ebiten/uicontext.go

363 lines
9.0 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 (
"fmt"
"math"
"sync"
"sync/atomic"
"github.com/hajimehoshi/ebiten/internal/buffered"
"github.com/hajimehoshi/ebiten/internal/clock"
"github.com/hajimehoshi/ebiten/internal/driver"
"github.com/hajimehoshi/ebiten/internal/hooks"
)
type defaultGame struct {
update func(screen *Image) error
width int
height int
context *uiContext
}
func (d *defaultGame) Update(screen *Image) error {
return d.update(screen)
}
func (d *defaultGame) Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeight int) {
// Ignore the outside size.
d.context.m.Lock()
w, h := d.width, d.height
d.context.m.Unlock()
return w, h
}
type uiContext struct {
game Game
offscreen *Image
screen *Image
updateCalled bool
// scaleForWindow is the scale of a window. This doesn't represent the scale on fullscreen. This value works
// only on desktops.
//
// scaleForWindow is for backward compatibility and is used to calculate the window size when SetScreenSize
// is called.
scaleForWindow float64
outsideSizeUpdated bool
outsideWidth float64
outsideHeight float64
err atomic.Value
m sync.Mutex
}
var theUIContext = &uiContext{}
func (c *uiContext) set(game Game, scaleForWindow float64) {
c.m.Lock()
defer c.m.Unlock()
c.game = game
if g, ok := game.(*defaultGame); ok {
c.scaleForWindow = scaleForWindow
g.context = c
}
}
func (c *uiContext) setError(err error) {
c.err.Store(err)
}
func (c *uiContext) setScaleForWindow(scale float64) {
c.m.Lock()
defer c.m.Unlock()
if c.game == nil {
panic("ebiten: setScaleForWindow can be called only after the main loop starts")
}
g, ok := c.game.(*defaultGame)
if !ok {
panic("ebiten: setScaleForWindow can be called only when Run is used")
}
if w := uiDriver().Window(); w != nil {
ww, wh := g.width, g.height
c.scaleForWindow = scale
w.SetSize(int(float64(ww)*scale), int(float64(wh)*scale))
}
}
func (c *uiContext) getScaleForWindow() float64 {
c.m.Lock()
defer c.m.Unlock()
if c.game == nil {
panic("ebiten: getScaleForWindow can be called only after the main loop starts")
}
if _, ok := c.game.(*defaultGame); !ok {
panic("ebiten: getScaleForWindow can be called only when Run is used")
}
s := c.scaleForWindow
return s
}
// setScreenSize sets the (logical) screen size and adjusts the window size.
//
// setScreenSize is for backward compatibility. This is called from ebiten.SetScreenSize.
func (c *uiContext) setScreenSize(width, height int) {
c.m.Lock()
defer c.m.Unlock()
if c.game == nil {
panic("ebiten: SetScreenSize can be called only after the main loop starts")
}
g, ok := c.game.(*defaultGame)
if !ok {
panic("ebiten: SetScreenSize can be called only when Run is used")
}
g.width = width
g.height = height
if w := uiDriver().Window(); w != nil {
s := c.scaleForWindow
w.SetSize(int(float64(width)*s), int(float64(height)*s))
}
}
func (c *uiContext) Layout(outsideWidth, outsideHeight float64) {
c.outsideSizeUpdated = true
c.outsideWidth = outsideWidth
c.outsideHeight = outsideHeight
}
func (c *uiContext) updateOffscreen() {
sw, sh := c.game.Layout(int(c.outsideWidth), int(c.outsideHeight))
if sw <= 0 || sh <= 0 {
panic("ebiten: Layout must return positive numbers")
}
if c.offscreen != nil && !c.outsideSizeUpdated {
if w, h := c.offscreen.Size(); w == sw && h == sh {
return
}
}
c.outsideSizeUpdated = false
if c.screen != nil {
_ = c.screen.Dispose()
c.screen = nil
}
if c.offscreen != nil {
if w, h := c.offscreen.Size(); w != sw || h != sh {
_ = c.offscreen.Dispose()
c.offscreen = nil
}
}
if c.offscreen == nil {
c.offscreen = newImage(sw, sh, FilterDefault)
c.offscreen.mipmap.SetVolatile(!IsClearingScreenSkipped())
}
// The window size is automatically adjusted when Run is used.
if _, ok := c.game.(*defaultGame); ok {
c.setScreenSize(sw, sh)
}
// TODO: This is duplicated with mobile/ebitenmobileview/funcs.go. Refactor this.
d := uiDriver().DeviceScaleFactor()
c.screen = newScreenFramebufferImage(int(c.outsideWidth*d), int(c.outsideHeight*d))
// Do not have to update scaleForWindow since this is used only for backward compatibility.
