ebiten/run.go
2022-02-06 18:13:45 +09:00

466 lines
15 KiB
Go

// Copyright 2014 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.
package ebiten
import (
"sync/atomic"
"github.com/hajimehoshi/ebiten/v2/internal/clock"
"github.com/hajimehoshi/ebiten/v2/internal/graphicscommand"
"github.com/hajimehoshi/ebiten/v2/internal/ui"
)
// Game defines necessary functions for a game.
type Game interface {
// Update updates a game by one tick. The given argument represents a screen image.
//
// Update updates only the game logic and Draw draws the screen.
//
// In the first frame, it is ensured that Update is called at least once before Draw. You can use Update
// to initialize the game state.
//
// After the first frame, Update might not be called or might be called once
// or more for one frame. The frequency is determined by the current TPS (tick-per-second).
Update() error
// Draw draws the game screen by one frame.
//
// The give argument represents a screen image. The updated content is adopted as the game screen.
Draw(screen *Image)
// Layout accepts a native outside size in device-independent pixels and returns the game's logical screen
// size.
//
// On desktops, the outside is a window or a monitor (fullscreen mode). On browsers, the outside is a body
// element. On mobiles, the outside is the view's size.
//
// Even though the outside size and the screen size differ, the rendering scale is automatically adjusted to
// fit with the outside.
//
// Layout is called almost every frame.
//
// It is ensured that Layout is invoked before Update is called in the first frame.
//
// If Layout returns non-positive numbers, the caller can panic.
//
// You can return a fixed screen size if you don't care, or you can also return a calculated screen size
// adjusted with the given outside size.
Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeight int)
}
// DefaultTPS represents a default ticks per second, that represents how many times game updating happens in a second.
const DefaultTPS = 60
// CurrentFPS returns the current number of FPS (frames per second), that represents
// how many swapping buffer happens per second.
//
// On some environments, CurrentFPS doesn't return a reliable value since vsync doesn't work well there.
// If you want to measure the application's speed, Use CurrentTPS.
//
// This value is for measurement and/or debug, and your game logic should not rely on this value.
//
// CurrentFPS is concurrent-safe.
func CurrentFPS() float64 {
return clock.CurrentFPS()
}
var (
isScreenClearedEveryFrame = int32(1)
isRunGameEnded_ = int32(0)
currentMaxTPS = int32(DefaultTPS)
)
// SetScreenClearedEveryFrame enables or disables the clearing of the screen at the beginning of each frame.
// The default value is true and the screen is cleared each frame by default.
//
// SetScreenClearedEveryFrame is concurrent-safe.
func SetScreenClearedEveryFrame(cleared bool) {
v := int32(0)
if cleared {
v = 1
}
atomic.StoreInt32(&isScreenClearedEveryFrame, v)
theUIContext.setScreenClearedEveryFrame(cleared)
}
// IsScreenClearedEveryFrame returns true if the frame isn't cleared at the beginning.
//
// IsScreenClearedEveryFrame is concurrent-safe.
func IsScreenClearedEveryFrame() bool {
return atomic.LoadInt32(&isScreenClearedEveryFrame) != 0
}
type imageDumperGame struct {
game Game
d *imageDumper
err error
}
func (i *imageDumperGame) Update() error {
if i.err != nil {
return i.err
}
if i.d == nil {
i.d = &imageDumper{g: i.game}
}
return i.d.update()
}
func (i *imageDumperGame) Draw(screen *Image) {
if i.err != nil {
return
}
i.game.Draw(screen)
i.err = i.d.dump(screen)
}
func (i *imageDumperGame) Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeight int) {
return i.game.Layout(outsideWidth, outsideHeight)
}
// RunGame starts the main loop and runs the game.
// game's Update function is called every tick to update the game logic.
// game's Draw function is called every frame to draw the screen.
// game's Layout function is called when necessary, and you can specify the logical screen size by the function.
//
// game's functions are called on the same goroutine.
