// newFBO will generate a new Frame Buffer Object for use with the canvas
func newFBO(texture gl.Texture) (gl.Framebuffer, uint32) {
// get currently bound fbo to reset to it later
current_fbo := gl.GetBoundFramebuffer()
framebuffer := gl.CreateFramebuffer()
gl.BindFramebuffer(gl.FRAMEBUFFER, framebuffer)
if texture.Valid() {
gl.FramebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0)
// Initialize the texture to transparent black.
gl.ClearColor(0.0, 0.0, 0.0, 0.0)
gl.Clear(gl.COLOR_BUFFER_BIT)
}
status := gl.CheckFramebufferStatus(gl.FRAMEBUFFER)
// unbind framebuffer
gl.BindFramebuffer(gl.FRAMEBUFFER, current_fbo)
return framebuffer, uint32(status)
}
// Clear will clear everything already rendered to the screen and set is all to
// the *Color provided.
func ClearC(c *Color) {
gl.ClearColor(c[0], c[1], c[2], c[3])
gl.Clear(gl.COLOR_BUFFER_BIT | gl.STENCIL_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
}