// Internal function to generate a framebuffer/renderbuffer of the correct
// dimensions exactly once per execution
func getFBORBO(width, height int) *fborbo {
p := image.Point{width, height}
result, ok := framebuffers[p]
if ok {
return result
}
result = &fborbo{}
result.rbo = gl.GenRenderbuffer()
result.fbo = gl.GenFramebuffer()
result.fbo.Bind()
result.rbo.Bind()
gl.RenderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_COMPONENT, p.X, p.Y)
result.rbo.Unbind()
result.rbo.FramebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT,
gl.RENDERBUFFER)
result.fbo.Unbind()
framebuffers[p] = result
return result
}
// Internal function to generate a framebuffer/renderbuffer of the correct
// dimensions exactly once per execution
func getFBORBO(t *Texture) *fborbo {
p := image.Point{t.W, t.H}
result, ok := framebuffers[p]
if ok {
return result
}
result = &fborbo{}
result.rbo = gl.GenRenderbuffer()
OpenGLSentinel()
result.fbo = gl.GenFramebuffer()
OpenGLSentinel()
result.fbo.Bind()
result.rbo.Bind()
gl.RenderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_COMPONENT, t.W, t.H)
result.rbo.Unbind()
result.rbo.FramebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT,
gl.RENDERBUFFER)
result.fbo.Unbind()
framebuffers[image.Point{t.W, t.H}] = result
return result
}
// Creates a new Framebuffer.
func NewFramebuffer(w int, h int) (fb *Framebuffer, err error) {
var (
buffer gl.Framebuffer
texture gl.Texture
)
buffer = gl.GenFramebuffer()
buffer.Bind()
texture = gl.GenTexture()
texture.Bind(gl.TEXTURE_2D)
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, w, h, 0, gl.RGBA, gl.UNSIGNED_BYTE, nil)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
gl.FramebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0)
gl.DrawBuffer(gl.COLOR_ATTACHMENT0)
if gl.CheckFramebufferStatus(gl.FRAMEBUFFER) != gl.FRAMEBUFFER_COMPLETE {
err = fmt.Errorf("Framebuffer could not be set up")
return
}
fb = &Framebuffer{
Buffer: buffer,
Texture: texture,
Width: w,
Height: h,
}
return
}