//
// On browsers, it is strongly recommended to use iframe if you embed an Ebiten application in your website.
//
// RunGame must be called on the main thread.
// Note that Ebiten bounds the main goroutine to the main OS thread by runtime.LockOSThread.
//
// Ebiten tries to call game's Update function 60 times a second by default. In other words,
// TPS (ticks per second) is 60 by default.
// This is not related to framerate (display's refresh rate).
//
// RunGame returns error when 1) error happens in the underlying graphics driver, 2) audio error happens or
// 3) f returns error. In the case of 3), RunGame returns the same error.
//
// The size unit is device-independent pixel.
//
// Don't call RunGame twice or more in one process.
func RunGame(game Game) error {
defer atomic.StoreInt32(&isRunGameEnded_, 1)
initializeWindowPositionIfNeeded(WindowSize())
theUIContext.set(&imageDumperGame{
game: game,
})
if err := ui.Get().Run(theUIContext); err != nil {
if err == ui.RegularTermination {
return nil
}
return err
}
return nil
}
// RunOnMainThread calls the given f on the main thread, and blocks until f returns.
func RunOnMainThread(f func()) {
graphicscommand.RunOnMainThread(f)
}
func isRunGameEnded() bool {
return atomic.LoadInt32(&isRunGameEnded_) != 0
}
// ScreenSizeInFullscreen returns the size in device-independent pixels when the game is fullscreen.
// The adopted monitor is the 'current' monitor which the window belongs to.
// The returned value can be given to Run or SetSize function if the perfectly fit fullscreen is needed.
//
// On browsers, ScreenSizeInFullscreen returns the 'window' (global object) size, not 'screen' size since an Ebiten
// game should not know the outside of the window object.
//
// On mobiles, ScreenSizeInFullscreen returns (0, 0) so far.
//
// ScreenSizeInFullscreen's use cases are limited. If you are making a fullscreen application, you can use RunGame and
// the Game interface's Layout function instead. If you are making a not-fullscreen application but the application's
// behavior depends on the monitor size, ScreenSizeInFullscreen is useful.
//
// ScreenSizeInFullscreen must be called on the main thread before ebiten.Run, and is concurrent-safe after
// ebiten.Run.
func ScreenSizeInFullscreen() (int, int) {
return ui.Get().ScreenSizeInFullscreen()
}
// CursorMode returns the current cursor mode.
//
// CursorMode returns CursorModeHidden on mobiles.
//
// CursorMode is concurrent-safe.
func CursorMode() CursorModeType {
return ui.Get().CursorMode()
}
// SetCursorMode sets the render and capture mode of the mouse cursor.
// CursorModeVisible sets the cursor to always be visible.
// CursorModeHidden hides the system cursor when over the window.
// CursorModeCaptured hides the system cursor and locks it to the window.
//
// CursorModeCaptured also works on browsers.
// When the user exits the captured mode not by SetCursorMode but by the UI (e.g., pressing ESC),
// the previous cursor mode is set automatically.
//
// SetCursorMode does nothing on mobiles.
//
// SetCursorMode is concurrent-safe.
func SetCursorMode(mode CursorModeType) {
ui.Get().SetCursorMode(mode)
}
// CursorShape returns the current cursor shape.
//
// CursorShape returns CursorShapeDefault on mobiles.
//
// CursorShape is concurrent-safe.
func CursorShape() CursorShapeType {
return ui.Get().CursorShape()
}
// SetCursorShape sets the cursor shape.
//
// SetCursorShape is concurrent-safe.
func SetCursorShape(shape CursorShapeType) {
ui.Get().SetCursorShape(shape)
}
// IsFullscreen reports whether the current mode is fullscreen or not.
//
// IsFullscreen always returns false on mobiles.
//
// IsFullscreen is concurrent-safe.
func IsFullscreen() bool {
return ui.Get().IsFullscreen()
}
// SetFullscreen changes the current mode to fullscreen or not on desktops and browsers.
