Example #1
0
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
}
// load in bitmap as a GL texture
func LoadGLTextures(path string) {
	// storage space for the textures
	image, format := LoadImage(path)

	// Create the textures
	gl.GenTextures(textures[:])

	genTexture(textures[0], image, format)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)

	genTexture(textures[1], image, format)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)

	genTexture(textures[2], image, format)
	gl.TexParameteri(gl.TEXTURE_2D, gl.GENERATE_MIPMAP, gl.TRUE)
}
Example #3
0
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
}
Example #4
0
// 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,
  )
}