erm/vendor/github.com/lxn/walk/iconcache.go

91 lines
1.7 KiB
Go

// Copyright 2019 The Walk Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build windows
package walk
var iconCache *IconCache
func init() {
AppendToWalkInit(func() {
iconCache = NewIconCache()
})
}
type IconCache struct {
imageAndDPI2Bitmap map[imageAndDPI]*Bitmap
imageAndDPI2Icon map[imageAndDPI]*Icon
}
type imageAndDPI struct {
image Image
dpi int
}
func NewIconCache() *IconCache {
return &IconCache{
imageAndDPI2Bitmap: make(map[imageAndDPI]*Bitmap),
imageAndDPI2Icon: make(map[imageAndDPI]*Icon),
}
}
func (ic *IconCache) Clear() {
for key, bmp := range ic.imageAndDPI2Bitmap {
bmp.Dispose()
delete(ic.imageAndDPI2Bitmap, key)
}
for key, ico := range ic.imageAndDPI2Icon {
ico.Dispose()
delete(ic.imageAndDPI2Icon, key)
}
}
func (ic *IconCache) Dispose() {
ic.Clear()
}
func (ic *IconCache) Bitmap(image Image, dpi int) (*Bitmap, error) {
key := imageAndDPI{image, dpi}
if bmp, ok := ic.imageAndDPI2Bitmap[key]; ok {
return bmp, nil
}
size := SizeFrom96DPI(image.Size(), dpi)
bmp, err := NewBitmapFromImageWithSize(image, size)
if err != nil {
return nil, err
}
ic.imageAndDPI2Bitmap[key] = bmp
return bmp, nil
}
func (ic *IconCache) Icon(image Image, dpi int) (*Icon, error) {
key := imageAndDPI{image, dpi}
if ico, ok := ic.imageAndDPI2Icon[key]; ok {
return ico, nil
}
if ico, ok := image.(*Icon); ok {
if ico.handleForDPI(dpi) != 0 {
ic.imageAndDPI2Icon[key] = ico
return ico, nil
}
}
ico, err := newIconFromImageForDPI(image, dpi)
if err != nil {
return nil, err
}
ic.imageAndDPI2Icon[key] = ico
return ico, nil
}