doodle/pkg/doodads/json.go
Noah Petherbridge 8603c43c58 Gzip Compression for Levels and Doodads
* Levels and Doodad files will be written in gzip-compressed JSON format
* `boolProp compress-drawings false` to disable compression and save as
  classic JSON format directly
* The game can still read uncompressed JSON files

The file size savings on some built-in assets:

* Tutorial 2.level: 2.2M -> 414K (82% smaller)
* warp-door-orange.doodad: 105K -> 17K (84% smaller)
2021-07-13 20:06:57 -07:00

87 lines
2.0 KiB
Go

package doodads
import (
"bytes"
"encoding/json"
"fmt"
"io/ioutil"
"path/filepath"
"git.kirsle.net/apps/doodle/pkg/balance"
"git.kirsle.net/apps/doodle/pkg/log"
"git.kirsle.net/apps/doodle/pkg/usercfg"
)
// ToJSON serializes the doodad as JSON (gzip supported).
//
// If balance.CompressLevels=true the doodad will be gzip compressed
// and the return value is gz bytes and not the raw JSON.
func (d *Doodad) ToJSON() ([]byte, error) {
// Gzip compressing?
if balance.CompressDrawings {
return d.ToGzip()
}
out := bytes.NewBuffer([]byte{})
encoder := json.NewEncoder(out)
if usercfg.Current.JSONIndent {
encoder.SetIndent("", "\t")
}
err := encoder.Encode(d)
return out.Bytes(), err
}
// FromJSON loads a doodad from JSON string (gzip supported).
func FromJSON(filename string, data []byte) (*Doodad, error) {
var doodad = &Doodad{}
// Inspect the headers of the file to see how it was encoded.
if len(data) > 0 && data[0] == '{' {
// Looks standard JSON.
err := json.Unmarshal(data, doodad)
if err != nil {
return nil, err
}
} else if len(data) > 1 && data[0] == 0x1f && data[1] == 0x8b {
// Gzip compressed. `1F8B` is gzip magic number.
log.Debug("Decompress doodad %s", filename)
if gzd, err := FromGzip(data); err != nil {
return nil, err
} else {
doodad = gzd
}
}
// Inflate the chunk metadata to map the pixels to their palette indexes.
doodad.Filename = filepath.Base(filename)
doodad.Inflate()
return doodad, nil
}
// WriteJSON writes a Doodad to JSON on disk.
func (d *Doodad) WriteJSON(filename string) error {
json, err := d.ToJSON()
if err != nil {
return fmt.Errorf("Doodad.WriteJSON: JSON encode error: %s", err)
}
err = ioutil.WriteFile(filename, json, 0755)
if err != nil {
return fmt.Errorf("Doodad.WriteJSON: WriteFile error: %s", err)
}
d.Filename = filepath.Base(filename)
return nil
}
// LoadJSON loads a map from JSON file.
func LoadJSON(filename string) (*Doodad, error) {
data, err := ioutil.ReadFile(filename)
if err != nil {
return nil, err
}
return FromJSON(filename, data)
}