ebiten/internal/ui/ui_glfw.go
2016-09-03 02:12:11 +09:00

318 lines
6.7 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 darwin,!arm,!arm64 linux windows
// +build !js
// +build !android
// +build !ios
package ui
import (
"errors"
"runtime"
"time"
"github.com/go-gl/glfw/v3.1/glfw"
"github.com/hajimehoshi/ebiten/internal/graphics/opengl"
)
type userInterface struct {
window *glfw.Window
width int
height int
scale float64
funcs chan func()
sizeChanged bool
}
var currentUI *userInterface
func init() {
if err := initialize(); err != nil {
panic(err)
}
}
func initialize() error {
runtime.LockOSThread()
if err := glfw.Init(); err != nil {
return err
}
glfw.WindowHint(glfw.Visible, glfw.False)
glfw.WindowHint(glfw.Resizable, glfw.False)
glfw.WindowHint(glfw.ContextVersionMajor, 2)
glfw.WindowHint(glfw.ContextVersionMinor, 1)
// As start, create an window with temporary size to create OpenGL context thread.
window, err := glfw.CreateWindow(16, 16, "", nil, nil)
if err != nil {
return err
}
u := &userInterface{
window: window,
funcs: make(chan func()),
sizeChanged: true,
}
u.window.MakeContextCurrent()
glfw.SwapInterval(1)
currentUI = u
return nil
}
func RunMainThreadLoop(ch <-chan error) error {
// TODO: Check this is done on the main thread.
for {
select {
case f := <-currentUI.funcs:
f()
case err := <-ch:
// ch returns a value not only when an error occur but also it is closed.
return err
}
}
}
func (u *userInterface) runOnMainThread(f func() error) error {
if u.funcs == nil {
// already closed
return nil
}
ch := make(chan struct{})
var err error
u.funcs <- func() {
err = f()
close(ch)
}
<-ch
return err
}
func SetScreenSize(width, height int) (bool, error) {
u := currentUI
r := false
if err := u.runOnMainThread(func() error {
var err error
r, err = u.setScreenSize(width, height, u.scale)
if err != nil {
return err
}
return nil
}); err != nil {
return false, err
}
return r, nil
}
func SetScreenScale(scale float64) (bool, error) {
u := currentUI
r := false
if err := u.runOnMainThread(func() error {
var err error
r, err = u.setScreenSize(u.width, u.height, scale)
if err != nil {
return err
}
return nil
}); err != nil {
return false, err
}
return r, nil
}
func ScreenScale() float64 {
u := currentUI
s := 0.0
_ = u.runOnMainThread(func() error {
s = u.scale
return nil
})
return s
}
func Run(width, height int, scale float64, title string, g GraphicsContext) error {
u := currentUI
// GLContext must be created before setting the screen size, which requires
// swapping buffers.
var err error
glContext, err = opengl.NewContext(currentUI.runOnMainThread)
if err != nil {
return err
}
if err := u.runOnMainThread(func() error {
m := glfw.GetPrimaryMonitor()
v := m.GetVideoMode()
r, err := u.setScreenSize(width, height, scale)
if err != nil {
return err
}
if !r {
return errors.New("ui: Fail to set the screen size")
}
u.window.SetTitle(title)
u.window.Show()
w, h := u.glfwSize()
x := (v.Width - w) / 2
y := (v.Height - h) / 3
u.window.SetPos(x, y)
return nil
}); err != nil {
return err
}
return u.loop(g)
}
func (u *userInterface) glfwSize() (int, int) {
return int(float64(u.width) * u.scale * glfwScale()), int(float64(u.height) * u.scale * glfwScale())
}
func (u *userInterface) actualScreenScale() float64 {
return u.scale * deviceScale()
}
func (u *userInterface) pollEvents() error {
glfw.PollEvents()
return currentInput.update(u.window, u.scale*glfwScale())
}
func (u *userInterface) update(g GraphicsContext) error {
shouldClose := false
_ = u.runOnMainThread(func() error {
shouldClose = u.window.ShouldClose()
return nil
})
if shouldClose {
return &RegularTermination{}
}
actualScale := 0.0
_ = u.runOnMainThread(func() error {
if !u.sizeChanged {
return nil
}
u.sizeChanged = false
actualScale = u.actualScreenScale()
return nil
})
if 0 < actualScale {
if err := g.SetSize(u.width, u.height, actualScale); err != nil {
return err
}
}
if err := u.runOnMainThread(func() error {
if err := u.pollEvents(); err != nil {
return err
}
for u.window.GetAttrib(glfw.Focused) == 0 {
// Wait for an arbitrary period to avoid busy loop.
time.Sleep(time.Second / 60)
if err := u.pollEvents(); err != nil {
return err
}
if u.window.ShouldClose() {
return nil
}
}
return nil
}); err != nil {
return err
}
if err := g.Update(); err != nil {
return err
}
return nil
}
func (u *userInterface) loop(g GraphicsContext) error {
defer func() {
_ = u.runOnMainThread(func() error {
glfw.Terminate()
return nil
})
}()
for {
if err := u.update(g); err != nil {
return err
}
// The bound framebuffer must be the default one (0) before swapping buffers.
if err := glContext.BindScreenFramebuffer(); err != nil {
return err
}
if err := u.runOnMainThread(func() error {
return u.swapBuffers()
}); err != nil {
return err
}
}
}
func (u *userInterface) swapBuffers() error {
u.window.SwapBuffers()
return nil
}
func (u *userInterface) FinishRendering() error {
return nil
}
func (u *userInterface) setScreenSize(width, height int, scale float64) (bool, error) {
if u.width == width && u.height == height && u.scale == scale {
return false, nil
}
origScale := u.scale
u.scale = scale
// On Windows, giving a too small width doesn't call a callback (#165).
// To prevent hanging up, return asap if the width is too small.
// 252 is an arbitrary number and I guess this is small enough.
const minWindowWidth = 252
if int(float64(width)*u.actualScreenScale()) < minWindowWidth {
u.scale = origScale
return false, nil
}
u.width = width
u.height = height
// To make sure the current existing framebuffers are rendered,
// swap buffers here before SetSize is called.
if err := u.swapBuffers(); err != nil {
return false, err
}
ch := make(chan struct{})
window := u.window
window.SetFramebufferSizeCallback(func(_ *glfw.Window, width, height int) {
window.SetFramebufferSizeCallback(nil)
close(ch)
})
w, h := u.glfwSize()
window.SetSize(w, h)
event:
for {
glfw.PollEvents()
select {
case <-ch:
break event
default:
}
}
u.sizeChanged = true
return true, nil
}