//
// In fullscreen mode, the game screen is automatically enlarged
// to fit with the monitor. The current scale value is ignored.
//
// On desktops, Ebiten uses 'windowed' fullscreen mode, which doesn't change
// your monitor's resolution.
//
// On browsers, triggering fullscreen requires a user gesture otherwise SetFullscreen does nothing but leave an error message in console.
// This behaviour varies across browser implementations, your mileage may vary.
//
// SetFullscreen does nothing on mobiles.
//
// SetFullscreen does nothing on macOS when the window is fullscreened natively by the macOS desktop
// instead of SetFullscreen(true).
//
// SetFullscreen is concurrent-safe.
func SetFullscreen(fullscreen bool) {
ui.Get().SetFullscreen(fullscreen)
}
// IsFocused returns a boolean value indicating whether
// the game is in focus or in the foreground.
//
// IsFocused will only return true if IsRunnableOnUnfocused is false.
//
// IsFocused is concurrent-safe.
func IsFocused() bool {
return ui.Get().IsFocused()
}
// IsRunnableOnUnfocused returns a boolean value indicating whether
// the game runs even in background.
//
// IsRunnableOnUnfocused is concurrent-safe.
func IsRunnableOnUnfocused() bool {
return ui.Get().IsRunnableOnUnfocused()
}
// SetRunnableOnUnfocused sets the state if the game runs even in background.
//
// If the given value is true, the game runs even in background e.g. when losing focus.
// The initial state is true.
//
// Known issue: On browsers, even if the state is on, the game doesn't run in background tabs.
// This is because browsers throttles background tabs not to often update.
//
// SetRunnableOnUnfocused does nothing on mobiles so far.
//
// SetRunnableOnUnfocused is concurrent-safe.
func SetRunnableOnUnfocused(runnableOnUnfocused bool) {
ui.Get().SetRunnableOnUnfocused(runnableOnUnfocused)
}
// DeviceScaleFactor returns a device scale factor value of the current monitor which the window belongs to.
//
// DeviceScaleFactor returns a meaningful value on high-DPI display environment,
// otherwise DeviceScaleFactor returns 1.
//
// DeviceScaleFactor might panic on init function on some devices like Android.
// Then, it is not recommended to call DeviceScaleFactor from init functions.
//
// DeviceScaleFactor must be called on the main thread before the main loop, and is concurrent-safe after the main
// loop.
//
// DeviceScaleFactor is concurrent-safe.
//
// BUG: DeviceScaleFactor value is not affected by SetWindowPosition before RunGame (#1575).
func DeviceScaleFactor() float64 {
return ui.Get().DeviceScaleFactor()
}
// IsVsyncEnabled returns a boolean value indicating whether
// the game uses the display's vsync.
//
// Deprecated: as of v2.2. Use FPSMode instead.
func IsVsyncEnabled() bool {
return ui.Get().FPSMode() == ui.FPSModeVsyncOn
}
// SetVsyncEnabled sets a boolean value indicating whether
// the game uses the display's vsync.
//
// Deprecated: as of v2.2. Use SetFPSMode instead.
func SetVsyncEnabled(enabled bool) {
if enabled {
ui.Get().SetFPSMode(ui.FPSModeVsyncOn)
} else {
ui.Get().SetFPSMode(ui.FPSModeVsyncOffMaximum)
}
}
// FPSModeType is a type of FPS modes.
type FPSModeType = ui.FPSMode
const (
// FPSModeVsyncOn indicates that the game tries to sync the display's refresh rate.
// FPSModeVsyncOn is the default mode.
FPSModeVsyncOn FPSModeType = ui.FPSModeVsyncOn
// FPSModeVsyncOffMaximum indicates that the game doesn't sync with vsync, and
// the game is updated whenever possible.
//
// Be careful that FPSModeVsyncOffMaximum might consume a lot of battery power.
//
// In FPSModeVsyncOffMaximum, the game's Draw is called almost without sleeping.