// Then, if a window is resizable, scaleForWindow (= ebiten.ScreenScale) might not match with the actual
// scale. This is fine since ebiten.ScreenScale will be deprecated.
}
func (c *uiContext) setClearingScreenSkipped(skipped bool) {
c.m.Lock()
defer c.m.Unlock()
if c.offscreen != nil {
c.offscreen.mipmap.SetVolatile(!skipped)
}
}
func (c *uiContext) setWindowResizable(resizable bool) {
c.m.Lock()
defer c.m.Unlock()
if resizable && c.game != nil {
if _, ok := c.game.(*defaultGame); ok {
panic("ebiten: a resizable window works with RunGame, not Run")
}
}
if w := uiDriver().Window(); w != nil {
w.SetResizable(resizable)
}
}
func (c *uiContext) screenScale() float64 {
if c.offscreen == nil {
return 0
}
sw, sh := c.offscreen.Size()
d := uiDriver().DeviceScaleFactor()
scaleX := c.outsideWidth / float64(sw) * d
scaleY := c.outsideHeight / float64(sh) * d
return math.Min(scaleX, scaleY)
}
func (c *uiContext) offsets() (float64, float64) {
if c.offscreen == nil {
return 0, 0
}
sw, sh := c.offscreen.Size()
d := uiDriver().DeviceScaleFactor()
s := c.screenScale()
width := float64(sw) * s
height := float64(sh) * s
return (c.outsideWidth*d - width) / 2, (c.outsideHeight*d - height) / 2
}
func (c *uiContext) Update() error {
// TODO: If updateCount is 0 and vsync is disabled, swapping buffers can be skipped.
if err, ok := c.err.Load().(error); ok && err != nil {
return err
}
if err := buffered.BeginFrame(); err != nil {
return err
}
if err := c.update(); err != nil {
return err
}
if err := buffered.EndFrame(); err != nil {
return err
}
return nil
}
func (c *uiContext) Draw() error {
if err, ok := c.err.Load().(error); ok && err != nil {
return err
}
if err := buffered.BeginFrame(); err != nil {
return err
}
c.draw()
if err := buffered.EndFrame(); err != nil {
return err
}
return nil
}
func (c *uiContext) update() error {
_, hasDraw := c.game.(interface{ Draw(*Image) })
updateCount := clock.Update(MaxTPS())
// Ensure that Update is called once before Draw so that Update can be used for initialization.
if !c.updateCalled && updateCount == 0 {
updateCount = 1
c.updateCalled = true
}
for i := 0; i < updateCount; i++ {
c.updateOffscreen()
// When the game's Draw exists, rendering should be always skipped.
//
// When the game's Draw does not exist, the last Update call should process drawing.
// This assumes that (*uiContext).Update and (*uiContext).Draw are called successively.
//
// TODO: Make (Game).Draw mandatory and remove this assumption when we can update the major version.
// Move the clock usage to the UI driver side.
setDrawingSkipped(hasDraw || i < updateCount-1)
if err := hooks.RunBeforeUpdateHooks(); err != nil {
return err
}
// Multiple successive Clear call should be integrated into one graphics command, then
// calling Clear on every Update should not affect the performance.
if !IsClearingScreenSkipped() {
c.offscreen.Clear()
}
if err := c.game.Update(c.offscreen); err != nil {
return err
}
uiDriver().ResetForFrame()
}
return nil
}
func (c *uiContext) draw() {
// c.screen might be nil when updateCount is 0 in the initial state (#1039).
if c.screen == nil {
return
}
if game, ok := c.game.(interface{ Draw(*Image) }); ok {
if !IsClearingScreenSkipped() {
c.offscreen.Clear()
}
game.Draw(c.offscreen)
}
// This clear is needed for fullscreen mode or some mobile platforms (#622).
c.screen.Clear()
op := &DrawImageOptions{}
s := c.screenScale()
switch vd := uiDriver().Graphics().FramebufferYDirection(); vd {
case driver.Upward:
op.GeoM.Scale(s, -s)
_, h := c.offscreen.Size()
op.GeoM.Translate(0, float64(h)*s)
case driver.Downward:
op.GeoM.Scale(s, s)
default:
panic(fmt.Sprintf("ebiten: invalid v-direction: %d", vd))
}
op.GeoM.Translate(c.offsets())
op.CompositeMode = CompositeModeCopy
// filterScreen works with >=1 scale, but does not well with <1 scale.
// Use regular FilterLinear instead so far (#669).
if s >= 1 {
op.Filter = filterScreen
} else {
op.Filter = FilterLinear
}
_ = c.screen.DrawImage(c.offscreen, op)
}
func (c *uiContext) AdjustPosition(x, y float64) (float64, float64) {
d := uiDriver().DeviceScaleFactor()
ox, oy := c.offsets()
s := c.screenScale()
return (x*d - ox) / s, (y*d - oy) / s
}