mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-12-27 12:18:55 +01:00
76 lines
1.9 KiB
Go
76 lines
1.9 KiB
Go
// Copyright 2017 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
|
|
|
|
import (
|
|
"image"
|
|
"image/color"
|
|
"image/draw"
|
|
)
|
|
|
|
// CopyImage copies img to a new RGBA image.
|
|
//
|
|
// Basically CopyImage just calls draw.Draw.
|
|
// If img is a paletted image, an optimized copying method is used.
|
|
//
|
|
// CopyImage is used only internally but it is exposed for testing.
|
|
func CopyImage(img image.Image) []byte {
|
|
size := img.Bounds().Size()
|
|
w, h := size.X, size.Y
|
|
bs := make([]byte, 4*w*h)
|
|
|
|
switch img := img.(type) {
|
|
case *image.Paletted:
|
|
b := img.Bounds()
|
|
x0 := b.Min.X
|
|
y0 := b.Min.Y
|
|
x1 := b.Max.X
|
|
y1 := b.Max.Y
|
|
|
|
palette := make([]uint8, len(img.Palette)*4)
|
|
for i, c := range img.Palette {
|
|
rgba := color.RGBAModel.Convert(c).(color.RGBA)
|
|
palette[4*i] = rgba.R
|
|
palette[4*i+1] = rgba.G
|
|
palette[4*i+2] = rgba.B
|
|
palette[4*i+3] = rgba.A
|
|
}
|
|
// Even img is a subimage of another image, Pix starts with 0-th index.
|
|
idx0 := 0
|
|
idx1 := 0
|
|
d := img.Stride - (x1 - x0)
|
|
for j := 0; j < y1-y0; j++ {
|
|
for i := 0; i < x1-x0; i++ {
|
|
p := int(img.Pix[idx0])
|
|
bs[idx1] = palette[4*p]
|
|
bs[idx1+1] = palette[4*p+1]
|
|
bs[idx1+2] = palette[4*p+2]
|
|
bs[idx1+3] = palette[4*p+3]
|
|
idx0++
|
|
idx1 += 4
|
|
}
|
|
idx0 += d
|
|
}
|
|
default:
|
|
dstImg := &image.RGBA{
|
|
Pix: bs,
|
|
Stride: 4 * w,
|
|
Rect: image.Rect(0, 0, w, h),
|
|
}
|
|
draw.Draw(dstImg, image.Rect(0, 0, w, h), img, img.Bounds().Min, draw.Src)
|
|
}
|
|
return bs
|
|
}
|