func uploadTexture_NRGBA32(img *image.NRGBA) gl.Texture {
b := img.Bounds()
data := make([]uint8, b.Max.X*b.Max.Y*4)
for y := 0; y < b.Max.Y; y++ {
for x := 0; x < b.Max.X; x++ {
p := &img.Pix[y*img.Stride+x]
offset := y*b.Max.X*4 + x*4
data[offset+0] = p.R
data[offset+1] = p.G
data[offset+2] = p.B
data[offset+3] = p.A
}
}
id := gl.GenTexture()
id.Bind(gl.TEXTURE_2D)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_R, gl.CLAMP_TO_EDGE)
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, b.Max.X, b.Max.Y, 0, gl.RGBA, data)
if gl.GetError() != gl.NO_ERROR {
id.Delete()
panic(os.NewError("Failed to load a texture"))
return 0
}
return id
}
// Load bitmap from path as GL texture
func LoadGLTexture(path string) {
image := sdl.Load(path)
if image == nil {
panic(sdl.GetError())
}
// Check that the image's width is a power of 2
if image.W&(image.W-1) != 0 {
fmt.Println("warning:", path, "has a width that is not a power of 2")
}
// Also check if the height is a power of 2
if image.H&(image.H-1) != 0 {
fmt.Println("warning:", path, "has an height that is not a power of 2")
}
// get the number of channels in the SDL surface
nOfColors := image.Format.BytesPerPixel
var textureFormat gl.GLenum
if nOfColors == 4 { // contains alpha channel
if image.Format.Rmask == 0x000000ff {
textureFormat = gl.RGBA
} else {
textureFormat = gl.BGRA
}
} else if nOfColors == 3 { // no alpha channel
if image.Format.Rmask == 0x000000ff {
textureFormat = gl.RGB
} else {
textureFormat = gl.BGR
}
} else {
fmt.Println("warning:", path, "is not truecolor, this will probably break")
}
texture = gl.GenTexture()
// Typical texture generation using data from the bitmap
gl.BindTexture(gl.TEXTURE_2D, uint(texture))
// Generate the texture
gl.TexImage2D(gl.TEXTURE_2D, 0, int(image.Format.BytesPerPixel),
int(image.W), int(image.H),
0, textureFormat, gl.UNSIGNED_BYTE, image.Pixels,
)
// linear filtering
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
// free up memory we have used.
image.Free()
}
func (gd *openGLGraphicsDevice) NewTexture2D(img image.Image) Texture2D {
rect := img.Bounds()
width, height := rect.Max.X-rect.Min.X, rect.Max.Y-rect.Min.Y
id := gl.GenTexture()
id.Bind(gl.TEXTURE_2D)
gl.TexParameterf(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
gl.TexParameterf(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
switch i := img.(type) {
case *image.RGBA:
gl.TexImage2D(gl.TEXTURE_2D, 0, 4, width, height, 0, gl.RGBA, &i.Pix[0].R)
//fmt.Println("teximg2d", i.Pix[0:4], i.Stride, width, height, gl.GetError(), id)
default:
panic("unknown format")
}
return &openGLTexture2D{id}
}
func uploadTexture_RGBA32(w, h int, data []byte) gl.Texture {
id := gl.GenTexture()
id.Bind(gl.TEXTURE_2D)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_R, gl.CLAMP_TO_EDGE)
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, int(w), int(h), 0, gl.RGBA, data)
if gl.GetError() != gl.NO_ERROR {
id.Delete()
panic("Failed to load a texture")
return 0
}
return id
}
func loadSurface(img image.Image) gl.Texture {
w := img.Bounds().Dx()
h := img.Bounds().Dy()
rgba := image.NewRGBA(w, h)
for x := 0; x < w; x++ {
for y := 0; y < h; y++ {
rgba.Set(x, y, img.At(x, y))
}
}
gl.ActiveTexture(gl.TEXTURE0)
texture := gl.GenTexture()
texture.Bind(gl.TEXTURE_2D)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, rgba.Rect.Dx(), rgba.Rect.Dy(), 0, gl.RGBA, gl.UNSIGNED_BYTE, rgba.Pix)
texture.Unbind(gl.TEXTURE_2D)
return texture
}
