mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-09-20 13:22:19 +02:00
94 lines
2.0 KiB
Go
94 lines
2.0 KiB
Go
package opengl
|
|
|
|
// #cgo LDFLAGS: -framework OpenGL
|
|
//
|
|
// #include <OpenGL/gl.h>
|
|
import "C"
|
|
import (
|
|
"image"
|
|
"unsafe"
|
|
)
|
|
|
|
func Clp2(x uint64) uint64 {
|
|
x -= 1
|
|
x |= (x >> 1)
|
|
x |= (x >> 2)
|
|
x |= (x >> 4)
|
|
x |= (x >> 8)
|
|
x |= (x >> 16)
|
|
x |= (x >> 32)
|
|
return x + 1
|
|
}
|
|
|
|
type Texture struct {
|
|
id C.GLuint
|
|
width int
|
|
height int
|
|
textureWidth int
|
|
textureHeight int
|
|
isDirty bool
|
|
}
|
|
|
|
func createTexture(width, height int, pixels []uint8) *Texture {
|
|
textureWidth := int(Clp2(uint64(width)))
|
|
textureHeight := int(Clp2(uint64(height)))
|
|
if pixels != nil {
|
|
if width != textureWidth {
|
|
panic("sorry, but width should be power of 2")
|
|
}
|
|
if height != textureHeight {
|
|
panic("sorry, but height should be power of 2")
|
|
}
|
|
}
|
|
texture := &Texture{
|
|
id: 0,
|
|
width: width,
|
|
height: height,
|
|
textureWidth: textureWidth,
|
|
textureHeight: textureHeight,
|
|
}
|
|
|
|
textureID := C.GLuint(0)
|
|
C.glGenTextures(1, (*C.GLuint)(&textureID))
|
|
if textureID == 0 {
|
|
panic("glGenTexture failed")
|
|
}
|
|
C.glPixelStorei(C.GL_UNPACK_ALIGNMENT, 4)
|
|
C.glBindTexture(C.GL_TEXTURE_2D, C.GLuint(textureID))
|
|
|
|
ptr := unsafe.Pointer(nil)
|
|
if pixels != nil {
|
|
ptr = unsafe.Pointer(&pixels[0])
|
|
}
|
|
C.glTexImage2D(C.GL_TEXTURE_2D, 0, C.GL_RGBA,
|
|
C.GLsizei(textureWidth), C.GLsizei(textureHeight),
|
|
0, C.GL_RGBA, C.GL_UNSIGNED_BYTE, ptr)
|
|
|
|
C.glTexParameteri(C.GL_TEXTURE_2D, C.GL_TEXTURE_MAG_FILTER, C.GL_LINEAR)
|
|
C.glTexParameteri(C.GL_TEXTURE_2D, C.GL_TEXTURE_MIN_FILTER, C.GL_LINEAR)
|
|
C.glBindTexture(C.GL_TEXTURE_2D, 0)
|
|
|
|
texture.id = textureID
|
|
texture.isDirty = pixels == nil
|
|
|
|
return texture
|
|
}
|
|
|
|
func newTexture(width, height int) *Texture {
|
|
return createTexture(width, height, nil)
|
|
}
|
|
|
|
func newTextureFromImage(img image.Image) *Texture {
|
|
var pix []uint8
|
|
switch img.(type) {
|
|
case *image.RGBA:
|
|
pix = img.(*image.RGBA).Pix
|
|
case *image.NRGBA:
|
|
pix = img.(*image.NRGBA).Pix
|
|
default:
|
|
panic("image should be RGBA or NRGBA")
|
|
}
|
|
size := img.Bounds().Size()
|
|
return createTexture(size.X, size.Y, pix)
|
|
}
|