ebiten/internal/ui/monitor_glfw.go
2024-03-03 23:27:02 +09:00

179 lines
4.3 KiB
Go

// Copyright 2023 The Ebitengine Authors
//
// 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.
//go:build !android && !ios && !js && !nintendosdk && !playstation5
package ui
import (
"image"
"sync"
"sync/atomic"
"github.com/hajimehoshi/ebiten/v2/internal/glfw"
)
// Monitor is a wrapper around glfw.Monitor.
type Monitor struct {
m *glfw.Monitor
videoMode *glfw.VidMode
id int
name string
boundsInGLFWPixels image.Rectangle
contentScale float64
}
// Name returns the monitor's name.
func (m *Monitor) Name() string {
return m.name
}
// DeviceScaleFactor is concurrent-safe as contentScale is immutable.
func (m *Monitor) DeviceScaleFactor() float64 {
// It is rare, but monitor can be nil when glfw.GetPrimaryMonitor returns nil.
// In this case, return 1 as a tentative scale (#1878).
if m == nil {
return 1
}
return m.contentScale
}
func (m *Monitor) sizeInDIP() (float64, float64) {
w, h := m.boundsInGLFWPixels.Dx(), m.boundsInGLFWPixels.Dy()
s := m.DeviceScaleFactor()
return dipFromGLFWPixel(float64(w), s), dipFromGLFWPixel(float64(h), s)
}
type monitors struct {
// monitors is the monitor list cache for desktop glfw compile targets.
// populated by 'updateMonitors' which is called on init and every
// monitor config change event.
monitors []*Monitor
m sync.Mutex
updateCalled int32
}
var theMonitors monitors
func (m *monitors) append(ms []*Monitor) []*Monitor {
if atomic.LoadInt32(&m.updateCalled) == 0 {
panic("ui: (*monitors).update must be called before (*monitors).append is called")
}
m.m.Lock()
defer m.m.Unlock()
return append(ms, m.monitors...)
}
func (m *monitors) primaryMonitor() *Monitor {
if atomic.LoadInt32(&m.updateCalled) == 0 {
panic("ui: (*monitors).update must be called before (*monitors).primaryMonitor is called")
}
m.m.Lock()
defer m.m.Unlock()
return m.monitors[0]
}
func (m *monitors) monitorFromID(id int) *Monitor {
m.m.Lock()
defer m.m.Unlock()
return m.monitors[id]
}
// monitorFromPosition returns a monitor for the given position (x, y),
// or returns nil if monitor is not found.
// The position is in GLFW pixels.
func (m *monitors) monitorFromPosition(x, y int) *Monitor {
m.m.Lock()
defer m.m.Unlock()
for _, m := range m.monitors {
// Use an inclusive range. On macOS, the cursor position can take this range (#2794).
b := m.boundsInGLFWPixels
if b.Min.X <= x && x <= b.Max.X && b.Min.Y <= y && y <= b.Max.Y {
return m
}
}
return nil
}
// update must be called from the main thread.
func (m *monitors) update() error {
glfwMonitors, err := glfw.GetMonitors()
if err != nil {
return err
}
newMonitors := make([]*Monitor, 0, len(glfwMonitors))
for i, m := range glfwMonitors {
x, y, err := m.GetPos()
if err != nil {
return err
}
// TODO: Detect the update of the content scale by SetContentScaleCallback (#2343).
contentScale := 1.0
// Keep calling GetContentScale until the returned scale is 0 (#2051).
// Retry this at most 5 times to avoid an infinite loop.
for i := 0; i < 5; i++ {
// An error can happen e.g. when entering a screensaver on Windows (#2488).
sx, _, err := m.GetContentScale()
if err != nil {
continue
}
if sx == 0 {
continue
}
contentScale = float64(sx)
break
}
videoMode, err := m.GetVideoMode()
if err != nil {
return err
}
name, err := m.GetName()
if err != nil {
return err
}
w, h, err := glfwMonitorSizeInGLFWPixels(m)
if err != nil {
return err
}
b := image.Rect(x, y, x+w, y+h)
newMonitors = append(newMonitors, &Monitor{
m: m,
videoMode: videoMode,
id: i,
name: name,
boundsInGLFWPixels: b,
contentScale: contentScale,
})
}
m.m.Lock()
m.monitors = newMonitors
m.m.Unlock()
atomic.StoreInt32(&m.updateCalled, 1)
return nil
}