doodle/pkg/scripting/pubsub.go
Noah Petherbridge 6def8f7625 Walk up slopes smoothly, texture freeing improvement
* Fix collision detection to allow actors to walk up slopes smoothly, without
  losing any horizontal velocity.
* Fix scrolling a level canvas so that chunks near the right or bottom edge
  of the viewpoint were getting culled prematurely.
* Centralize JavaScript exception catching logic to attach Go and JS stack
  traces where possible to be more useful for debugging.
* Performance: flush all SDL2 textures from memory between scene transitions
  in the app. Also add a `flush-textures` dev console command to flush the
  textures at any time - they all should regenerate if still needed based on
  underlying go.Images which can be garbage collected.
2024-02-07 22:14:48 -08:00

107 lines
2.7 KiB
Go

package scripting
import (
"git.kirsle.net/SketchyMaze/doodle/pkg/log"
"git.kirsle.net/SketchyMaze/doodle/pkg/scripting/exceptions"
"github.com/dop251/goja"
)
// Message holds data being published from one script VM with information sent
// to the linked VMs.
type Message struct {
Name string
SenderID string
Args []goja.Value
}
/*
RegisterPublishHooks adds the pub/sub hooks to a JavaScript VM.
This adds the global methods `Message.Subscribe(name, func)` and
`Message.Publish(name, args)` to the JavaScript VM's scope.
*/
func RegisterPublishHooks(s *Supervisor, vm *VM) {
// Goroutine to watch the VM's inbound channel and invoke Subscribe handlers
// for any matching messages received.
go func() {
// Catch any exceptions raised by the JavaScript VM.
defer func() {
if err := recover(); err != nil {
exceptions.FormatAndCatch(vm.vm, "RegisterPublishHooks(%s): %s: %s", vm.Name, err)
}
}()
// Watch the Inbound channel for PubSub messages and the stop channel for Teardown.
for {
select {
case <-vm.stop:
log.Debug("JavaScript VM %s stopping PubSub goroutine", vm.Name)
return
case msg := <-vm.Inbound:
vm.muSubscribe.Lock()
if _, ok := vm.subscribe[msg.Name]; ok {
for _, callback := range vm.subscribe[msg.Name] {
log.Debug("PubSub: %s receives from %s: %s", vm.Name, msg.SenderID, msg.Name)
if function, ok := goja.AssertFunction(callback); ok {
function(goja.Undefined(), msg.Args...)
}
}
}
vm.muSubscribe.Unlock()
}
}
}()
// Register the Message.Subscribe and Message.Publish functions.
vm.vm.Set("Message", map[string]interface{}{
"Subscribe": func(name string, callback goja.Value) {
vm.muSubscribe.Lock()
defer vm.muSubscribe.Unlock()
if _, ok := goja.AssertFunction(callback); !ok {
log.Error("SUBSCRIBE(%s): callback is not a function", name)
return
}
if _, ok := vm.subscribe[name]; !ok {
vm.subscribe[name] = []goja.Value{}
}
vm.subscribe[name] = append(vm.subscribe[name], callback)
},
"Publish": func(name string, v ...goja.Value) {
vm.muPublish.Lock()
for _, channel := range vm.Outbound {
channel <- Message{
Name: name,
SenderID: vm.Name,
Args: v,
}
}
vm.muPublish.Unlock()
},
"Broadcast": func(name string, v ...goja.Value) {
// Send the message to all actor VMs.
for _, toVM := range s.scripts {
if toVM == nil {
continue
}
if vm.Name == toVM.Name {
log.Debug("Broadcast(%s): skip to vm '%s' cuz it is the sender", name, toVM.Name)
continue
}
toVM.Inbound <- Message{
Name: name,
SenderID: vm.Name,
Args: v,
}
}
},
})
}