ebiten/internal/uidriver/js/ui.go
2019-12-01 03:31:32 +09:00

522 lines
13 KiB
Go

// Copyright 2015 Hajime Hoshi
//
// 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.
// +build js
package js
import (
"image"
"log"
"runtime"
"strconv"
"syscall/js"
"time"
"github.com/hajimehoshi/ebiten/internal/devicescale"
"github.com/hajimehoshi/ebiten/internal/driver"
)
type UserInterface struct {
width int
height int
scale float64
runnableInBackground bool
vsync bool
running bool
sizeChanged bool
contextLost bool
lastActualScale float64
context driver.UIContext
input Input
// pseudoScale is a value to store 'scale'. This doesn't affect actual rendering.
// This is for backward compatibility.
pseudoScale float64
}
var theUI = &UserInterface{
sizeChanged: true,
vsync: true,
}
func init() {
theUI.input.ui = theUI
}
func Get() *UserInterface {
return theUI
}
var (
window = js.Global().Get("window")
document = js.Global().Get("document")
canvas js.Value
requestAnimationFrame = window.Get("requestAnimationFrame")
setTimeout = window.Get("setTimeout")
)
func (u *UserInterface) ScreenSizeInFullscreen() (int, int) {
return window.Get("innerWidth").Int(), window.Get("innerHeight").Int()
}
func (u *UserInterface) SetScreenSize(width, height int) {
u.setScreenSize(width, height)
}
func (u *UserInterface) SetScreenScale(scale float64) {
u.pseudoScale = scale
}
func (u *UserInterface) ScreenScale() float64 {
return u.pseudoScale
}
func (u *UserInterface) SetFullscreen(fullscreen bool) {
// Do nothing
}
func (u *UserInterface) IsFullscreen() bool {
return false
}
func (u *UserInterface) SetRunnableInBackground(runnableInBackground bool) {
u.runnableInBackground = runnableInBackground
}
func (u *UserInterface) IsRunnableInBackground() bool {
return u.runnableInBackground
}
func (u *UserInterface) SetVsyncEnabled(enabled bool) {
u.vsync = enabled
}
func (u *UserInterface) IsVsyncEnabled() bool {
return u.vsync
}
func (u *UserInterface) ScreenPadding() (x0, y0, x1, y1 float64) {
return 0, 0, 0, 0
}
func (u *UserInterface) adjustPosition(x, y int) (int, int) {
rect := canvas.Call("getBoundingClientRect")
x -= rect.Get("left").Int()
y -= rect.Get("top").Int()
s := u.scale
return int(float64(x) / s), int(float64(y) / s)
}
func (u *UserInterface) IsCursorVisible() bool {
// The initial value is an empty string, so don't compare with "auto" here.
return canvas.Get("style").Get("cursor").String() != "none"
}
func (u *UserInterface) SetCursorVisible(visible bool) {
if visible {
canvas.Get("style").Set("cursor", "auto")
} else {
canvas.Get("style").Set("cursor", "none")
}
}
func (u *UserInterface) SetWindowTitle(title string) {
document.Set("title", title)
}
func (u *UserInterface) SetWindowIcon(iconImages []image.Image) {
// Do nothing
}
func (u *UserInterface) IsWindowDecorated() bool {
return false
}
func (u *UserInterface) SetWindowDecorated(decorated bool) {
// Do nothing
}
func (u *UserInterface) IsWindowResizable() bool {
return false
}
func (u *UserInterface) SetWindowResizable(decorated bool) {
// Do nothing
if u.running {
panic("js: SetWindowResizable can't be called after the main loop starts")
}
}
func (u *UserInterface) DeviceScaleFactor() float64 {
return devicescale.GetAt(0, 0)
}
func (u *UserInterface) actualScreenScale() float64 {
// CSS imageRendering property seems useful to enlarge the screen,
// but doesn't work in some cases (#306):
// * Chrome just after restoring the lost context
// * Safari
// Let's use the devicePixelRatio as it is here.
