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 (f *Font) setupTextRendering(color [3]byte, txt string) (gl.GLuint, *sdl.Surface, *sdl.Surface, *sdl.Surface, int, int) {
//
var texture gl.GLuint
/* Use SDL_TTF to render our text */
var col sdl.Color
col.R = color[0]
col.G = color[1]
col.B = color[2]
// get surface with text
initial := ttf.RenderText_Blended(f.font, txt, col)
/* Convert the rendered text to a known format */
w := next_p2(int(initial.W))
h := next_p2(int(initial.H))
intermediarya := sdl.CreateRGBSurface(0, w, h, 32,
0x00ff0000, 0x0000ff00, 0x000000ff, 0xff000000)
var rr *sdl.Rect = nil
intermediarya.Blit(rr, initial, rr)
intermediary := intermediarya.DisplayFormatAlpha()
/* Tell GL about our new texture */
gl.GenTextures(1, &texture)
gl.BindTexture(gl.TEXTURE_2D, texture)
gl.TexImage2D(gl.TEXTURE_2D, 0, 4, gl.GLsizei(w), gl.GLsizei(h), 0, gl.BGRA,
gl.UNSIGNED_BYTE, unsafe.Pointer(intermediary.Pixels))
gl.TexEnvi(gl.TEXTURE_ENV, gl.TEXTURE_ENV_MODE, gl.MODULATE)
/* GL_NEAREST looks horrible, if scaled... */
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
/* prepare to render our texture */
gl.Enable(gl.TEXTURE_2D)
gl.BindTexture(gl.TEXTURE_2D, texture)
gl.Color4f(1.0, 1.0, 1.0, 1.0)
gl.Enable(gl.BLEND)
// gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
gl.BlendFunc(gl.ONE, gl.ONE_MINUS_SRC_COLOR) // TODO : MAke real alpha work!
return texture, initial, intermediarya, intermediary, w, h
}
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 uploadTexture_RGBA32(w, h int, data []byte) gl.GLuint {
var id gl.GLuint
gl.GenTextures(1, &id)
gl.BindTexture(gl.TEXTURE_2D, id)
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, gl.GLsizei(w), gl.GLsizei(h), 0, gl.RGBA,
gl.UNSIGNED_BYTE, unsafe.Pointer(&data[0]))
if gl.GetError() != gl.NO_ERROR {
gl.DeleteTextures(1, &id)
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
}
// load in bitmap as a GL texture
func LoadGLTextures(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")
}
// Create the textures
gl.GenTextures(textures[:])
// First texture
gl.BindTexture(gl.TEXTURE_2D, uint(textures[0]))
gl.TexImage2D(
gl.TEXTURE_2D,
0,
3,
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.NEAREST)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)
// Second texture
gl.BindTexture(gl.TEXTURE_2D, uint(textures[1]))
gl.TexImage2D(gl.TEXTURE_2D, 0,
3,
int(image.W),
int(image.H),
0, textureFormat, gl.UNSIGNED_BYTE,
image.Pixels,
)
// Mipmapped filtering
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
// Third texture
gl.BindTexture(gl.TEXTURE_2D, uint(textures[2]))
gl.TexImage2D(gl.TEXTURE_2D, 0,
3,
int(image.W),
int(image.H),
0, textureFormat, gl.UNSIGNED_BYTE,
image.Pixels,
)
// Mipmapped filtering
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR_MIPMAP_NEAREST)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
glu.Build2DMipmaps(
gl.TEXTURE_2D,
3,
int(image.W),
int(image.H),
textureFormat,
image.Pixels,
)
}
func genTexture(into gl.Texture, from *sdl.Surface, format gl.GLenum) {
gl.BindTexture(gl.TEXTURE_2D, uint(into))
gl.TexImage2D(gl.TEXTURE_2D, 0, 3, int(from.W), int(from.H),
0, format, gl.UNSIGNED_BYTE, from.Pixels,
)
}