldest) {
+ oldest = cache.lastUsed
+ oldestFontKey3 = fnt
+ oldestFontKey2 = nil
+ oldestFontKey = fontKey{}
+ oldestImageKey = nil
+ }
+ }
  if total <= keepSize {
  return
  }
@@ -516,7 +529,9 @@ func (cv *Canvas) reduceCache(keepSize, rec int) {
  cv.images[oldestImageKey].Delete()
  delete(cv.images, oldestImageKey)
  } else if oldestFontKey2 != nil {
- delete(cv.fontTriCache, oldestFontKey2)
+ delete(cv.fontPathCache, oldestFontKey2)
+ } else if oldestFontKey3 != nil {
+ delete(cv.fontTriCache, oldestFontKey3)
  } else {
  cv.fontCtxs[oldestFontKey].ctx = nil
  delete(cv.fontCtxs, oldestFontKey)