ebiten/internal/ui/ui_glfw.go

223 lines
5.0 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 ui
import (
"fmt"
"runtime"
"time"
"github.com/go-gl/glfw/v3.1/glfw"
"github.com/hajimehoshi/ebiten/internal/graphics/opengl"
)
func Now() int64 {
return time.Now().UnixNano()
}
var currentUI *userInterface
func Init() *opengl.Context {
runtime.LockOSThread()
err := glfw.Init()
if err != nil {
panic(fmt.Sprintf("glfw.Init() fails: %v", 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 {
panic(err)
}
u := &userInterface{
window: window,
}
ch := make(chan struct{})
go func() {
runtime.LockOSThread()
u.window.MakeContextCurrent()
glfw.SwapInterval(1)
u.context = opengl.NewContext()
close(ch)
u.context.Loop()
}()
currentUI = u
<-ch
u.context.Init()
return u.context
}
func Start(width, height, scale int, title string) error {
return currentUI.start(width, height, scale, title)
}
func Terminate() {
currentUI.terminate()
}
func DoEvents() error {
return currentUI.doEvents()
}
func IsClosed() bool {
return currentUI.isClosed()
}
func SwapBuffers() {
currentUI.swapBuffers()
}
func SetScreenSize(width, height int) bool {
return currentUI.setScreenSize(width, height, currentUI.scale)
}
func SetScreenScale(scale int) bool {
return currentUI.setScreenSize(currentUI.width, currentUI.height, scale)
}
func ActualScale() int {
return currentUI.actualScale()
}
type userInterface struct {
window *glfw.Window
width int
height int
scale int
deviceScale float64
framebufferScale int
context *opengl.Context
}
func (u *userInterface) start(width, height, scale int, title string) error {
m := glfw.GetPrimaryMonitor()
v := m.GetVideoMode()
mw, _ := m.GetPhysicalSize()
u.deviceScale = 1
u.framebufferScale = 1
// mw can be 0 on some environment like Linux VM
if 0 < mw {
dpi := float64(v.Width) * 25.4 / float64(mw)
u.deviceScale = dpi / 96
if u.deviceScale < 1 {
u.deviceScale = 1
}
}
u.setScreenSize(width, height, scale)
u.window.SetTitle(title)
u.window.Show()
x := (v.Width - width*u.windowScale()) / 2
y := (v.Height - height*u.windowScale()) / 3
u.window.SetPos(x, y)
return nil
}
func (u *userInterface) windowScale() int {
return u.scale * int(u.deviceScale)
}
func (u *userInterface) actualScale() int {
return u.windowScale() * u.framebufferScale
}
func (u *userInterface) pollEvents() error {
glfw.PollEvents()
return updateInput(u.window, u.windowScale())
}
func (u *userInterface) doEvents() 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.isClosed() {
return nil
}
}
return nil
}
func (u *userInterface) terminate() {
glfw.Terminate()
}
func (u *userInterface) isClosed() bool {
return u.window.ShouldClose()
}
func (u *userInterface) swapBuffers() {
// The bound framebuffer must be the default one (0) before swapping buffers.
u.context.BindZeroFramebuffer()
// Call glFinish before glfwSwapBuffer to make sure
// all OpenGL tasks are executed.
u.context.Finish()
u.context.RunOnContextThread(func() {
u.window.SwapBuffers()
})
}
func (u *userInterface) setScreenSize(width, height, scale int) bool {
if u.width == width && u.height == height && u.scale == scale {
return false
}
// These properties should be set first since this affects windowScale().
u.width = width
u.height = height
u.scale = scale
// To make sure the current existing framebuffers are rendered,
// swap buffers here before SetSize is called.
u.swapBuffers()
ch := make(chan struct{})
window := u.window
window.SetFramebufferSizeCallback(func(w *glfw.Window, width, height int) {
window.SetFramebufferSizeCallback(nil)
close(ch)
})
window.SetSize(width*u.windowScale(), height*u.windowScale())
event:
for {
glfw.PollEvents()
select {
case <-ch:
break event
default:
}
}
// This is usually 1, but sometimes more than 1 (e.g. Retina Mac)
fw, _ := window.GetFramebufferSize()
u.framebufferScale = fw / width / u.windowScale()
return true
}