func Init() {
//gl.Enable(gl.DEPTH_TEST)
var tmpmaxa []float32 = []float32{0}
gl.GetFloatv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, tmpmaxa)
MaxAnisotropy = tmpmaxa[0]
log.Print("MaxAnisotropy: ", MaxAnisotropy)
// Anti-aliasing
gl.Enable(gl.LINE_SMOOTH)
gl.Enable(gl.BLEND)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
//gl.BlendFunc(gl.SRC_ALPHA, gl.DST_ALPHA)
//gl.BlendFunc(gl.SRC_ALPHA_SATURATE, gl.ONE)
gl.Hint(gl.LINE_SMOOTH_HINT, gl.NICEST)
gl.Hint(gl.GENERATE_MIPMAP_HINT, gl.NICEST)
extensions := gl.GetString(gl.EXTENSIONS)
if !strings.Contains(extensions, "GL_ARB_framebuffer_object") {
log.Panic("No FBO support :-(")
}
}
// Printf draws the given string at the specified coordinates.
// It expects the string to be a single line. Line breaks are not
// handled as line breaks and are rendered as glyphs.
//
// In order to render multi-line text, it is up to the caller to split
// the text up into individual lines of adequate length and then call
// this method for each line seperately.
func (f *Font) Printf(x, y float32, fs string, argv ...interface{}) error {
indices := []rune(fmt.Sprintf(fs, argv...))
if len(indices) == 0 {
return nil
}
// Runes form display list indices.
// For this purpose, they need to be offset by -FontConfig.Low
low := f.Config.Low
for i := range indices {
indices[i] -= low
}
var vp [4]int32
gl.GetIntegerv(gl.VIEWPORT, vp[:])
gl.PushAttrib(gl.TRANSFORM_BIT)
gl.MatrixMode(gl.PROJECTION)
gl.PushMatrix()
gl.LoadIdentity()
gl.Ortho(float64(vp[0]), float64(vp[2]), float64(vp[1]), float64(vp[3]), 0, 1)
gl.PopAttrib()
gl.PushAttrib(gl.LIST_BIT | gl.CURRENT_BIT | gl.ENABLE_BIT | gl.TRANSFORM_BIT)
{
gl.MatrixMode(gl.MODELVIEW)
gl.Disable(gl.LIGHTING)
gl.Disable(gl.DEPTH_TEST)
gl.Enable(gl.BLEND)
gl.Enable(gl.TEXTURE_2D)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
gl.TexEnvf(gl.TEXTURE_ENV, gl.TEXTURE_ENV_MODE, gl.MODULATE)
f.Texture.Bind(gl.TEXTURE_2D)
var mv [16]float32
gl.GetFloatv(gl.MODELVIEW_MATRIX, mv[:])
gl.PushMatrix()
{
gl.LoadIdentity()
mgw := float32(f.maxGlyphWidth)
mgh := float32(f.maxGlyphHeight)
switch f.Config.Dir {
case LeftToRight, TopToBottom:
gl.Translatef(x, float32(vp[3])-y-mgh, 0)
case RightToLeft:
gl.Translatef(x-mgw, float32(vp[3])-y-mgh, 0)
}
gl.MultMatrixf(&mv)
gl.CallLists(len(indices), gl.UNSIGNED_INT, indices)
}
gl.PopMatrix()
f.Texture.Unbind(gl.TEXTURE_2D)
}
gl.PopAttrib()
gl.PushAttrib(gl.TRANSFORM_BIT)
gl.MatrixMode(gl.PROJECTION)
gl.PopMatrix()
gl.PopAttrib()
return glh.CheckGLError()
}