mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-09-20 13:22:19 +02:00
79 lines
2.0 KiB
Go
79 lines
2.0 KiB
Go
// Copyright 2018 The Ebiten 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.
|
|
|
|
package graphics
|
|
|
|
type CompositeMode int
|
|
|
|
const (
|
|
CompositeModeSourceOver CompositeMode = iota // This value must be 0 (= initial value)
|
|
CompositeModeClear
|
|
CompositeModeCopy
|
|
CompositeModeDestination
|
|
CompositeModeDestinationOver
|
|
CompositeModeSourceIn
|
|
CompositeModeDestinationIn
|
|
CompositeModeSourceOut
|
|
CompositeModeDestinationOut
|
|
CompositeModeSourceAtop
|
|
CompositeModeDestinationAtop
|
|
CompositeModeXor
|
|
CompositeModeLighter
|
|
CompositeModeUnknown
|
|
)
|
|
|
|
type Operation int
|
|
|
|
const (
|
|
Zero Operation = iota
|
|
One
|
|
SrcAlpha
|
|
DstAlpha
|
|
OneMinusSrcAlpha
|
|
OneMinusDstAlpha
|
|
)
|
|
|
|
func (c CompositeMode) Operations() (src Operation, dst Operation) {
|
|
switch c {
|
|
case CompositeModeSourceOver:
|
|
return One, OneMinusSrcAlpha
|
|
case CompositeModeClear:
|
|
return Zero, Zero
|
|
case CompositeModeCopy:
|
|
return One, Zero
|
|
case CompositeModeDestination:
|
|
return Zero, One
|
|
case CompositeModeDestinationOver:
|
|
return OneMinusDstAlpha, One
|
|
case CompositeModeSourceIn:
|
|
return DstAlpha, Zero
|
|
case CompositeModeDestinationIn:
|
|
return Zero, SrcAlpha
|
|
case CompositeModeSourceOut:
|
|
return OneMinusDstAlpha, Zero
|
|
case CompositeModeDestinationOut:
|
|
return Zero, OneMinusSrcAlpha
|
|
case CompositeModeSourceAtop:
|
|
return DstAlpha, OneMinusSrcAlpha
|
|
case CompositeModeDestinationAtop:
|
|
return OneMinusDstAlpha, SrcAlpha
|
|
case CompositeModeXor:
|
|
return OneMinusDstAlpha, OneMinusSrcAlpha
|
|
case CompositeModeLighter:
|
|
return One, One
|
|
default:
|
|
panic("not reached")
|
|
}
|
|
}
|