return u.scale * devicescale.GetAt(0, 0)
}
func (u *UserInterface) updateSize() {
a := u.actualScreenScale()
if u.lastActualScale != a {
u.updateScreenSize()
}
u.lastActualScale = a
if u.sizeChanged {
u.sizeChanged = false
u.context.SetSize(u.width, u.height, a)
}
}
func (u *UserInterface) suspended() bool {
if u.runnableInBackground {
return false
}
if !document.Call("hasFocus").Bool() {
return true
}
if document.Get("hidden").Bool() {
return true
}
return false
}
func (u *UserInterface) update() error {
if u.suspended() {
u.context.SuspendAudio()
return nil
}
u.context.ResumeAudio()
u.input.UpdateGamepads()
u.updateSize()
if err := u.context.Update(func() {
u.updateSize()
}); err != nil {
return err
}
return nil
}
func (u *UserInterface) loop(context driver.UIContext) <-chan error {
u.context = context
ch := make(chan error)
var cf js.Func
f := func(this js.Value, args []js.Value) interface{} {
if u.contextLost {
requestAnimationFrame.Invoke(cf)
return nil
}
if err := u.update(); err != nil {
ch <- err
close(ch)
return nil
}
if u.vsync {
requestAnimationFrame.Invoke(cf)
} else {
setTimeout.Invoke(cf, 0)
}
return nil
}
// TODO: Should cf be released after the game ends?
cf = js.FuncOf(f)
// Call f asyncly to be async since ch is used in f.
go func() {
f(js.Value{}, nil)
}()
// Run another loop to watch suspended() as the above update function is never called when the tab is hidden.
// To check the document's visiblity, visibilitychange event should usually be used. However, this event is
// not reliable and sometimes it is not fired (#961). Then, watch the state regularly instead.
go func() {
t := time.NewTicker(100 * time.Millisecond)
defer t.Stop()
for range t.C {
if u.suspended() {
u.context.SuspendAudio()
} else {
u.context.ResumeAudio()
}
}
}()
return ch
}
func init() {
if document.Get("body") == js.Null() {
ch := make(chan struct{})
window.Call("addEventListener", "load", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
close(ch)
return nil
}))
<-ch
}
window.Call("addEventListener", "resize", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
theUI.updateScreenSize()
return nil
}))
// Adjust the initial scale to 1.
// https://developer.mozilla.org/en/docs/Mozilla/Mobile/Viewport_meta_tag
meta := document.Call("createElement", "meta")
meta.Set("name", "viewport")
meta.Set("content", "width=device-width, initial-scale=1")
document.Get("head").Call("appendChild", meta)
canvas = document.Call("createElement", "canvas")
canvas.Set("width", 16)
canvas.Set("height", 16)
document.Get("body").Call("appendChild", canvas)
htmlStyle := document.Get("documentElement").Get("style")
htmlStyle.Set("height", "100%")
htmlStyle.Set("margin", "0")
htmlStyle.Set("padding", "0")
bodyStyle := document.Get("body").Get("style")
bodyStyle.Set("backgroundColor", "#000")
bodyStyle.Set("position", "relative")
bodyStyle.Set("height", "100%")
bodyStyle.Set("margin", "0")
bodyStyle.Set("padding", "0")
bodyStyle.Set("display", "flex")
bodyStyle.Set("alignItems", "center")
bodyStyle.Set("justifyContent", "center")
// TODO: This is OK as long as the game is in an independent iframe.
// What if the canvas is embedded in a HTML directly?
document.Get("body").Call("addEventListener", "click", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
canvas.Call("focus")
return nil
}))
canvasStyle := canvas.Get("style")
canvasStyle.Set("position", "absolute")
// Make the canvas focusable.
canvas.Call("setAttribute", "tabindex", 1)
canvas.Get("style").Set("outline", "none")
// Keyboard
canvas.Call("addEventListener", "keydown", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
// Focus the canvas explicitly to activate tha game (#961).
canvas.Call("focus")
e := args[0]
// Don't 'preventDefault' on keydown events or keypress events wouldn't work (#715).
theUI.input.Update(e)
return nil
}))
canvas.Call("addEventListener", "keypress", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
e := args[0]
e.Call("preventDefault")
theUI.input.Update(e)
return nil
}))
canvas.Call("addEventListener", "keyup", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
e := args[0]
e.Call("preventDefault")
theUI.input.Update(e)
return nil
}))
// Mouse
canvas.Call("addEventListener", "mousedown", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
// Focus the canvas explicitly to activate tha game (#961).