// The game's Update is called based on the specified TPS.
FPSModeVsyncOffMaximum FPSModeType = ui.FPSModeVsyncOffMaximum
// FPSModeVsyncOffMinimum indicates that the game doesn't sync with vsync, and
// the game is updated only when necessary.
//
// FPSModeVsyncOffMinimum is useful for relatively static applications to save battery power.
//
// In FPSModeVsyncOffMinimum, the game's Update and Draw are called only when
// 1) new inputting except for gamepads is detected, or 2) ScheduleFrame is called.
// In FPSModeVsyncOffMinimum, TPS is SyncWithFPS no matter what TPS is specified at SetMaxTPS.
FPSModeVsyncOffMinimum FPSModeType = ui.FPSModeVsyncOffMinimum
)
// FPSMode returns the current FPS mode.
//
// FPSMode is concurrent-safe.
func FPSMode() FPSModeType {
return ui.Get().FPSMode()
}
// SetFPSMode sets the FPS mode.
// The default FPS mode is FPSModeVsyncOn.
//
// SetFPSMode is concurrent-safe.
func SetFPSMode(mode FPSModeType) {
ui.Get().SetFPSMode(mode)
}
// ScheduleFrame schedules a next frame when the current FPS mode is FPSModeVsyncOffMinimum.
//
// ScheduleFrame is concurrent-safe.
func ScheduleFrame() {
ui.Get().ScheduleFrame()
}
// MaxTPS returns the current maximum TPS.
//
// MaxTPS is concurrent-safe.
func MaxTPS() int {
if FPSMode() == FPSModeVsyncOffMinimum {
return SyncWithFPS
}
return int(atomic.LoadInt32(&currentMaxTPS))
}
// CurrentTPS returns the current TPS (ticks per second),
// that represents how many update function is called in a second.
//
// This value is for measurement and/or debug, and your game logic should not rely on this value.
//
// CurrentTPS is concurrent-safe.
func CurrentTPS() float64 {
return clock.CurrentTPS()
}
// SyncWithFPS is a special TPS value that means TPS syncs with FPS.
const SyncWithFPS = clock.SyncWithFPS
// UncappedTPS is a special TPS value that means TPS syncs with FPS.
//
// Deprecated: as of v2.2. Use SyncWithFPS instead.
const UncappedTPS = SyncWithFPS
// SetMaxTPS sets the maximum TPS (ticks per second),
// that represents how many updating function is called per second.
// The initial value is 60.
//
// If tps is SyncWithFPS, TPS is uncapped and the game is updated per frame.
// If tps is negative but not SyncWithFPS, SetMaxTPS panics.
//
// SetMaxTPS is concurrent-safe.
func SetMaxTPS(tps int) {
if tps < 0 && tps != SyncWithFPS {
panic("ebiten: tps must be >= 0 or SyncWithFPS")
}
atomic.StoreInt32(&currentMaxTPS, int32(tps))
}
// IsScreenTransparent reports whether the window is transparent.
//
// IsScreenTransparent is concurrent-safe.
func IsScreenTransparent() bool {
return ui.Get().IsScreenTransparent()
}
// SetScreenTransparent sets the state if the window is transparent.
//
// SetScreenTransparent panics if SetScreenTransparent is called after the main loop.
//
// SetScreenTransparent does nothing on mobiles.
//
// SetScreenTransparent is concurrent-safe.
func SetScreenTransparent(transparent bool) {
ui.Get().SetScreenTransparent(transparent)
}
// SetInitFocused sets whether the application is focused on show.
// The default value is true, i.e., the application is focused.
// Note that the application does not proceed if this is not focused by default.
// This behavior can be changed by SetRunnableOnUnfocused.
//
// SetInitFocused does nothing on mobile.
//
// SetInitFocused panics if this is called after the main loop.
//
// SetInitFocused is cuncurrent-safe.
func SetInitFocused(focused bool) {
ui.Get().SetInitFocused(focused)
}