mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-11-10 13:07:26 +01:00
121 lines
3.4 KiB
Go
121 lines
3.4 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 opengl
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"github.com/go-gl/gl"
|
|
"github.com/hajimehoshi/ebiten/internal"
|
|
"image"
|
|
"image/draw"
|
|
)
|
|
|
|
func adjustImageForTexture(img image.Image) *image.RGBA {
|
|
width, height := img.Bounds().Size().X, img.Bounds().Size().Y
|
|
adjustedImageBounds := image.Rectangle{
|
|
image.ZP,
|
|
image.Point{
|
|
internal.NextPowerOf2Int(width),
|
|
internal.NextPowerOf2Int(height),
|
|
},
|
|
}
|
|
if nrgba, ok := img.(*image.RGBA); ok && img.Bounds() == adjustedImageBounds {
|
|
return nrgba
|
|
}
|
|
|
|
adjustedImage := image.NewRGBA(adjustedImageBounds)
|
|
dstBounds := image.Rectangle{
|
|
image.ZP,
|
|
img.Bounds().Size(),
|
|
}
|
|
draw.Draw(adjustedImage, dstBounds, img, image.ZP, draw.Src)
|
|
return adjustedImage
|
|
}
|
|
|
|
type Texture struct {
|
|
native gl.Texture
|
|
width int
|
|
height int
|
|
}
|
|
|
|
func (t *Texture) Native() gl.Texture {
|
|
return t.native
|
|
}
|
|
|
|
func (t *Texture) Size() (width, height int) {
|
|
return t.width, t.height
|
|
}
|
|
|
|
func createNativeTexture(textureWidth, textureHeight int, pixels []uint8, filter Filter) gl.Texture {
|
|
nativeTexture := gl.GenTexture()
|
|
if nativeTexture < 0 {
|
|
panic("glGenTexture failed")
|
|
}
|
|
gl.PixelStorei(gl.UNPACK_ALIGNMENT, 4)
|
|
nativeTexture.Bind(gl.TEXTURE_2D)
|
|
defer gl.Texture(0).Bind(gl.TEXTURE_2D)
|
|
|
|
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, int(filter))
|
|
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, int(filter))
|
|
|
|
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, textureWidth, textureHeight, 0, gl.RGBA, gl.UNSIGNED_BYTE, pixels)
|
|
|
|
return nativeTexture
|
|
}
|
|
|
|
func NewTexture(width, height int, filter Filter) (*Texture, error) {
|
|
w := internal.NextPowerOf2Int(width)
|
|
h := internal.NextPowerOf2Int(height)
|
|
if w < 4 {
|
|
return nil, errors.New("width must be equal or more than 4.")
|
|
}
|
|
if h < 4 {
|
|
return nil, errors.New("height must be equal or more than 4.")
|
|
}
|
|
native := createNativeTexture(w, h, nil, filter)
|
|
return &Texture{native, width, height}, nil
|
|
}
|
|
|
|
func NewTextureFromImage(img image.Image, filter Filter) (*Texture, error) {
|
|
origSize := img.Bounds().Size()
|
|
if origSize.X < 4 {
|
|
return nil, errors.New("width must be equal or more than 4.")
|
|
}
|
|
if origSize.Y < 4 {
|
|
return nil, errors.New("height must be equal or more than 4.")
|
|
}
|
|
adjustedImage := adjustImageForTexture(img)
|
|
size := adjustedImage.Bounds().Size()
|
|
native := createNativeTexture(size.X, size.Y, adjustedImage.Pix, filter)
|
|
return &Texture{native, origSize.X, origSize.Y}, nil
|
|
}
|
|
|
|
func (t *Texture) Dispose() {
|
|
t.native.Delete()
|
|
}
|
|
|
|
func (t *Texture) Pixels() ([]uint8, error) {
|
|
w, h := internal.NextPowerOf2Int(t.width), internal.NextPowerOf2Int(t.height)
|
|
pixels := make([]uint8, 4*w*h)
|
|
t.native.Bind(gl.TEXTURE_2D)
|
|
gl.GetTexImage(gl.TEXTURE_2D, 0, gl.RGBA, gl.UNSIGNED_BYTE, pixels)
|
|
if e := gl.GetError(); e != gl.NO_ERROR {
|
|
// TODO: Use glu.ErrorString
|
|
return nil, errors.New(fmt.Sprintf("gl error: %d", e))
|
|
}
|
|
return pixels, nil
|
|
}
|