canvas.Call("focus")
e := args[0]
e.Call("preventDefault")
theUI.input.Update(e)
return nil
}))
canvas.Call("addEventListener", "mouseup", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
e := args[0]
e.Call("preventDefault")
theUI.input.Update(e)
return nil
}))
canvas.Call("addEventListener", "mousemove", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
e := args[0]
e.Call("preventDefault")
theUI.input.Update(e)
return nil
}))
canvas.Call("addEventListener", "wheel", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
e := args[0]
e.Call("preventDefault")
theUI.input.Update(e)
return nil
}))
// Touch
canvas.Call("addEventListener", "touchstart", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
// Focus the canvas explicitly to activate tha game (#961).
canvas.Call("focus")
e := args[0]
e.Call("preventDefault")
theUI.input.Update(e)
return nil
}))
canvas.Call("addEventListener", "touchend", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
e := args[0]
e.Call("preventDefault")
theUI.input.Update(e)
return nil
}))
canvas.Call("addEventListener", "touchmove", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
e := args[0]
e.Call("preventDefault")
theUI.input.Update(e)
return nil
}))
// Gamepad
window.Call("addEventListener", "gamepadconnected", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
// Do nothing.
return nil
}))
canvas.Call("addEventListener", "contextmenu", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
e := args[0]
e.Call("preventDefault")
return nil
}))
// Context
canvas.Call("addEventListener", "webglcontextlost", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
e := args[0]
e.Call("preventDefault")
theUI.contextLost = true
return nil
}))
canvas.Call("addEventListener", "webglcontextrestored", js.FuncOf(func(this js.Value, args []js.Value) interface{} {
theUI.contextLost = false
return nil
}))
}
func (u *UserInterface) Run(width, height int, scale float64, title string, context driver.UIContext, graphics driver.Graphics) error {
// scale is ignored.
document.Set("title", title)
u.setScreenSize(width, height)
u.pseudoScale = scale
canvas.Call("focus")
u.running = true
ch := u.loop(context)
if runtime.GOARCH == "wasm" {
return <-ch
}
// On GopherJS, the main goroutine cannot be blocked due to the bug (gopherjs/gopherjs#826).
// Return immediately.
go func() {
defer func() {
u.running = false
}()
if err := <-ch; err != nil {
log.Fatal(err)
}
}()
return nil
}
func (u *UserInterface) RunWithoutMainLoop(width, height int, scale float64, title string, context driver.UIContext, graphics driver.Graphics) <-chan error {
panic("js: RunWithoutMainLoop is not implemented")
}
func (u *UserInterface) setScreenSize(width, height int) bool {
if u.width == width && u.height == height {
return false
}
u.width = width
u.height = height
u.updateScreenSize()
return true
}
func (u *UserInterface) updateScreenSize() {
body := document.Get("body")
bw := body.Get("clientWidth").Float()
bh := body.Get("clientHeight").Float()
sw := bw / float64(u.width)
sh := bh / float64(u.height)
if sw > sh {
u.scale = sh
} else {
u.scale = sw
}
canvas.Set("width", int(float64(u.width)*u.actualScreenScale()))
canvas.Set("height", int(float64(u.height)*u.actualScreenScale()))
canvasStyle := canvas.Get("style")
cssWidth := int(float64(u.width) * u.scale)
cssHeight := int(float64(u.height) * u.scale)
canvasStyle.Set("width", strconv.Itoa(cssWidth)+"px")
canvasStyle.Set("height", strconv.Itoa(cssHeight)+"px")
u.sizeChanged = true
}
func (u *UserInterface) SetWindowPosition(x, y int) {
// Do nothing
}
func (u *UserInterface) WindowPosition() (int, int) {
if !u.running {
panic("js: WindowPosition can't be called before the main loop starts")
}
return 0, 0
}
func (u *UserInterface) SetScreenTransparent(transparent bool) {
if u.running {
panic("js: SetScreenTransparent can't be called after the main loop starts")
}
bodyStyle := document.Get("body").Get("style")
if transparent {
bodyStyle.Set("backgroundColor", "transparent")
} else {
bodyStyle.Set("backgroundColor", "#000")
}
}
func (u *UserInterface) IsScreenTransparent() bool {
bodyStyle := document.Get("body").Get("style")
return bodyStyle.Get("backgroundColor").String() == "transparent"
}
func (u *UserInterface) Input() driver.Input {
return &u.input
}